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Handover in detail_23009-3e0 (1)
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Handover in detail_23009-3e0 (1)

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Handover in detail_23009-3e0 (1)

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  • 1. 3GPP TS 23.009 V3.14.0 (2003-06) Technical Specification 3rd Generation Partnership Project; Technical Specification Group Core Network; Handover procedures (Release 1999) R GLOBAL SYSTEM FOR MOBILE COMMUNICATIONS The present document has been developed within the 3rd Generation Partnership Project (3GPP TM) and may be further elaborated for the purposes of 3GPP. The present document has not been subject to any approval process by the 3GPP Organisational Partners and shall not be implemented. This Specification is provided for future development work within 3GPP only. The Organisational Partners accept no liability for any use of this Specification. Specifications and reports for implementation of the 3GPP TM system should be obtained via the 3GPP Organisational Partners' Publications Offices.
  • 2. Release 1999 2 3GPP TS 23.009 V3.14.0 (2003-06) Keywords GSM, UMTS, handover, network 3GPP Postal address 3GPP support office address 650 Route des Lucioles - Sophia Antipolis Valbonne - FRANCE Tel.: +33 4 92 94 42 00 Fax: +33 4 93 65 47 16 Internet http://www.3gpp.org Copyright Notification No part may be reproduced except as authorized by written permission. The copyright and the foregoing restriction extend to reproduction in all media. © 2003 3GPP Organizational Partners (ARIB, CWTS, ETSI, T1, TTA, TTC). All rights reserved. 3GPP
  • 3. Release 1999 3 3GPP TS 23.009 V3.14.0 (2003-06) Contents Foreword.............................................................................................................................................................6 1 Scope ........................................................................................................................................................7 2 References ................................................................................................................................................8 3 Abbreviations ...........................................................................................................................................9 4 Role, functional composition of MSCs and interfaces for handover .......................................................9 4.1 4.1.1 4.1.2 4.2 4.2.1 4.2.2 4.3 4.3.1 4.3.2 4.4 4.4.1 4.4.2 MSC-A .................................................................................................................................................................... 9 Role of MSC-A.................................................................................................................................................. 9 Functional composition of MSC-A and its interfaces for handover ................................................................ 10 MSC-B .................................................................................................................................................................. 12 Role of MSC-B ................................................................................................................................................ 12 Functional composition of MSC-B and its interfaces for handover................................................................. 13 3G_MSC-A ........................................................................................................................................................... 14 Role of 3G_MSC-A ......................................................................................................................................... 14 Functional composition of 3G_MSC-A and its interfaces for handover/relocation......................................... 16 3G_MSC-B............................................................................................................................................................ 18 Role of 3G_MSC-B ......................................................................................................................................... 18 Functional composition of 3G_MSC-B and its interfaces for handover/relocation......................................... 20 5 Handover initiation conditions ...............................................................................................................21 6 General description of the procedures for intra - MSC handovers.........................................................22 6.1 Procedure for Intra-MSC Handovers..................................................................................................................... 22 6.2 Procedure for Intra-3G_MSC Handovers .............................................................................................................. 24 6.2.1 Intra-3G_MSC Handover from UMTS to GSM .............................................................................................. 24 6.2.1.1 With no bearer or one bearer ........................................................................................................................... 24 6.2.1.2 With multiple bearers (Optional functionality)................................................................................................ 25 6.2.2 Intra-3G_MSC GSM to UMTS Handover....................................................................................................... 25 6.2.3 Procedure for Intra-3G_MSC SRNS Relocation ............................................................................................. 27 6.2.3.1 With no bearer or one bearer ........................................................................................................................... 28 6.2.3.2 With multiple bearers (Optional functionality)................................................................................................ 29 7 General description of the procedures for inter - MSC handovers.........................................................29 7.1 7.2 7.3 7.3.1 7.3.2 7.4 7.4.1 7.4.2 Basic handover procedure requiring a circuit connection between MSC-A and MSC-B...................................... 30 Basic handover procedure not requiring the establishment of a circuit connection between MSC-A and MSC-B............................................................................................................................................................. 32 Procedure for subsequent handover requiring a circuit connection....................................................................... 33 Description of subsequent handover procedure i): MSC-B to MSC-A............................................................ 33 Description of the subsequent handover procedure ii): MSC-B to MSC-B' .................................................... 34 Procedure for subsequent handover not requiring a circuit connection................................................................. 35 Description of the subsequent handover procedure without circuit connection i): MSC-B to MSC-A ........... 36 Description of the subsequent handover procedure without circuit connection ii): MSC-B to MSC-B' ......... 36 8 General Description of the procedures for inter - 3G_MSC handovers.................................................37 8.1 Handover UMTS to GSM ..................................................................................................................................... 37 8.1.1 Basic Handover procedure requiring a circuit connection between 3G_MSC -A and MSC-B ....................... 38 8.1.1.1 With one circuit connection ............................................................................................................................. 39 8.1.1.2 With multiple circuit connections (Optional functionality) ............................................................................. 40 8.1.2 Basic UMTS to GSM Handover procedure not requiring the establishment of a circuit connection between 3G_MSC-A and MSC-B .............................................................................................................. 40 8.1.3 Procedure for subsequent UMTS to GSM handover requiring a circuit connection........................................ 41 8.1.3.1 Description of subsequent UMTS to GSM handover procedure i): 3G_MSC-B to MSC-A ........................... 42 8.1.3.1.1 With one circuit connection ....................................................................................................................... 42 8.1.3.1.2 With multiple circuit connections (Optional functionality)........................................................................ 42 8.1.3.2 Description of subsequent UMTS to GSM handover procedure ii): 3G_MSC-B to MSC-B' ......................... 43 8.1.3.2.1 With one circuit connection ....................................................................................................................... 43 8.1.3.2.2 With multiple circuit connections (Optional functionality)........................................................................ 43 3GPP
  • 4. Release 1999 4 3GPP TS 23.009 V3.14.0 (2003-06) 8.1.4 8.1.4.1 8.1.4.2 Procedure for subsequent UMTS to GSM handover not requiring a circuit connection ................................. 45 Description of subsequent UMTS to GSM handover procedure i): 3G_MSC-B to MSC-A ........................... 45 Description of the subsequent UMTS to GSM handover procedure without circuit connection ii): 3G_MSC-B to MSC-B'......................................................................................................................... 45 8.2 Handover GSM to UMTS ..................................................................................................................................... 46 8.2.1 Basic Handover procedure requiring a circuit connection between MSC-A and 3G_MSC-B ........................ 47 8.2.2 Basic GSM to UMTS Handover procedure not requiring the establishment of a circuit connection between MSC-A and 3G_MSC-B .............................................................................................................. 49 8.2.3 Procedure for subsequent GSM to UMTS handover requiring a circuit connection........................................ 50 8.2.3.1 Description of subsequent GSM to UMTS handover procedure i): MSC-B to 3G_MSC-A ........................... 51 8.2.3.2 Description of subsequent GSM to UMTS handover procedure ii): MSC-B to 3G_MSC-B' ......................... 51 8.2.4 Procedure for subsequent GSM to UMTS handover not requiring a circuit connection ................................. 53 8.2.4.1 Description of subsequent GSM to UMTS handover procedure without circuit connection i): MSC-B to 3G_MSC-A........................................................................................................................................... 54 8.2.4.2 Description of subsequent GSM to UMTS handover procedure without circuit connection ii): MSC-B to 3G_MSC-B' .......................................................................................................................................... 54 8.3 SRNS Relocation................................................................................................................................................... 55 8.3.1 Basic relocation procedure requiring a circuit connection between 3G_MSC-A and 3G_MSC-B ................. 56 8.3.1.1 With one circuit connection ............................................................................................................................. 57 8.3.1.2 With multiple circuit connections (Optional functionality) ............................................................................. 59 8.3.1.2.1 3G_MSC-B does not support multiple bearers........................................................................................... 59 8.3.1.2.2 3G_MSC-B supports multiple bearers ....................................................................................................... 59 8.3.2 Basic relocation procedure not requiring the establishment of a circuit connection between 3G_MSC-A and 3G_MSC-B.......................................................................................................................................... 60 8.3.3 Procedure for subsequent relocation requiring a circuit connection ................................................................ 61 8.3.3.1 Description of subsequent relocation procedure i): 3G_MSC-B to 3G_MSC-A............................................. 61 8.3.3.1.1 With one circuit connection ....................................................................................................................... 61 8.3.3.1.2 With multiple circuit connections (Optional functionality)........................................................................ 62 8.3.3.2 Description of subsequent relocation procedure ii): 3G_MSC-B to 3G_MSC-B' ........................................... 62 8.3.3.2.1 With one circuit connection ....................................................................................................................... 62 8.3.3.2.2 With multiple circuit connections (Optional functionality)........................................................................ 63 8.3.4 Procedure for subsequent relocation not requiring a circuit connection .......................................................... 64 8.3.4.1 Description of subsequent relocation procedure i): 3G_MSC-B to 3G_MSC-A............................................. 65 8.3.4.2 Description of subsequent relocation procedure ii): 3G_MSC-B to 3G_MSC-B'' .......................................... 65 9 Detailed procedures in MSC-A ..............................................................................................................66 9.1 9.2 9.3 9.4 9.5 9.6 BSS/MSC and MS/MSC procedures in MSC-A (functional unit 1) ..................................................................... 66 Call control procedures MSC-A (functional unit 2) .............................................................................................. 67 Handover control procedures MSC-A (functional unit 3) ..................................................................................... 68 MAP procedures in MSC-A (functional unit 4) .................................................................................................... 69 Interworking between Handover control procedures and MAP procedures in MSC-A ........................................ 69 Compatibility with GSM Phase 1.......................................................................................................................... 69 10 Detailed procedures in MSC-B ..............................................................................................................70 10.1 10.2 10.3 10.4 10.5 10.6 11 11.1 11.2 11.3 11.4 11.5 11.6 11.7 12 12.1 12.2 BSS/MSC (MS/BSS) procedures MSC-B (functional unit 1) ......................................................................... 70 Call control procedures MSC-B (functional unit 2)......................................................................................... 70 Handover control procedures MSC-B (functional unit 3)................................................................................ 71 MAP procedures MSC-B (functional unit 4) ................................................................................................... 71 Interworking between Handover control procedures and MAP procedures in MSC-B................................... 72 Compatibility with GSM Phase 1 .................................................................................................................... 72 Detailed procedures in 3G_MSC-A .......................................................................................................72 RNC/BSC/3G_MSC and UE/MS/3G_MSC procedures in 3G_MSC-A (functional unit 1) ........................... 72 Call control procedures 3G_MSC-A (functional unit 2).................................................................................. 72 Handover/Relocation control procedures 3G_MSC-A (functional unit 3) ...................................................... 74 MAP procedures in 3G_MSC-A (functional unit 4)........................................................................................ 76 Interworking between Handover/Relocation control procedures and MAP procedures in 3G_MSC-A ......... 76 Compatibility with GSM Phase 1 .................................................................................................................... 77 Protocol interworking ...................................................................................................................................... 77 Detailed procedures in 3G_MSC-B .......................................................................................................77 RNC/BSC/3G_MSC (UE/MS/RNC/BSC) procedures in 3G_MSC-B (functional unit 1) .............................. 77 Call control procedures 3G_MSC-B (functional unit 2).................................................................................. 77 3GPP
  • 5. Release 1999 12.3 12.4 12.5 12.6 12.7 13 13.1 13.2 13.3 13.4 13.4.1 13.4.2 14 14.1 14.2 14.3 15 5 3GPP TS 23.009 V3.14.0 (2003-06) Handover/Relocation control procedures in 3G_MSC-B (functional unit 3) .................................................. 78 MAP procedures in 3G_MSC-B (functional unit 4) ........................................................................................ 80 Interworking between Handover/Relocation control procedures and MAP procedures in 3G_MSC-B.......... 80 Compatibility with GSM Phase 1 .................................................................................................................... 80 Protocol interworking ...................................................................................................................................... 80 Subsequent channel assignment using a circuit connection between MSC-A and MSC-B ...................81 GSM handover................................................................................................................................................. 81 UMTS to GSM handover................................................................................................................................. 82 GSM to UMTS handover................................................................................................................................. 83 SRNS Relocation ............................................................................................................................................. 84 Without circuit connection............................................................................................................................... 84 With circuit connection (Optional functionality) ............................................................................................. 84 Directed retry handover..........................................................................................................................85 GSM handover................................................................................................................................................. 85 GSM to UMTS handover................................................................................................................................. 86 UMTS to GSM handover................................................................................................................................. 87 SDL diagrams.........................................................................................................................................88 Annex A (informative): Change history .............................................................................................266 3GPP
  • 6. Release 1999 6 3GPP TS 23.009 V3.14.0 (2003-06) Foreword This Technical Specification (TS) has been produced by the 3rd Generation Partnership Project (3GPP). The present document provides a mechanism giving reliable transfer of signalling messages within the 3GPP system. The contents of the present document are subject to continuing work within the TSG and may change following formal TSG approval. Should the TSG modify the contents of the present document, it will be re-released by the TSG with an identifying change of release date and an increase in version number as follows: Version x.y.z where: x the first digit: 1 presented to TSG for information; 2 presented to TSG for approval; 3 or greater indicates TSG approved document under change control. y the second digit is incremented for all changes of substance, i.e. technical enhancements, corrections, updates, etc. z the third digit is incremented when editorial only changes have been incorporated in the document. 3GPP
  • 7. Release 1999 1 7 3GPP TS 23.009 V3.14.0 (2003-06) Scope The present document contains a detailed description of the handover procedures to be used in PLMNs. The purpose of the handover procedures, as described in the present document, are to ensure that the connection to the Mobile Station (MS) or User Equipment (UE) is maintained as it moves from one cell or radio network to another. The document defines the circuit switched handover functionality based on the service requirements in 3GPP TS 22.129 [9]. The present document considers the following four cases: i) handover between Base Stations connected to the same MSC, this is termed an Intra-MSC handover; ii) handover between Radio Network Subsystems connected to the same 3G_MSC, this is termed an Intra-3G_MSC handover/relocation. This case also includes inter-system handover between RNS and BSS if the 3G_MSC supports the A-interface; iii) handover between Base Stations connected to different MSCs, this is termed an Inter-MSC handover. This category can be sub-divided into three further procedures: a) the Basic Inter-MSC Handover procedure, where the MS is handed over from a controlling MSC (MSC-A) to another MSC (MSC-B); b) the Subsequent Inter-MSC Handover procedure, where the MS is handed over from MSC-B to a third MSC (MSC-B'); c) the Subsequent Inter-MSC handback, where the MS is handed back from MSC-B to MSC-A. iv) handover between Radio Network Subsystems connected to different 3G_MSCs, this is termed an Inter3G_MSC handover/relocation. This category can be divided into three further sub-procedures: a) the Inter-3G_MSC Handover procedure from UMTS to GSM, where the UE/MS is handed over from a controlling 3G_MSC (3G_MSC-A) to an MSC (MSC-B); b) the Inter-3G_MSC Handover procedure from GSM to UMTS, where the UE/MS is handed over from a controlling MSC (MSC-A) to a 3G_MSC (3G_MSC-B); c) the Inter-3G_MSC Relocation procedure, where the UE is relocated from 3G_MSC-A to 3G_MSC-B. This procedure can also be combined with a hard change of radio resources (Hard Handover with switch in the core network). The MSC in this category can optionally be a 3G_MSC supporting the A-interface. The three sub-procedures do also cover subsequent handover/relocation to a third MSC-B' or 3G_MSC-B' and subsequent handover/relocation back to MSC-A or 3G_MSC-A. In both cases i) and iii) the same procedures as defined in the 3GPP TS 08.08 [5] and the 3GPP TS 24.008 [10] shall be used on the A-interface and on the Radio Interface, respectively. In case ii) the same procedures as defined in the 3GPP TS 25.413 [11] and the 3GPP TS 24.008 [10] shall be used on the Iu-interface. If the 3G_MSC in case ii) also supports the A-interface, the 3GPP TS 08.08 [5] and the 3GPP TS 24.008 [10] shall be used on the A-interface. In case iii) the handover procedures shall transport the A-interface messages between MSC-A and MSC-B described in the Mobile Application Part (MAP), 3GPP TS 29.002 [12]. In case iv) the handover procedures shall transport the A-interface messages between 3G_MSC and MSC described in the Mobile Application Part (MAP), 3GPP TS 29.002 [12]. In case iv) the relocation procedure shall transport the Iu-interface messages between 3G_MSC-A and 3G_MSC-B described in the Mobile Application Part (MAP), 3GPP TS 29.002 [12]. The interworking between the 3GPP TS 29.002 [12] protocol and the 3GPP TS 08.08 [5] protocol is described in the 3GPP TS 29.010 [8]. Handovers, which take place on the same MSC are termed Intra-MSC handovers; this includes both Inter-BSS and Intra-BSS handovers. 3GPP
  • 8. Release 1999 8 3GPP TS 23.009 V3.14.0 (2003-06) Handovers, which take place on the same 3G_MSC are termed Intra-3G_MSC handovers; this includes Inter-RNS handovers and optionally RNS to BSS and BSS to RNS handovers. The present document also covers the requirements for handover in ongoing GSM voice group calls, directed retry and handover without a circuit connection between (U)MSCs. The present document does not consider the case of handovers between radio channels on the same BSS (Intra-BSS handover) or the handover of packet radio services. The Inter-RNS handover case that results in a relocation is covered by the present document but not other Inter-RNS or Intra-RNS handover cases. For voice broadcast calls in GSM, the speaker uses normal point-to-point handover procedures, whilst the listeners use idle mode cell reselection procedures, as for the voice group call listeners. Voice group calls is only applicable to GSM and handover of voice group calls is therefore only possible in GSM. Inter-MSC hand-over imposes a few limitations on the system. After inter-MSC hand-over: - call re-establishment is not supported. The list of 3GPP TS 08.08 [5] features supported during and after Inter-MSC handover is given in 3GPP TS 09.08 [7]. In the Inter-MSC handover case, the interworking between a Phase 1 BSSMAP protocol possibly used by one MSC and the Phase 2 BSSMAP protocol used in the Phase 2 MAP protocol on the E-interface is performed by this MSC. NOTE: 2 The message primitive names used in the SDL diagrams and message flows in the present document do not represent the actual messages specified in the GSM or 3GPP stage 3 technical specifications. The primitive names are only intended to be indicative of their use in the present document. References The following documents contain provisions which, through reference in this text, constitute provisions of the present document. • References are either specific (identified by date of publication, edition number, version number, etc.) or non-specific. • For a specific reference, subsequent revisions do not apply. • For a non-specific reference, the latest version applies. In the case of a reference to a 3GPP document (including a GSM document), a non-specific reference implicitly refers to the latest version of that document in the same Release as the present document. [1] ITU-T Recommendation Q.118: "Special release arrangements". [2] Void. [2a] 3GPP TR 21.905: "3G Vocabulary". [3] 3GPP TS 03.68: "Voice Group Call Service (VGCS) - Stage 2". [4] 3GPP TS 05.08: "Radio subsystem link control". [5] 3GPP TS 08.08: "Mobile Switching Centre - Base Station System (MSC - BSS) interface; Layer 3 specification". [6] 3GPP TS 08.58: "Base Station Controller - Base Transceiver Station (BSC - BTS) interface; Layer 3 specification". [7] 3GPP TS 09.08: "Application of the Base Station System Application Part (BSSAP) on the E-interface". [8] 3GPP TS 29.010: "Information element mapping between Mobile Station - Base Station System (MS-BSS) and Base Station System - Mobile-services Switching Centre (BSS - MSC); Signalling procedures and the Mobile Application Part (MAP)". 3GPP
  • 9. Release 1999 9 3GPP TS 23.009 V3.14.0 (2003-06) [9] 3GPP TS 22.129: "Handover Requirements between UMTS and GSM or other Radio Systems". [10] 3GPP TS 24.008: "Mobile radio interface layer 3 specification". [11] 3GPP TS 25.413: "UTRAN Iu interface RANAP signalling". [12] 3GPP TS 29.002: "Mobile Application Part (MAP) specification". [13] 3GPP TS 25.303: "Interlayer procedures in Connected Mode". [14] 3GPP TS 25.331: "RRC Protocol Specification". [15] 3GPP TS 29.108: "Application of the Radio Access Network Application Part (RANAP) on the Einterface". [16] ITU-T Recommendation G.711: "Pulse code modulation (PCM) of voice frequencies". [17] 3GPP TS 23.135: "Multicall supplementary service - Stage 2". 3 Abbreviations For the purpose of the present document, the following abbreviations apply: 3G_MSC 3G_MSC-A 3G_MSC-B 3G_MSC-B' BSC BSS BSS-A BSS-B BTS ISC MS MSC MSC-A MSC-B MSC-B' RNC RNS UE UE/MS USIM A third generation MSC that supports the Iu interface and optionally the A interface The controlling 3G_MSC on which the call was originally established The 3G_MSC to which the UE is handed over in a Basic Handover The 3G_MSC to which the UE is handed over in a Subsequent Handover Base Station Controller Base Station System The BSS from which the MS is being handed over The BSS to which the MS is being handed over Base Transceiver Station International Switching Centre Mobile Station A second generation Mobile Services Switching Centre that only supports the A interface The controlling MSC on which the call was originally established The MSC to which the MS is handed over in a Basic Handover The MSC to which the MS is handed over in a Subsequent Handover Radio Network Controller Radio Network Subsystem A User Equipment is a terminal that supports USIM and the UMTS Uu interface A terminal that supports USIM, SIM, the Uu interface and the Um interface UMTS Subscriber Identity Module Other abbreviations used in the GSM specifications are listed in 3GPP TR 21.905[2a]. 4 Role, functional composition of MSCs and interfaces for handover 4.1 MSC-A 4.1.1 Role of MSC-A In the Intra-MSC handover case, the MSC-A (simply termed MSC) controls the call, the mobility management and the radio resources before, during and after an Intra-MSC handover. When BSSAP procedures have to be performed, they are initiated and driven by MSC-A. 3GPP
  • 10. Release 1999 10 3GPP TS 23.009 V3.14.0 (2003-06) In the Inter-MSC handover case, MSC-A is the MSC which controls the call and the mobility management of the Mobile during the call, before, during and after a basic or subsequent handover. When BSSAP procedures related to dedicated resources have to be performed towards the MS, they are initiated and driven by MSC-A. The MSC-A MSC-B interface works as a MSC - BSS interface for a subset of BSSMAP procedures. These BSSMAP procedures, described in 3GPP TS 09.08 [7] are only those related to dedicated resources. The DTAP signalling is relayed transparently by MSC-B between MSC-A and the MS. During a basic handover, MSC-A initiates and controls all the handover procedure, from its initiation (reception of Handover Required from BSS-A on A-interface) until its completion (reception of Handover Complete from MSC-B on E-interface). During a subsequent handover back to MSC-A, MSC-A acts as a BSS towards MSC-B, which controls the handover procedure until the termination in MSC-A of the handover radio resources allocation (sending of the Handover Request Acknowledge to MSC-B from MSC-A). Then all handover related messages shall terminate at MSC-A (e.g. Handover Detect/Complete from BSS-B, Handover Failure from BSS-A). During a subsequent handover to a third MSC, MSC-A works towards MSC-B' as described above in the basic handover paragraph and towards MSC-B as described above in subsequent handover paragraph. In the Inter-System, inter-MSC handover case, MSC-A is the MSC which controls the call and the mobility management of the Mobile during the call, before, during and after a basic or subsequent handover. When BSSAP procedures related to dedicated resources have to be performed towards the MS, they are initiated and driven by MSC-A. The MSC-A - 3G_MSC-B interface works as a MSC - BSS interface for a subset of BSSMAP procedures. These BSSMAP procedures, described in 3GPP TS 09.08 [7] are only those related to dedicated resources. The DTAP signalling is relayed transparently by 3G_MSC-B between MSC-A and the MS. During a basic inter-system handover, MSC-A initiates and controls all the handover procedure, from its initiation (reception of Handover Required from BSS-A on A-interface) until its completion (reception of Handover Complete from 3G_MSC-B on E-interface). During a subsequent inter-system handover back to MSC-A, MSC-A acts as a BSS towards 3G_MSC-B, which controls the handover procedure until the termination in MSC-A of the handover radio resources allocation (sending of the Handover Request Acknowledge to 3G_MSC-B from MSC-A). Then all handover related messages shall terminate at MSC-A (e.g. Handover Detect/Complete from BSS-B, Handover Failure from BSS-A). During a subsequent inter-system handover to a third MSC, MSC-A works towards 3G_MSC-B' as described above in the basic inter-system handover paragraph and towards 3G_MSC-B as described above in subsequent inter-system handover paragraph. 4.1.2 Functional composition of MSC-A and its interfaces for handover In order to simplify the description of the handover procedures the controlling MSC (MSC-A) can be considered to be composed of five functional units, as shown in figure 1. Signalling functions 1) BSC/MSC (MS/BSC) Procedures MSC-A. This unit is used to control the signalling between the MSC, BSC and MS. Interface A' is the connection to the old BSC and interface A'' is the connection to the new BSC, when an Intra-MSC handover takes place. Interface x represents the interworking connection to the Handover Control Procedures MSC-A. 2) Call Control Procedures MSC-A. This unit is used to control the call. Interface B' is used for normal call control procedures. When a Basic handover from MSC-A to MSC-B is to be performed then interface B'' is employed to provide a signalling and call control connection to MSC-B. If a Subsequent handover to MSC-B' is to be performed then interface B''' is used. Similarly, when a Basic inter-system handover from MSC-A to 3G_MSC-B is to be performed, then interface B'' is employed to provide a signalling and call control connection to 3G_MSC-B. If a subsequent inter-system handover to 3G_MSC-B' is to be performed, then interface B''' is used. 3) Handover Control Procedures MSC-A. This unit provides both the overall control of the handover procedure and interworking between the internal interfaces (x, y and z). 4) MAP Procedures MSC-A. This unit is responsible for controlling the exchange of MAP messages between MSCs during an Inter-MSC handover, or between MSC-A and 3G_MSC-B during an Inter-system Inter-MSC handover. This unit communicates with the Handover Control Procedures MSC-A via interface z. 3GPP
  • 11. Release 1999 11 3GPP TS 23.009 V3.14.0 (2003-06) Switching functions 5) Switch and Handover Device MSC-A. For all calls, except for ongoing voice group calls (see 3GPP TS 03.68 [3] for a definition) this unit is responsible for connecting the new path into the network via interface B'. In the case of ongoing voice group calls this unit is responsible for maintaining the connection between the down link group call channels and the active uplink. In specific cases it may be unnecessary to take any explicit action in the MSC concerning the handover device. The handover device interconnections are illustrated in figure 2. Signalling functions Call 2 Control Procedures MSC-A y A’ 1 BSC/MSC (MS/BSC) Procedures MSC-A A’’ 3 x B’ B’’ B’’’ Handover Control Procedures MSC-A z 4 MAP Procedures MSC-A C Switching control A’ Switching functions 5 A’’ B’ Switch and Handover Device MSC-A B’’ B’’’ Figure 1: Functional composition of the controlling MSC (MSC-A) for supporting handover For MS to MS calls in the same MSC the configuration in Figure 2b) applies. In this case interface B'' is internal to MSC-A and does not connect to another MSC. The handover device can either be a three-party bridge or a switching facility without three-party connection capabilities. For a three-party bridge configuration the states of the handover device are as shown in table 1. The threeparty configuration exists in the intermediate state. This type of handover device may reduce the interruption time. However, this may require noise reduction if one of the radio channels is unterminated at some time in the intermediate state. For a handover device consisting of a simple switch there will be no intermediate state. Table 1: States of the handover device Resulting Connection Successful Unsuccessful Procedure Procedure B' to A'' B' to A' Case Initial Connection Intermediate Connection Figure 2a) B' to A' B' to A' and A'' Figure 2b) B' to A' B' to A' and B'' B' to B'' B' to A' Figure 2c) B' to B'' B' to B''and B''' B' to B''' B' to B'' 3GPP
  • 12. Release 1999 12 A’ 3GPP TS 23.009 V3.14.0 (2003-06) B’ A’’ a) Intra-MSC Handover case. A’ B’ B’’ b) Basic Handover case and handover of MS to MS call in the same MSC. B’ B’’ B’’’ c) Subsequent Handover case NOTE: In a) and b) A’ is released after handover; In c) B’’ is released after handover. Figure 2: Connections in the handover device (Unit 5) 4.2 MSC-B 4.2.1 Role of MSC-B In the Intra-MSC handover case, the MSC-B keeps the control of the whole Intra-MSC handover procedure. MSC-B notifies MSC-A or 3G_MSC-A of successful intra -MSC-B handover completion HANDOVER-PERFORMED message. by using the A- In the Inter-MSC handover case, the role of MSC-B (MSC-B') is only to provide radio resources control within its area. This means that MSC-B keeps control of the radio resources connection and release towards BSS-B. MSC-B will do some processing on the BSSMAP information received on the E-interface or A-interface whereas it will relay the DTAP information transparently between A-interface and E-interface. MSC-A initiates and drives a subset of BSSMAP procedures towards MSC-B, while MSC-B controls them towards its BSSs to the extent that MSC-B is responsible for the connections of its BSSs. The release of the dedicated resources between MSC-B and BSS-B is under the responsibility of MSC-B and BSS-B, and is not directly controlled by MSC-A. When clearing is to be performed due to information received from BSS-B, MSC-B shall transfer this clearing indication to MSC-A, to clear its connection with BSS-B, to terminate the dialogue with MSC-A through the E-interface, and to release its circuit connection with MSC-A, if any. In the same way, the release of the connection to its BSS-B, is initiated by MSC-B, when the dialogue with MSC-A ends normally and a release is received from the circuit connection with MSC-A, if any, or when the dialogue with the MSC-A ends abnormally. When a release is received by MSC-B for the circuit connection with MSC-A then MSC-B shall release the circuit connection. 3GPP
  • 13. Release 1999 13 3GPP TS 23.009 V3.14.0 (2003-06) In the Inter-system Inter-MSC handover case, the role of MSC-B (MSC-B') is only to provide radio resources control within its area. This means that MSC-B keeps control of the radio resources connection and release towards BSS-B. MSC-B will do some processing on the BSSMAP information received on the E-interface or A-interface whereas it will relay the DTAP information transparently between A-interface and E-interface. 3G_MSC-A initiates and drives a subset of BSSMAP procedures towards MSC-B, while MSC-B controls them towards its BSSs to the extent that MSC-B is responsible for the connections of its BSSs. The release of the dedicated resources between MSC-B and BSS-B is under the responsibility of MSC-B and BSS-B, and is not directly controlled by 3G_MSC-A. When clearing is to be performed due to information received from BSS-B, MSC-B shall transfer this clearing indication to 3G_MSC-A, to clear its connection with BSS-B, to terminate the dialogue with 3G_MSC-A through the E-interface, and to release its circuit connection with 3G_MSC-A, if any. In the same way, the release of the connection to its BSS-B, is initiated by MSC-B, when the dialogue with 3G_MSC-A ends normally and a release is received from the circuit connection with MSC-A, if any, or when the dialogue with the MSC-A ends abnormally. When a release is received by MSC-B for the circuit connection with 3G_MSC-A then MSC-B shall release the circuit connection. 4.2.2 Functional composition of MSC-B and its interfaces for handover The functional composition of an MSC acting as MSC-B is essentially the same as that of MSC-A. However, there are some differences. The functional units are as follows (see figure 3). Signalling functions 1) BSC/MSC (MS/BSC) Procedures MSC-B. This unit is used to control the signalling between the MSC, BSC and MS. Interface A'' is the connection to the new BSC, when an Intra-MSC handover takes place. Interface x represents the interworking connection to the Handover Control Procedures MSC-B. 2) Call Control Procedures MSC-B. This unit is used for normal call control and signalling to MSC-A, or 3G_MSC-A in the case of inter-system inter-MSC handover. 3) Handover Control Procedures MSC-B. This unit provides both the overall control of the handover procedure and interworking between the internal interfaces (x, y and z) in MSC-B. 4) MAP Procedures MSC-B. This unit is responsible for controlling the exchange of MAP messages between MSC-A, or 3G_MSC-A, and MSC-B and for signalling to the VLR in MSC-B. Switching functions 5) Switch MSC-B. For all calls, except ongoing voice group calls (see 3GPP TS 03.68 [3] for a definition) this unit is responsible, with BSS-B, for connecting the circuit from MSC-A, or 3G_MSC-A, to BSS-B. This unit may also need to act as a handover device for Intra-MSC handovers controlled by MSC-B. In the case of ongoing voice group calls this unit is responsible for maintaining the connection between the group member currently assigned the uplink and the distribution device. In specific cases it may be unnecessary to take any explicit action in the MSC concerning the handover device. 3GPP
  • 14. Release 1999 14 Signalling functions 2 3GPP TS 23.009 V3.14.0 (2003-06) Call Control Procedures MSC-B B’’ y A’ A’’ 1 BSC/MSC (MS/BSC) Procedures MSC-B x 3 Handover Control Procedures MSC-B z 4 MAP Procedures MSC-B C Switching control A’ Switching functions 5 Switch MSC-B B’’ A’’ Figure 3: Functional composition of 4.3 MSC-B for supporting handover 3G_MSC-A For roles and functional composition of the 3G_MSC-A working as pure GSM MSC, please see previous clause ("MSC-A"). 4.3.1 Role of 3G_MSC-A In the Intra-3G_MSC handover/relocation case, the 3G_MSC-A (simply termed 3G_MSC) controls the call, the mobility management and the radio resources before, during and after an Intra-3G_MSC handover/relocation. When RANAP or BSSMAP procedures have to be performed, they are initiated and driven by 3G_MSC-A. In the case of intra-MSC handover of a speech call, 3G_MSC-A controls the transcoder in the core network. The 3G_MSC-A determines if a transcoder is required to be inserted or released in the CN. In the case of Inter-3G_MSC relocation, 3G_MSC-A links out the transcoder. In the Inter-3G_MSC relocation case, 3G_MSC-A is the 3G_MSC that controls the call and the mobility management of the UE during the call, before, during and after a basic or subsequent relocation. When RANAP procedures related to dedicated resources have to be performed towards the UE, they are initiated and driven by 3G_MSC-A. The 3G_MSC-A - 3G_MSC-B interface works as a 3G_MSC - RNS interface for the RANAP procedures. The Direct Transfer signalling is relayed transparently by 3G_MSC-B between 3G_MSC-A and the UE. During a successful relocation the order to perform location reporting at change of Service Area is not transferred to the target RNS. In the Intra-3G_MSC-A relocation case, the 3G_MSC-A re-issues the Location Reporting Control towards the target RNS. In the Inter-3G_MSC relocation case, 3G_MSC-A keeps the control of the Location Report Control procedure. However, re-issuing the Iu-LOCATION-REPORTING-CONTROL messages due to subsequent Intra3G_MSC-B relocations is the responsibility of 3G_MSC-B. 3GPP
  • 15. Release 1999 15 3GPP TS 23.009 V3.14.0 (2003-06) During a basic relocation, 3G_MSC-A initiates and controls all the relocation procedure, from its initiation (reception of Relocation Required from RNS-A on Iu-interface) until its completion (reception of Relocation Complete from 3G_MSC-B on E-interface). During a subsequent relocation back to 3G_MSC-A, 3G_MSC-A acts as an RNS towards 3G_MSC-B, which controls the relocation procedure until the termination in 3G_MSC-A of the handover radio resources allocation (sending of the Relocation Request Acknowledge to 3G_MSC-B from 3G_MSC-A). Then all relocation related messages shall terminate at 3G_MSC-A (e.g. Relocation Detect/Complete from RNS-B, Relocation Cancel from RNS-A). During a subsequent relocation to a third 3G_MSC, 3G_MSC-A works towards 3G_MSC-B' as described above in the basic relocation paragraph and towards 3G_MSC-B as described above in subsequent relocation paragraph. In the Inter-System, inter-3G_MSC handover case, 3G_MSC-A is the 3G_MSC which controls the call and the mobility management of the UE/MS during the call, before, during and after a basic or subsequent inter-system handover. When BSSAP procedures related to dedicated resources have to be performed towards the UE/MS, they are initiated and driven by 3G_MSC-A. The 3G_MSC-A – MSC-B interface works as a 3G_MSC – BSS interface for a subset of BSSMAP procedures. These BSSMAP procedures described in 3GPP TS 09 08 [7] are those related to dedicated resources. The DTAP signalling is relayed transparently by MSC-B between 3G_MSC-A and the UE/MS. During a basic inter-system UMTS to GSM handover, 3G_MSC-A initiates and controls all the handover procedure, from its initiation (reception of Relocation Required from RNS-A on Iu-interface) until its completion (reception of Handover Complete from MSC-B on E-interface). During a subsequent inter-system UMTS to GSM handover back to 3G_MSC-A, 3G_MSC-A acts as a BSS towards 3G_MSC-B, which controls the handover procedure until the termination in 3G_MSC-A of the handover radio resources allocation (sending of the Handover Request Acknowledge to 3G_MSC-B from 3G_MSC-A). Then all handover related messages shall terminate at 3G_MSC-A (e.g. Handover Detect/Complete from BSS-B, Relocation Cancel from RNS-A). During a subsequent inter-system UMTS to GSM handover to a third 3G_MSC, 3G_MSC-A works towards MSC-B' as described above in the basic inter-system handover paragraph and towards 3G_MSC-B as described above in subsequent inter-system handover paragraph. During a basic inter-system GSM to UMTS handover, 3G_MSC-A initiates and controls all the handover procedure, from its initiation (reception of Handover Required from BSS-A on A-interface) until its completion (reception of Handover Complete from 3G_MSC-B on E-interface). During a subsequent inter-system GSM to UMTS handover back to 3G_MSC-A, 3G_MSC-A acts as an RNS towards MSC-B, which controls the handover procedure until the termination in 3G_MSC-A of the handover radio resources allocation (sending of the Handover Request Acknowledge to MSC-B from 3G_MSC-A). Then all handover related messages shall terminate at 3G_MSC-A (e.g. Relocation Detect/Complete from RNS-B, Handover Failure from BSS-A). During a subsequent inter-system GSM to UMTS handover to a third 3G_MSC, 3G_MSC-A works towards 3G_MSC-B' as described above in the basic inter-system handover paragraph and towards MSC-B as described above in subsequent inter-system handover paragraph. 3G_MSC-A may assign a priority level defined as RAB parameter in 3GPP TS 25.413 [11] for each bearer. In case of relocation of a multicall configuration the 3G_MSC-B or the target RNC shall select the bearers to be handed over according to the priority level, if the target cell is not able to accommodate all bearers. If a selection has to be made between bearers of the same priority level, then the selection criteria are implementation dependent. If 3G_MSC-A supports the optional supplementary service Multicall (See 3GPP TS 23.135) and UE is engaged with multiple bearers the following description applies; - In the Intra-3G_MSC relocation case, the 3G-MSC-A tries to relocate all bearers to a new RNS. - In the basic relocation case, the 3G-MSC-A tries to relocate all bearers to 3G_MSC-B. If 3G_MSC-A receives an indication that the 3G_MSC-B does not support multiple bearers, then 3G_MSC-A shall be able to select one bearer to be handed over according to 3GPP TS 22.129 [9] and tries again to relocate the selected bearer. - In the subsequent relocation to a third 3G_MSC-B' case, the 3G-MSC-A tries to relocate all bearers to 3G_MSCB'. If 3G_MSC-A receives an indication that the 3G_MSC-B' does not support multiple bearers, then 3G_MSCA shall be able to select one bearer to be handed over according to 3GPP TS 22.129 [9] and tries again to relocate the selected bearer. 3GPP
  • 16. Release 1999 16 3GPP TS 23.009 V3.14.0 (2003-06) - In the Intra-3G_MSC inter-system UMTS to GSM handover case and the basic inter-system UMTS to GSM handover case, the 3G_MSC-A shall be able to select one bearer to be handed over according to 3GPP TS 22.129 [9] and tries to handover the selected bearer. - In all cases described above, 3G_MSC-A shall release some calls which has been carried by the bearers failed to set up in new RNS or the bearers not to be handed over. 4.3.2 Functional composition of 3G_MSC-A and its interfaces for handover/relocation In order to simplify the description of the handover/relocation procedures the controlling 3G_MSC (3G_MSC-A) can be considered to be composed of five functional units, as shown in figure 4. Signalling functions 1) RNC/BSC/3G_MSC (UE/MS/RNC/BSC) Procedures 3G_MSC-A. This unit is used to control the signalling between the 3G_MSC, RNC or BSC and UE/MS. Interface Iu' is the connection to the old RNC and interface Iu'' is the connection to the new RNC, when an Intra-3G_MSC relocation takes place. Interface Iu' is the connection to the old RNC and interface A'' is the connection to the new BSC, when an Intra-3G_MSC UMTS to GSM handover takes place. Interface A' is the connection to the old BSC and interface Iu'' is the connection to the new RNC, when an Intra-3G_MSC GSM to UMTS handover takes place. Interface x represents the interworking connection to the Handover/Relocation Control Procedures 3G_MSC-A. 2) Call Control Procedures 3G_MSC-A. This unit is used to control the call. Interface B' is used for normal call control procedures. When a Basic relocation from 3G_MSC-A to 3G_MSC-B is to be performed then interface B'' is employed to provide a signalling and call control connection to 3G_MSC-B. If a Subsequent handover/relocation to 3G_MSC-B' is to be performed then interface B''' is used. Similarly, when a Basic intersystem handover from 3G_MSC-A to 3G_MSC-B is to be performed, then interface B'' is employed to provide a signalling and call control connection to 3G_MSC-B. If a Subsequent inter-system handover to 3G_MSC-B' is to be performed then interface B''' is used. 3) Handover/Relocation Control Procedures 3G_MSC-A. This unit provides both the overall control of the handover/relocation procedure and interworking between the internal interfaces (x, y and z). 4) MAP Procedures 3G_MSC-A. This unit is responsible for controlling the exchange of MAP messages between 3G_MSCs during an Inter-3G_MSC handover/relocation, or between 3G_MSC-A and MSC-B during an Intersystem Inter-3G_MSC handover. This unit communicates with the Handover/Relocation Control Procedures 3G_MSC-A via interface z. Switching functions 5) Switch and Handover/Relocation Device 3G_MSC-A. For all calls this unit is responsible for connecting the new path into the network via interface B'. In specific cases it may be unnecessary to take any explicit action in the 3G_MSC concerning the handover/relocation device. The handover/relocation device interconnections are illustrated in figure 5. 3GPP
  • 17. Release 1999 17 Signalling functions 2 3GPP TS 23.009 V3.14.0 (2003-06) Call Control Procedures 3G MSC-A y Iu’/A’ RNC/BSC/ 3G_MSC (UE/MS/RNC/BSC) Procedures 1 Iu’’/A’’ 3 x B’ B’’ B’’’ HO/Rel Control Procedures 3G MSC-A z 4 MAP Procedures 3G_MSC-A C Switching control Iu’/A’ Switching functions 5 Iu’’/A’’ B’ Switch and HO/Rel Device 3G MSC-A B’’ B’’’ Figure 4: Functional composition of the controlling 3G_MSC (3G_MSC-A) for supporting handover/relocation For UE/MS to UE/MS calls in the same 3G_MSC the configuration in figure 5b) applies. In this case interface B'' is internal to 3G_MSC-A and does not connect to another 3G_MSC. The handover/relocation device can be either a three-party bridge or a switching facility without three-party connection capabilities. For a three-party bridge configuration the states of the handover/relocation device are as shown in table 2. The three-party configuration exists in the intermediate state. This type of handover/relocation device may reduce the interruption time. However, this may require noise reduction if one of the radio channels is unterminated at some time in the intermediate state. For a handover/relocation device consisting of a simple switch there will be no intermediate state. Table 2: States of the handover/relocation device Resulting Connection Successful Unsuccessful Procedure Procedure B' to Iu'' B' to Iu' B' to A'' B' to Iu' B' to Iu'' B' to A' Case Initial Connection Intermediate Connection Figure 5a) B' to Iu' B' to Iu' B' to A' B' to Iu' and Iu'' B' to Iu' and A'' B' to A' and Iu'' Figure 5b) B' to Iu' B' to Iu' and B'' B' to B'' B' to Iu' Figure 5c) B' to B'' B' to B''and B''' B' to B''' B' to B'' 3GPP
  • 18. Release 1999 18 3GPP TS 23.009 V3.14.0 (2003-06) B’ Iu’/A’ Iu’’/A’’ a) Intra-3G_MSC Handover/Relocation case. B’ Iu’ B’’ b) Basic Handover/Relocation case and handover/relocation of UE/MS to UE/MS call in the same 3G_MSC. B’ B’’ B’’’ c) Subsequent Handover/Relocation case NOTE: In a) and b) Iu’ is released after handover/relocation; In c) B’’ is released after handover/relocation. Figure 5: Connections in the handover/relocation device (Unit 5) 4.4 3G_MSC-B For roles and functional composition of the 3G_MSC-B working as pure GSM MSC, please see previous clause ("MSC-B"). 4.4.1 Role of 3G_MSC-B In the Intra-3G_MSC handover/relocation case, the 3G_MSC-B keeps the control of the whole Intra-3G_MSC handover/relocation procedure. 3G_MSC-B notifies MSC-A or 3G_MSC-A of intra-3G_MSC-B InterSystem handover and intra GSM handovers, by using the A-HANDOVER-PERFORMED message. In case of intra-3G_MSC-B SRNS relocation, if security algorithms have been changed then: a) When encapsulated BSSAP is used on the E interface, the A-HANDOVER-PERFORMED message shall be sent. b) When encapsulated RANAP is used on the E interface, the Iu-LOCATION-REPORT message shall be sent. On reception of an order to perform location reporting at change of Service Area from 3G_MSC-A, 3G_MSC-B shall be responsible to re-issue the Iu-LOCATION-REPORTING-CONTROL message after subsequent Intra-3G_MSC-B relocations/handovers. This shall be performed immediately after the successful completion of the Relocation Resource Allocation procedure. In both cases, the selected UMTS algorithm(s) shall be indicated in the MAP-PROCESS-ACCESS-SIGNALLING request. The role of 3G_MSC-B is also to provide transcoder resources. In the Inter-3G_MSC relocation case, the role of 3G_MSC-B (3G_MSC-B') is only to provide radio resources control within its area. This means that 3G_MSC-B keeps control of the radio resources connection and release towards RNS-B. 3G_MSC-B will do some processing on the RANAP information received on the E-interface or the RANAP information received on the Iu-interface whereas it will relay the Direct Transfer information transparently between 3GPP
  • 19. Release 1999 19 3GPP TS 23.009 V3.14.0 (2003-06) Iu-interface and E-interface. 3G_MSC-A initiates and drives RANAP procedures towards 3G_MSC-B, while 3G_MSC-B controls them towards its RNSs to the extent that 3G_MSC-B is responsible for the connections of its RNSs. The release of the dedicated resources between 3G_MSC-B and RNS-B is under the responsibility of 3G_MSC-B and RNS-B, and is not directly controlled by 3G_MSC-A. When clearing is to be performed due to information received from RNS-B, 3G_MSC-B shall transfer this clearing indication to 3G_MSC-A, to clear its connection with RNS-B, to terminate the dialogue with 3G_MSC-A through the E-interface, and to release its circuit connection with 3G_MSC-A, if any. In the same way, the release of the connection to its RNS-B, is initiated by 3G_MSC-B, when the dialogue with 3G_MSC-A ends normally and a release is received from the circuit connection with 3G_MSC-A, if any, or when the dialogue with the 3G_MSC-A ends abnormally. When a release is received by 3G_MSC-B for the circuit connection with 3G_MSC-A then 3G_MSC-B shall release the circuit connection. In the Inter-system UMTS to GSM Inter-3G_MSC handover case, the role of 3G_MSC-B (3G_MSC-B') is only to provide radio resources control within its area. This means that 3G_MSC-B keeps control of the radio resources connection and release towards BSS-B. 3G_MSC-B will do some processing on the BSSMAP information received on the E-interface or the BSSMAP information received on the A-interface whereas it will relay the DTAP information transparently between A-interface and E-interface. 3G_MSC-A initiates and drives a subset of BSSMAP procedures towards 3G_MSC-B, while 3G_MSC-B controls them towards its BSSs to the extent that 3G_MSC-B is responsible for the connections of its BSSs. The release of the dedicated resources between 3G_MSC-B and BSS-B is under the responsibility of 3G_MSC-B and BSS-B, and is not directly controlled by 3G_MSC-A. When clearing is to be performed due to information received from BSS-B, 3G_MSC-B shall transfer this clearing indication to 3G_MSC-A, to clear its connection with BSS-B, to terminate the dialogue with 3G_MSC-A through the E-interface, and to release its circuit connection with MSC-A, if any. In the same way, the release of the connection to its BSS-B, is initiated by 3G_MSC-B, when the dialogue with 3G_MSC-A ends normally and a release is received from the circuit connection with 3G_MSC-A, if any, or when the dialogue with the MSC-A ends abnormally. When a release is received by 3G_MSC-B for the circuit connection with 3G_MSC-A then 3G_MSC-B shall release the circuit connection. In the Inter-system GSM to UMTS Inter-3G_MSC handover case, the role of 3G_MSC-B (3G_MSC-B') is only to provide radio resources control within its area. This means that 3G_MSC-B keeps control of the radio resources connection and release towards RNS-B. 3G_MSC-B will do some processing on the BSSMAP information received on the E-interface or the RANAP information received on the Iu-interface whereas it will relay the Direct Transfer information transparently between Iu-interface and E-interface. MSC-A initiates and drives a subset of BSSMAP procedures towards 3G_MSC-B, while 3G_MSC-B controls them towards its RNSs to the extent that 3G_MSC-B is responsible for the connections of its RNSs. The release of the dedicated resources between 3G_MSC-B and RNS-B is under the responsibility of 3G_MSC-B and RNS-B, and is not directly controlled by MSC-A. When clearing is to be performed due to information received from RNS-B, 3G_MSC-B shall transfer this clearing indication to MSC-A, to clear its connection with RNS-B, to terminate the dialogue with MSC-A through the E-interface, and to release its circuit connection with MSC-A, if any. In the same way, the release of the connection to its RNS-B, is initiated by 3G_MSC-B, when the dialogue with MSC-A ends normally and a release is received from the circuit connection with MSC-A, if any, or when the dialogue with the MSC-A ends abnormally. When a release is received by 3G_MSC-B for the circuit connection with MSC-A then 3G_MSC-B shall release the circuit connection. At intra-PLMN handover/relocation, 3G_MSC-B shall send Service Handover related information to the BSC/RNC if and only if this Service Handover information is received from 3G_MSC-A. 3G_MSC-B shall not modify Service Handover related information received from a 3G_MSC-A within the same PLMN. If 3G_MSC-B does not support the optional supplementary service Mutlicall (See 3GPP TS 23.135) and 3G_MSC-A requests to relocate multiple bearers, 3G_MSC-B shall indicate that it does not support multiple bearers to 3G_MSC-A. If 3G_MSC-B supports the optional supplementary service Multicall (See 3GPP TS 23.135) and UE is engaged with multiple bearers the following description applies; - In the basic relocation case, the 3G_MSC-B shall be able to allocate a Handover Number for each bearer. The 3G_MSC-B shall also be able to select some bearers to be handed over according to the priority level defined as RAB parameters in 3GPP TS 25.413 [11] so that the number of bearers will fulfill the maximum number of bearers supported by the 3G_MSC-B. If a selection has to be made between bearers of the same priority level, then the selection criteria are implementation dependent. - In the Intra-3G_MSC relocation case, the 3G_MSC-B tries to relocate all bearers to a new RNS. 3GPP
  • 20. Release 1999 20 3GPP TS 23.009 V3.14.0 (2003-06) - In the subsequent relocation back to the 3G_MSC-A or to a third 3G_MSC-B' case, the 3G_MSC-B tries to request to the 3G_MSC-A to relocate all bearers to the 3G_MSC-A or to the 3G_MSC-B'. - In the Intra-3G_MSC inter-system UMTS to GSM handover case and the subsequent inter-system UMTS to GSM handover back to the 3G_MSC-A or to a third MSC-B' case, the 3G_MSC-B shall be able to select one bearer to be handed over according to 3GPP TS 22.129 [9] and tries to handover the selected bearer. 4.4.2 Functional composition of 3G_MSC-B and its interfaces for handover/relocation The functional composition of a 3G_MSC acting as 3G_MSC-B is essentially the same as that of 3G_MSC-A. However, there are some differences. The functional units are as follows (see figure 6). Signalling functions 1) RNC/BSC/3G_MSC (UE/MS/RNC/BSC) Procedures 3G_MSC-B. This unit is used to control the signalling between the 3G_MSC, RNC, BSC and UE/MS. Interface Iu' is the connection to the old RNC and interface Iu'' is the connection to the new RNC, when an Intra-3G_MSC relocation takes place. Interface Iu' is the connection to the old RNC and interface A'' is the connection to the new BSC, when an Intra-3G_MSC UMTS to GSM handover takes place. Interface A' is the connection to the old BSC and interface Iu'' is the connection to the new RNC, when an Intra-3G_MSC GSM to UMTS handover takes place. Interface x represents the interworking connection to the Handover/Relocation Control Procedures 3G_MSC-B. 2) Call Control Procedures 3G_MSC-B. This unit is used for normal call control and signalling to 3G_MSC-A or MSC-A in the case of inter-system inter-3G_MSC handover. 3) Handover/Relocation Control Procedures 3G_MSC-B. This unit provides both the overall control of the handover/relocation procedure and interworking between the internal interfaces (x, y and z) in 3G_MSC-B. 4) MAP Procedures 3G_MSC-B. This unit is responsible for controlling the exchange of MAP messages between 3G_MSC-A, or MSC-A, and 3G_MSC-B and for signalling to the VLR in 3G_MSC-B. Switching functions 5) Switch 3G_MSC-B. For all calls this unit is responsible, with RNS-B, for connecting the circuit from 3G_MSC-A, or MSC-A, to RNS-B. This unit may also need to act as a handover/relocation device for Intra3G_MSC handovers/relocation controlled by 3G_MSC-B. In specific cases it may be unnecessary to take any explicit action in the 3G_MSC concerning the handover/relocation device. 3GPP
  • 21. Release 1999 21 Signalling functions 2 3GPP TS 23.009 V3.14.0 (2003-06) Call Control Procedures 3G MSC-B B’’ y Iu’/A’ RNC/BSC/ 3G_MSC (UE/MS/RNC/BSC) Procedures 1 Iu’’/A’’ 3 x HO/Rel Control Procedures 3G MSC-B z 4 MAP Procedures 3G_MSC-B C Switching control Iu’/A’ Switching functions 5 Switch 3G_MSC-B B’’ Iu’’/A’’ Figure 6: Functional composition of 3G_MSC-B for supporting handover/relocation 5 Handover initiation conditions Handover may be initiated by the network based on RF criteria as measured by the MS or the Network (signal level, Connection quality, power level propagation delay) as well as traffic criteria (e.g. current traffic loading per cell, interference levels, maintenance requests, etc.). In order to determine if a handover is required, due to RF criteria, it is typically the MS that shall take radio measurements from neighbouring cells. These measurements are reported to the serving cell on an event driven or regular basis. When a network determines a need for executing a handover the procedures given in 3GPP TS 08.08 [5], 3GPP TS 25.303 [13], 3GPP TS 25.331 [14] are followed. The decision process used to determine when to perform soft handover or hard handover will typically differ. Depending on the support for soft or hard handover the Intra-MSC and Inter-MSC handover may differ. In the case of an ongoing GSM voice group call (see 3GPP TS 03.68 [3]) the criteria described above shall only apply to the mobile station currently assigned the uplink and other users with a dedicated connection, no actions shall be taken for the listening users. 3GPP
  • 22. Release 1999 6 22 3GPP TS 23.009 V3.14.0 (2003-06) General description of the procedures for intra - MSC handovers This clause gives a brief overview of the procedures that shall be followed when performing Intra-MSC handovers. Detailed explanation of these procedures can be found in 3GPP TS 08.08 [5] and 3GPP TS 24.008 [10]. There are two types of handover that can be considered which involve a BSS and single MSC. These are Internal Handover and External Handover. An Internal Handover is a handover which takes place between channels on a cell or cells controlled by a single BSS, without reference to the MSC, although the MSC maybe informed of its occurrence. This case is not considered in the present document. Handovers between channels on the same cell or between cells on the same BSS which are controlled by the MSC are termed External Handovers and use identical procedures to those for Intra-MSC handovers. Only the Intra-MSC handover case will be considered in the present document. Handovers from a BSS to an RNS controlled by the same 3G_MSC are intra-3G_MSC GSM to UMTS handovers. Handovers from an RNS to a BSS controlled by the same 3G_MSC are intra-3G_MSC UMTS to GSM handovers. There are two types of handover in UMTS: soft handover and hard handover. The first one is fully performed within UTRAN, without involving the core network. The second one may be also performed within UTRAN, or the core network may be involved if the Iur interface between RNSs does not exist. This case of hard handover involving the core network is the only one that is covered in the present document, together with SRNS relocation with Iur interface. 6.1 Procedure for Intra-MSC Handovers The procedure for a successful External Intra-MSC handover is shown in figure 7. It is assumed that selection of a candidate MS has already taken place within the BSS based upon the criteria presented in clause 5. The exact algorithm, in the BSS, for determining a candidate MS is not addressed in the present document. The procedures discussed do not make use of the Mobile Application Part (MAP), represented by signalling function 4 in figure 2 and figure 3. The procedure described in this subclause covers case i). MS MS BSS-A MSC-A BSS-B A-Handover-Required A-Handover-Request A-Handover-Request-Ack A-Handover-Command RI-HO-Command RI-HO-Access A-Handover-Detect RI-HO-Complete A-Handover-Complete A-Clear-Command A-Clear-Complete Figure 7: Basic External Intra-MSC Handover Procedure 3GPP
  • 23. Release 1999 23 3GPP TS 23.009 V3.14.0 (2003-06) The successful operation of the procedure is as follows. When the BSS (BSS-A), currently supporting the MS, determines that the MS requires to be handed over it will send an A-HANDOVER-REQUIRED message to the MSC (MSC-A). The A-HANDOVER-REQUIRED message shall contain a list of cells, or a single cell, to which the MS can be handed over. The list of cells shall be given in order of preference based upon operator determined criteria (These criteria are not addressed within the present document and are operator dependent). When the MSC-A receives the AHANDOVER-REQUIRED message it shall begin the process of handing over the MS to a new BSS (BSS-B). (NOTE: BSS-A and BSS-B maybe the same BSS). The MSC-A shall generate an A-HANDOVER-REQUEST message to the selected BSS (BSS-B). When BSS-B receives the A-HANDOVER-REQUEST message it shall take the necessary action to allow the MS to access the radio resource of BSS-B, this is detailed in 3GPP TS 08.58 [6] and in 3GPP TS 05.08 [4]. The switching of the radio resource through the necessary terrestrial resources is detailed in 3GPP TS 24.008 [10] and 3GPP TS 08.08 [5]. Once resource allocation has been completed by BSS-B it shall return an A-HANDOVER-REQUEST-ACK. to MSC-A. When this message is received by MSC-A it shall begin the process of instructing the MS to tune to a new dedicated radio resource. An A-HANDOVER-COMMAND will be sent by the MSC-A to BSS-A. On receipt of the AHANDOVER-COMMAND message BSS-A will send the radio interface message RI-HANDOVER-COMMAND, containing a Handover Reference number previously allocated by BSS-B, to the MS. The MS will then access the new radio resource using the Handover Reference number contained in the RI-HANDOVER-ACCESS message. The number will be checked by BSS-B to ensure it is as expected and the correct MS has been captured. If this is the correct MS then the BSS-B shall send an A-HANDOVER-DETECT to MSC-A. When the MS is successfully communicating with the BSS-B a RI-HANDOVER-COMPLETE message will be sent by the MS to BSS-B. The BSS-B will then send an A-HANDOVER-COMPLETE message to MSC-A. NOTE: The A-HANDOVER-REQUEST-ACK from BSS-B contains the complete Radio Interface message that shall be sent by BSS-A to the MS in the RI-HANDOVER-COMMAND, MSC-A transparently passes this radio interface message onto BSS-A. After MSC-A has received the A-HANDOVER-COMPLETE message from BSS-B it shall begin to release the resources allocated on BSS-A. In figure 7 the resource is released by using the A-CLEAR-COMMAND sequence. In the case of ongoing GSM voice group calls the clearing of resources on BSS-A shall not be used if the resources are still be used on the down link. If a failure occurs during the handover attempt, for example A-HANDOVER-FAILURE returned from BSS-A or BSSB, then MSC-A will terminate the handover to BSS-B. Under these conditions MSC-A may optionally take one of a number of actions: i) retry the handover to the same cell; ii) select the next cell from the list contained in the A-HANDOVER-REQUIRED message and attempt a handover to the new cell; iii) await the next A-HANDOVER-REQUIRED message; iv) send an A-HANDOVER-REQUIRED-REJECT to BSS-A, if an A-HANDOVER-COMMAND has not already been sent. The exact action taken is dependent on whether the failure occurs before or after the A-HANDOVER-COMMAND has been sent. In all cases the existing connection to the MS shall not be cleared except in the case of expiry of the timer for receipt of A-HANDOVER-COMPLETE. During the period that the MS is not in communication with the network MSC-A shall queue all appropriate messages. All messages shall be delivered to the MS once communication is resumed . In the case of an Intra-MSC handover on MSC-B then the messages shall be queued by MSC-B. In the case of ongoing GSM voice group calls if a failure occurs when handing over a user on a dedicated channel then the procedures described above may optionally be applied. 3GPP
  • 24. Release 1999 24 3GPP TS 23.009 V3.14.0 (2003-06) 6.2 Procedure for Intra-3G_MSC Handovers 6.2.1 Intra-3G_MSC Handover from UMTS to GSM The procedure for a successful Intra-3G_MSC handover from UMTS to GSM is shown in figure 8. It is assumed that selection of a candidate UE/MS has already taken place within the RNS based upon the criteria presented in clause 5. The exact algorithm, in the RNS, for determining a candidate UE/MS is not addressed in the present document. The procedures discussed do not make use of the Mobile Application Part (MAP), represented by signalling function 4 in figures 4 and 6. The procedure described in this subclause covers case ii). UE/MS UE/MS RNS-A 3G_MSC-A BSS-B Iu-Relocation-Required A-Handover-Request A-Handover-Request-Ack Iu-Relocation-Command RRC-HO-Command RI-HO-Access A-Handover-Detect RI-HO-Complete A-Handover-Complete Iu-Release-Command Iu-Release-Complete Figure 8: Basic Intra-3G_MSC 6.2.1.1 Handover from UMTS to GSM Procedure With no bearer or one bearer The successful operation of the procedure is as follows. When the RNS (RNS-A), currently supporting the UE/MS, determines that the UE/MS requires to be handed over to GSM it will send an IU-RELOCATION-REQUIRED message to the 3G_MSC (3G_MSC-A). The IU-RELOCATION-REQUIRED message shall contain a single cell, to which the UE/MS can be handed over. When the 3G_MSC-A receives the IU-RELOCATION-REQUIRED message it shall begin the process of handing over the UE/MS to a BSS (BSS-B). The 3G_MSC-A shall generate an A-HANDOVERREQUEST message to the selected BSS (BSS-B). When BSS-B receives the A-HANDOVER-REQUEST message it shall take the necessary action to allow the UE/MS to access the radio resource of BSS-B, this is detailed in 3GPP TS 08.58 [6] and in 3GPP TS 05.08 [4]. The switching of the radio resource through the necessary terrestrial resources is detailed in 3GPP TS 24.008 [10] and 3GPP TS 08.08 [5]. Once resource allocation has been completed by BSS-B it shall return an A-HANDOVER-REQUEST-ACK. to 3G_MSC-A. When this message is received by 3G_MSC-A it shall begin the process of instructing the UE/MS to tune to a new dedicated radio resource. An IU-RELOCATION-COMMAND will be sent by the 3G_MSC-A to RNS-A. On receipt of the IU-RELOCATION-COMMAND message RNS-A will send the radio resource control message RRCHANDOVER-COMMAND, containing a Handover Reference number previously allocated by BSS-B, to the UE/MS. The UE/MS will then access the new radio resource using the Handover Reference number contained in the RIHANDOVER-ACCESS message. The number will be checked by BSS-B to ensure it is as expected and the correct UE/MS has been captured. If this is the correct UE/MS then the BSS-B shall send an A-HANDOVER-DETECT to 3G_MSC-A. When the UE/MS is successfully communicating with the BSS-B a RI-HANDOVER-COMPLETE message will be sent by the UE/MS to BSS-B. The BSS-B will then send an A-HANDOVER-COMPLETE message to 3G_MSC-A. NOTE: The A-HANDOVER-REQUEST-ACK from BSS-B contains the complete radio resource control message that shall be sent by RNS-A to the UE/MS in the RRC-HANDOVER-COMMAND, 3G_MSC-A transparently passes this radio interface message onto RNS-A. 3GPP
  • 25. Release 1999 25 3GPP TS 23.009 V3.14.0 (2003-06) After 3G_MSC-A has received the A-HANDOVER-COMPLETE message from BSS-B it shall begin to release the resources allocated on RNS-A. In figure 8 the resource is released by using the IU-RELEASE-COMMAND sequence. If a failure occurs during the handover attempt, for example A-HANDOVER-FAILURE returned from BSS-B, then 3G_MSC-A will terminate the handover to BSS-B and send an IU-RELOCATION-PREPARATION-FAILURE message to RNS-A. If RNS-A has decided to cancel the handover, it sends IU-RELOCATION-CANCEL message to 3G_MSC-A. The 3G_MSC-A will then terminate the handover towards BSS-B (if initiated) and send IU-RELOCATION-CANCELACKNOWLEDGE message to RNS-A. In all cases the existing connection to the UE/MS shall not be cleared except in the case of expiry of the timer for receipt of A-HANDOVER-COMPLETE. During the period that the UE/MS is not in communication with the network 3G_MSC-A shall queue all appropriate messages. All messages shall be delivered to the UE/MS once communication is resumed. In the case of an Intra3G_MSC handover from UMTS to GSM on 3G_MSC-B then the messages shall be queued by 3G_MSC-B. 6.2.1.2 With multiple bearers (Optional functionality) If 3G_MSC-A supports the optional supplementary service Multicall (See 3GPP TS 23.135), 3G_MSC-A shall have the following functionality additionally to the description in section 6.2.1.1. Upon receipt of the IU-RELOCATION-REQUIRED from RNS-A 3G_MSC-A shall select one bearer to be handed over if the UE is engaged with multiple bearers. After that, 3G_MSC-A generates an A-HO-REQUEST message for the selected bearer to BSS-B. When an A-HO-REQUEST-ACK is received from BSS-B, 3G_MSC-A sends IU-RELOCATION-COMMAND, which indicates the bearers not to be handed over as bearers to be released, to RNS-A. After 3G_MSC-A receives A-HO-COMPLETE message from BSS-B, 3G_MSC-A shall release calls via BSS-B, which has been carried by the bearers not to be handed over, and then sends IU-RELEASE-COMMAND to RNS-A. 6.2.2 Intra-3G_MSC GSM to UMTS Handover The procedure for a successful Intra-3G_MSC handover is shown in figure 9. It is assumed that selection of a candidate UE/MS has already taken place within the BSC based upon the criteria presented in clause 5. The exact algorithm, in the BSC, for determining a candidate UE/MS is not addressed in the present document. The procedures discussed do not make use of the Mobile Application Part (MAP), represented by signalling function 4 in figures 4 and 6. The procedure described in this subclause covers case ii). In case of subsequent handover the following applies. If 3G_MSC-B supports location reporting at change of Service Area and if encapsulated BSSAP signalling is used on the E-interface, 3G_MSC-B shall always initiate the Location Reporting Control procedure at change of Service Area towards the target RNS since no request for Location Reporting can be received from MSC-A. In that case, the Location Reporting Control procedure shall be initiated by 3G_MSC-B after the Relocation Resource Allocation procedure has been executed successfully. The change of Service Area shall be reported to MSC-A within an A-HANDOVER-PERFORMED message. In the case of ongoing voice group calls, the handover does not take place since voice group calls are not supported in UMTS. 3GPP
  • 26. Release 1999 26 3GPP TS 23.009 V3.14.0 (2003-06) UE/MS UE BSS-A 3G MSC-A RNS-B A-Handover-Required Iu-Relocation-Request Iu-Relocation-Request-Ack A-Handover-Command RI-HO-Command Iu-Relocation-Detect RRC-HO-Complete Iu-Relocation-Complete A-Clear-Command A-Clear-Complete Figure 9: Basic External Intra-3G_MSC GSM to UMTS Handover Procedure The successful operation of the procedure is as follows. When the BSS (BSS-A), currently supporting the UE, determines that the UE requires to be handed over to UMTS it will send an A-HANDOVER-REQUIRED message to the 3G_MSC (3G_MSC-A). The A-HANDOVER-REQUIRED message shall contain a single cell, to which the UE can be handed over. When the 3G_MSC-A receives the A-HANDOVER-REQUIRED message it shall begin the process of handing over the UE to a new RNS (RNS-B). The 3G_MSC-A shall generate an Iu-RELOCATION-REQUEST message to the selected RNS (RNS-B). When RNS-B receives the Iu-RELOCATION-REQUEST message it shall take the necessary action to allow the UE to access the radio resource of RNS-B, this is detailed in the 3GPP TS 25.300 series and the 3GPP TS 25.200 series of Technical Specifications. The switching of the radio resource through the necessary terrestrial resources is detailed in the 3GPP TS 25.430 series and 3GPP TS 25.413 [11]. Once resource allocation has been completed by RNS-B, it shall return an Iu-RELOCATION-REQUEST-ACK. to 3G_MSC-A. When this message is received by 3G_MSC-A it shall begin the process of instructing the UE to tune to a new dedicated radio resource. An A-HANDOVER-COMMAND will be sent by the 3G_MSC-A to BSS-A. On receipt of the A-HANDOVER-COMMAND message BSS-A will send the radio interface message RI-HANDOVERCOMMAND. The UE will then access the new radio resource. On detection of the UE, the RNS-B shall send an IuRELOCATION-DETECT to 3G_MSC-A. When the UE is successfully communicating with the RNS-B an RRCHANDOVER-COMPLETE message will be sent by the UE to RNS-B. The RNS-B will then send an IuRELOCATION-COMPLETE message to 3G_MSC-A. NOTE: The Iu-RELOCATION-REQUEST-ACK from RNS-B contains the complete RRC message that shall be sent by BSS-A to the MS in the RI-HANDOVER-COMMAND, 3G_MSC-A transparently passes this radio interface message onto BSS-A. After 3G_MSC-A has received the Iu-RELOCATION-COMPLETE message from RNS-B, it shall begin to release the resources allocated on BSS-A. In figure 9 the resource is released by using the A-CLEAR-COMMAND sequence. If a failure occurs during the handover attempt, for example, A-HANDOVER-FAILURE returned from BSS-A or Iu-RELOCATION FAILURE returned from RNS-B, then 3G_MSC-A will terminate the handover to RNS-B. Under these conditions 3G_MSC-A may optionally take one of a number of actions: i) await the next A-HANDOVER-REQUIRED message; ii) send an A-HANDOVER-REQUIRED-REJECT to BSS-A, if an A-HANDOVER-COMMAND has not already been sent. The exact action taken is dependent on whether the failure occurs before or after the A-HANDOVER-COMMAND has been sent. In all cases the existing connection to the UE shall not be cleared except in the case of expiry of the timer for receipt of Iu-RELOCATION-COMPLETE. 3GPP
  • 27. Release 1999 27 3GPP TS 23.009 V3.14.0 (2003-06) During the period that the UE is not in communication with the network 3G_MSC-A shall queue all appropriate messages. All messages shall be delivered to the UE once communication is resumed. In the case of an Intra-3G_MSC GSM to UMTS handover on 3G_MSC-B then the messages shall be queued by 3G_MSC-B. 6.2.3 Procedure for Intra-3G_MSC SRNS Relocation The procedure for a successful Intra-3G_MSC SRNS Relocation is shown in figures 10 and 11. SRNS Relocation is used to relocate the serving RNS functionality from one RNS to another. The procedure may or may not involve change of the radio resources assigned for the corresponding UE. Whether or not the Relocation includes change of radio resources assigned for the UE does not affect the SRNS Relocation procedure in the Core Network. In case of subsequent Intra-3G_MSC-B SRNS relocation the following applies: - If 3G_MSC-B has previously received an order to perform location reporting at change of Service Area from 3G_MSC-A and if 3G_MSC-B also supports Location Reporting Control, it shall issue the Iu-LOCATIONREPORTING-CONTROL message towards the target RNS immediately after successful completion of relocation. Upon receipt of Iu-LOCATION-REPORT, 3G_MSC-B shall forward it towards 3G_MSC-A via E interface. - If 3G_MSC-B supports location reporting at change of Service Area and if encapsulated BSSAP signalling is used on the E-interface, 3G_MSC-B shall always initiate the Location Reporting Control procedure at change of Service Area towards the target RNS, since no request for Location Reporting can be received from MSC-A. In that case the Location Reporting Control procedure shall be initiated by 3G_MSC-B after the Relocation Resource Allocation procedure has been executed successfully. The change of Service Area shall be reported to MSC-A within an A-HANDOVER-PERFORMED message. It is assumed that selection of a candidate UE has already taken place within RNS based upon the criteria presenting in clause 5. The exact algorithm, in RNS, for determining a candidate UE is not addressed in the present document. The procedure discussed does not make use of the Mobile Application Part (MAP), represented by signalling function 4 in figures 4 and 6. The procedure described in this subclause covers case ii). UE UE RNS-A 3G_MSC-A RNS-B Iu-Relocation-Required Iu-Relocation-Request Iu-Relocation-Request-Ack Iu-Relocation-Command Iur-SRNC-Relocation-Commit Iu-Relocation-Detect Iu-Relocation-Complete Iu- Release-Command Iu- Release-Complete Figure 10 Basic intra-3G_MSC SRNS Relocation Procedure 3GPP
  • 28. Release 1999 28 3GPP TS 23.009 V3.14.0 (2003-06) UE UE RNS-A 3G_MSC-A RNS-B Iu-Relocation-Required Iu-Relocation-Request Iu-Relocation-Request-Ack Iu-Relocation-Command Detection of UE in target RNS RR-HO-Command Iu-Relocation-Detect RR-HO-Complete Iu-Relocation-Complete Iu- Release-Command Iu- Release-Complete Figure 11 Basic intra-3G_MSC SRNS Relocation Procedure combined with hard change of radio resources (Hard Handover with switch in the Core Network) 6.2.3.1 With no bearer or one bearer The successful operation of the procedure is as follows. When the Serving RNS (RNS-A) makes the decision to perform the SRNS Relocation procedure it will send an IU-RELOCATION-REQUIRED message to the 3G_MSC (3G_MSC-A). The IU-RELOCATION-REQUIRED message shall contain the identifier of the target RNS to which the Relocation is to be performed. When the 3G_MSC-A receives the IU-RELOCATION-REQUIRED message it shall begin the process of relocating the serving RNS functionality to the new RNS (RNS-B). The 3G_MSC-A shall generate an IURELOCATION-REQUEST message to the selected RNS (RNS-B). When RNS-B receives the IU-RELOCATIONREQUEST message it shall take the necessary action to establish the new Iu transport bearers for each Radio Access Bearer related to 3G_MSC-A for the UE in question, this is detailed in the 3GPP TS 25.430 series and 3GPP TS 25.413 [11]. Once resource allocation has been completed by RNS-B it shall return an IU-RELOCATION-REQUESTACKNOWLEDGE to 3G_MSC-A. When this message is received by 3G_MSC-A, and 3G_MSC-A is ready for the move in Serving RNS functionality, it shall indicate the completion of the preparation phase on the core network side for the SRNS Relocation. An IU-RELOCATION-COMMAND message is sent by 3G_MSC-A to RNS-A. RNS-A acts as follows: i) if the procedure is a SRNS Relocation without change of radio resources, which means that the Iur interface between RNS-A and RNS-B can be used for the procedure, the RNS-A shall send IUR-SRNS-RELOCATIONCOMMIT message to the RNS-B to trigger the Relocation execution. See figure 10. ii) if the procedure is a SRNS Relocation with change of radio resources, which means that the Iur interface between RNS-A and RNS-B is not used for the procedure, the RNS-A shall trigger the handover procedure on the air interface by sending the RRC-HANDOVER-COMMAND to the UE. The UE will then access the new radio resources. See figure 11. NOTE: The IU-RELOCATION-REQUEST-ACKNOWLEDGE from RNS-B may optionally contain a transparent container, which is transferred by 3G_MSC-A to the RNS-A using the IU-RELOCATION-COMMAND message. When the relocation execution trigger is received, RNS-B shall then take the necessary action to assume the role of Serving RNS and shall send an IU-RELOCATION-DETECT message to 3G_MSC-A. When the UE is successfully in communication with the RNS-B, then RNS-B shall send an IU-RELOCATION-COMPLETE message to 3G_MSC-A. After 3G_MSC-A has received the IU-RELOCATION-COMPLETE message from RNS-B, it shall begin to release the resources associated to the RNS-A. In figures 10 and 11, the resources are released by using the IU-RELEASE-COMMAND sequence. 3GPP
  • 29. Release 1999 29 3GPP TS 23.009 V3.14.0 (2003-06) If a failure occurs during the SRNS Relocation attempt, then 3G_MSC-A will terminate the relocation to RNS-B. For example, if IU-RELOCATION-FAILURE is returned from RNS-B then 3G_MSC-A will terminate the relocation to RNS-B and send IU-RELOCATION-PREPARATION-FAILURE to RNS-A. If IU-RELOCATION-CANCEL is returned from RNS-A, then 3G_MSC-A will terminate the relocation to RNS-B and send IU-RELOCATIONCANCEL-ACKNOWLEDGE to RNS-A. In all cases the existing connection to the UE shall not be cleared except in the case of expiry of the timer for receipt of Iu-RELOCATION-COMPLETE. During the period that the UE is not in communication with the network, 3G_MSC-A shall queue all appropriate messages. All messages shall be delivered to the UE once communication is resumed. In the case of an Intra-3G_MSC SRNS Relocation (with or without change of radio resources) on 3G_MSC-B, then the messages shall be queued by 3G_MSC-B. 6.2.3.2 With multiple bearers (Optional functionality) If 3G_MSC-A supports the optional supplementary service Multicall (See 3GPP TS 23.135), 3G_MSC-A shall have the following functionality additionally to the description in section 6.2.3.1. Upon receipt of the IU-RELOCATION-REQUIRED from RNS-A, 3G_MSC-A generates an IU-RELOCATIONREQUEST message, which may include multiple bearers, to RNS-B. When an IU-RELOCATION-REQUEST-ACK is received from RNS-B, 3G_MSC-A sends IU-RELOCATIONCOMMAND, which indicates the bearers failed to set up in RNS-B as bearers to be released, to RNS-A. After 3G_MSC-A receives IU-RELOCATION-COMPLETE message from RNS-B, 3G_MSC-A shall release calls via RNS-B, which has been carried by the bearers failed to set up in RNS-B, and then sends IU-RELEASE-COMMAND to RNS-A. 7 General description of the procedures for inter - MSC handovers The following subclauses describe two options for the Basic and Subsequent Handover procedures. The first, as described in subclauses 7.1 and 7.3 respectively, provides for a circuit connection between MSC-A and MSC-B. The second, as described in subclauses 7.2 and 7.4 respectively, provides for a Basic and Subsequent Handover without the provision of a circuit connection between MSC-A and MSC-B. In all the above mentioned subclauses, the following principles apply: a) during the handover resource allocation, except for the messages explicitly indicated in b and c below, only the handover related messages that are part of the applicable BSSAP subset - as defined in 3GPP TS 09.08 [7] - shall be transferred on the E-interface; b) the trace related messages that are part of the applicable BSSAP subset - as defined in 3GPP TS 09.08 [7] - can be sent by the MSC-A on the E-interface after successful handover resource allocation. In the subclauses 7.1 and 7.2, it is however allowed at basic handover initiation on the E-Interface to transfer one trace related message that is part of the applicable BSSAP subset - as defined in 3GPP TS 09.08 [7] - together with the applicable handover related message. The applicable handover related message shall always appear as the first message; c) during the handover resource allocation for subsequent inter-MSC handover according to subclauses 7.3 and 7.4, it is allowed to transfer either DTAP or RANAP Direct Transfer messages on the E-Interface between MSC-A and MSC-B. RANAP Direct Transfer messages shall be used for this purpose if and only if the basic handover procedure was an inter MSC SRNS relocation; d) during the handover execution, ie while the MS is not in communication with the network, the MSC-A shall queue all outgoing BSSAP or RANAP messages until the communication with the MS is resumed; e) during the execution of a basic inter-MSC handover to MSC-B or a subsequent inter-MSC handover to a third MSC-B’, only the handover related messages and the A-Clear-Request message that are part of the applicable BSSAP subset - as defined in 3GPP TS 09.08 [7] – may be sent by the target MSC on the E-interface; 3GPP
  • 30. Release 1999 30 3GPP TS 23.009 V3.14.0 (2003-06) f) during a subsequent inter-MSC handover back to MSC-A or to a third MSC-B’, MSC-B may initiate either an Iu-Release-Request procedure or an A-Clear-Request procedure on the E-interface. An Iu-Release-Request procedure shall be initiated only if the basic handover procedure was an inter-MSC SRNS relocation; g) finally, during supervision, ie while the MS is not in the area of MSC-A after a successful Inter-MSC handover, the subset of BSSAP procedures and their related messages - as defined in 3GPP TS 09.08 [7] - shall apply on the E-Interface. As the only exception to this rule, in case of a subsequent inter-MSC SRNS relocation back to 3G_MSC-A or to a third 3G_MSC-B’, during the relocation resource allocation, the relocation and trace related messages that are part of the applicable RANAP subset - as defined in 3GPP TS 29.108 [15] - shall be transferred on the E-interface (see subclause 8.3, a and b). If a subsequent inter-MSC handover/relocation back to 3G_MSC-A or to a third 3G_MSC-B’ is cancelled, then the supervision continues, and BSSAP procedures and their related messages shall apply on the E-interface. NOTE: A subsequent inter-MSC SRNS relocation back to 3G_MSC-A or to a third 3G_MSC-B’ can occur, e.g., if after the basic inter-MSC handover to 3G_MSC-B the MS performed a subsequent intra-3G_MSC-B GSM to UMTS inter-system handover; h) during the intra-MSC-B handover execution, if any, the MSC-B shall queue all outgoing BSSAP messages until the communication with the MS is resumed. 7.1 Basic handover procedure requiring a circuit connection between MSC-A and MSC-B The procedure used for successful Inter-MSC Handover is shown in figure 12. Initiation of the handover procedure is described in clause 5. The procedure described in this subclause makes use of messages from the 3GPP TS 08.08 [5] and of the transport mechanism from the Mobile Application Part (MAP) (3GPP TS 29.002 [12]). After an Inter-MSC handover further Intra-MSC handovers may occur on MSC-B, these handovers will follow the procedures specified in the previous clause. MS/BSS-A BSS-B/MS MSC-A MSC-B VLR-B A-HO-REQUIRED MAP-Prep-Handover req. MAP-Allocate-Handover-Number req. A-HO-REQUEST A-HO-REQUEST-ACK MAP-Prep-Handover resp. MAP-Send-Handover-Report req. IAM MAP-Send-Handover-Report resp. (1) A-HO-COMMAND ACM MAP-Process-Access-Sig req. A-CLR-CMD/COM A-HO-DETECT MAP-Send-End-Signal req. A-HO-COMPLETE ANSWER End of call RELEASE MAP-Send-End-Signal resp. NOTE 1: Can be sent at any time after the reception of IAM. Figure 12: Basic Handover Procedure requiring a circuit connection 3GPP
  • 31. Release 1999 31 3GPP TS 23.009 V3.14.0 (2003-06) The handover is initiated as described in subclause 6.1. (This is represented by A-HO-REQUIRED in figure 12. Upon receipt of the A-HO-REQUIRED from BSS-A, MSC-A shall send a MAP-PREPARE-HANDOVER request to MSC-B including a complete A-HO-REQUEST message. NOTE: MSC-A shall not send further MAP-PREPARE-HANDOVER requests while a MAP-PREPAREHANDOVER response is pending or before any timeouts. The MAP-PREPARE-HANDOVER request shall carry in the A-HO-REQUEST all information needed by MSC-B for allocating a radio channel, see 3GPP TS 08.08 [5]. For compatibility reasons, the MAP-PREPARE-HANDOVER request will also identify the cell to which the call is to be handed over. MSC-B will return the MAP-PREPAREHANDOVER response after having retrieved a Handover Number from its associated VLR (exchange of the messages MAP-allocate-handover-number request and MAP-send-handover-report request). The Handover Number shall be used for routing the connection of the call from MSC-A to MSC-B. If a traffic channel is available in MSC-B the MAPPREPARE-HANDOVER response, sent to MSC-A will contain the complete A-HO-REQUEST-ACKNOWLEDGE message received from BSS-B, containing the radio resources definition to be sent by BSS-A to the MS and possible extra BSSMAP information, amended by MSC-B due to the possible interworking between the BSSMAP protocol carried on the E-interface and the BSSMAP protocol used on the A-interface. If the traffic channel allocation is queued by BSS-B, the A-QUEUING-INDICATION may optionaly be sent back to MSC-A. The further traffic channel allocation result (A-HO-REQUEST-ACK or A-HO-FAILURE) will be transferred to MSC-A using the MAPPROCESS-ACCESS-SIGNALLING request. If the traffic channel allocation is not possible, the MAP-PREPAREHANDOVER response containing an A-HO-FAILURE will be sent to MSC-A. MSC-B will do the same if a fault is detected on the identity of the cell where the call has to be handed over. MSC-B simply reports the events related to the dialogue. It is up to MSC-A to decide the action to perform if it receives negative responses or the operation fails due to the expiry of the MAP-PREPARE-HANDOVER timer. If an error related to the TCAP dialogue or to the MAP-PREPARE-HANDOVER request is returned from MSC-B, this will be indicated to MSC-A and MSC-A will terminate the handover attempt. MSC-A may retry the handover attempt using the cell identity list, if provided, or may reject the handover attempt towards BSS-A. The existing connection to the MS shall not be cleared. When the A-HO-REQUEST-ACKNOWLEDGE has been received, MSC-A shall establish a circuit between MSC-A and MSC-B by signalling procedures supported by the network. In figure 12 this is illustrated by the messages IAM (Initial Address Message) and ACM (Address Complete Message) of Signalling System no 7. MSC-B awaits the capturing of the MS (subclause 6.1) on the radio path when the ACM is sent and MSC-A initiates the handover execution when ACM is received (illustrated by the A-HO-COMMAND and described in the subclause 6.1). MSC-B transfers to MSC-A the acknowledgement received from the correct MS (A-HO-DETECT/A-HOCOMPLETE). The A-HO-DETECT, if received, is transferred to MSC-A using the MAP-PROCESS-ACCESSSIGNALLING request. The A-HO-COMPLETE, when received from the correct MS, is included in the MAP-SENDEND-SIGNAL request and sent back to MSC-A. The circuit is through-connected in MSC-A when the A-HO-DETECT or the A-HO-COMPLETE is received from MSC-B. The old radio channel is released when the A-HO-COMPLETE message is received from MSC-B. The sending of the MAP-SEND-END-SIGNAL request starts the MAP supervision timer for the MAP dialogue between MSC-A and MSC-B. When the MAP-SEND-END-SIGNAL request including the A-HO-COMPLETE message is received in MSC-A the resources in BSS-A shall be cleared. In order not to conflict with the PSTN/ISDN signalling system(s) used between MSC-A and MSC-B, MSC-B must generate an answer signal when A-HO-DETECT/COMPLETE is received. MSC-B shall release the Handover Number when the circuit between MSC-A and MSC-B has been established. If the circuit between MSC-A and MSC-B cannot be established (e.g. an unsuccessful backward message is received instead of ACM). MSC-A terminates the inter-MSC handover attempt by sending an appropriate MAP message, for example an ABORT. MSC-A may retry the handover at this point, see subclause 6.1. MSC-A shall retain overall call control until the call is cleared by the fixed subscriber or the MS and there is no further call control functions to be performed (e.g. servicing waiting calls, echo cancellers). When MSC-A clears the call to the MS it also clears the call control functions in MSC-A and sends the MAP-SENDEND-SIGNAL response to release the MAP resources in MSC-B. MSC-A may terminate the procedure at any time by sending an appropriate MAP message to MSC-B. If establishment of the circuit between MSC-A and MSC-B has been initiated, the circuit must also be cleared. 3GPP
  • 32. Release 1999 32 3GPP TS 23.009 V3.14.0 (2003-06) The handover will be aborted by MSC-A if it detects clearing or interruption of the radio path before the call has been established on MSC-B. 7.2 Basic handover procedure not requiring the establishment of a circuit connection between MSC-A and MSC-B The basic handover procedures to be used when no circuit connection is required by MSC-A are similar to those described in subclause 7.1 for circuit switched calls. The main differences to the procedures described in subclause 7.1 relate to the establishment of circuits between the network entities and the Handover Number allocation. In the case of ongoing GSM voice group calls the circuit connections are already established therefore the procedures described in this subclause are also applicable. When applied to ongoing voice group calls the clearing of resources on BSS-A shall not be used if the resources are still be used on the down link. Consequently the A-CLEAR-COMMAND message shall not be sent, but an HANDOVER-SUCCEEDED message shall be sent. In the case of basic handover, MSC-A shall specify to MSC-B that no Handover Number is required in the MAPPREPARE-HANDOVER request (see 3GPP TS 29.002 [12]). As for the basic handover using a circuit connection, the A-HO-REQUEST is transmitted at the same time. Any subsequent Handover Number allocation procedure will not be invoked until the completion of the basic handover procedure (see clause: Subsequent Channel Assignment using a circuit connection). MSC-B shall then perform the radio resources allocation as described in subclause 7.1. The MAP-PREPARE-HANDOVER response shall be returned to MSC-A including either the response of the radio resources allocation request received from BSS-B (A-HO-REQUEST-ACKNOWLEDGE/A-HO-FAILURE with possible extra BSSMAP information. These extra information are amended by MSC-B due to the possible interworking between the BSSMAP protocol carried on the E-interface and the BSSMAP protocol used on the A-interface) or potentially the A-QUEUING-INDICATION . The basic handover procedure will continue as described in subclause 7.1 except that no circuit connection will be established towards MSC-B. The relevant case for the basic handover without circuit connection is shown in figure 13. As can be seen the major differences to the equivalent figure 12 is the omission of any circuit establishment messaging and the omission of handover number allocation signalling. MS/BSS-A BSS-B/MS MSC-A MSC-B VLR-B A-HO-REQUIRED MAP-Prep-Handover req. A-HO-REQUEST A-HO-REQUEST-ACK A-HO-COMMAND MAP-Prep-Handover resp. MAP-Process-Access-Sig req. A-CLR-CMD/COM End of link A-HO-DETECT MAP-Send-End-Signal req. A-HO-COMPLETE MAP-Send-End-Signal resp. Figure 13: Basic Handover Procedure without circuit connection 3GPP
  • 33. Release 1999 7.3 33 3GPP TS 23.009 V3.14.0 (2003-06) Procedure for subsequent handover requiring a circuit connection After the call has been handed over to MSC-B, if the MS leaves the area of MSC-B during the same call, subsequent handover is necessary in order to continue the connection. The following cases apply: i) the MS moves back to the area of MSC-A; ii) the MS moves into the area of a third MSC (MSC-B'). In both cases the call is switched in MSC-A; the circuit between MSC-A and MSC-B shall be released after a successful subsequent handover has been performed. 7.3.1 Description of subsequent handover procedure i): MSC-B to MSC-A The procedure for successful handover from MSC-B back to MSC-A is shown in figure 14. MS/BSS-B BSS-A/MS MSC-A MSC-B VLR-B A-HO-REQUIRED MAP-Prep-Sub-Handover req. A-HO-REQUEST A-HO-REQUEST-ACK MAP-Prep-Sub-Handover resp. A-HO-COMMAND MAP-Send-End-Signal resp. A-CLR-CMD/COM A-HO-DETECT A-HO-COMPLETE Release Figure 14: Subsequent handover procedure i):successful handover from MSC-B to MSC-A using a circuit connection The procedure is as follows. MSC-B sends the MAP-PREPARE-SUBSEQUENT-HANDOVER request to MSC-A indicating the new MSC number(MSC-A number), indicating also the identity of the cell where the call has to be handed over and including a complete A-HO-REQUEST message. (NOTE: MSC-B shall not send further MAP-PREPARE-SUBSEQUENTHANDOVER requests while a handover attempt is pending or before any timeouts). Since MSC-A is the call controlling MSC, this MSC needs no Handover Number for routing purposes; MSC-A can immediately initiate the search for a free radio channel. When a radio channel can be assigned, MSC-A shall return in the MAP-PREPARE-SUBSEQUENT-HANDOVER response the complete A-HO-REQUEST-ACKNOWLEDGE message received from the BSS-B and possible extra BSSMAP information, amended by MSC-A due to the possible interworking between the BSSMAP protocol carried on the E-interface and the BSSMAP protocol used on the A-interface. If the traffic channel allocation is queued by BSS-B, the A-QUEUING-INDICATION may optionaly be sent back to MSC-B. The further traffic channel allocation result (A-HO-REQUEST-ACK or A-HO-FAILURE) will be transferred to MSC-B using the MAP-FORWARD-ACCESSSIGNALLING request.If a radio channel cannot be assigned or if a fault is detected on the target cell identity, or the target cell identity in the A-HO-REQUEST is not consistent with the target MSC number, the MAP-PREPARESUBSEQUENT-HANDOVER response containing an A-HO-FAILURE message shall be given to MSC-B, in addition MSC-B shall maintain the connection with the MS. 3GPP
  • 34. Release 1999 34 3GPP TS 23.009 V3.14.0 (2003-06) If the procedure in MSC-A is successful then MSC-B can request the MS to retune to the new BSS-B on MSC-A. This is illustrated in figure 14 by the A-HO-COMMAND message. The operation is successfully completed when MSC-A receives the A-HO-COMPLETE message. After handover MSC-A shall release the circuit to MSC-B. MSC-A must also terminate the MAP procedure for the basic handover between MSC-A and MSC-B by sending an appropriate MAP message. MSC-B will clear the resources in BSS-A when the MAP-SEND-END-SIGNAL response is received. 7.3.2 Description of the subsequent handover procedure ii): MSC-B to MSC-B' The procedure for successful handover from MSC-B to MSC-B' is shown in figure 15. The procedure consists of two parts: - a subsequent handover from MSC-B back to MSC-A as described in subclause 7.3.1 (the same procedures apply if MSC-A is replaced by 3G_MSC-A); and - a basic handover from MSC-A to MSC-B' as described in subclause 7.1. MSC-B sends the MAP-PREPARE-SUBSEQUENT-HANDOVER request to MSC-A indicating a new MSC number (which is the identity of MSC-B'), indicating also the target cell identity and including a complete A-HO-REQUEST, MSC-A then starts a basic handover procedure towards MSC-B'. When MSC-A receives the ACM from MSC-B', MSC-A informs MSC-B that MSC-B' has successfuly allocated the radio resources on BSS-B' side by sending the MAP-PREPARE-SUBSEQUENT-HANDOVER response containing the complete A-HO-REQUEST-ACKNOWLEDGE received from BSS-B'and possible extra BSSMAP information, amended by MSC-A due to the possible interworking between the BSSMAP protocol carried on the E-interface between MSC-A and MSC-B' and the BSSMAP protocol carried on the E-interface between MSC-A and MSC-B. Now MSC-B can start the procedure on the radio path. For MSC-A the handover is completed when it has received the MAP-SEND-END-SIGNAL REQUEST from MSC-B'containing the A-HO-COMPLETE received from the BSS-B'. The circuit between MSC-A and MSC-B is released. MSC-A also sends the MAP-SEND-END-SIGNAL response to MSC-B in order to terminate the original MAP dialogue between MSC-A and MSC-B. MSC-B releases the radio resources when it receives this message. If the traffic channel allocation is queued by the BSS-B', the A-QUEUING-INDICATION may optionaly be sent back to MSC-B. If no radio channel can be allocated by MSC-B' or no circuit between MSC-A and MSC-B' can be established or a fault is detected on the target cell identity or the target cell identity in the A-HO-REQUEST is not consistent with the target MSC number, MSC-A informs MSC-B by using the A-HO-FAILURE message included in the MAP-PREPARE-SUBSEQUENT-HANDOVER response. MSC-B shall maintain the existing connection with the MS. When the subsequent handover is completed, MSC-B' is considered as MSC-B. Any further inter-MSC handover is handled as described above for a subsequent handover. 3GPP
  • 35. Release 1999 35 3GPP TS 23.009 V3.14.0 (2003-06) MS/BSS MSC-B’ MSC-A MSC-B VLR-B’ VLR-B A-HO-REQUIRED MAP-Prep-Sub-Handover req. MAP-Prepare-Handover req. MAP-Allocate-Handover-Number req. MAP-Prepare-Handover resp. MAP-Send-Handover-Report req. IAM MAP-Send-Handover-Rep. resp. (1) ACM MAP-Prep-Sub-Ho resp. A-HO-COMMAND A-HO-DETECT MAP-Process-Access-Signalling req. A-HO-COMPLETE MAP-Send-End-Signal req. Answer Release MAP-Send-End-Signal resp. A-CLR-CMD/COM (end of call) Release MAP-Send-End-Signal resp. NOTE 1: Can be sent at any time after the reception of IAM. Figure 15: Subsequent handover procedure ii): Successful handover from MSC-B to MSC-B'requiring a circuit connection 7.4 Procedure for subsequent handover not requiring a circuit connection As for the subsequent handover with a circuit connection, the same two cases of subsequent handover apply: i) the MS moves back to the area of MSC-A; ii) the MS moves into the area of a third MSC (MSC-B'). 3GPP
  • 36. Release 1999 7.4.1 36 3GPP TS 23.009 V3.14.0 (2003-06) Description of the subsequent handover procedure without circuit connection i): MSC-B to MSC-A The procedure for successful handover from MSC-B back to MSC-A without circuit connection is shown in figure 16. The only difference with the figure 14, is that no circuit release is needed between MSC-A and MSC-B. MS/BSS-B BSS-A/MS MSC-A MSC-B VLR-B A-HO-REQUIRED MAP-Prep-Sub-Handover req. A-HO-REQUEST A-HO-REQUEST-ACK MAP-Prep-Sub-Handover resp. A-HO-COMMAND MAP-Send-End-Signal resp. A-CLR-CMD/COM A-HO-DETECT A-HO-COMPLETE Figure 16: Subsequent handover procedure i): Successful handover from MSC-B to MSC-A not requiring a circuit connection 7.4.2 Description of the subsequent handover procedure without circuit connection ii): MSC-B to MSC-B' The procedure for successful handover from MSC-B to MSC-B' is shown in figure 17. The procedure consists of two parts: - a subsequent handover from MSC-B back to MSC-A as described in subclause 7.4.1(the same procedures apply if MSC-A is replaced by 3G_MSC-A); and - a basic handover from MSC-A to MSC-B' as described in subclause 7.2. The only difference to the equivalent figure 15 is the omission of the circuit and handover number allocation signallings. 3GPP
  • 37. Release 1999 37 3GPP TS 23.009 V3.14.0 (2003-06) MS/BSS MSC-B’ MSC-A MSC-B VLR-B’ VLR-B A-HO-REQUIRED MAP-Prep-Sub-Handover req. MAP-Prepare-Handover req. MAP-Prepare-Handover resp. MAP-Prep-Sub-Ho resp. A-HO-COMMAND A-HO-DETECT MAP-Process-Access-Signalling req. A-HO-COMPLETE MAP-Send-End-Signal req. MAP-Send-End-Signal resp. A-CLR-CMD/COM (end of link) MAP-Send-End-Signal resp. Figure 17: Subsequent handover procedure ii): Successful handover from MSC-B to MSC-B' without circuit connection 8 General Description of the procedures for inter 3G_MSC handovers 8.1 Handover UMTS to GSM The following subclauses describe two options for the Basic and Subsequent UMTS to GSM Handover procedures. The first, as described in subclauses 8.1.1 and 8.1.3 respectively, provides for a circuit connection between 3G_MSC-A and 3G_MSC-B. The second, as described in subclauses 8.1.2 and 8.1.4 respectively, provides for a Basic and Subsequent Handover without the provision of a circuit connection between 3G_MSC-A and 3G_MSC-B. 3G_MSC can also be a pure GSM MSC. In all the above mentioned subclauses, the following principles apply: a) during the handover resource allocation, except for the messages explicitly indicated in b and c below, only the handover related messages that are part of the applicable BSSAP subset - as defined in 3GPP TS 09.08 [7] - shall be transferred on the E-interface; b) the trace related messages that are part of the applicable BSSAP subset - as defined in 3GPP TS 09.08- can be sent by the 3G_MSC-A on the E-interface after successful handover resource allocation. In the subclauses 8.1.1 and 8.1.2, it is however allowed at basic handover initiation on the E-Interface to transfer one trace related message that is part of the applicable BSSAP subset - as defined in 3GPP TS 09.08 [7] - together with the applicable handover related message. The applicable handover related message shall always appear as the first message; 3GPP
  • 38. Release 1999 38 3GPP TS 23.009 V3.14.0 (2003-06) c) during the handover resource allocation for subsequent inter-MSC inter-system handover according to subclauses 8.1.3 and 8.1.4, it is allowed to transfer either DTAP or RANAP Direct Transfer messages on the EInterface between 3G_MSC-A and 3G_MSC-B. RANAP Direct Transfer messages shall be used for this purpose if and only if the basic handover procedure was an inter MSC SRNS relocation; d) during the handover execution, i.e. while the UE/MS is not in communication with the network, the 3G_MSC-A shall queue all outgoing BSSAP or RANAP messages until the communication with the UE/MS is resumed; e) during the execution of a basic inter-system inter-MSC handover to MSC-B or a subsequent inter-system interMSC handover to a third MSC-B’, only the handover related messages and the A-Clear-Request message that are part of the applicable BSSAP subset - as defined in 3GPP TS 09.08 [7] – may be sent by the target MSC on the E-interface; f) during a subsequent inter-system inter-MSC handover back to 3G_MSC-A or to a third MSC-B’, 3G_MSC-B may initiate either an Iu-Release-Request procedure or an A-Clear-Request procedure on the E-interface. An IuRelease-Request procedure shall be initiated only if the basic handover procedure was an inter-MSC SRNS relocation; g) finally, during supervision, i.e. while the UE/MS is not in the area of 3G_MSC-A after a successful Inter3G_MSC handover, the subset of BSSAP procedures and their related messages - as defined in 3GPP TS 09.08 [7] - shall apply on the E-Interface. As the only exception to this rule, in case of a subsequent inter-MSC SRNS relocation back to 3G_MSC-A or to a third 3G_MSC-B’, during the relocation resource allocation, the relocation and trace related messages that are part of the applicable RANAP subset - as defined in 3GPP TS 29.108 [15] shall be transferred on the E-interface (see subclause 8.3, a and b). If a subsequent inter-MSC handover/relocation back to 3G_MSC-A or to a third 3G_MSC-B’ is cancelled, then the supervision continues, and BSSAP procedures and their related messages shall apply on the E-interface. NOTE: A subsequent inter-MSC SRNS relocation back to 3G_MSC-A or to a third 3G_MSC-B’ can occur, e.g., if after the basic inter-MSC handover to 3G_MSC-B the MS performed a subsequent intra-3G_MSC-B GSM to UMTS inter-system handover; h) during the intra-3G_MSC -B handover execution, if any, the 3G_MSC -B shall queue all outgoing BSSAP or RANAP messages until the communication with the UE/MS is resumed. 8.1.1 Basic Handover procedure requiring a circuit connection between 3G_MSC -A and MSC-B The procedure used for successful Inter-3G_MSC UMTS to GSM Handover is shown in figure 18. Initiation of the UMTS to GSM handover procedure is described in clause 5. The procedure described in this subclause makes use of messages from the 3GPP TS 08.08 and of the transport mechanism from the Mobile Application Part (MAP) (3GPP TS 29.002 [12]). After an Inter-3G_MSC relocation/handover, Intra-3G_MSC UMTS to GSM handover may occur on 3G_MSC -B, this handover will follow the procedures specified in a previous subclause. 3GPP
  • 39. Release 1999 39 UE/MS/RNS-A 3GPP TS 23.009 V3.14.0 (2003-06) BSS-B/MS/UE 3G MSC-A Iu-RELOCATIONREQUIRED MSC-B MAP-Prep-Handover req. VLR-B MAP-Allocate-Handover-Number req. A-HO-REQUEST A-HO-REQUEST-ACK MAP-Prep-Handover resp. MAP-Send-Handover-Report req. IAM MAP-Send-Handover-Report resp. (1) Iu-RELOCATIONCOMMAND ACM MAP-Process-Access-Sig req. Iu-RELEASECMD/COM A-HO-DETECT MAP-Send-End-Signal req. A-HO-COMPLETE ANSWER End of call RELEASE MAP-Send-End-Signal resp. NOTE 1: Can be sent at any time after the reception of IAM. Figure 18: Basic UMTS to GSM Handover Procedure requiring a circuit connection 8.1.1.1 With one circuit connection The UMTS to GSM handover is initiated as described in subclause 6.2.1. (This is represented by Iu-RELOCATIONREQUIRED in figure 18). Upon receipt of the Iu-RELOCATION-REQUIRED from RNS-A, 3G_MSC-A shall send a MAP-PREPARE-HANDOVER request to MSC-B including a complete A-HO-REQUEST message. NOTE: 3G_MSC-A shall not send further MAP-PREPARE-HANDOVER requests while a MAP-PREPAREHANDOVER response is pending or before any timeouts. The MAP-PREPARE-HANDOVER request shall carry in the A-HO-REQUEST all information needed by MSC-B for allocating a radio channel, see 3GPP TS 08.08. For compatibility reasons, the MAP-PREPARE-HANDOVER request will also identify the cell to which the call is to be handed over. MSC-B will return the MAP-PREPARE-HANDOVER response after having retrieved a Handover Number from its associated VLR (exchange of the messages MAP-allocatehandover-number request and MAP-send-handover-report request). The Handover Number shall be used for routing the connection of the call from 3G_MSC-A to MSC-B. If a traffic channel is available in MSC-B the MAP-PREPAREHANDOVER response, sent to 3G_MSC-A will contain the complete A-HO-REQUEST-ACKNOWLEDGE message received from BSS-B, containing the radio resources definition to be sent by RNS-A to the UE/MS and possible extra BSSMAP information, amended by MSC-B due to the possible interworking between the BSSMAP protocol carried on the E-interface and the BSSMAP protocol used on the A-interface. If the traffic channel allocation is queued by BSS-B, the A-QUEUING-INDICATION may optionally be sent back to 3G_MSC-A. The further traffic channel allocation result (A-HO-REQUEST-ACK or A-HO-FAILURE) will be transferred to 3G_MSC-A using the MAP-PROCESSACCESS-SIGNALLING request. If the traffic channel allocation is not possible, the MAP-PREPARE-HANDOVER response containing an A-HO-FAILURE will be sent to 3G_MSC-A. MSC-B will do the same if a fault is detected on the identity of the cell where the call has to be handed over. MSC-B simply reports the events related to the dialogue. It is up to 3G_MSC-A to decide the action to perform if it receives negative responses or the operation fails due to the expiry of the MAP-PREPARE-HANDOVER timer. If an error related to the TCAP dialogue or to the MAP-PREPARE-HANDOVER request is returned from MSC-B, this will be indicated to 3G_MSC-A and 3G_MSC-A will terminate the handover attempt. 3G_MSC-A rejects the handover attempt towards RNS-A. The existing connection to the UE/MS shall not be cleared. 3GPP
  • 40. Release 1999 40 3GPP TS 23.009 V3.14.0 (2003-06) When the A-HO-REQUEST-ACKNOWLEDGE has been received, 3G_MSC-A shall establish a circuit between 3G_MSC-A and MSC-B by signalling procedures supported by the network. In figure 18 this is illustrated by the messages IAM (Initial Address Message) and ACM (Address Complete Message) of Signalling System no 7. MSC-B awaits the capturing of the UE/MS (subclause 6.2.1) on the radio path when the ACM is sent and 3G_MSC-A initiates the UMTS to GSM handover execution when ACM is received (illustrated by the Iu-RELOCATION-COMMAND and described in the subclause 6.2.1). 3G_MSC-A removes the transcoder from the path to the other party. As handover to GSM means that a transcoder is inserted in the BSS-B then G.711 [16] is assumed on the E-interface. MSC-B transfers to 3G_MSC-A the acknowledgement received from the correct UE/MS (A-HO-DETECT/A-HOCOMPLETE). The A-HO-DETECT, if received, is transferred to 3G_MSC-A using the MAP-PROCESS-ACCESSSIGNALLING request. The A-HO-COMPLETE, when received from the correct UE/MS, is included in the MAPSEND-END-SIGNAL request and sent back to 3G_MSC-A. The circuit is through connected in 3G_MSC-A when the A-HO-DETECT or the A-HO-COMPLETE is received from MSC-B. The old radio channel is released when the AHO-COMPLETE message is received from MSC-B. The sending of the MAP-SEND-END-SIGNAL request starts the MAP supervision timer for the MAP dialogue between 3G_MSC-A and MSC-B. When the MAP-SEND-ENDSIGNAL request including the A-HO-COMPLETE message is received in 3G_MSC-A, the resources in RNS-A shall be cleared. In order not to conflict with the PSTN/ISDN signalling system(s) used between 3G_MSC-A and MSC-B, MSC-B must generate an answer signal when A-HO-DETECT/COMPLETE is received. MSC-B shall release the Handover Number when the circuit between 3G_MSC-A and MSC-B has been established. If the circuit between 3G_MSC-A and MSC-B cannot be established, (e.g. an unsuccessful backward message is received instead of ACM), 3G_MSC-A terminates the inter-3G_MSC UMTS to GSM handover attempt by sending an appropriate MAP message, for example an ABORT. 3G_MSC-A shall retain overall call control until the call is cleared by the fixed subscriber or the UE/MS and there is no further call control functions to be performed (e.g. servicing waiting calls, echo cancellers). When 3G_MSC-A clears the call to the UE/MS it also clears the call control functions in 3G_MSC-A and sends the MAP-SEND-END-SIGNAL response to release the MAP resources in MSC-B. 3G_MSC-A may terminate the procedure at any time by sending an appropriate MAP message to MSC-B. If establishment of the circuit between 3G_MSC-A and MSC-B has been initiated, the circuit must also be cleared. The UMTS to GSM handover will be aborted by 3G_MSC-A if it detects clearing or interruption of the radio path before the call has been established on MSC-B. 8.1.1.2 With multiple circuit connections (Optional functionality) If 3G_MSC-A supports the optional supplementary service Multicall (See 3GPP TS 23.135), 3G_MSC-A shall have the following functionality additionally to the description in section 8.1.1.1. Upon receipt of the IU-RELOCATION-REQUIRED from RNS-A 3G_MSC-A shall select one bearer to be handed over if the UE is engaged with multiple bearers. After that, the 3G_MSC-A generates an A-HO-REQUEST message for the selected bearer and sends it to MSC-B over MAP-PREPARE-HANDOVER request. When MAP-PREPARE-HANDOVER response including an A-HO-REQUEST-ACK is received from MSC-B, 3G_MSC-A sends IU-RELOCATION-COMMAND, which indicates the bearers not to be handed over as bearers to be released, to RNS-A. After 3G_MSC-A receives MAP-SEND-END-SIGNAL request from MSC-B, 3G_MSC-A shall release calls via MSCB, which has been carried by the bearers not to be handed over, and then 3G_MSC-A sends IU-RELEASECOMMAND to RNS-A. 8.1.2 Basic UMTS to GSM Handover procedure not requiring the establishment of a circuit connection between 3G_MSC-A and MSC-B The basic UMTS to GSM handover procedures to be used when no circuit connection is required by 3G_MSC-A are similar to those described in subclause 8.1.1 for circuit switched calls. The main differences to the procedures described 3GPP
  • 41. Release 1999 41 3GPP TS 23.009 V3.14.0 (2003-06) in subclause 8.1.1 relate to the establishment of circuits between the network entities and the Handover Number allocation. In the case of basic UMTS to GSM handover, 3G_MSC-A shall specify to MSC-B that no Handover Number is required in the MAP-PREPARE-HANDOVER request (see 3GPP TS 29.002 [12]). As for the basic UMTS to GSM handover using a circuit connection, the A-HO-REQUEST is transmitted at the same time. Any subsequent Handover Number allocation procedure will not be invoked until the completion of the basic UMTS to GSM handover procedure (see clause: Subsequent Channel Assignment using a circuit connection). MSC-B shall then perform the radio resources allocation as described in subclause 8.1.1. The MAP-PREPARE-HANDOVER response shall be returned to 3G_MSC-A including either the response of the radio resources allocation request received from BSS-B (A-HOREQUEST-ACKNOWLEDGE/A-HO-FAILURE with possible extra BSSMAP information. These extra information are amended by MSC-B due to the possible interworking between the BSSMAP protocol carried on the E-interface and the BSSMAP protocol used on the A-interface) or potentially the A-QUEUING-INDICATION. The basic UMTS to GSM handover procedure will continue as described in subclause 8.1.1 except that no circuit connection will be established towards MSC-B. The relevant case for the basic UMTS to GSM handover without circuit connection is shown in figure 19. As can be seen the major differences to the equivalent figure 18 is the omission of any circuit establishment messaging and the omission of handover number allocation signalling. UE/MS/RNS-A BSS-B/UE/MS 3G MSC-A Iu-RELOCATIONREQUIRED MSC-B VLR-B MAP-Prep-Handover req. A-HO-REQUEST A-HO-REQUEST-ACK Iu-RELOCATIONCOMMAND MAP-Prep-Handover resp. MAP-Process-Access-Sig req. Iu-RELEASECMD/COM End of link A-HO-DETECT MAP-Send-End-Signal req. A-HO-COMPLETE MAP-Send-End-Signal resp. Figure 19: Basic UMTS to GSM Handover Procedure without circuit connection 8.1.3 Procedure for subsequent UMTS to GSM handover requiring a circuit connection After the call has been handed over to 3G_MSC-B, if the UE/MS leaves the area of 3G_MSC-B during the same call and enters a GSM area, subsequent UMTS to GSM handover is necessary in order to continue the connection. The following cases apply: i) the UE/MS moves back to the area of MSC-A; ii) the UE/MS moves into the area of a third MSC (MSC-B'). In both cases the call is switched in 3G_MSC-A; the circuit between 3G_MSC-A and MSC-B shall be released after a successful subsequent handover has been performed the same procedures apply if 3G_MSC-A is replaced by MSC-A. 3GPP
  • 42. Release 1999 8.1.3.1 42 3GPP TS 23.009 V3.14.0 (2003-06) Description of subsequent UMTS to GSM handover procedure i): 3G_MSC-B to MSC-A The procedure for successful UMTS to GSM handover from MSC-B back to 3G_MSC-A is shown in figure 20. UE/MS/BSS-B RNS-A/UE/MS 3G MSC-B MSC-A VLR-B Iu-RELOCATIONREQUIRED MAP-Prep-Sub-Handover req. A-HO-REQUEST A-HO-REQUEST-ACK MAP-Prep-Sub-Handover resp. Iu-RELOCATIONCOMMAND MAP-Send-End-Signal resp. Iu-RELEASECMD/COM A-HO-DETECT A-HO-COMPLETE Release Figure 20: Subsequent UMTS to GSM handover procedure i): successful UMTS to GSM handover from 3G_MSC-B to MSC-A using a circuit connection 8.1.3.1.1 With one circuit connection The procedure is as follows. 3G_MSC-B sends the MAP-PREPARE-SUBSEQUENT-HANDOVER request to MSC-A indicating the new MSC number (MSC-A number), indicating also the identity of the cell where the call has to be handed over and including a complete A-HO-REQUEST message. (NOTE: 3G_MSC-B shall not send further MAP-PREPARE-SUBSEQUENTHANDOVER requests while a handover attempt is pending or before any timeouts). Since MSC-A is the call controlling MSC, this MSC needs no Handover Number for routing purposes; MSC-A can immediately initiate the search for a free radio channel. When a radio channel can be assigned, MSC-A shall return in the MAP-PREPARE-SUBSEQUENT-HANDOVER response the complete A-HO-REQUEST-ACKNOWLEDGE message received from the BSS-B and possible extra BSSMAP information, amended by MSC-A due to the possible interworking between the BSSMAP protocol carried on the E-interface and the BSSMAP protocol used on the A-interface. If the traffic channel allocation is queued by BSS-B, the A-QUEUING-INDICATION may optionally be sent back to 3G_MSC-B. The further traffic channel allocation result (A-HO-REQUEST-ACK or A-HO-FAILURE) will be transferred to 3G_MSC-B using the MAP-FORWARDACCESS-SIGNALLING request. If a radio channel cannot be assigned or if a fault is detected on the target cell identity, or the target cell identity in the A-HO-REQUEST is not consistent with the target MSC number, the MAP-PREPARESUBSEQUENT-HANDOVER response containing an A-HO-FAILURE message shall be given to 3G_MSC-B, in addition 3G_MSC-B shall maintain the connection with the UE/MS. If the procedure in MSC-A is successful then 3G_MSC-B can request the UE/MS to retune to the new BSS-B on MSC-A. This is illustrated in figure 20 by the Iu-RELOCATION-COMMAND message. The operation is successfully completed when MSC-A receives the A-HO-COMPLETE message. After UMTS to GSM handover MSC-A shall release the circuit to 3G_MSC-B. MSC-A must also terminate the MAP procedure for the basic UMTS to GSM handover between MSC-A and 3G_MSC-B by sending an appropriate MAP message. 3G_MSC-B will clear the resources in RNS-A when the MAP-SEND-END-SIGNAL response is received. 8.1.3.1.2 With multiple circuit connections (Optional functionality) If 3G_MSC-B supports the optional supplementary service Multicall (See 3GPP TS 23.135), 3G_MSC-B shall have the following functionality additionally to the description in section 8.1.3.1.1. 3GPP
  • 43. Release 1999 43 3GPP TS 23.009 V3.14.0 (2003-06) Upon receipt of the IU-RELOCATION-REQUIRED from RNS-A which indicates the target is BSS, 3G_MSC-B shall select one bearer to be handed over if the UE is engaged with multiple bearers. After that, the 3G_MSC-B generates an A-HO-REQUEST message for the selected bearer and sends it to 3G_MSC-A over MAP-PREPARE-SUBSEQUENTHANDOVER request with indication of RAB ID of the selected bearer. When MAP-PREPARE-SUBSEQUENT-HANDOVER response including an A-HO-REQUEST-ACK is received from the 3G_MSC-A, 3G_MSC-B sends IU-RELOCATION-COMMAND, which indicates the bearers not to be handed over as bearers to be released, to RNS-A. After 3G_MSC-A receives A-HO-COMPLETE message from BSS-B, 3G_MSC-A shall release calls via BSS-B, which has been carried by the bearers not to be handed over, and then 3G_MSC-A sends MAP-SEND-END-SIGNAL response to 3G_MSC-B. 8.1.3.2 Description of subsequent UMTS to GSM handover procedure ii): 3G_MSC-B to MSC-B' The procedure for successful UMTS to GSM handover from 3G_MSC-B to MSC-B' is shown in figure 21. The procedure consists of two parts: - a subsequent UMTS to GSM handover from 3G_MSC-B back to 3G_MSC-A as described in subclause 8.1.3.1 (the same procedures apply if 3G_MSC-A is replaced by MSC-A); and - a basic handover from 3G_MSC-A to MSC-B' as described in subclause 7.1. 8.1.3.2.1 With one circuit connection 3G_MSC-B sends the MAP-PREPARE-SUBSEQUENT-HANDOVER request to 3G_MSC-A indicating a new MSC number (which is the identity of MSC-B'), indicating also the target cell identity and including a complete A-HO-REQUEST, 3G_MSC-A then starts a basic handover procedure towards MSC-B'. When 3G_MSC-A receives the ACM from MSC-B', 3G_MSC-A informs 3G_MSC-B that MSC-B' has successfully allocated the radio resources on BSS-B' side by sending the MAP-PREPARE-SUBSEQUENT-HANDOVER response containing the complete A-HO-REQUEST-ACKNOWLEDGE received from BSS-B' and possible extra BSSMAP information, amended by 3G_MSC-A due to the possible interworking between the BSSMAP protocol carried on the E-interface between 3G_MSC-A and MSC-B' and the BSSMAP protocol carried on the E-interface between 3G_MSC-A and 3G_MSC-B. Now 3G_MSC-B can start the procedure on the radio path. For 3G_MSC-A the UMTS to GSM handover is completed when it has received the MAP-SEND-END-SIGNAL REQUEST from MSC-B' containing the A-HO-COMPLETE received from the BSS-B'. The circuit between 3G_MSC-A and 3G_MSC-B is released. 3G_MSC-A also sends the MAP-SEND-END-SIGNAL response to 3G_MSC-B in order to terminate the original MAP dialogue between 3G_MSC-A and 3G_MSC-B. 3G_MSC-B releases the radio resources when it receives this message. If the traffic channel allocation is queued by the BSS-B', the A-QUEUING-INDICATION may optionally be sent back to 3G_MSC-B. If no radio channel can be allocated by MSC-B' or no circuit between 3G_MSC-A and MSC-B' can be established or a fault is detected on the target cell identity or the target cell identity in the A-HO-REQUEST is not consistent with the target MSC number, 3G_MSC-A informs 3G_MSC-B by using the A-HO-FAILURE message included in the MAP-PREPARE-SUBSEQUENT-HANDOVER response. 3G_MSC-B shall maintain the existing connection with the UE/MS. When the subsequent UMTS to GSM handover is completed, MSC-B' is considered as MSC-B. Any further inter-MSC handover is handled as described earlier for a subsequent handover. 8.1.3.2.2 With multiple circuit connections (Optional functionality) If 3G_MSC-B supports the optional supplementary service Multicall (See 3GPP TS 23.135), 3G_MSC-B shall have the following functionality additionally to the description in section 8.1.3.2.1. Upon receipt of the IU-RELOCATION-REQUIRED from RNS-B 3G_MSC-B shall select one bearer to be handed over if the UE is engaged with multiple bearers. After that, the 3G_MSC-B generates an A-HO-REQUEST message for the selected bearer and sends it to 3G_MSC-A over MAP-PREPARE-SUBSEQUENT-HANDOVER request with indication of RAB ID of the selected bearer. 3GPP
  • 44. Release 1999 44 3GPP TS 23.009 V3.14.0 (2003-06) Upon receipt of the MAP-PREPARE-SUBSEQUENT-HANDOVER request from 3G_MSC-B, 3G_MSC-A starts a basic handover procedure towards MSC-B'. When 3G_MSC-A receives the ACM from MSC-B', 3G_MSC-A informs 3G_MSC-B that MSC-B' has successfully allocated the radio resources on BSS-B' side by sending the MAP-PREPARE-SUBSEQUENT-HANDOVER response containing the complete A-HO-REQUEST-ACK received from BSS-B' and possible extra BSSAP information, amended by 3G_MSC-A due to the possible interworking between the BSSMAP protocol carried on the E-interface between 3G_MSC-A and MSC-B' and the BSSMAP protocol carried on the E-interface between 3G_MSC-A and 3G_MSC-B. When MAP-PREPARE-SUBSEQUENT-HANDOVER response including an A-HO-REQUEST-ACK is received from 3G_MSC-A, 3G_MSC-B sends IU-RELOCATION-COMMAND, which indicates the bearers not to be handed over as bearers to be released, to RNS-A. After 3G_MSC-A receives MAP-SEND-END-SIGNAL request from MSC-B', 3G_MSC-A shall release calls via MSC-B', which has been carried by the bearers not to be handed over, and then 3G_MSC-A sends MAP-SEND-ENDSIGNAL response to 3G_MSC-B. UE/MS/BSS/RNS MSC-B’ 3G_MSC-A 3G_MSC-B VLR-B’ VLR-B Iu-RELOCATIONREQUIRED MAP-Prep-Sub-Handover req. MAP-Prepare-Handover req. MAP-Allocate-Handover-Number req. MAP-Prepare-Handover resp. MAP-Send-Handover-Report req. IAM MAP-Send-Handover-Rep. resp. (1) ACM MAP-Prep-Sub-Ho resp. Iu-RELOCATION-CMD A-HO-DETECT MAP-Process-Access-Signalling req. A-HO-COMPLETE MAP-Send-End-Signal req. Answer Release MAP-Send-End-Signal resp. Iu-RELEASE-CMD/COM (end of call) Release MAP-Send-End-Signal resp. NOTE 1: Can be sent at any time after the reception of IAM. Figure 21: Subsequent handover procedure ii): Successful UMTS to GSM handover from 3G_MSC-B to MSC-B' requiring a circuit connection 3GPP
  • 45. Release 1999 8.1.4 45 3GPP TS 23.009 V3.14.0 (2003-06) Procedure for subsequent UMTS to GSM handover not requiring a circuit connection As for the subsequent UMTS to GSM handover with a circuit connection, the same two cases of subsequent handover apply: i) the UE/MS moves back to the area of MSC-A; ii) the UE/MS moves into the area of a third MSC (MSC-B'). 8.1.4.1 Description of subsequent UMTS to GSM handover procedure i): 3G_MSC-B to MSC-A The procedure for successful UMTS to GSM handover from 3G_MSC-B back to MSC-A without circuit connection is shown in figure 22. The only difference with the figure 20, is that no circuit release is needed between MSC-A and 3G_MSC-B. UE/MS/BSS-B RNS-A/UE/MS MSC-A 3G MSC-B VLR-B Iu-RELOCATIONREQUIRED MAP-Prep-Sub-Handover req. A-HO-REQUEST A-HO-REQUEST-ACK MAP-Prep-Sub-Handover resp. Iu-RELOCATIONCOMMAND MAP-Send-End-Signal resp. Iu-RELEASECMD/COM A-HO-DETECT A-HO-COMPLETE Figure 22: Subsequent UMTS to GSM handover procedure i): Successful UMTS to GSM handover from 3G_MSC-B to MSC-A not requiring a circuit connection 8.1.4.2 Description of the subsequent UMTS to GSM handover procedure without circuit connection ii): 3G_MSC-B to MSC-B' The procedure for successful UMTS to GSM handover from 3G_MSC-B to MSC-B' is shown in figure 23. The procedure consists of two parts: - a subsequent UMTS to GSM handover from 3G_MSC-B back to 3G_MSC-A as described in subclause 8.1.4.1 (the same procedures apply if 3G_MSC-A is replaced by MSC-A); and - a basic handover from 3G_MSC-A to MSC-B' as described in subclause 7.2. The only difference to the equivalent figure 21 is the omission of the circuit and handover number allocation signallings. 3GPP
  • 46. Release 1999 46 3GPP TS 23.009 V3.14.0 (2003-06) UE/MS/BSS/RNS MSC-B’ 3G_MSC-A 3G_MSC-B VLR-B’ VLR-B Iu-RELOCATION-REQUIRED MAP-Prep-Sub-Handover req. MAP-Prepare-Handover req. MAP-Prepare-Handover resp. MAP-Prep-Sub-Ho resp. Iu-RELOCATION-CMD A-HO-DETECT MAP-Process-Access-Signalling req. A-HO-COMPLETE MAP-Send-End-Signal req. MAP-Send-End-Signal resp. Iu-RELEASE-CMD/COM (end of link) MAP-Send-End-Signal resp. Figure 23: Subsequent UMTS to GSM handover procedure ii): Successful UMTS to GSM handover from 3G_MSC-B to MSC-B' without circuit connection 8.2 Handover GSM to UMTS The following subclauses describe two options for the Basic and Subsequent GSM to UMTS Handover procedures. The first, as described in subclauses 8.2.1 and 8.2.3 respectively, provides for a circuit connection between (3G_)MSC-A and (3G_)MSC-B. The second, as described in subclauses 8.2.2 and 8.2.4 respectively, provides for a Basic and Subsequent Handover without the provision of a circuit connection between (3G_)MSC-A and (3G_)MSC-B. In all the above mentioned subclauses, the following principles apply: a) during the handover resource allocation, except for the messages explicitly indicated in b and c below, only the handover related messages that are part of the applicable BSSAP subset - as defined in 3GPP TS 09.08 [7] - shall be transferred on the E-interface; b) the trace related messages that are part of the applicable BSSAP subset - as defined in 3GPP TS 09.08 [7] - can be sent by the MSC-A on the E-interface after successful handover resource allocation. In the subclauses 8.2.1 and 8.2.2, it is however allowed at basic handover initiation on the E-Interface to transfer one trace related message that is part of the applicable BSSAP subset - as defined in 3GPP TS 09.08 [7] - together with the applicable handover related message. The applicable handover related message shall always appear as the first message; c) during the handover resource allocation for subsequent inter-MSC inter-system handover according to subclauses 8.2.3 and 8.2.4, it is allowed to transfer either DTAP or RANAP Direct Transfer messages on the EInterface between MSC-A and 3G_MSC-B. RANAP Direct Transfer messages shall be used for this purpose if and only if the basic handover procedure was an inter MSC SRNS relocation; d) If 3G_MSC-B or 3G-MSC-B’ supports location reporting at change of Service Area, 3G_MSC-B or 3G_MSCB' shall always initiate the Location Reporting Control procedure at change of Service Area towards the target 3GPP
  • 47. Release 1999 47 3GPP TS 23.009 V3.14.0 (2003-06) RNS since no request for Location Reporting can be received from MSC-A. In that case, the Location Reporting Control procedure shall be initiated by 3G_MSC-B or 3G-MSC-B’ after the Relocation Resource Allocation procedure has been executed successfully. The change of Service Area shall be reported to MSC-A within an AHANDOVER-PERFORMED message; e) during the handover execution, i.e. while the UE/MS is not in communication with the network, the MSC-A shall queue all outgoing BSSAP or RANAP messages until the communication with the UE/MS is resumed; f) during the execution of a basic inter-system inter-MSC handover to 3G_MSC-B or a subsequent inter-system inter-MSC handover to a third 3G-MSC-B’, only the handover related messages and the A-Clear-Request message that are part of the applicable BSSAP subset - as defined in 3GPP TS 09.08 [7] – may be sent by the target MSC on the E-interface; g) during a subsequent inter-system inter-MSC handover back to 3G_MSC-A or to a third 3G_MSC-B’, 3G_MSCB may initiate either an Iu-Release-Request procedure or an A-Clear-Request procedure on the E-interface. An Iu-Release-Request procedure shall be initiated only if the basic handover procedure was an inter-MSC SRNS relocation; h) finally, during supervision, i.e. while the UE/MS is not in the area of MSC-A after a successful Inter-3G_MSC GSM to UMTS handover, the subset of BSSAP procedures and their related messages - as defined in 3GPP TS 09.08 [7] - shall apply on the E-Interface. As the only exception to this rule, in case of a subsequent inter-MSC SRNS relocation back to 3G_MSC-A or to a third 3G_MSC-B’, during the relocation resource allocation, the relocation and trace related messages that are part of the applicable RANAP subset - as defined in 3GPP TS 29.108 [15] - shall be transferred on the E-interface (see subclause 8.3, a and b). If a subsequent inter-MSC handover/relocation back to 3G_MSC-A or to a third 3G_MSC-B’ is cancelled, then the supervision continues, and BSSAP procedures and their related messages shall apply on the E-interface; i) during the intra-3G_MSC-B GSM to UMTS handover execution, if any, the 3G_MSC-B shall queue all outgoing BSSAP or RANAP messages until the communication with the UE/MS is resumed. 8.2.1 Basic Handover procedure requiring a circuit connection between MSC-A and 3G_MSC-B The procedure used for successful Inter-3G_MSC Handover from GSM to UMTS is shown in figure 24. Initiation of the GSM to UMTS handover procedure is described in clause 5. The procedure described in this subclause makes use of messages from the 3GPP TS 08.08 [5], 3GPP TS 25.413 [11] and of the transport mechanism from the Mobile Application Part (MAP) (3GPP TS 29.002 [12]). After an Inter-3G_MSC handover further Intra-3G_MSC handovers may occur on 3G_MSC-B, these handovers will follow the procedures specified in the previous subclauses. 3GPP
  • 48. Release 1999 48 3GPP TS 23.009 V3.14.0 (2003-06) RNS-B/UE/MS UE/MS/BSS-A 3G_MSC-B MSC-A VLR-B A-HO-REQUIRED MAP-Prep-Handover req. MAP-Allocate-Handover-Number req. Iu-RELOCATION-REQUEST Iu-RELOCATION-REQUEST-ACK MAP-Prep-Handover resp. MAP-Send-Handover-Report req. IAM MAP-Send-Handover-Report resp. (1) A-HO-COMMAND ACM MAP-Process-Access-Sig req. A-CLR-CMD/COM Iu-RELOCATION-DETECT MAP-Send-End-Signal req. Iu-RELOCATION-COMPLETE ANSWER End of call RELEASE MAP-Send-End-Signal resp. NOTE 1: Can be sent at any time after the reception of IAM. Figure 24: Basic GSM to UMTS Handover Procedure requiring a circuit connection The GSM to UMTS handover is initiated as described in subclause 6.2.2. (This is represented by A-HO-REQUIRED in figure 24). Upon receipt of the A-HO-REQUIRED from BSS-A, MSC-A shall send a MAP-PREPARE-HANDOVER request to 3G_MSC-B including a complete A-HO-REQUEST message. NOTE: MSC-A shall not send further MAP-PREPARE-HANDOVER requests while a MAP-PREPAREHANDOVER response is pending or before any timeouts. The MAP-PREPARE-HANDOVER request shall carry in the A-HO-REQUEST all information needed by 3G_MSC-B for allocating radio resources in RNS-B, see 3GPP TS 08.08 [5]. The MAP-PREPARE-HANDOVER request shall also carry the identity of the target RNS to which the call is to be handed over, see 3GPP TS 29.002 [12]. 3G_MSC-B will return the MAP-PREPARE-HANDOVER response after having retrieved a Handover Number from its associated VLR (exchange of the messages MAP-allocate-handovernumber request and MAP-send-handover-report request). The Handover Number shall be used for routing the connection of the call from MSC-A to 3G_MSC-B. 3G_MSC-B inserts a transcoder as G711 is assumed between 2G MSC and 3G_MSC-B. If radio resources are available in RNS-B the MAP-PREPARE-HANDOVER response, sent to MSC-A from 3G_MSC-B will contain the complete A-HO-REQUEST-ACK message generated from the IuRELOCATION-REQUEST-ACK received from RNS-B, containing the radio resources definition to be sent by BSS-A to the UE/MS. If the radio resource allocation is not possible, the MAP-PREPARE-HANDOVER response containing an A-HO-FAILURE will be sent to MSC-A. 3G_MSC-B will do the same if a fault is detected on the identity of the cell where the call has to be handed over. 3G_MSC-B simply reports the events related to the dialogue. It is up to MSC-A to decide the action to perform if it receives negative responses or the operation fails due to the expiry of the MAPPREPARE-HANDOVER timer. If an error related to the TCAP dialogue or to the MAP-PREPARE-HANDOVER request is returned from 3G_MSC-B, this will be indicated to MSC-A and MSC-A will terminate the handover attempt. MSC-A shall reject the handover attempt towards BSS-A. The existing connection to the UE/MS shall not be cleared. 3GPP
  • 49. Release 1999 49 3GPP TS 23.009 V3.14.0 (2003-06) When the A-HO-REQUEST-ACK has been received, MSC-A shall establish a circuit between MSC-A and 3G_MSC-B by signalling procedures supported by the network. In figure 24 this is illustrated by the messages IAM (Initial Address Message) and ACM (Address Complete Message) of Signalling System no 7. 3G_MSC-B awaits the capturing of the UE/MS (subclause 6.2.2) on the radio path when the ACM is sent and MSC-A initiates the handover execution when ACM is received (illustrated by the A-HO-COMMAND and described in the subclause 6.2.2). 3G_MSC-B transfers to MSC-A the acknowledgement received from the correct UE/MS (A-HO-DETECT/A-HOCOMPLETE). The Iu-RELOCATION-DETECT, if received, is converted to A-HO-DETECT and transferred to MSC-A using the MAP-PROCESS-ACCESS-SIGNALLING request. The Iu-RELOCATION-COMPLETE, when received from the correct UE/MS, is converted to A-HO-COMPLETE and included in the MAP-SEND-END-SIGNAL request and sent back to MSC-A. The circuit is through-connected in MSC-A when the A-HO-DETECT or the A-HO-COMPLETE is received from 3G_MSC-B. The old radio channel is released when the A-HO-COMPLETE message is received from 3G_MSC-B. The sending of the MAP-SEND-END-SIGNAL request starts the MAP supervision timer for the MAP dialogue between MSC-A and 3G_MSC-B. When the MAP-SEND-END-SIGNAL request including the A-HO-COMPLETE message is received in MSC-A the resources in BSS-A shall be cleared. In order not to conflict with the PSTN/ISDN signalling system(s) used between MSC-A and 3G_MSC-B, 3G_MSC-B must generate an answer signal when Iu-RELOCATION-DETECT/COMPLETE is received. 3G_MSC-B shall release the Handover Number when the circuit between MSC-A and 3G_MSC-B has been established. If the circuit between MSC-A and 3G_MSC-B cannot be established (e.g. an unsuccessful backward message is received instead of ACM). MSC-A terminates the inter3G_MSC handover attempt by sending an appropriate MAP message, for example an ABORT. MSC-A shall retain overall call control until the call is cleared by the fixed subscriber or the UE/MS and there is no further call control functions to be performed (e.g. servicing waiting calls, echo cancellers). When MSC-A clears the call to the UE/MS it also clears the call control functions in MSC-A and sends the MAPSEND-END-SIGNAL response to release the MAP resources in 3G_MSC-B. MSC-A may terminate the procedure at any time by sending an appropriate MAP message to 3G_MSC-B. If establishment of the circuit between MSC-A and 3G_MSC-B has been initiated, the circuit must also be cleared. The GSM to UMTS handover will be aborted by MSC-A if it detects clearing or interruption of the radio path before the call has been established on 3G_MSC-B. 8.2.2 Basic GSM to UMTS Handover procedure not requiring the establishment of a circuit connection between MSC-A and 3G_MSC-B The basic GSM to UMTS handover procedures to be used when no circuit connection is required by MSC-A are similar to those described in subclause 8.2.1 for circuit switched calls. The main differences to the procedures described in subclause 8.2.1 relate to the establishment of circuits between the network entities and the Handover Number allocation. In the case of basic GSM to UMTS handover, MSC-A shall specify to 3G_MSC-B that no Handover Number is required in the MAP-PREPARE-HANDOVER request (see 3GPP TS 29.002 [12]). As for the basic GSM to UMTS handover using a circuit connection, the A-HO-REQUEST is transmitted at the same time. Any subsequent Handover Number allocation procedure will not be invoked until the completion of the basic GSM to UMTS handover procedure (see subclause: Subsequent Channel Assignment using a circuit connection). 3G_MSC-B shall then perform the radio resources allocation as described in subclause 8.2.1. The MAP-PREPARE-HANDOVER response shall be returned to MSC-A including either the translated response of the radio resources allocation request received from RNS-B (A-HOREQUEST-ACK/A-HO-FAILURE). The basic GSM to UMTS handover procedure will continue as described in subclause 8.2.1 except that no circuit connection will be established towards 3G_MSC-B. The relevant case for the basic GSM to UMTS handover without circuit connection is shown in figure 25. As can be seen the major differences to the equivalent figure 24 are the omission of any circuit establishment messaging and the omission of handover number allocation signalling. 3GPP
  • 50. Release 1999 50 UE/MS/BSS-A 3GPP TS 23.009 V3.14.0 (2003-06) RNS-B/UE/MS MSC-A 3G_MSC-B VLR-B A-HO-REQUIRED MAP-Prep-Handover req. Iu-RELOCATION-REQUEST Iu-RELOCATION-REQUEST-ACK A-HO-COMMAND MAP-Prep-Handover resp. MAP-Process-Access-Sig req. A-CLR-CMD/COM End of link Iu-RELOCATION-DETECT MAP-Send-End-Signal req. Iu-RELOCATION-COMPLETE MAP-Send-End-Signal resp. Figure 25: Basic GSM to UMTS Handover Procedure without circuit connection 8.2.3 Procedure for subsequent GSM to UMTS handover requiring a circuit connection After the call has been handed over to MSC-B, if the UE/MS leaves the GSM area of MSC-B during the same call and enters a UTRAN area, subsequent GSM to UMTS handover is necessary in order to continue the connection. The following cases apply: i) the UE/MS moves back to the area of 3G_MSC-A; ii) the UE/MS moves into the area of a third 3G_MSC (3G_MSC-B'). In both cases the call is switched in 3G_MSC-A; the circuit between 3G_MSC-A and MSC-B shall be released after a successful subsequent handover has been performed. 3GPP
  • 51. Release 1999 8.2.3.1 51 3GPP TS 23.009 V3.14.0 (2003-06) Description of subsequent GSM to UMTS handover procedure i): MSC-B to 3G_MSC-A The procedure for successful GSM to UMTS handover from MSC-B back to 3G_MSC-A is shown in figure 26. UE/MS/RNS-B BSS-A/UE/MS 3G_MSC-A MSC-B VLR-B A-HO-REQUIRED MAP-Prep-Sub-Handover req. Iu-RELOCATION-REQUEST Iu-RELOCATION-REQUEST-ACK MAP-Prep-Sub-Handover resp. A-HO-COMMAND Iu-RELOCATION-DETECT Iu-RELOCATION-COMPLETE MAP-Send-End-Signal resp. A-CLR-CMD/COM Release Figure 26: Subsequent GSM to UMTS handover procedure i): successful handover from MSC-B to 3G_MSC-A using a circuit connection The procedure is as follows. MSC-B sends the MAP-PREPARE-SUBSEQUENT-HANDOVER request to 3G_MSC-A indicating the new MSC number (3G_MSC-A number), indicating also the identity of the target RNS where the call has to be handed over and including a complete A-HO-REQUEST message. (NOTE: MSC-B shall not send further MAP-PREPARESUBSEQUENT-HANDOVER requests while a handover attempt is pending or before any timeouts). Since 3G_MSC-A is the call controlling MSC, this MSC needs no Handover Number for routing purposes; 3G_MSC-A can immediately initiate the search for free radio resources. 3G_MSC-A then inserts a transcoder between it’s RNS and the connection to the other party. When radio resources can be assigned, 3G_MSC-A shall return in the MAP-PREPARE-SUBSEQUENT-HANDOVER response the complete A-HO-REQUEST-ACK message generated from the Iu-RELOCATION-REQUEST-ACK received from the RNS-B and possible extra BSSMAP information, amended by 3G_MSC-A due to the possible interworking between the BSSMAP protocol carried on the E-interface and the RANAP protocol used on the Iuinterface. If radio resources cannot be assigned or if a fault is detected on the target cell identity, or the target cell identity in the A-HO-REQUEST is not consistent with the target MSC number, the MAP-PREPARE-SUBSEQUENTHANDOVER response containing an A-HO-FAILURE message shall be given to MSC-B, in addition MSC-B shall maintain the connection with the UE/MS. If the procedure in 3G_MSC-A is successful then MSC-B can request the UE/MS to retune to the new RNS-B on 3G_MSC-A. This is illustrated in figure 26 by the A-HO-COMMAND message. The operation is successfully completed when 3G_MSC-A receives the Iu-RELOCATION-COMPLETE message. After GSM to UMTS handover 3G_MSC-A shall release the circuit to MSC-B. 3G_MSC-A must also terminate the MAP procedure for the basic handover between 3G_MSC-A and MSC-B by sending an appropriate MAP message. MSC-B will clear the resources in BSS-A when the MAP-SEND-END-SIGNAL response is received. 8.2.3.2 Description of subsequent GSM to UMTS handover procedure ii): MSC-B to 3G_MSC-B' The procedure for successful GSM to UMTS handover from MSC-B to 3G_MSC-B' is shown in figure 27. 3GPP
  • 52. Release 1999 52 3GPP TS 23.009 V3.14.0 (2003-06) The procedure consists of two parts: - a subsequent handover from MSC-B back to MSC-A as described in subclause 7.3.1 (the same procedures apply if MSC-A is replaced by 3G_MSC-A); and - a basic GSM to UMTS handover from MSC-A to 3G_MSC-B' as described in subclause 8.2.1. MSC-B sends the MAP-PREPARE-SUBSEQUENT-HANDOVER request to MSC-A indicating a new MSC number (which is the identity of 3G_MSC-B'), indicating also the identity of the target RNS where the call has to be handed over and including a complete A-HO-REQUEST, MSC-A then starts a basic handover procedure towards 3G_MSC-B'. When MSC-A receives the ACM from 3G_MSC-B', MSC-A informs MSC-B that 3G_MSC-B' has successfully allocated the radio resources on RNS-B' side by sending the MAP-PREPARE-SUBSEQUENT-HANDOVER response containing the complete A-HO-REQUEST-ACK generated from the RELOCATION-REQUEST-ACK received from RNS-B' and possible extra BSSMAP information, amended by MSC-A due to the possible interworking between the BSSMAP protocol carried on the E-interface between MSC-A and 3G_MSC-B' and the BSSMAP protocol carried on the E-interface between MSC-A and MSC-B. Now MSC-B can start the procedure on the radio path. For MSC-A the handover is completed when it has received the MAP-SEND-END-SIGNAL REQUEST from 3G_MSC-B' containing the A-HO-COMPLETE generated from Iu-RECOLATION COMPLETE received from the RNS-B'. The circuit between MSC-A and MSC-B is released. MSC-A also sends the MAP-SEND-END-SIGNAL response to MSC-B in order to terminate the original MAP dialogue between MSC-A and MSC-B. MSC-B releases the radio resources when it receives this message. If no radio resources can be allocated by 3G_MSC-B' or no circuit between MSC-A and 3G_MSC-B' can be established or a fault is detected on the target cell identity or the target cell identity in the A-HO-REQUEST is not consistent with the target MSC number, MSC-A informs MSC-B by using the A-HO-FAILURE message included in the MAPPREPARE-SUBSEQUENT-HANDOVER response. MSC-B shall maintain the existing connection with the UE/MS. When the subsequent GSM to UMTS handover is completed, 3G_MSC-B' is considered as 3G_MSC-B. Any further inter-MSC handover is handled as described above for a subsequent handover. 3GPP
  • 53. Release 1999 53 3GPP TS 23.009 V3.14.0 (2003-06) UE/MS/BSS/RNS 3G_MSC-B’ MSC-A MSC-B VLR-B’ VLR-B A-HO-REQUIRED MAP-Prep-Sub-Handover req. MAP-Prepare-Handover req. MAP-Allocate-Handover-Number req. Iu-RELOCATION-REQUEST Iu-RELOCATION-REQUEST-ACK MAP-Prepare-Handover resp. MAP-Send-Handover-Report req. IAM MAP-Send-Handover-Rep. resp. (1) ACM MAP-Prep-Sub-Ho resp. A-HO-COMMAND Iu-RELOCATION-DETECT MAP-Process-Access-Signalling req. Iu-RELOCATION-COMPLETE MAP-Send-End-Signal req. Answer Release MAP-Send-End-Signal resp. A-CLR-CMD/COM (end of call) Release MAP-Send-End-Signal resp. NOTE 1: Can be sent at any time after the reception of IAM. Figure 27: Subsequent GSM to UMTS handover procedure ii): Successful handover from MSC-B to 3G_MSC-B' requiring a circuit connection 8.2.4 Procedure for subsequent GSM to UMTS handover not requiring a circuit connection As for the subsequent GSM to UMTS handover with a circuit connection, the same two cases of subsequent handover apply: i) the UE/MS moves back to the area of 3G_MSC-A; ii) the UE/MS moves into the area of a third 3G_MSC (3G_MSC-B'). 3GPP
  • 54. Release 1999 8.2.4.1 54 3GPP TS 23.009 V3.14.0 (2003-06) Description of subsequent GSM to UMTS handover procedure without circuit connection i): MSC-B to 3G_MSC-A The procedure for successful GSM to UMTS handover from MSC-B back to 3G_MSC-A without circuit connection is shown in figure 28. The only difference with the figure 26, is that no circuit release is needed between 3G_MSC-A and MSC-B. UE/MS/RNS-B BSS-A/UE/MS 3G_MSC-A MSC-B VLR-B A-HO-REQUIRED MAP-Prep-Sub-Handover req. Iu-RELOCATION-REQUEST Iu-RELOCATION-REQUEST-ACK MAP-Prep-Sub-Handover resp. A-HO-COMMAND Iu-RELOCATION-DETECT Iu-RELOCATION-COMPLETE MAP-Send-End-Signal resp. A-CLR-CMD/COM Figure 28: Subsequent GSM to UMTS handover procedure i): Successful handover from MSC-B to 3G_MSC-A not requiring a circuit connection 8.2.4.2 Description of subsequent GSM to UMTS handover procedure without circuit connection ii): MSC-B to 3G_MSC-B' The procedure for successful GSM to UMTS handover from MSC-B to 3G_MSC-B' is shown in figure 29. The procedure consists of two parts: - a subsequent handover from MSC-B back to MSC-A as described in subclause 7.4.1 (the same procedures apply if MSC-A is replaced by 3G_MSC-A); and - a basic GSM to UMTS handover from MSC-A to 3G_MSC-B' as described in subclause 8.2.2. The only difference to the equivalent figure 27 is the omission of the circuit and handover number allocation signallings. 3GPP
  • 55. Release 1999 55 3GPP TS 23.009 V3.14.0 (2003-06) UE/MS/BSS/RNS 3G_MSC-B’ MSC-A MSC-B VLR-B’ VLR-B A-HO-REQUIRED MAP-Prep-Sub-Handover req. MAP-Prepare-Handover req. Iu-RELOCATION-REQUEST Iu-RELOCATION-REQUEST-ACK MAP-Prepare-Handover resp. MAP-Prep-Sub-Ho resp. A-HO-COMMAND Iu-RELOCATION-DETECT MAP-Process-Access-Signalling req. Iu-RELOCATION_COMPLETE MAP-Send-End-Signal req. MAP-Send-End-Signal resp. A-CLR-CMD/COM (end of link) MAP-Send-End-Signal resp. Figure 29: Subsequent GSM to UMTS handover procedure ii): Successful handover from MSC-B to 3G_MSC-B' without circuit connection 8.3 SRNS Relocation The following subclauses describe two options for the Basic and Subsequent Relocation procedures. The first, as described in subclauses 8.3.1 and 8.3.3 respectively, provides for a circuit connection between 3G_MSC-A and 3G_MSC-B. The second, as described in subclauses 8.3.2 and 8.3.4 respectively, provides for a Basic and Subsequent Relocation without the provision of a circuit connection between 3G_MSC-A and 3G_MSC-B. In all the above mentioned subclauses, the following principles apply: a) during the relocation resource allocation, except for the messages explicitly indicated in b and c below, only the relocation related messages that are part of the applicable RANAP subset - as defined in 3GPP TS 29.108 [15] shall be transferred on the E-interface; b) the trace related messages that are part of the applicable RANAP subset - as defined in 3GPP TS 29.108 [15] can be sent by the 3G_MSC-A on the E-interface after successful relocation resource allocation. In the subclauses 8.3.1 and 8.3.2, it is however allowed at basic relocation initiation on the E-Interface to transfer one trace invocation related message that is part of the applicable RANAP subset - as defined in 3GPP TS 29.108 [15] - together with the applicable relocation related message. The applicable relocation related message shall always appear as the first message; c) during the handover resource allocation for subsequent inter-MSC inter-system handover according to subclauses 8.3.3 and 8.3.4, it is allowed to transfer either DTAP or RANAP Direct Transfer messages on the EInterface between MSC-A and 3G_MSC-B. RANAP Direct Transfer messages shall be used for this purpose if and only if the basic handover procedure was an inter MSC SRNS relocation; 3GPP
  • 56. Release 1999 56 3GPP TS 23.009 V3.14.0 (2003-06) d) during the relocation execution, i.e. while the UE is not in communication with the network, the 3G_MSC-A shall queue all outgoing RANAP or BSSAP messages until the communication with the UE is resumed; e) during the execution of a basic inter-MSC SRNS relocation to 3G_MSC-B or a subsequent inter-MSC SRNS relocation to a third 3G-MSC-B’, only the relocation related messages and the Iu-Release-Request message that are part of the applicable RANAP subset - as defined in 3GPP TS 29.108 [15] – may be sent by the target MSC on the E-interface; f) during a subsequent inter-MSC SRNS relocation back to 3G_MSC-A or to a third 3G_MSC-B’, 3G_MSC-B may initiate either an Iu-Release-Request procedure or an A-Clear-Request procedure on the E-interface. An IuRelease-Request procedure shall be initiated only if the basic handover procedure was an inter-MSC SRNS relocation; g) finally, during supervision, i.e. while the UE is not in the area of 3G_MSC-A after a successful Inter-3G_MSC relocation, the subset of RANAP procedures and their related messages - as defined in 3GPP TS 29.108 [15] shall apply on the E-Interface. As an exception to this rule, 3G_MSC-B shall notify 3G_MSC-A of a successfully completed subsequent intra-MSC-B intra GSM or inter-system handover by using the Internal Handover Indication procedure as specified in 3GPP TS 09.08 [7]. Furthermore, in case of a subsequent interMSC intra GSM or inter-system handover back to 3G_MSC-A or to a third 3G_MSC-B’, during the handover resource allocation, the handover and trace related messages that are part of the applicable BSSAP subset - as defined in 3GPP TS 09.08 [7] - shall be transferred on the E-interface (see list items a and b in clause 7, subclause 8.1, and 8.2, respectively). If a subsequent inter-MSC handover/relocation back to 3G_MSC-A or to a third 3G_MSC-B’ is cancelled, then the supervision continues, and RANAP procedures and their related messages shall apply on the E-interface. NOTE: A subsequent inter-MSC intra GSM or GSM to UMTS inter-system handover back to 3G_MSC-A or to a third 3G_MSC-B’ can occur, e.g., if after the basic inter-MSC SRNS relocation to 3G_MSC-B the MS performed a subsequent intra-3G_MSC-B UMTS to GSM inter-system handover; h) during the intra-3G_MSC-B relocation execution, if any, the 3G_MSC-B shall queue all outgoing RANAP messages until the communication with the UE is resumed; i) after successful completion of the Intra-3G_MSC-B relocation, if 3G_MSC-B or 3G-MSC-B’ has previously received an order to perform location reporting at change of Service Area from 3G_MSC-A, it shall act as specified in subclause 6.2.3. 8.3.1 Basic relocation procedure requiring a circuit connection between 3G_MSC-A and 3G_MSC-B The procedure used for successful Inter-3G_MSC SRNS relocation is shown in figure 30. Initiation of the relocation procedure is described in clause 5. The procedure described in this subclause makes use of messages from the 3GPP TS 25.413 [11] and of the transport mechanism from the Mobile Application Part (MAP) (3GPP TS 29.002 [12]). After an Inter-3G_MSC SRNS relocation further Intra-3G_MSC relocations may occur on 3G_MSC-B, these relocations will follow the procedures specified in a previous clause. 3GPP
  • 57. Release 1999 57 RNS-A 3GPP TS 23.009 V3.14.0 (2003-06) RNS-B 3G_MSC-A 3G_MSC-B VLR-B IU-RELOC-REQUIRED MAP-Prep-Handover req. MAP-Allocate-Handover-Number req. IU-RELOC-REQUEST IU-RELOC-REQUEST-ACK MAP-Prep-Handover resp. MAP-Send-Handover-Report req. IAM MAP-Send-Handover-Report resp. (1) IU-RELOC-COMMAND ACM MAP-Process-Access-Sig req. IU-REL-CMD/COM IU-RELOC-DETECT MAP-Send-End-Signal req. IU-RELOC-COMPLETE ANSWER End of call RELEASE MAP-Send-End-Signal resp. NOTE 1: Can be sent at any time after the reception of IAM. Figure 30: Basic SRNS Relocation Procedure requiring a circuit connection 8.3.1.1 With one circuit connection The relocation is initiated as described in subclause 6.2.3. (This is represented by IU-RELOC-REQUIRED in figure 30). Upon receipt of the IU-RELOC-REQUIRED from RNS-A, 3G_MSC-A shall send a MAP-PREPARE-HANDOVER request to 3G_MSC-B including a complete IU-RELOC-REQUEST message. (NOTE: 3G_MSC-A shall not send further MAP-PREPARE-HANDOVER requests while a MAP-PREPARE-HANDOVER response is pending or before any timeouts). The MAP-PREPARE-HANDOVER request shall carry in the IU-RELOC-REQUEST all information needed by 3G_MSC-B for allocating radio resources in the case of SRNS relocation without Iur interface, see 3GPP TS 25.413 [11]. 3G_MSC-A shall configure the RANAP RAB parameters according to the default UMTS AMR codec (see [10] for description of how to determine the default codec type) and indicate to the UE if this codec is different to the current selected codec. 3GPP
  • 58. Release 1999 58 3GPP TS 23.009 V3.14.0 (2003-06) MAP-PREPARE-HANDOVER request shall also carry the identity of the target RNS to which the call is to be relocated, see 3GPP TS 29.002. 3G_MSC-B will return the MAP-PREPARE-HANDOVER response after having retrieved one or several Handover Numbers from its associated VLR (exchange of the messages MAP-allocatehandover-number request and MAP-send-handover-report request), 3G_MSC-B shall connect a transcoder. The Handover Numbers shall be used for routing the connections of the calls from 3G_MSC-A to 3G_MSC-B. If radio resources are available in 3G_MSC-B, the MAP-PREPARE-HANDOVER response sent to 3G_MSC-A will contain the complete IU-RELOC-REQUEST-ACKNOWLEDGE message received from RNS-B, containing the radio resources definition to be sent by RNS-A to the UE (in case of relocation without Iur interface) and possible extra RANAP information, amended by 3G_MSC-B due to the possible interworking between the RANAP protocol carried on the Einterface and the RANAP protocol used on the Iu-interface. If the radio resource allocation is not possible, the MAPPREPARE-HANDOVER response containing an IU-RELOCATION-FAILURE will be sent to 3G_MSC-A. 3G_MSC-B will do the same if a fault is detected on the identity of the RNS where the call has to be relocated. 3G_MSC-B simply reports the events related to the dialogue. It is up to 3G_MSC-A to decide the action to perform if it receives negative responses or the operation fails due to the expiry of the MAP-PREPARE-HANDOVER timer. If an error related to the TCAP dialogue or to the MAP-PREPARE-HANDOVER request is returned from 3G_MSC-B, this will be indicated to 3G_MSC-A and 3G_MSC-A will terminate the relocation attempt. The existing connection to the UE shall not be cleared. When the IU-RELOC-REQUEST-ACKNOWLEDGE has been received, 3G_MSC-A shall establish a circuit between 3G_MSC-A and 3G_MSC-B by signalling procedures supported by the network. In figure 30 this is illustrated by the messages IAM (Initial Address Message) and ACM (Address Complete Message) of Signalling System no 7. 3G_MSC-B awaits the capturing of the UE (subclause 6.2.3) on the radio path when the ACM is sent and 3G_MSC-A initiates the relocation execution when ACM is received (illustrated by the IU-RELOC-COMMAND and described in the subclause 6.2.3). 3G_MSC-A shall remove the transcoder between the MSC and other party. 3G_MSC-B transfers to 3G_MSC-A the acknowledgement received from the correct UE (IU-RELOC-DETECT/IURELOC-COMPLETE). The IU-RELOC-DETECT, if received, is transferred to 3G_MSC-A using the MAPPROCESS-ACCESS-SIGNALLING request. The IU-RELOC-COMPLETE, when received from the correct UE, is included in the MAP-SEND-END-SIGNAL request and sent back to 3G_MSC-A. The circuit is through connected in 3G_MSC-A when the IU-RELOC-DETECT or the IU-RELOC-COMPLETE is received from 3G_MSC-B. The old radio resources are released when the IU-RELOC-COMPLETE message is received from 3G_MSC-B. The sending of the MAP-SEND-END-SIGNAL request starts the MAP supervision timer for the MAP dialogue between 3G_MSC-A and 3G_MSC-B. When the MAP-SEND-END-SIGNAL request including the IU-RELOC-COMPLETE message is received in 3G_MSC-A, the resources in RNS-A shall be released. In order not to conflict with the PSTN/ISDN signalling system(s) used between 3G_MSC-A and 3G_MSC-B, 3G_MSC-B must generate an answer signal when IU-RELOC-DETECT/COMPLETE is received. 3G_MSC-B shall release the Handover Number when the circuit between 3G_MSC-A and 3G_MSC-B has been established. If the circuit between 3G_MSC-A and 3G_MSC-B cannot be established, (e.g. an unsuccessful backward message is received instead of ACM) 3G_MSC-A terminates the inter-3G_MSC relocation attempt by sending an appropriate MAP message, for example an ABORT. 3G_MSC-A shall retain overall call control until the call is cleared by the fixed subscriber or the UE and there is no further call control functions to be performed (e.g. servicing waiting calls, echo cancellers). When 3G_MSC-A clears the call to the UE it also clears the call control functions in 3G_MSC-A and sends the MAPSEND-END-SIGNAL response to release the MAP resources in 3G_MSC-B. 3G_MSC-A may terminate the procedure at any time by sending an appropriate MAP message to 3G_MSC-B. If establishment of the circuit between 3G_MSC-A and 3G_MSC-B has been initiated, the circuit must also be cleared. The relocation will be aborted by 3G_MSC-A if it detects release or interruption of the radio path before the call has been established on 3G_MSC-B. 3GPP
  • 59. Release 1999 8.3.1.2 8.3.1.2.1 59 3GPP TS 23.009 V3.14.0 (2003-06) With multiple circuit connections (Optional functionality) 3G_MSC-B does not support multiple bearers If 3G_MSC-A supports the optional supplementary service Multicall (See 3GPP TS 23.135), 3G_MSC-A shall have the following functionality additionally to the description in section 8.3.1.1. Upon receipt of the IU-RELOCATION-REQUIRED from RNS-A, 3G_MSC-A generates IU-RELOCATIONREQUEST and sends a MAP-PREPARE-HANDOVER request to 3G_MSC-B including the IU-RELOCATIONREQUEST message, which may include multiple bearers. If 3G_MSC-A receives an indication that 3G_MSC-B does not support multiple bearers, 3G_MSC-A shall select one bearer to be handed over if the UE is engaged with multiple bearers. 3G_MSC-A reconstructs IU-RELOCATION-REQUEST and sends again a MAP-PREPARE-HANDOVER request to 3G_MSC-B including the IU-RELOCATION-REQUEST message, which includes only the selected bearer. When MAP-PREPARE-HANDOVER response including an IU-RELOCATION-REQUEST-ACK is received from 3G_MSC-B, 3G_MSC-A sends IU-RELOCATION-COMMAND, which indicates the bearers not to be handed over as bearers to be released, to RNS-A. After 3G_MSC-A receives MAP-SEND-END-SIGNAL request from 3G_MSC-B, 3G_MSC-A shall release calls via 3G_MSC-B, which has been carried by the bearers not to be handed over, and then 3G_MSC-A sends IU-RELEASECOMMAND to RNS-A. 8.3.1.2.2 3G_MSC-B supports multiple bearers If 3G_MSC-A and 3G_MSC_B support the optional supplementary service Multicall (See 3GPP TS 23.135), 3G_MSCA and 3G_MSC-B shall have the following functionality additionally to the description in section 8.3.1.1. Upon receipt of the IU-RELOCATION-REQUIRED from RNS-A, 3G_MSC-A generates IU-RELOCATIONREQUEST and sends a MAP-PREPARE-HANDOVER request to 3G_MSC-B including the IU-RELOCATIONREQUEST message, which may include multiple bearers. When MAP-PREPARE-HANDOVER request including an IU-RELOCATION-REQUEST message is received by the 3G_MSC-B and the number of bearers included in the IU-RELOCATION-REQUEST message has exceeded the maximum number of bearers supported by 3G_MSC-B, the 3G_MSC-B shall select several bearers so that the number of bearers will fulfil the range of 3G_MSC-B capability. In this case 3G_MSC-B shall reconstruct IU-RELOCATIONREQUEST message to cope with the capability of 3G_MSC-B. The 3G_MSC-B shall retrieve multiple Handover Numbers from its associated VLR (exchange of the messages MAP-allocate-handover-number request and MAP-sendhandover-report request several times). The number of Handover Numbers depends on the number of RAB IDs in the reconstructed IU-RELOCATION-REQUEST. After the completion of Handover Number allocation 3G_MSC-B may select several bearers and reconstruct IURELOCATION-REQUEST again if the number of successfully allocated Handover Numbers is less than the number of required bearers, and sends IU-RELOCATION-REQUEST to RNS-B. After the reception of IU-RELOCATION-REQUEST-ACK from RNS-B, the 3G_MSC-B shall generate Relocation Number List, which includes couples of RAB ID (See 3GPP TS 25.413 [11]) and Handover Number successfully allocated. Then the 3G_MSC-B sends MAP-PREPARE-HANDOVER response including Relocation Number List back to the 3G_MSC-A. Upon receipt of the MAP-PREPARE-HANDOVER response 3G_MSC-A shall establish circuits between 3G_MSC-A and 3G_MSC-B by signalling procedures supported by the network according to the Relocation Number List. When 3G_MSC-A receives all the results from attempted circuits (the results may be successful ACM message or unsuccessful backward message for each attempt) and if at least one circuit has been successfully established, 3G_MSC-A sends IU-RELOCATION-COMMAND, which indicates the bearers failed to set up in RNS-B and the bearers associated with circuits which has failed to set up as bearers to be released, to RNS-A. After 3G_MSC-A receives MAP-SEND-END-SIGNAL request from 3G_MSC-B, 3G_MSC-A shall release calls via 3G_MSC-B, which has been carried by the bearers failed to set up in RNS-B and the bearers associated with circuits which has failed to set up, and then 3G_MSC-A sends IU-RELEASE-COMMAND to RNS-A. If no circuit connection has been successfully established 3G_MSC-A terminates the inter-3G_MSC relocation attempt by sending an appropriate MAP massage, for example ABORT. 3GPP
  • 60. Release 1999 8.3.2 60 3GPP TS 23.009 V3.14.0 (2003-06) Basic relocation procedure not requiring the establishment of a circuit connection between 3G_MSC-A and 3G_MSC-B The basic SRNS relocation procedures to be used when no circuit connection is required by 3G_MSC-A are similar to those described in subclause 8.3.1 for circuit switched calls. The main differences to the procedures described in subclause 8.3.1 relate to the establishment of circuits between the network entities and the Handover Number allocation. In the case of basic relocation, 3G_MSC-A shall specify to 3G_MSC-B that no Handover Number is required in the MAP-PREPARE-HANDOVER request (see 3GPP TS 29.002 [12]). As for the basic relocation using a circuit connection, the IU-RELOC-REQUEST is transmitted at the same time together with the identity of the target RNS to which the call is to be relocated. Any subsequent Handover Number allocation procedure will not be invoked until the completion of the basic relocation procedure (see clause: Subsequent Channel Assignment using a circuit connection). 3G_MSC-B shall then perform the radio resources allocation as described in subclause 8.3.1 if applicable. The MAPPREPARE-HANDOVER response shall be returned to 3G_MSC-A including either the response of the radio resources allocation request received from RNS-B (IU-RELOC-REQUEST-ACKNOWLEDGE/IU-RELOC-FAILURE with possible extra RANAP information. This extra information is amended by 3G_MSC-B due to the possible interworking between the RANMAP protocol carried on the E-interface and the RANAP protocol used on the Iu-interface). The basic relocation procedure will continue as described in subclause 8.3.1 except that no circuit connection will be established towards 3G_MSC-B. The relevant case for the basic relocation without circuit connection is shown in figure 31. As can be seen the major differences to the equivalent figure 30 are the omission of any circuit establishment messaging and the omission of handover number allocation signalling. RNS-A RNS-B 3G MSC-A 3G MSC-B IU-RELOC-REQUIRED MAP-Prep-Handover req. IU-RELOC-REQUEST IU-RELOC-REQUEST-ACK MAP-Prep-Handover resp. IU-RELOC-COMMAND MAP-Process-Access-Sig req. IU-REL-CMD/COM IU-RELOC-DETECT MAP-Send-End-Signal req. IU-RELOC-COMPLETE End of link MAP-Send-End-Signal resp. Figure 31: Basic SRNS relocation procedure without a circuit connection 3GPP VLR-B
  • 61. Release 1999 8.3.3 61 3GPP TS 23.009 V3.14.0 (2003-06) Procedure for subsequent relocation requiring a circuit connection After the call has been relocated to 3G_MSC-B, if the UE leaves the area of 3G_MSC-B during the same call, subsequent relocation is necessary in order to continue the connection when no Iur interface exists between the involved RNSs, or to optimise the transmission path when the Iur interface is used. The following cases apply: i) the UE moves back to the area of 3G_MSC-A; ii) the UE moves into the area of a third 3G_MSC (3G_MSC-B'). In both cases the call is switched in 3G_MSC-A; the circuit between 3G_MSC-A and 3G_MSC-B shall be released after a successful subsequent relocation has been performed. If 3G_MSC-A is replaced by MSC-A in the procedures, then a subsequent relocation from 3G_MSC-B to 3G_MSC-B' shall not be possible since MSC-A does not support the RANAP protocol. 8.3.3.1 Description of subsequent relocation procedure i): 3G_MSC-B to 3G_MSC-A The procedure for successful relocation from 3G_MSC-B back to 3G_MSC-A is shown in figure 32. RNS-B RNS-A 3G_MSC-A 3G_MSC-B VLR-B Iu-RELOCATIONREQUIRED MAP-Prep-Sub-Handover req. Iu-RELOCATIONREQUEST Iu-RELOCATIONREQUEST-ACK MAP-Prep-Sub-Handover resp. Iu-RELOCATIONCOMMAND MAP-Send-End-Signal resp. Iu-RELEASECMD/COM Iu-RELOCATIONDETECT Iu-RELOCATIONCOMPLETE Release Figure 32: Subsequent relocation procedure i) successful relocation from 3G_MSC-B to 3G_MSC-A using a circuit connection 8.3.3.1.1 With one circuit connection The procedure is as follows. 3G_MSC-B sends the MAP-PREPARE-SUBSEQUENT-HANDOVER request to 3G_MSC-A indicating the new 3G_MSC number (3G_MSC-A number), indicating also the identity of the target RNS where the call has to be relocated and including a complete IU-RELOC-REQUEST message. NOTE: 3G_MSC-B shall not send further MAP-PREPARE-SUBSEQUENT-HANDOVER requests while a relocation attempt is pending or before any timeouts. Since 3G_MSC-A is the call controlling 3G_MSC, this 3G_MSC needs no Handover Number for routing purposes; 3G_MSC-A can immediately initiate the relocation towards the target RNS. When relocation can be initiated, 3G_MSC-A shall return in the MAP-PREPARE-SUBSEQUENT-HANDOVER response the complete IU-RELOC-REQUEST-ACKNOWLEDGE message received from the RNS-B and possible extra RANAP information, amended by 3G_MSC-A due to the possible interworking between the RANAP protocol carried on the E-interface and the RANAP protocol used on the Iu-interface. If a radio resource cannot be assigned or if a fault is detected on the target RNS identity, or the target RNS identity in the IU-RELOC-REQUEST is not consistent with the target 3G_MSC number, the MAP-PREPARE-SUBSEQUENT-HANDOVER response containing an IU- 3GPP
  • 62. Release 1999 62 3GPP TS 23.009 V3.14.0 (2003-06) RELOC-FAILURE message shall be given to 3G_MSC-B, in addition 3G_MSC-B shall maintain the connection with the UE. If the procedure in 3G_MSC-A is successful then 3G_MSC-B can request the UE to retune to the new RNS-B on 3G_MSC-A in the case of relocation without Iur interface, or request RNS-B to become serving RNS in the case of relocation with Iur interface. This is illustrated in figure 32 by the IU-RELOC-COMMAND message. The operation is successfully completed when 3G_MSC-A receives the IU-RELOC-COMPLETE message. 3G_MSC-A shall insert a transcoder at successful subsequent relocation back to 3G_MSC-A. After relocation 3G_MSC-A shall release the circuit to 3G_MSC-B. 3G_MSC-A must also terminate the MAP procedure for the basic relocation between 3G_MSC-A and 3G_MSC-B by sending an appropriate MAP message. 3G_MSC-B will release the resources in RNS-A when the MAP-SEND-ENDSIGNAL response is received. 8.3.3.1.2 With multiple circuit connections (Optional functionality) If 3G_MSC-A and 3G_MSC_B support the optional supplementary service Multicall (See 3GPP TS 23.135), 3G_MSCA and 3G_MSC-B shall have the following functionality additionally to the description in section 8.3.3.1.1. Upon receipt of the IU-RELOCATION-REQUIRED from RNS-A, 3G_MSC-B generates IU-RELOCATIONREQUEST which may include several bearers and sends it to 3G_MSC-A over MAP-PREPARE-SUBSEQUENTHANDOVER request. 3G_MSC-A sends IU-RELOCATION-REQUEST to RNS-B and receives IU-RELOCATION-REQUEST-ACK. When MAP-PREPARE-SUBSEQUENT-HANDOVER response is received from 3G_MSC-A, 3G_MSC-B sends IURELOCATION-COMMAND, which indicates the bearers failed to set up in RNS-B as bearers to be released, to RNSA. After 3G_MSC-A receives IU-RELOCATION-COMPLETE message from RNS-B, 3G_MSC-A shall release calls via RNS-B, which has been carried by the bearers failed to set up in RNS-B, and then 3G_MSC-A sends MAP-SENDEND-SIGNAL response to 3G_MSC-B. 8.3.3.2 Description of subsequent relocation procedure ii): 3G_MSC-B to 3G_MSC-B' The procedure for successful relocation from 3G_MSC-B to 3G_MSC-B' is shown in figure 33. The procedure consists of two parts: - a subsequent relocation from 3G_MSC-B back to 3G_MSC-A as described in subclause 8.3.3.1; and - a basic relocation from 3G_MSC-A to 3G_MSC-B' as described in subclause 8.3.1. 8.3.3.2.1 With one circuit connection 3G_MSC-B sends the MAP-PREPARE-SUBSEQUENT-HANDOVER request to 3G_MSC-A indicating a new 3G_MSC number (which is the identity of 3G_MSC-B'), indicating also the target RNS identity and including a complete IU-RELOC-REQUEST, 3G_MSC-A then starts a basic relocation procedure towards 3G_MSC-B'. When 3G_MSC-A receives the ACM from 3G_MSC-B', 3G_MSC-A informs 3G_MSC-B that 3G_MSC-B' has successfully allocated the radio resources on RNS-B' side by sending the MAP-PREPARE-SUBSEQUENTHANDOVER response containing the complete IU-RELOC-REQUEST-ACKNOWLEDGE received from RNS-B' and possible extra RANAP information, amended by 3G_MSC-A due to the possible interworking between the RANAP protocol carried on the E-interface between 3G_MSC-A and 3G_MSC-B' and the RANAP protocol carried on the E-interface between 3G_MSC-A and 3G_MSC-B. Now 3G_MSC-B can start the procedure on the radio path if needed. For 3G_MSC-A the relocation is completed when it has received the MAP-SEND-END-SIGNAL REQUEST from 3G_MSC-B'containing the IU-RELOC-COMPLETE received from the RNS-B'. The circuit between 3G_MSC-A and 3G_MSC-B is released. 3G_MSC-A also sends the MAP-SEND-END-SIGNAL response to 3G_MSC-B in order to terminate the original MAP dialogue between 3G_MSC-A and 3G_MSC-B. 3G_MSC-B releases the radio resources when it receives this message. 3GPP
  • 63. Release 1999 63 3GPP TS 23.009 V3.14.0 (2003-06) If no radio resource can be allocated by 3G_MSC-B' or no circuit between 3G_MSC-A and 3G_MSC-B' can be established or a fault is detected on the target RNS identity or the target RNS identity in the IU-RELOC-REQUEST is not consistent with the target 3G_MSC number, 3G_MSC-A informs 3G_MSC-B by using the IU-RELOC-FAILURE message included in the MAP-PREPARE-SUBSEQUENT-HANDOVER response. 3G_MSC-B shall maintain the existing connection with the UE. When the subsequent relocation is completed, 3G_MSC-B' is considered as 3G_MSC-B. Any further inter-3G_MSC relocation is handled as described above for a subsequent relocation. 8.3.3.2.2 With multiple circuit connections (Optional functionality) If 3G_MSC-A and 3G_MSC-B support the optional supplementary service Multicall (See 3GPP TS 23.135), 3G_MSCA and 3G_MSC-B shall have the following functionality additionally to the description in section 8.3.3.2.1. Upon receipt of the IU-RELOCATION-REQUIRED from RNS-B 3G_MSC-B generates an IU-RELOCATIONREQUEST message which may include multiple bearer and sends it to 3G_MSC-A over MAP-PREPARESUBSEQUENT-HANDOVER request. Upon receipt of the MAP-PREPARE-SUBSEQUENT-HANDOVER request from 3G_MSC-B, 3G_MSC-A starts a basic relocation procedure towards 3G_MSC-B'. 8.3.3.2.2.1 3G_MSC-B' does not support multiple bearers If 3G_MSC-A receives an indication that 3G_MSC-B' does not support multiple bearers, 3G_MSC-A shall select one bearer to be handed over. 3G_MSC-A reconstructs IU-RELOCATION-REQUEST and sends again a MAP-PREPAREHANDOVER request to 3G_MSC-B' including the IU-RELOCATION-REQUEST message, which includes only the selected bearer. Upon receipt of MAP-PREPARE-HANDOVER response from 3G_MSC-B', 3G_MSC-A shall reconstructs IU-RELOCATION-REQUEST-ACK to indicate the bearers not to be handed over as the bearers failed to set up in IU-RELOCATION-REQUEST-ACK and send it over MAP-PREPARE-SUBSEQUENT-HANDOVER response to 3G_MSC-B. When MAP-PREPARE-SUBSEQUENT-HANDOVER response is received from 3G_MSC-A 3G_MSC-B sends IURELOCATION-COMMAND, which indicates the bearers failed to set up as bearers to be released, to RNS-A. After 3G_MSC-A receives MAP-SEND-END-SIGNAL request from 3G_MSC-B', 3G_MSC-A shall release calls via 3G_MSC-B', which has been carried by the bearers failed to set up, and then 3G_MSC-A sends MAP-SEND-ENDSIGNAL response to 3G_MSC-B. 8.3.3.2.2.2 3G_MSC-B' supports multiple bearers If some of circuit connections failed to set up between 3G_MSC-A and 3G_MSC-B', 3G_MSC-A shall reconstruct IURELOCATION-REQUEST-ACK message so that the IU-RELOCATION-REQUEST-ACK includes only the bearers which have successfully established circuit connection and sends it to 3G_MSC-B over MAP-PREPARESUBSEQUENT-HANDOVER response. When MAP-PREPARE-SUBSEQUENT-HANDOVER response is received from 3G_MSC-A 3G_MSC-B sends IURELOCATION-COMMAND, which indicates the bearers failed to set up as bearers to be released, to RNS-A. After 3G_MSC-A receives MAP-SEND-END-SIGNAL request from 3G_MSC-B', 3G_MSC-A shall release calls via 3G_MSC-B', which has been carried by the bearers failed to set up, and then 3G_MSC-A sends MAP-SEND-ENDSIGNAL response to 3G_MSC-B. 3GPP
  • 64. Release 1999 64 RNS-B 3GPP TS 23.009 V3.14.0 (2003-06) RNS-B' 3G_MSC-B' 3G_MSC-A 3G_MSC-B VLR-B' VLR-B Iu-RELOCATIONREQUIRED MAP-Prep-Sub-Handover req. MAP-Prepare-Handover req. MAP-Prepare-Handover resp. MAP-Allocate-Handover-Number req. Iu-RELOCATIONREQUEST Iu-RELOCATIONREQUEST-ACK MAP-Send-Handover-Report req. IAM MAP-Send-Handover-Rep. resp. (1) ACM MAP-Prep-Sub-Ho resp. Iu-RELOCATION-CMD Iu-RELOCATIONDETECT MAP-Process-Access-Signalling req. Iu-RELOCATIONCOMPLETE MAP-Send-End-Signal req. Answer Release MAP-Send-End-Signal resp. Iu-RELEASE-CMD/COM (end of call) Release MAP-Send-End-Signal resp. NOTE 1: Can be sent at any time after the reception of IAM. Figure 33: Subsequent relocation procedure ii) Successful SRNS relocation from 3G_MSC-B to 3G_MSC-B' requiring a circuit connection 8.3.4 Procedure for subsequent relocation not requiring a circuit connection As for the subsequent relocation with a circuit connection between 3G_MSC-A and 3G_MSC-B, the same two cases of subsequent relocation apply: i) the UE moves back to the area of 3G_MSC-A; ii) the UE moves into the area of a third 3G_MSC (3G_MSC-B'). If 3G_MSC-A is replaced by MSC-A in the procedures, then a subsequent relocation from 3G_MSC-B to 3G_MSC-B' shall not be possible since MSC-A does not support the RANAP protocol. 3GPP
  • 65. Release 1999 8.3.4.1 65 3GPP TS 23.009 V3.14.0 (2003-06) Description of subsequent relocation procedure i): 3G_MSC-B to 3G_MSC-A The procedure for successful relocation from 3G_MSC-B back to 3G_MSC-A without circuit connection is shown in figure 34. The only difference with the figure 32 is that no circuit release is needed between 3G_MSC-A and 3G_MSC-B. RNS-B RNS-A 3G_MSC-A 3G_MSC-B VLR-B Iu-RELOCATIONREQUIRED MAP-Prep-Sub-Handover req. Iu-RELOCATIONREQUEST Iu-RELOCATIONREQUEST-ACK MAP-Prep-Sub-Handover resp. Iu-RELOCATIONCOMMAND MAP-Send-End-Signal resp. Iu-RELEASECMD/COM Iu-RELOCATIONDETECT Iu-RELOCATIONCOMPLETE Figure 34: Subsequent relocation procedure i) successful relocation from 3G_MSC-B to 3G_MSC-B not requiring a circuit connection 8.3.4.2 Description of subsequent relocation procedure ii): 3G_MSC-B to 3G_MSC-B'' The procedure for successful relocation from 3G_MSC-B to 3G_MSC-B' is shown in figure 35. The procedure consists of two parts: - a subsequent relocation from 3G_MSC-B back to 3G_MSC-A as described in subclause 8.3.4.1; and - a basic relocation from 3G_MSC-A to 3G_MSC-B' as described in subclause 8.3.2. The only difference to the equivalent figure 33 is the omission of the circuit and handover number allocation signallings. 3GPP
  • 66. Release 1999 66 RNS-B 3GPP TS 23.009 V3.14.0 (2003-06) RNS-B' 3G_MSC-B' 3G_MSC-A 3G_MSC-B VLR-B' VLR-B Iu-RELOCATIONREQUIRED MAP-Prep-Sub-Handover req. MAP-Prepare-Handover req. MAP-Prepare-Handover resp. Iu-RELOCATIONREQUEST Iu-RELOCATIONREQUEST-ACK MAP-Prep-Sub-Ho resp. Iu-RELOCATION-CMD Iu-RELOCATIONDETECT MAP-Process-Access-Signalling req. Iu-RELOCATIONCOMPLETE MAP-Send-End-Signal req. MAP-Send-End-Signal resp. Iu-RELEASE-CMD/COM (end of link) MAP-Send-End-Signal resp. Figure 35: Subsequent relocation procedure ii) Successful SRNS relocation from 3G_MSC-B to 3G_MSC-B' not requiring a circuit connection 9 Detailed procedures in MSC-A 9.1 BSS/MSC and MS/MSC procedures in MSC-A (functional unit 1) The handover procedures in this functional unit consist of: i) signalling between the MS and the MSC; ii) signalling between the BSS and the MSC for access management. 3GPP
  • 67. Release 1999 9.2 67 3GPP TS 23.009 V3.14.0 (2003-06) Call control procedures MSC-A (functional unit 2) The call control procedures related to handover in MSC-A can be divided into two functional entities: - the first entity is the call control procedure as part of the normal interworking between the PSTN/ISDN and the PLMN; for an MS originating call MSC-A is the originating exchange, for an MS terminating call MSC-A is the destination exchange; - the second entity is the call control procedure for the connection between MSC-A and MSC-B in case of a handover from MSC-A to MSC-B. For this call control procedure the following applies. Call set-up - the connection to MSC-B is set up by procedures relevant to the signalling system used in the PSTN/ISDN to which MSC-A is connected. The call is set up by using the MS Handover Number received from MSC-B as part of the MAP procedure; - the call set-up direction will always be from MSC-A to MSC-B, even when the call was originally established by the MS. Functional unit 2 (see figure 2) should therefore keep information on call set-up direction in order to be able to interpret correctly any clearing signals (see below); - the unit should indicate the address complete condition to functional unit 3 and through-connect without awaiting the answer signal from MSC-B. This applies also to signalling systems where address complete signals are not supported. In such cases an artificial address complete is established by functional unit 2. Call clearing - call clearing consists of two parts: after inter-MSC handover, clearing of the MS-BSS connection and clearing of the inter-MSC connection. If a request to release the call is generated by the network while the MS is re-tuning from one BSS to another BSS, then MSC-A shall begin clearing the call to the network and queue the call release to the MS until the MS has resumed communication. This includes the case when MSC-B and/or MSC-B' are involved; - the MAP procedures are used to transfer information between MSC-B and MSC-A in order to maintain full call control within MSC-A. MSC-A determines, based on information received from MSC-B, the appropriate signals (according to 3GPP TS 24.008 [10]) to be sent to the MS, and sends this information to MSC-B; - when MSC-A clears the call to the MS it also clears the call control functions in MSC-B and sends the MAPSEND-END-SIGNAL response to release the MAP resources in MSC-B. The clearing of the connection is by procedures relevant to the signalling system in the PSTN/ISDN to which MSC-A is connected; - when the Signalling System no 7 ISDN User Part is used, the normal symmetric release procedures apply on both the connection to the fixed network and to MSC-B; - when a signalling system is used without a symmetric release possibility, some notice should be given to the clear-forward and clear-back procedures; - for MS terminating calls the following conditions apply on clear-forward and clear-back: - when a clear-forward signal is received on interface B' (see figure 1), MSC-A clears the circuit to MSC-B by normal clear-forward procedures; - when a clear-back signal is received from MSC-B, MSC-A starts normal clear-back procedures towards the fixed network (interface B') and sends the clear-forward signal on interface B'' in order to clear the connection with MSC-B. NOTE 1: This case corresponds to a fault situation. - for MS originated calls the following applies: - when MSC-A receives a clear-back signal from MSC-B, this signal must be interpreted as indicating a clearforward condition. MSC-A then clears both the connection on interface B' (see figure 1) and to MSC-B by normal clear-forward procedures. NOTE 2: This case corresponds to a fault situation. 3GPP
  • 68. Release 1999 - 68 3GPP TS 23.009 V3.14.0 (2003-06) when MSC-A receives a clear-back signal on interface B', MSC-A should distinguish between national and international connections: - for international connections where the Q.118 [1] supervision is done in the ISC, MSC-A sends a clearforward signal on both interface B' to the fixed network and interface B'' to MSC-B; - for national connections or for international connections where the Q.118 [1] supervision is not done in the ISC, a timer is started according to national practice for clear-back supervision and MSC-A proceeds as follows: i) if a clear-back signal is received from MSC-B, MSC-A interprets this as indicating a clear-forward condition and proceeds by clearing the connections on interface B' and to MSC-B by normal clearforward procedures; ii) if the timer expires, MSC-A proceeds by normal clear-forward of the connections on interface B' and to MSC-B. 9.3 Handover control procedures MSC-A (functional unit 3) The procedures of functional unit 3 are given in terms of SDL diagrams in figure 41. To easily distinguish the interface concerned the messages received or sent from this unit are prefixed with either 'MAP' for a MAP message, 'A' for an AInterface message or 'I' for an ISDN/PSTN message. The procedures of functional unit 3 include: i) initiation. The initiation condition is shown by the signal A-HANDOVER-REQUIRED. The diagram also includes queuing when there is no channel available. Calls for which handover has been initiated should be queued with priority higher than normal calls. They should have lower priority than emergency calls. ii) handover of calls within the area of MSC-A, i.e. handover case i). In this case MSC-A controls the procedures on both the previous and the new radio channel, using signals A-HANDOVER-REQUEST and A-HANDOVERCOMMAND. The handover procedure is completed when A-HANDOVER-COMPLETE is received. If this signal is not received (expiry of timer T102), the radio path and the connection on interface B' are released. In the case of ongoing GSM voice group calls for subsequent users of the VGCS channel uplink the original connection shall always be maintained. For handover devices with three-party capabilities the handover device is first set up so that all interfaces A', A'' and B' are connected (illustrated by the signal 'set up handover device'). This is done when the Handover Command is sent to the MS . The device is connected in its final position (i.e. A'' to B' for case ii)) (illustrated by the signal 'connect handover device') when A-HANDOVER-COMPLETE is received. iii) handover to MSC-B . This procedure is the one described in subclauses 7.1. and 7.2. For handover devices with three-party capabilities the handover device is set-up when MSC-A sends the Handover Command to the MS , i.e. the interfaces A', B' and B'' are then connected. The device is connected in its final position (i.e. B' to B'') when the successful procedure indication is received from functional unit 4. iv) subsequent handover to MSC-A . The procedure is described in subclauses 7.3. and 7.4. When a handover to MSC-A indication is received from functional unit 4, the handover device is set up so that interfaces B', B'' and A' are connected (for handover devices with three-party capabilities). When A-HANDOVER-COMPLETE is received, the device is connected in its final position (i.e. B' to A'). If A-HANDOVER-COMPLETE is not received (expiry of timer T104), the handover device releases interface A', B' and B''. 3GPP
  • 69. Release 1999 69 3GPP TS 23.009 V3.14.0 (2003-06) v) subsequent handover to a third MSC (MSC-B') . The procedure is described in subclauses 7.3. and 7.4. The handover device is set up in its initial position, (i.e. interconnection of interfaces B', B'' and B''') when the connection to MSC-B' has been established. MSC-B is informed via functional unit 4 that the connection has been established and that the procedure on the radio path can be initiated. The device is connected in its final position (i.e. B' to B''') when a successful procedure indication is received from functional unit 4. MSC-B is informed that all procedures in MSC-B can be terminated (illustrated by the MAP-SEND-END-SIGNAL response). The device returns to the state where B' and B'' are connected if the subsequent handover procedure fails. Timers in MSC-A. The procedures are supervised by timers in order to avoid a deadlock when responses are not received or the procedures fail. The following timers are defined: T101: this timer supervises the queuing time for a free channel. If T101 expires, a no channel indication is generated, a retry procedure could be applied as described in subclause 6.1. T101 is set by O&M, T102: this timer supervises the time for handover completion for handover between BSSs in MSC-A. T102 is set by O&M, T103: this timer supervises the time between issuing an A-HANDOVER-COMMAND from MSC-A and receiving a successful procedure indication from MSC-B. This timer also supervises the time between sending an A-HO-REQUEST-ACKNOWLEDGE to MSC-B and receiving a successful procedure indication from MSC-B'. If T103 expires, the handover procedure is terminated. T103 is set by O&M, T104: this timer supervises the time between sending of an A-HO-REQUEST-ACKNOWLEDGE to MSC-B and receiving the A-HANDOVER-COMPLETE from BSS-B on MSC-A. If the timer expires, the new radio channel is released. T104 is set by O&M. 9.4 MAP procedures in MSC-A (functional unit 4) The MAP procedures for handover are defined in 3GPP TS 29.002 [12]. They include: - procedures for basic handover; - procedures for subsequent handover. These procedures are as outlined in clause 7. 9.5 Interworking between Handover control procedures and MAP procedures in MSC-A The interworking between the Handover control procedures and the MAP procedures for handover is defined in 3GPP TS 29.010 [8]. It includes: - interworking at basic handover initiation; - interworking at subsequent handover completion. This interworking is not described in the present document. 9.6 Compatibility with GSM Phase 1 If the MSC-A initiates an Inter-MSC handover procedure according to Phase 2 MAP and BSSMAP protocols while using a Phase 1 BSSMAP protocol towards BSS-A, MSC-A has to perform the protocol interworking. The same holds if a Phase 2 BSSMAP protocol is used between MSC-A and BSS-A and the E-interface supports only Phase 1 protocol. 3GPP
  • 70. Release 1999 70 3GPP TS 23.009 V3.14.0 (2003-06) 10 Detailed procedures in MSC-B 10.1 BSS/MSC (MS/BSS) procedures MSC-B (functional unit 1) The handover procedures in this functional unit consist of: i) signalling between the MS and the MSC; ii) signalling between the BS and the MSC for access management. Signals exchanged with functional unit 3 are indicated in subclause 10.3. 10.2 Call control procedures MSC-B (functional unit 2) These procedures relate to the call control in MSC-B of the "handover" connection with MSC-A. For these procedures the following apply: Call set-up: - the connection is set up by MSC-A. MSC-B should provide, if possible, the following backward signals: - signals indicating unsuccessful call set-up and, if possible, the cause of call failure; - address complete signal; - answer signal (see note). NOTE: - The answer signal is not related to answering by the MS and it has no meaning in the handover procedure between MSC-A and MSC-B. But after successful handover or successful subsequent channel assignment using a circuit connection between MSC-A and MSC-B this signal is needed for bringing the connection in the answered state in the intermediate PSTN/ISDN exchanges. there will be no indication that the call applies to a handover. This information has to be derived from the MS Handover Number received during call set-up in relation to the earlier MAP-PREPARE-HANDOVER request/MAP-PREPARE-HANDOVER response procedure between MSC-A and MSC-B. Call clearing: - call clearing consists of two parts after inter-MSC handover: clearing of the BSS-MS connection and clearing of the inter-MSC connection, this case is only applicable to calls successfully handed over. If a request to release the call is generated by the network while the MS is re-tuning from one BSS to another BSS, then MSC-B shall begin clearing the call to the network and queue the call release to the MS until the MS has resumed communication; - the MAP is used to transfer information between MSC-A and MSC-B in order to make it possible for MSC-B to send the appropriate signals to the MS, specified in 3GPP TS 24.008 [10], and still leave the call control to MSC-A. MSC-A normally initiates release of the connection between MSC-A and MSC-B. Exceptionally MSC-B is allowed to release the connection if no MAP-SEND-END-SIGNAL response is received, or if the Handover is to be aborted. - when the Signalling System no 7 ISDN User Part is used, the normal symmetric release procedures apply. When a signalling system is used without a symmetric release possibility or a fault condition occurs, the following may apply: - when MSC-B receives a clear-forward signal from MSC-A, it shall release the radio resources; - in fault situation eg. machine malfunction or loss of the connection on interface A, MSC-B may send a clearback signal to MSC-A. 3GPP
  • 71. Release 1999 10.3 71 3GPP TS 23.009 V3.14.0 (2003-06) Handover control procedures MSC-B (functional unit 3) The procedures of functional unit 3 are given in form of SDL diagrams in figure 42. To easily distinguish the interface concerned the messages received or sent from this unit are prefixed with either 'MAP' for a MAP message, 'A' for an A-Interface message or 'I' for an ISDN/PSTN message. The procedure in functional unit 3 include: i) handover from MSC-A. This case is initiated by MSC-A, and includes allocation and establishment of the new radio channel. The procedure is outlined in subclauses 7.1. and 7.2. ii) intra-MSC handovers within the area controlled by MSC-B. This procedure is the same as that of i) in subclause 9.3, except that the A-HANDOVER-REQUIRED is received by MSC-B. After successful completion of the intra-MSC handover, MSC-B shall notify MSC-A by sending an A-HANDOVER-PERFORMED message. iii) subsequent handover to another MSC (MSC-A or MSC-B'). The initiation procedure is essentially the same as that of i) of subclause 9.3. The Handover Command to the MS is now generated by MSC-B after the A-HO-REQUEST-ACKNOWLEDGE is received from MSC-A (via functional unit 4). The procedure is terminated in MSC-B when MSC-B receives a terminate procedure indication from functional unit 4. Timers in MSC-B. The following procedures are supervised by timers in order to avoid a deadlock when responses are not received or the procedures fail. The following timers are defined: T201: this timer supervises the queuing time for a free channel. T201 is set by O&M; T202: this timer supervises the time for handover completion for handover between BSSs in MSC-B. If T202 expires, the radio path and the connection on interface B' are released. T202 is set by O&M; T204: this timer supervises the time between sending of address complete message to MSC-A and receiving the A-HANDOVER-COMPLETE from BSS-B on MSC-B. This timer also supervises the time between issuing the handover command to the MS and receiving the MAP-SEND-END-SIGNAL response from MSC-A, for a subsequent handover. In the case of a handover without circuit connection between MSC-A and MSC-B this timer supervises the time between issuing the A-HO-REQUEST-ACKNOWLEDGE to the MSC-A and receiving the A-HANDOVER-COMPLETE from BSS-B on MSC-B. If the timer expires, then any new radio channel is released. T204 is set by O&M; T210: this timer is used to supervise the time for establishing a circuit connection from MSC-A to MSC-B. When T210 expires, the allocated channel in MSC-B is released. T210 is set by O&M. This timer is not started when MSC-A explicitly indicates that no handover number is needed; T211: this timer is used to control the time between requesting a subsequent handover (A-HO-REQUEST to the MSC-A) and receiving the response from MSC-A (A-REQUEST-ACKNOWLEDGE/A-HO-FAILURE). If T211 expires, the existing connection with the MS is maintained. T211 is set by O&M. 10.4 MAP procedures MSC-B (functional unit 4) The MAP procedures for handover are defined in 3GPP TS 29.002 [12]. They include: - procedures for basic handover; - procedures for subsequent handover; - procedures for obtaining the handover number from the VLR. These procedures are outlined in clause 7. 3GPP
  • 72. Release 1999 10.5 72 3GPP TS 23.009 V3.14.0 (2003-06) Interworking between Handover control procedures and MAP procedures in MSC-B The interworking between the Handover control procedures and the MAP procedures for handover is defined in 3GPP TS 29.010 [8]. It includes: - interworking at basic handover completion; - interworking at subsequent handover initiation. This interworking is not described in the present document. 10.6 Compatibility with GSM Phase 1 If the MSC-B accepts an Inter-MSC handover procedure according to Phase 2 MAP and BSSMAP protocols while using a Phase 1 BSSMAP protocol towards BSS-B, MSC-B has to perform the protocol interworking. The same holds if a Phase 1 MAP protocol is requested on the E-interface and MSC-B uses a Phase 2 BSSMAP protocol towards BSS-B. 11 Detailed procedures in 3G_MSC-A For detailed procedures in MSC-A at handover within the GSM network, please see clause 9 "Detailed procedures in MSC-A". 11.1 RNC/BSC/3G_MSC and UE/MS/3G_MSC procedures in 3G_MSC-A (functional unit 1) The handover/relocation procedures in this functional unit consist of: i) signalling between the UE/MS and the 3G_MSC; ii) signalling between the RNS/BSS and the 3G_MSC for access management. 11.2 Call control procedures 3G_MSC-A (functional unit 2) The call control procedures related to handover/relocation in 3G_MSC-A can be divided into two functional entities: - - the first entity is the call control procedure as part of the normal interworking between the PSTN/ISDN and the PLMN/UTRAN; for an UE/MS originating call 3G_MSC-A is the originating exchange, for an UE/MS terminating call 3G_MSC-A is the destination exchange; the second entity is the call control procedure for the connection between 3G_MSC-A and 3G_MSC-B in case of a handover/relocation from 3G_MSC-A to 3G_MSC-B. For this call control procedure the following applies. Call set-up: - the connection to 3G_MSC-B is set up by procedures relevant to the signalling system used in the PSTN/ISDN to which 3G_MSC-A is connected. The call is set up by using the Handover Number received from 3G_MSC-B as part of the MAP procedure; - the call set-up direction will always be from 3G_MSC-A to 3G_MSC-B, even when the call was originally established by the UE/MS. Functional unit 2 (see figure 5) should therefore keep information on call set-up direction in order to be able to interpret correctly any clearing signals (see below); - the unit should indicate the address complete condition to functional unit 3 and through-connect without awaiting the answer signal from 3G_MSC-B. This applies also to signalling systems where address complete signals are not supported. In such cases an artificial address complete is established by functional unit 2. 3GPP
  • 73. Release 1999 73 3GPP TS 23.009 V3.14.0 (2003-06) Call clearing: - call clearing consists of two parts: after handover/relocation, clearing of the RNS-UE/MS or BSS-UE/MS connection and clearing of the inter-3G_MSC connection. If a request to release the call is generated by the network while the UE/MS is re-tuning from one RNS/BSS to another RNS/BSS, then 3G_MSC-A shall begin clearing the call to the network and queue the call release to the UE/MS until the UE/MS has resumed communication. This includes the case when 3G_MSC-B and/or 3G_MSC-B' are involved; - the MAP procedures are used to transfer information between 3G_MSC-B and 3G_MSC-A in order to maintain full call control within 3G_MSC-A. 3G_MSC-A determines, based on information received from 3G_MSC-B, the appropriate signals (according to 3GPP TS 24.008 [10]) to be sent to the UE/MS, and sends this information to 3G_MSC-B; - when 3G_MSC-A clears the call to the UE/MS it also clears the call control functions in 3G_MSC-B and sends the MAP-SEND-END-SIGNAL response to release the MAP resources in 3G_MSC-B. The clearing of the connection is by procedures relevant to the signalling system in the PSTN/ISDN to which 3G_MSC-A is connected; - when the Signalling System no 7 ISDN User Part is used, the normal symmetric release procedures apply on both the connection to the fixed network and to 3G_MSC-B; - when a signalling system is used without a symmetric release possibility, some notice should be given to the clear-forward and clear-back procedures; - for UE/MS terminating calls the following conditions apply on clear-forward and clear-back: - when a clear-forward signal is received on interface B' (see figure 4), 3G_MSC-A clears the circuit to 3G_MSC-B by normal clear-forward procedures; - when a clear-back signal is received from 3G_MSC-B, 3G_MSC-A starts normal clear-back procedures towards the fixed network (interface B') and sends the clear-forward signal on interface B'' in order to clear the connection with 3G_MSC-B. NOTE 1: This case corresponds to a fault situation. - for UE/MS originated calls the following applies: - when 3G_MSC-A receives a clear-back signal from 3G_MSC-B, this signal must be interpreted as indicating a clear-forward condition. 3G_MSC-A then clears both the connection on interface B' (see figure 4) and to 3G_MSC-B by normal clear-forward procedures; NOTE 2: This case corresponds to a fault situation. - when 3G_MSC-A receives a clear-back signal on interface B', 3G_MSC-A should distinguish between national and international connections: - for international connections where the Q.118 [1] supervision is done in the ISC, 3G_MSC-A sends a clear-forward signal on both interface B' to the fixed network and interface B'' to 3G_MSC-B; - for national connections or for international connections where the Q.118 [1] supervision is not done in the ISC, a timer is started according to national practice for clear-back supervision and MSC-A proceeds as follows: i) if a clear-back signal is received from 3G_MSC-B, 3G_MSC-A interprets this as indicating a clearforward condition and proceeds by clearing the connections on interface B' and to 3G_MSC-B by normal clear-forward procedures; ii) if the timer expires, 3G_MSC-A proceeds by normal clear-forward of the connections on interface B' and to 3G_MSC-B. 3GPP
  • 74. Release 1999 11.3 74 3GPP TS 23.009 V3.14.0 (2003-06) Handover/Relocation control procedures 3G_MSC-A (functional unit 3) The procedures of functional unit 3 are given in terms of SDL diagrams in figure 43. To easily distinguish the interface concerned the messages received or sent from this unit are prefixed with either 'MAP' for a MAP message, 'A' for an AInterface message, 'I' for an ISDN/PSTN message or 'Iu' for an Iu-message. The procedures of functional unit 3 include: i) initiation. The initiation condition is shown by the signal Iu-RELOCATION-REQUIRED or A-HANDOVERREQUIRED; The diagram also includes queuing when there is no channel available. Calls for which handover/relocation has been initiated should be queued with priority higher than normal calls. They should have lower priority than emergency calls. ii) handover/relocation of calls within the area of 3G_MSC-A, i.e. handover/relocation case i); In the handover/relocation from RNS-A/BSS-A to RNS-B/BSS-B 3G_MSC-A controls the procedures on both the previous and the new radio channel, using signals Iu-RELOCATION-REQUEST/A-HANDOVERREQUEST and Iu-RELOCATION-COMMAND/A-HANDOVER-COMMAND. The handover/relocation procedure is completed when Iu-RELOCATION-COMPLETE/A-HANDOVER-COMPLETE is received. If this signal is not received (expiry of timer T102, T302, T502 or T702), the radio path and the connection on interface B' are released. For handover/relocation devices with three-party capabilities the device is first set up so that all interfaces Iu'/A', Iu''/A'' and B' are connected (illustrated by the signal 'set up handover device'). This is done when the Relocation Command is sent to serving RNS or Handover Command is sent to the serving BSS. The device is connected in its final position (i.e. Iu''/ A'' to B' for case ii)) (illustrated by the signal 'connect handover device') when IuRELOCATION-COMPLETE/A-HANDOVER-COMPLETE is received. iii) relocation to 3G_MSC-B. This procedure is the one described in subclauses 8.3.1 and 8.3.2. For handover/relocation devices with three-party capabilities the device is set-up when 3G_MSC-A sends the Relocation Command to the UE, i.e. the interfaces Iu', B' and B'' are then connected. The device is connected in its final position (i.e. B' to B'') when the successful procedure indication is received from functional unit 4; iv) UMTS to GSM handover to MSC-B. This procedure is the one described in subclauses 8.1.1 and 8.1.2. For handover/relocation devices with three-party capabilities the device is set-up when 3G_MSC-A sends the Relocation Command to the serving RNS, i.e. the interfaces Iu', B' and B'' are then connected. The device is connected in its final position (i.e. B' to B'') when the successful procedure indication is received from functional unit 4; v) GSM to UMTS handover to 3G_MSC-B. This procedure is the one described in subclauses 8.2.1 and 8.2.2. For handover/relocation devices with three-party capabilities the device is set-up when MSC-A sends the Handover Command to the serving BSS , i.e. the interfaces A', B' and B'' are then connected. The device is connected in its final position (i.e. B' to B'') when the successful procedure indication is received from functional unit 4; vi) subsequent relocation from 3G_MSC-B to 3G_MSC-A. The procedure is described in subclauses 8.3.3.1 and 8.3.4.1. When a relocation to 3G_MSC-A indication is received from functional unit 4, the handover/relocation device is set up so that interfaces B', B'' and Iu' are connected (for devices with three-party capabilities). When Iu-RELOCATION-COMPLETE is received, the device is connected in its final position (i.e. B' to Iu'); If Iu-RELOCATION-COMPLETE is not received (expiry of timer T704), the handover/relocation device releases interface Iu', B' and B''. vii) subsequent GSM to UMTS handover from MSC-B to 3G_MSC-A. The procedure is described in subclauses 8.2.3.1 and 8.2.4.1. When a handover to 3G_MSC-A indication is received from functional unit 4, the handover device is set up so that interfaces B', B'' and A' are connected (for handover devices with three-party capabilities). When Iu-RELOCATION-COMPLETE is received, the device is connected in its final position (i.e. B' to Iu'); If Iu-RELOCATION-COMPLETE is not received (expiry of timer T504), the device releases interface Iu', B' and B''. 3GPP
  • 75. Release 1999 75 3GPP TS 23.009 V3.14.0 (2003-06) viii) subsequent UMTS to GSM handover from 3G_MSC-B to MSC-A. The procedure is described in subclauses 8.1.3.1 and 8.1.4.1. When a handover to MSC-A indication is received from functional unit 4, the handover device is set up so that interfaces B', B'' and Iu' are connected (for handover devices with three-party capabilities). When A-HANDOVER-COMPLETE is received, the device is connected in its final position (i.e. B' to A'); If A-HANDOVER-COMPLETE is not received (expiry of timer T304), the device releases interface A', B' and B''. ix) subsequent relocation from 3G_MSC-B to a third 3G_MSC (3G_MSC-B'). The procedure is described in subclauses 8.3.4.2 and 8.3.5.2. The handover/relocation device is set up in its initial position, (i.e. interconnection of interfaces B', B'' and B''') when the connection to 3G_MSC-B' has been established. 3G_MSC-B is informed via functional unit 4 that the connection has been established and that the procedure on the radio path can be initiated. The device is connected in its final position (i.e. B' to B''') when a successful procedure indication is received from functional unit 4. 3G_MSC-B is informed that all procedures in 3G_MSC-B can be terminated (illustrated by the MAP-SEND-END-SIGNAL response). The device returns to the state where B' and B'' are connected if the subsequent relocation procedure fails; x) subsequent UMTS to GSM handover from 3G_MSC-B to a third MSC (MSC-B'). The procedure is described in subclauses 8.1.3.2 and 8.1.4.2. The handover/relocation device is set up in its initial position, (i.e. interconnection of interfaces B', B'' and B''') when the connection to MSC-B' has been established. 3G_MSC-B is informed via functional unit 4 that the connection has been established and that the procedure on the radio path can be initiated. The device is connected in its final position (i.e. B' to B''') when a successful procedure indication is received from functional unit 4. 3G_MSC-B is informed that all procedures in 3G_MSC-B can be terminated (illustrated by the MAP-SEND-END-SIGNAL response). The device returns to the state where B' and B'' are connected if the subsequent UMTS to GSM handover procedure fails; xi) subsequent GSM to UMTS handover from MSC-B to a third MSC (3G_MSC-B'). The procedure is described in subclauses 8.2.3.2 and 8.2.4.2. The handover/relocation device is set up in its initial position, (i.e. interconnection of interfaces B', B'' and B''') when the connection to 3G_MSC-B' has been established. MSC-B is informed via functional unit 4 that the connection has been established and that the procedure on the radio path can be initiated. The device is connected in its final position (i.e. B' to B''') when a successful procedure indication is received from functional unit 4. MSC-B is informed that all procedures in MSC-B can be terminated (illustrated by the MAP-SEND-END-SIGNAL response). The device returns to the state where B' and B'' are connected if the subsequent GSM to UMTS handover procedure fails. Timers in 3G_MSC-A. The procedures are supervised by timers in order to avoid a deadlock when responses are not received or the procedures fail. The following timers are defined for SRNS Relocation: T701: this timer supervises the queuing time for a free channel for the relocation inside UMTS. If T701 expires, a no channel indication is generated and 3G_MSC-A will terminate the relocation as described in subclause 6.2.3. T701 is set by O&M; T702: this timer supervises the time for relocation completion for relocation between RNSs in 3G_MSC-A. T702 is set by O&M; T703: this timer supervises the time between issuing an Iu-RELOCATION-COMMAND from 3G_MSC-A and receiving a successful procedure indication from 3G_MSC-B. This timer also supervises the time between sending an IU-RELOCATION-REQUEST-ACKNOWLEDGE to 3G_MSC-B and receiving a successful procedure indication from 3G_MSC-B'. If T703 expires, the relocation procedure is terminated. T703 is set by O&M; T704: this timer supervises the time between sending of an IU-RELOCATION-REQUEST-ACKNOWLEDGE to 3G_MSC-B and receiving the Iu-RELOCATION-COMPLETE from RNS-B on 3G_MSC-A. If the timer expires, the new radio channel is released. T704 is set by O&M. 3GPP
  • 76. Release 1999 76 3GPP TS 23.009 V3.14.0 (2003-06) The following timers are defined for UMTS to GSM handover: T301: this timer supervises the queuing time for a free channel for the UMTS to GSM handover. If T301 expires, a no channel indication is generated and 3G_MSC-A will terminate the handover as described in subclause 6.2.3. T301 is set by O&M; T302: this timer supervises the time for UMTS to GSM handover completion for handover from RNS to BSS in 3G_MSC-A. T302 is set by O&M; T303: this timer supervises the time between issuing an Iu-RELOCATION-COMMAND from 3G_MSC-A and receiving a successful procedure indication from MSC-B. This timer also supervises the time between sending an A-HO-REQUEST-ACKNOWLEDGE to MSC-B and receiving a successful procedure indication from MSC-B'. If T303 expires, the UMTS to GSM handover procedure is terminated. T303 is set by O&M; T304: this timer supervises the time between sending of an A-HO-REQUEST-ACKNOWLEDGE to MSC-B and receiving the A-HANDOVER-COMPLETE from BSS-B on 3G_MSC-A. If the timer expires, the new radio channel is released. T304 is set by O&M. The following timers are defined for GSM to UMTS handover: T501: this timer supervises the queuing time for a free channel for the GSM to UMTS handover. If T501 expires, a no channel indication is generated and 3G_MSC-A will terminate the handover as described in subclause 6.2.3. T501 is set by O&M; T502: this timer supervises the time for GSM to UMTS handover completion for handover from BSS to RNS in 3G_MSC-A. T502 is set by O&M; T503: this timer supervises the time between issuing an A-HANDOVER-COMMAND from MSC-A and receiving a successful procedure indication from 3G_MSC-B. This timer also supervises the time between sending an A-HANDOVER-REQUEST-ACKNOWLEDGE to 3G_MSC-B and receiving a successful procedure indication from 3G_MSC-B'. If T503 expires, the GSM to UMTS handover procedure is terminated. T503 is set by O&M; T504: this timer supervises the time between sending of an A-HANDOVER-REQUEST-ACKNOWLEDGE to 3G_MSC-B and receiving the Iu-RELOCATION-COMPLETE from RNS-B on 3G_MSC-A. If the timer expires, the new radio channel is released. T504 is set by O&M. 11.4 MAP procedures in 3G_MSC-A (functional unit 4) The MAP procedures for handover/relocation are defined in 3GPP TS 29.002 [12]. They include: - procedures for basic handover/relocation; - procedures for subsequent handover/relocation. These procedures are as outlined in clause 8. 11.5 Interworking between Handover/Relocation control procedures and MAP procedures in 3G_MSC-A The interworking between the Handover/Relocation control procedures and the MAP procedures for handover/relocation is defined in 3GPP TS 29.010 [8]. It includes: - interworking at basic handover/relocation initiation; - interworking at subsequent handover/relocation completion. This interworking is not described in the present document. 3GPP
  • 77. Release 1999 11.6 77 3GPP TS 23.009 V3.14.0 (2003-06) Compatibility with GSM Phase 1 Interworking with the GSM Phase 1 is not supported. 11.7 Protocol interworking If the 3G_MSC-A initiates a basic inter-MSC UMTS to GSM handover procedure according to MAP and BSSMAP protocols while using a RANAP protocol towards RNS-A, 3G_MSC-A has to perform the protocol interworking between RANAP on the Iu-Interface and encapsulated BSSMAP on the E-interface. The same holds if 3G_MSC-A accepts a subsequent inter-3G_MSC GSM to UMTS handover back to 3G_MSC-A while using a RANAP protocol towards RNS-B. 12 Detailed procedures in 3G_MSC-B For detailed procedures in 3G_MSC-B at handover within the GSM network, please see clause 10 procedures in MSC-B'. 12.1 'Detailed RNC/BSC/3G_MSC (UE/MS/RNC/BSC) procedures in 3G_MSC-B (functional unit 1) The Intra and Inter-3G_MSC handover/relocation procedures in this functional unit consist of: i) signalling between the UE/MS and the 3G_MSC; ii) signalling between the RNS/BSS and the 3G_MSC for access management. Signals exchanged with functional unit 3 are indicated in subclause 12.3. 12.2 Call control procedures 3G_MSC-B (functional unit 2) These procedures relate to the call control in 3G_MSC-B of the "3G_MSC handover/relocation" connection with 3G_MSC-A. For these procedures the following apply: Call set-up: - the connection is set up by 3G_MSC-A. signals: 3G_MSC-B should provide, if possible, the following backward - signals indicating unsuccessful call set-up and, if possible, the cause of call failure; - address complete signal; - answer signal (see note). NOTE: - The answer signal is not related to answering by the UE/MS and it has no meaning in the 3G_MSC handover/relocation procedure between 3G_MSC-A and 3G_MSC-B. But after successful handover/relocation or successful subsequent channel assignment using a circuit connection between 3G_MSC-A and 3G_MSC-B this signal is needed for bringing the connection in the answered state in the intermediate PSTN/ISDN exchanges. there will be no indication that the call applies to a 3G_MSC handover/relocation. This information has to be derived from the UE/MS Handover Number received during call set-up in relation to the earlier MAPPREPARE-HANDOVER request/MAP-PREPARE-HANDOVER response procedure between 3G_MSC-A and 3G_MSC-B. 3GPP
  • 78. Release 1999 78 3GPP TS 23.009 V3.14.0 (2003-06) Call clearing: - call clearing consists of two parts after inter-3G_MSC handover/relocation: clearing of the RNS-UE/MS or the BSS-UE/MS connection and clearing of the inter-3G_MSC connection, these cases are only applicable to calls successfully handed over or relocated. If a request to release the call is generated by the network while the UE/MS is re-tuning from one RNS/BSS to another RNS/BSS, then 3G_MSC-B shall begin clearing the call to the network and queue the call release to the UE/MS until the UE/MS has resumed communication; - the MAP is used to transfer information between 3G_MSC-A and 3G_MSC-B in order to make it possible for 3G_MSC-B to send the appropriate signals to the UE/MS, specified in 3GPP TS 24.008 [10], and still leave the call control to 3G_MSC-A. 3G_MSC-A normally initiates release of the connection between 3G_MSC-A and 3G_MSC-B. Exceptionally 3G_MSC-B is allowed to release the connection if no MAP-SEND-END-SIGNAL response is received, or if the 3G_MSC Handover/Relocation is to be aborted; - when the Signalling System no 7 ISDN User Part is used, the normal symmetric release procedures apply. When a signalling system is used without a symmetric release possibility or a fault condition occurs, the following may apply: - when 3G_MSC-B receives a clear-forward signal from 3G_MSC-A, it shall release the radio resources; - in fault situation e.g. machine malfunction or loss of the connection on interface Iu or interface A, 3G_MSC-B may send a clear-back signal to 3G_MSC-A. 12.3 Handover/Relocation control procedures in 3G_MSC-B (functional unit 3) The procedures of functional unit 3 are given in form of SDL diagrams in figure 44. To easily distinguish the interface concerned the messages received or sent from this unit are prefixed with either 'MAP' for a MAP message, 'A' for an A-Interface message, 'Iu' for an Iu-Interface message or 'I' for an ISDN/PSTN message. The procedure in functional unit 3 include: i) inter 3G_MSC handover/relocation from 3G_MSC-A; This case is initiated by 3G_MSC-A, and includes allocation and establishment of the new radio resources. The procedure is outlined in subclauses 8.1.1 and 8.1.2. for UMTS to GSM handover, subclauses 8.2.1 and 8.2.2 for GSM to UMTS handover and subclauses 8.3.1 and 8.3.2 for relocation. ii) intra-3G_MSC UMTS to GSM handovers within the area controlled by 3G_MSC-B; This procedure is the same as that of ii) in subclause 11.3, except that the Iu-RELOCATION-REQUIRED is received by 3G_MSC-B. After successful completion of the intra-3G_MSC handover, 3G_MSC-B shall notify 3G_MSC-A by sending an A-HANDOVER-PERFORMED message. iii) intra-3G_MSC GSM to UMTS handovers within the area controlled by 3G_MSC-B; This procedure is the same as that of ii) in subclause 11.3, except that the A-HANDOVER-REQUIRED is received by 3G_MSC-B. After successful completion of the intra-3G_MSC handover, 3G_MSC-B shall notify 3G_MSC-A by sending an A-HANDOVER-PERFORMED message. iv) intra-3G_MSC SRNS Relocation within the area controlled by 3G_MSC-B; This procedure is the same as that of ii) in subclause 11.3, except that the Iu-RELOCATION-REQUIRED is received by 3G_MSC-B. After successful completion of the intra-3G_MSC SRNS relocation, if security algorithms have been changed, 3G_MSC-B shall notify 3G_MSC-A by sending an A-HANDOVERPERFORMED or an Iu-LOCATION-REPORT message, depending on the access network protocol used encapsulated on the E-interface (see subclauses 4.4.1 and 6.2.3). v) subsequent handover/relocation to another 3G_MSC (3G_MSC-A or 3G_MSC-B'); The initiation procedure is essentially the same as that of i) of subclause 11.3. The Handover Command to the BSS or the Relocation Command to the RNS is now generated by 3G_MSC-B after the A-HO-REQUESTACKNOWLEDGE or Iu-RELOCATION-REQUEST-ACKNOWLEDGE is received from 3G_MSC-A (via 3GPP
  • 79. Release 1999 79 3GPP TS 23.009 V3.14.0 (2003-06) functional unit 4). The procedure is terminated in 3G_MSC-B when 3G_MSC-B receives a terminate procedure indication from functional unit 4. Timers in 3G_MSC-B. The following procedures are supervised by timers in order to avoid a deadlock when responses are not received or the procedures fail. The following timers are defined for UMTS to GSM handover: T401: this timer supervises the queuing time for a free channel. T401 is set by O&M; T402: this timer supervises the time for handover completion for UMTS to GSM handover from RNS to BSS in 3G_MSC-B. If T402 expires, the radio path and the connection on interface B' are released. T402 is set by O&M; T404: this timer supervises the time between sending of address complete message to 3G_MSC-A and receiving the A-HANDOVER-COMPLETE from BSS-B on 3G_MSC-B. This timer also supervises the time between issuing the handover command to the UE/MS and receiving the MAP-SEND-END-SIGNAL response from 3G_MSC-A, for a subsequent handover from UMTS to GSM. In the case of a UMTS to GSM handover without circuit connection between 3G_MSC-A and 3G_MSC-B this timer supervises the time between issuing the A-HO-REQUEST-ACKNOWLEDGE to the 3G_MSC-A and receiving the AHANDOVER-COMPLETE from BSS-B on 3G_MSC-B. If the timer expires, then any new radio channel is released. T404 is set by O&M; T410: this timer is used to supervise the time for establishing a circuit connection from 3G_MSC-A to 3G_MSC-B. When T410 expires, the allocated channel in 3G_MSC-B is released. T410 is set by O&M. This timer is not started when 3G_MSC-A explicitly indicates that no handover number is needed; T411: this timer is used to control the time between requesting a subsequent UMTS to GSM handover (A-HO-REQUEST to the 3G_MSC-A) and receiving the response from 3G_MSC-A (A-HO-REQUESTACKNOWLEDGE/A-HO-FAILURE). If T411 expires, the existing connection with the UE/MS is maintained. T411 is set by O&M. The following timers are defined for GSM to UMTS handover: T601: this timer supervises the queuing time for a free radio resource. T601 is set by O&M; T602: this timer supervises the time for handover completion for GSM to UMTS handover from BSS to RNS in 3G_MSC-B. If T602 expires, the radio path and the connection on interface B' are released. T602 is set by O&M; T604: this timer supervises the time between sending of address complete message to 3G_MSC-A and receiving the Iu-RELOCATION-COMPLETE from RNS-B on 3G_MSC-B. This timer also supervises the time between issuing the handover command to the UE/MS and receiving the MAP-SEND-END-SIGNAL response from 3G_MSC-A, for a subsequent handover from GSM to UMTS. In the case of a GSM to UMTS handover without circuit connection between 3G_MSC-A and 3G_MSC-B this timer supervises the time between issuing the A-HO-REQUEST-ACKNOWLEDGE to the 3G_MSC-A and receiving the IuRELOCATION-COMPLETE from RNS-B on 3G_MSC-B. If the timer expires, then any new radio resource is released. T604 is set by O&M; T610: this timer is used to supervise the time for establishing a circuit connection from 3G_MSC-A to 3G_MSC-B. When T610 expires, the allocated radio resource in 3G_MSC-B is released. T610 is set by O&M. This timer is not started when 3G_MSC-A explicitly indicates that no handover number is needed; T611: this timer is used to control the time between requesting a subsequent GSM to UMTS handover (A-HO-REQUEST to the 3G_MSC-A) and receiving the response from 3G_MSC-A (A-HO-REQUESTACKNOWLEDGE/A-HO-FAILURE). If T611 expires, the existing connection with the UE/MS is maintained. T611 is set by O&M. The following timers are defined for SRNS Relocation: T801: this timer supervises the queuing time for a free radio resource. T801 is set by O&M; 3GPP
  • 80. Release 1999 80 3GPP TS 23.009 V3.14.0 (2003-06) T802: this timer supervises the time for relocation completion for relocation between RNSs in 3G_MSC-B. If T802 expires, the radio path and the connection on interface B' are released. T802 is set by O&M; T804: this timer supervises the time between sending of address complete message to 3G_MSC-A and receiving the Iu-RELOCATION-COMPLETE from RNS-B on 3G_MSC-B. This timer also supervises the time between issuing the handover command to the UE and receiving the MAP-SEND-END-SIGNAL response from 3G_MSC-A, for a subsequent relocation. In the case of a relocation without circuit connection between 3G_MSC-A and 3G_MSC-B this timer supervises the time between issuing the Iu-RELOCATION-REQUEST-ACKNOWLEDGE to the 3G_MSC-A and receiving the Iu-RELOCATION-COMPLETE from RNS-B on 3G_MSC-B. If the timer expires, then any new radio resource is released. T804 is set by O&M; T810: this timer is used to supervise the time for establishing a circuit connection from 3G_MSC-A to 3G_MSC-B. When T810 expires, the allocated channel in 3G_MSC-B is released. T810 is set by O&M. This timer is not started when 3G_MSC-A explicitly indicates that no handover number is needed; T811: this timer is used to control the time between requesting a subsequent relocation (Iu-RELOCATIONREQUEST to the 3G_MSC-A) and receiving the response from 3G_MSC-A (Iu-RELOCATIONREQUEST-ACKNOWLEDGE/ Iu-RELOCATION-FAILURE). If T811 expires, the existing connection with the UE is maintained. T811 is set by O&M. 12.4 MAP procedures in 3G_MSC-B (functional unit 4) The MAP procedures for handover/relocation are defined in 3GPP TS 29.002 [12]. They include: - procedures for basic handover/relocation; - procedures for subsequent handover/relocation; - procedures for obtaining the handover number from the VLR. These procedures are outlined in clause 8. 12.5 Interworking between Handover/Relocation control procedures and MAP procedures in 3G_MSC-B The interworking between the Handover/Relocation control procedures and the MAP procedures for handover/relocation is defined in 3GPP TS 29.010 [8]. It includes: - interworking at basic handover/relocation completion; - interworking at subsequent handover/relocation initiation. This interworking is not described in the present document. 12.6 Compatibility with GSM Phase 1 GSM phase 1 is not supported. 12.7 Protocol interworking If the 3G_MSC-B accepts an Inter-3G_MSC GSM to UMTS handover procedure according to MAP and BSSMAP protocols while using a RANAP protocol towards RNS-B, 3G_MSC-B has to perform the protocol interworking between RANAP on the Iu-Interface and encapsulated BSSMAP on the E-interface. The same holds if 3G_MSC-B initiates a subsequent inter-MSC UMTS to GSM handover while using a RANAP protocol towards RNS-A. 3GPP
  • 81. Release 1999 81 3GPP TS 23.009 V3.14.0 (2003-06) If during the supervision, i.e. while the UE/MS is not in the area of MSC-A or 3G_MSC-A, the protocol used encapsulated on the E-interface and the protocol used between 3G_MSC-B and the serving BSS or RNS are different, then 3G_MSC-B has to perform the protocol interworking between BSSAP and RANAP. NOTE: The two protocols are different, e.g., after an inter-MSC GSM to UMTS inter-system handover, or after an inter-MSC SRNS relocation to 3G_MSC-B followed by a subsequent intra-3G_MSC-B UMTS to GSM inter-system handover. 13 Subsequent channel assignment using a circuit connection between MSC-A and MSC-B 13.1 GSM handover If a circuit connection has to be set up (for example for a Mobile Originated or Mobile Terminated Call Establishment) after an Inter-MSC handover without circuit connection, MSC-A shall request a Handover Number using a MAP-PREPARE-HANDOVER request, containing the A-ASSIGNMENT-REQUEST, on the established MAP connection. If MSC-B indicates to MSC-B and to MSC-A that at least one of two procedures assignment or Handover Number allocation can not be completed, then MSC-A shall terminate the circuit establishment attempt. The existing connection to the MS shall be maintained, if possible. Upon receipt of the MAP-PREPARE-HANDOVER request MSC-B shall perform the requested assignment operation towards the BSS. In addition it shall retrieve a Handover Number from VLR-B. If a failure occurs in the assignment or Handover Number allocation then it shall be reflected in the MAP-PREPARE-HANDOVER response that at least one of these two procedures has not been completed (i.e. either by a MAP-PREPARE-HANDOVER result with the assignment procedure outcome and the Handover Number allocation outcome or by a MAP-PREPARE-HANDOVER error). When MSC-A receives a successful MAP-PREPARE-HANDOVER response it shall establish a circuit connection to MSC-B by using the appropriate network supported procedures. In figure 36 this is indicated by the IAM (Initial Address Message) and ACM (Address Complete Message). MSC-B shall also send the Answer message if appropriate to the signalling system. Upon receipt of the Answer MSC-A shall consider the circuit connection establishment phase complete. If a failure occurs during the cirucit establishment phase then the existing connection to the MS shall be maintained, if possible. 3GPP
  • 82. Release 1999 82 3GPP TS 23.009 V3.14.0 (2003-06) BSS-B/MS MSC-A MSC-B MAP-Prepare-Handover req. VLR-B MAP-Alloc-Handover-Number req. A-ASG-REQUEST A-ASG-COMPLETE MAP-Prep-Handover resp. MAP-Send-Handover-Report req. IAM MAP-Send-Handover-Report resp. (1) ACM Answer End of call RELEASE MAP-Send-End-Signal resp. NOTE 1: Can be sent at any time after the reception of IAM. Figure 36: Successful circuit-switched call establishment after a Basic Handover without circuit connection 13.2 UMTS to GSM handover If a circuit connection has to be set up (for example for a Mobile Originated or Mobile Terminated Call Establishment) after an Inter-3G_MSC UMTS to GSM handover without circuit connection, 3G_MSC-A shall request a Handover Number using a MAP-PREPARE-HANDOVER request, containing the A-ASSIGNMENT-REQUEST, on the established MAP connection. If MSC-B indicates to MSC-B and to 3G_MSC-A that at least one of two procedures assignment or Handover Number allocation can not be completed, then 3G_MSC-A shall terminate the circuit establishment attempt. The existing connection to the UE/MS shall be maintained, if possible. Upon receipt of the MAP-PREPARE-HANDOVER request MSC-B shall perform the requested assignment operation towards the BSS. In addition it shall retrieve a Handover Number from VLR-B. If a failure occurs in the assignment or Handover Number allocation then it shall be reflected in the MAP-PREPARE-HANDOVER response that at least one of these two procedures has not been completed (i.e. either by a MAP-PREPARE-HANDOVER result with the assignment procedure outcome and the Handover Number allocation outcome or by a MAP-PREPARE-HANDOVER error). When 3G_MSC-A receives a successful MAP-PREPARE-HANDOVER response, it shall establish a circuit connection to MSC-B by using the appropriate network supported procedures. In figure 37 this is indicated by the IAM (Initial Address Message) and ACM (Address Complete Message). MSC-B shall also send the Answer message if appropriate to the signalling system. Upon receipt of the Answer 3G_MSC-A shall consider the circuit connection establishment phase complete. If a failure occurs during the circuit establishment phase then the existing connection to the UE/MS shall be maintained, if possible. 3GPP
  • 83. Release 1999 83 3GPP TS 23.009 V3.14.0 (2003-06) BSS-B/UE/MS 3G MSC-A MSC-B MAP-Prepare-Handover req. VLR-B MAP-Alloc-Handover-Number req. A-ASG-REQUEST A-ASG-COMPLETE MAP-Prep-Handover resp. MAP-Send-Handover-Report req. IAM MAP-Send-Handover-Report resp. (1) ACM Answer End of call RELEASE MAP-Send-End-Signal resp. NOTE 1: Can be sent at any time after the reception of IAM. Figure 37: Successful circuit-switched call establishment after a Basic UMTS to GSM Handover without circuit connection 13.3 GSM to UMTS handover If a circuit connection has to be set up (for example for a Mobile Originated or Mobile Terminated Call Establishment) after an Inter-3G_MSC GSM to UMTS handover without circuit connection, MSC-A shall request a Handover Number using a MAP-PREPARE-HANDOVER request, containing the A-ASSIGNMENT-REQUEST, on the established MAP connection. If 3G_MSC-B indicates to 3G_MSC-B and to MSC-A that at least one of two procedures assignment or Handover Number allocation can not be completed, then MSC-A shall terminate the circuit establishment attempt. The existing connection to the UE/MS shall be maintained, if possible. Upon receipt of the MAP-PREPARE-HANDOVER request 3G_MSC-B shall perform the requested assignment operation towards the RNS. In addition it shall retrieve a Handover Number from VLR-B. If a failure occurs in the assignment or Handover Number allocation then it shall be reflected in the MAP-PREPARE-HANDOVER response that at least one of these two procedures has not been completed (i.e. either by a MAP-PREPARE-HANDOVER result with the assignment procedure outcome and the Handover Number allocation outcome or by a MAP-PREPAREHANDOVER error). 3G_MSC-B inserts the transcoder according to the information received from MSC-A. When MSC-A receives a successful MAP-PREPARE-HANDOVER response, it shall establish a circuit connection to 3G_MSC-B by using the appropriate network supported procedures. In figure 38 this is indicated by the IAM (Initial Address Message) and ACM (Address Complete Message). 3G_MSC-B shall also send the Answer message if appropriate to the signalling system. Upon receipt of the Answer MSC-A shall consider the circuit connection establishment phase complete. If a failure occurs during the circuit establishment phase then the existing connection to the UE/MS shall be maintained, if possible. 3GPP
  • 84. Release 1999 84 3GPP TS 23.009 V3.14.0 (2003-06) RNS-B/UE/MS MSC-A 3G_MSC-B MAP-Prepare-Handover req. VLR-B MAP-Alloc-Handover-Number req. IU-RAB-ASG-REQUEST IU-RAB-ASG-COMPLETE MAP-Prep-Handover resp. MAP-Send-Handover-Report req. IAM MAP-Send-Handover-Report resp. (1) ACM Answer End of call RELEASE MAP-Send-End-Signal resp. NOTE 1: Can be sent at any time after the reception of IAM. Figure 38: Successful circuit-switched call establishment after a Basic GSM to UMTS Handover without circuit connection 13.4 SRNS Relocation 13.4.1 Without circuit connection If a circuit connection has to be set up (for example for a Mobile Originated or Mobile Terminated Call Establishment) after an Inter-3G_MSC relocation without circuit connection, 3G_MSC-A shall request a Handover Number using a MAP-PREPARE-HANDOVER request, containing the IU-RAB-ASSIGNMENT-REQUEST, on the established MAP connection. If 3G_MSC-B indicates to 3G_MSC-B and to 3G_MSC-A that at least one of two procedures (RAB) assignment or Handover Number allocation can not be completed, then 3G_MSC-A shall terminate the circuit establishment attempt. The existing connection to the UE shall be maintained, if possible. Upon receipt of the MAP-PREPARE-HANDOVER request, 3G_MSC-B shall perform the requested RAB assignment operation towards the RNS. In addition it shall retrieve a Handover Number from VLR-B. and connect a transcoder in case of TDM networks. If a failure occurs in the RAB assignment or Handover Number allocation then it shall be reflected in the MAP-PREPARE-HANDOVER response that at least one of these two procedures has not been completed (i.e. either by a MAP-PREPARE-HANDOVER result with the RAB assignment procedure outcome and the Handover Number allocation outcome or by a MAP-PREPARE-HANDOVER error). When 3G_MSC-A receives a successful MAP-PREPARE-HANDOVER response, it shall establish a circuit connection to 3G_MSC-B by using the appropriate network supported procedures. In figure 39 this is indicated by the IAM (Initial Address Message) and ACM (Address Complete Message). 3G_MSC-B shall also send the Answer message if appropriate to the signalling system. Upon receipt of the Answer 3G_MSC-A shall consider the circuit connection establishment phase complete. If a failure occurs during the circuit establishment phase then the existing connection to the UE shall be maintained, if possible. 13.4.2 With circuit connection (Optional functionality) If 3G_MSC-A and 3G_MSC-B support the optional supplementary service Multicall (See 3GPP TS 23.135), 3G_MSCA and 3G_MSC-B shall have the following functionality additionally to the description in section 13.4.1. 3GPP
  • 85. Release 1999 85 3GPP TS 23.009 V3.14.0 (2003-06) A new circuit connection shall be able to set up (for example for a new Mobile Originated or a new Mobile Terminated Call Establishment) after an Inter-3G_MSC relocation with one or several circuit connections. The procedures for the establishment of the additional circuit connection in 3G_MSC-A and 3G_MSC-B are the same as that described in section 13.4.1. RNS-B/UE 3G_MSC-A 3G_MSC-B MAP-Prepare-Handover req. VLR-B MAP-Alloc-Handover-Number req. IU-RAB-ASG-REQUEST IU-RAB-ASG-COMPLETE MAP-Prep-Handover resp. MAP-Send-Handover-Report req. IAM MAP-Send-Handover-Report resp. (1) ACM Answer End of call RELEASE MAP-Send-End-Signal resp. NOTE 1: Can be sent at any time after the reception of IAM. Figure 39: Successful circuit-switched call establishment after a Basic Relocation without circuit connection 14 Directed retry handover Editor's Note: 14.1 [Directed retry in the cases of SRNS relocation is FFS] GSM handover The directed retry procedure allows the network to select the optimum cell for the Mobile Station. The process of directed retry involves the assignment of a Mobile Station to a radio channel on a cell other than the serving cell. This process is triggered by the assignment procedures, as described in 3GPP TS 08.08 [5], and employs internal or external handover procedures as described in clauses 6 and 7. The successful procedure for a directed retry is as shown in figure 40 and as described below. If during the assignment phase, as represented by the A-ASSIGNMENT-REQUEST message, a handover becomes necessary, due to either radio conditions or congestion, then the Mobile Station may be handed over to a different cell. When the decision has been made to handover the MS the BSS-A may send an A-ASSIGNMENT-FAILURE message, indicating 'directed retry', before sending the A-HANDOVER-REQUIRED message to MSC-A, indicating 'directed retry'. However BSS-A may alternatively send the A-HANDOVER-REQUIRED message, indicating 'directed retry', without sending the A-ASSIGNMENT-FAILURE message. Other cause values may be used instead of "Directed Retry" in the A-HANDOVER-REQUIRED message, this will allow the MSC to take different actions dependent on the received cause. Upon receipt of the A-HANDOVER-REQUIRED message from BSS-A, then MSC-A shall initiate the handover as described in clauses 6 and 7. No resources shall be cleared in the MSC-A or BSS-A for this connection. After receipt of the A-HANDOVER-COMPLETE message from BSS-B the assignment procedure shall be considered to be complete and the resources on BSS-A shall be cleared. 3GPP
  • 86. Release 1999 86 3GPP TS 23.009 V3.14.0 (2003-06) MS MS BSS-A MSC-A BSS-B A-Assignment-Request A-Assignment-Failure A-Handover-Required A-Handover-Request A-Handover-Request-Ack A-Handover-Command RI-HO-Command RI-HO-Access A-Handover-Detect RI-HO-Complete A-Handover-Complete A-Clear-Command A-Clear-Complete Figure 40: Example of a Directed Retry Intra-MSC Handover Procedure If a failure occurs during the handover attempt, for example A-HANDOVER-FAILURE returned from BSS-A or BSSB, then MSC-A will terminate the handover to BSS-B. Under these conditions MSC-A may optionally take one of a number of actions: i) retry the handover to the same cell; ii) select the next cell from the list contained in the A-HANDOVER-REQUIRED message and attempt a handover to the new cell; iii) send an A-HANDOVER-REQUIRED-REJECT to BSS-A, if an A-HANDOVER-COMMAND has not already been sent; iv) retry the assignment procedure to BSS-A, if the failure message was returned from BSS-A. This option is additional to those for normal handover; v) Clear the complete call. The procedures for Inter-MSC handover are also applicable to the directed retry process. If an Inter-MSC handover is necessary then the assignment process should be considered to have completed successfully upon receipt of the A-HOCOMPLETE included in the MAP-SEND-END-SIGNAL request. 14.2 GSM to UMTS handover The directed retry procedure allows the network to select the optimum cell for the UE/MS. The process of directed retry involves the assignment of a UE/MS to a radio channel on a cell other than the serving cell. This process is triggered by the assignment procedures, as described in 3GPP TS 08.08 [5], and employs internal or external GSM to UMTS handover procedures as described in clauses 6.2.2 and 8.2. The successful procedure for a directed retry in case of an intra-3G_MSC GSM to UMTS handover is as shown in figure 40a and as described below. If during the assignment phase, as represented by the A-ASSIGNMENT-REQUEST message, a GSM to UMTS handover becomes necessary, due to either radio conditions or congestion, then the UE/MS may be handed over to a UMTS cell. When the decision has been made to handover the UE/MS the BSS-A may send an A-ASSIGNMENTFAILURE message, indicating 'directed retry', before sending the A-HANDOVER-REQUIRED message to 3G_MSC-A, indicating 'directed retry'. However BSS-A may alternatively send the A-HANDOVER-REQUIRED message, indicating 'directed retry', without sending the A-ASSIGNMENT-FAILURE message. Other cause values may be used instead of "Directed Retry" in the A-HANDOVER-REQUIRED message, this will allow the 3G_MSC to 3GPP
  • 87. Release 1999 87 3GPP TS 23.009 V3.14.0 (2003-06) take different actions dependent on the received cause. Upon receipt of the A-HANDOVER-REQUIRED message from BSS-A, then 3G_MSC-A shall initiate the GSM to UMTS handover as described in clauses 6.2.2 and 8.2. No resources shall be cleared in the 3G_MSC-A or BSS-A for this connection. After receipt of the Iu-RELOCATION-COMPLETE message from RNS-B the assignment procedure shall be considered to be complete and the resources on BSS-A shall be cleared. UE/MS UE/MS BSS-A 3G_MSC-A RNS-B A-Assignment-Request A-Assignment-Failure A-Handover-Required Iu-Relocation-Request Iu-Relocation-Request-Ack A-Handover-Command RI-HO-Command Iu-Relocation-Detect RRC-HO-Complete Iu-Relocation-Complete A-Clear-Command A-Clear-Complete Figure 40a: Example of a Directed Retry Intra-3G_MSC GSM to UMTS Handover Procedure If a failure occurs during the handover attempt, for example A-HANDOVER-FAILURE returned from BSS-A or IuRELOCATION FAILURE from RNS-B then 3G_MSC-A will terminate the GSM to UMTS handover to RNS-B. Under these conditions 3G_MSC-A may optionally take one of a number of actions: i) send an A-HANDOVER-REQUIRED-REJECT to BSS-A, if an A-HANDOVER-COMMAND has not already been sent; ii) retry the assignment procedure to BSS-A, if the failure message was returned from BSS-A. This option is additional to those for normal handover; iii) Clear the complete call. The procedures for Inter-3G_MSC GSM to UMTS handover are also applicable to the directed retry process. If an Inter-3G_MSC GSM to UMTS handover is necessary then the assignment process should be considered to have completed successfully upon receipt of the A-HO-COMPLETE included in the MAP-SEND-END-SIGNAL request. 14.3 UMTS to GSM handover The directed retry procedure allows the network to select the optimum cell for the UE/MS. The process of directed retry involves the assignment of a UE/MS to a radio channel on a cell other than the serving cell. This process is triggered by the assignment procedures, as described in 3GPP TS 25.413 [1], and employs UMTS to GSM handover procedures as described in clauses 6.2.1 and 8.1. The successful procedure for a directed retry in case of an intra-3G_MSC UMTS to GSM handover is as shown in figure 40b and as described below. If during the assignment phase, as represented by the Iu-RAB-ASSIGNMENT-REQUEST message, a UMTS to GSM handover becomes necessary, due to either radio conditions or congestion, then the UE/MS may be handed over to a GSM cell. When the decision has been made to handover the UE/MS the RNS-A shall send an Iu-RABASSIGNMENT-RESPONSE message, indicating 'directed retry', before sending the Iu-RELOCATION-REQUIRED message to 3G_MSC-A, indicating 'directed retry'. Other cause values may be used instead of "Directed Retry" in the 3GPP
  • 88. Release 1999 88 3GPP TS 23.009 V3.14.0 (2003-06) Iu-RELOCATION-REQUIRED message, this will allow the 3G_MSC to take different actions dependent on the received cause. Upon receipt of the Iu-RELOCATION-REQUIRED message from RNS-A, then 3G_MSC-A shall initiate the UMTS to GSM handover as described in clauses 6.2.1 and 8.1. No resources shall be cleared in the 3G_MSC-A or RNS-A for this connection. After receipt of the A-HANDOVER-COMPLETE message from BSS-B the assignment procedure shall be considered to be complete and the resources on RNS-A shall be cleared. UE/MS UE/MS RNS-A 3G_MSC-A BSS-B Iu- RAB-Assignment-Request Iu- RAB-Assignment-Response Iu-Relocation-Required A-Handover-Request A-Handover-Request-Ack Iu-Relocation-Command RRC-HO-Command RI-HO-Access A-Handover-Detect RI-HO-Complete A-Handover-Complete Iu-Release-Command Iu-Release-Complete Figure 40b: Example of a Directed Retry Intra-3G_MSC UMTS to GSM Handover Procedure If a failure occurs during the handover attempt, for example Iu-RELOCATION FAILURE returned from RNS-A or AHANDOVER-FAILURE from BSS-B then 3G_MSC-A will terminate the UMTS to GSM handover to BSS-B. Under these conditions 3G_MSC-A may optionally take one of a number of actions: i) send an Iu-RELOCATION-PREPARATION FAILURE to RNS-A, if an Iu-RELOCATION-COMMAND has not already been sent; ii) retry the assignment procedure to RNS-A, if the failure message was returned from RNS-A. This option is additional to those for normal handover; iii) Clear the complete call. The procedures for Inter-3G_MSC UMTS to GSM handover are also applicable to the directed retry process. If an Inter-3G_MSC UMTS to GSM handover is necessary then the assignment process should be considered to have completed successfully upon receipt of the A-HO-COMPLETE included in the MAP-SEND-END-SIGNAL request. 15 SDL diagrams NOTE 1: The message primitive names used in the SDL diagrams and message flows in the present document do not represent the actual messages specified in the GSM or 3GPP stage 3 technical specifications. The primitive names are only intended to be indicative of their use in the present document. SDL Annotation. The following conventions and abbreviations have been used in the SDLs. Text included in '[]' is used to indicate either, the BSSMAP message (as defined in 3GPP TS 09.08 [7]) included in the message, or the transport of a Handover Number. When traversing the following SDLs it may be possible that resources appear to be released repeatedly, however these operations are only executed once on their first occurrence. Furthermore it maybe that certain messages cannot, in practice, be received in particular states, after specific events have taken place. In general both of the above cases are 3GPP
  • 89. Release 1999 89 3GPP TS 23.009 V3.14.0 (2003-06) obvious. This approach has been adopted (in line with other GSM Technical Specifications) in order to reduce the complexity of the SDLs and improve clarity, without reducing the quality of the functional description. The following abbreviations have been used in the SDLs: A-HO-REQUEST A-HANDOVER-REQUEST A-HO-REQUEST-ACK A-HANDOVER-REQUEST-ACK. A-HO-COMPLETE A-HANDOVER-COMPLETE A-HO-DETECT A-HANDOVER-DETECT A-HO-PERFORMED A-HANDOVER-PERFORMED A-ASG-REQUEST A-ASSIGNMENT-REQUEST A-ASG-COMPLETE A-ASSIGNMENT-COMPLETE A-ASG-FAILURE A-ASSIGNMENT-FAILURE MAP-PAS req MAP-PROCESS-ACCESS-SIGNALLING req. MAP-FAS req MAP-FORWARD-ACCESS-SIGNALLING req. IU-RLC-REQUEST IU-RELOCATION-REQUEST IU-RLC-REQUEST-ACK IU-RELOCATION-REQUEST-ACK IU-RLC-COMPLETE IU-RELOCATION-COMPLETE IU-RLC-DETECT IU-RELOCATION-DETECT IU-IREL-REQUEST IU-IU-RELEASE-REQUEST IU-RREL-REQUEST IU-RAB-RELEASE-REQUEST IU-RASG-REQUEST IU-RAB-ASSIGNMENT-REQUEST IU-RASG-RESPONSE IU-RAB-ASSIGNMENT-RESPONSE NOTE 2: The SDL diagrams have been checked for consistency with the allocation of the A interface circuits by the BSC. The conclusion was that SDLs are expressed in general terms, and offer a sufficient latitude of interpretation to be consistent with the allocation of A interface circuits by the BSC. 3GPP
  • 90. Release 1999 90 3GPP TS 23.009 V3.14.0 (2003-06) Pro ce d u re M S C _ A_ H O S he e t1 (2 6) Proc edur e for H a ndo ve r in M S C -A IDLE C al l i n P rogre s s on MS C -A A-H AN DO VE R- R EQ UIR E D from B SS -A 1 Known M S C? Fr om M S or N etwo r k Im plicit R el eas e of BS S- A C all Re lease Yes No No H and over al low ed to C ell ? Ye s W hic h M SC ? M S C -B M S C- A K now n B SS ? No Ye s Yes 3 Select N ew Cel l? R esour ces on B SS - B ? No Ye s No No Send R ejec t? Yes A-H AN D OVE R R EJ EC T to BS S - A C al l i n P rogre s s on MS C -A 2 4 ID LE Figure 41 (Sheet 1 of 26): Handover control procedure in MSC-A 3GPP
  • 91. Release 1999 91 3GPP TS 23.009 V3.14.0 (2003-06) Pro ce d u re M S C _ A_ H O S he e t2 (2 6) H ando ver on M SC - A from B S S -A to B S S- B . Proc edur e for H a ndo ve r in M S C -A 2 A -H AN DO VE R -R E QU E ST to B S S- B S et T101 W ait for C hannel A ll ocation Intra- MSC A -H AN D OVE R R EQU E S T- ACK from BS S -B A - H AN D OV E R F AILU R E fr om B S S- B Fr o m M S or Netwo rk E xpiry T 101 R eset T101 A - CLEA R -R EQU ES T fr om BS S - A R eset T 101 Q ueue M es sa ges for M S in M S C -A Cal l Rel eas e C all R elease to Netw ork Canc el Chan nel H an dov er C om mand in BS S -B to M S via B S S -A S et U p H andov er D evice S et T102 Interna l m ess age in M SC -A Retr y Hand over Attem pt? Yes No R el ease Res ources in B S S-A N ew C ell Can c el C hannel in B S S-B Cell ? Sa m e C e ll W ait for a cc es s by MS o n B SS 2 1 3 Figure 41 (Sheet 2 of 26): Handover control procedure in MSC-A 3GPP IDLE
  • 92. Release 1999 92 3GPP TS 23.009 V3.14.0 (2003-06) Procedure MSC_A_H O Sheet3 (26) Proc edure for Hando ve r in MSC-A Wait for access by MS on B SS A-HANDOVERDETECT from BSS-B A-HANDOVERCOMPLETE from BS S-B Connect the Handover Device (O ption) O nly if not already c on nec ted Connec t the Handov er Device (Option) Reset T102 Relea se Res ources in BSS-A Forward queued mes sages for MS via BSS-B W ait for acc es s by MS on BSS Call in Progress on MSC-A Figure 41 (Sheet 3 of 26): Handover control procedure in MSC-A 3GPP
  • 93. Release 1999 93 3GPP TS 23.009 V3.14.0 (2003-06) Procedure Sheet4(26) Procedure for Handover in MSC-A Wait for access by MS on BSS A-HANDOVERFAILURE from BSS-A Reset T102 Forward queued messages for MS via BSS-A A-CLEARREQUEST from BSS-A A-CLEARREQUEST from BSS-B (Allowed once in this state) Release Resources in BSS-B (Allowed once in this state) Expiry T102 Call Release From Network Release Resources Release Resources in BSS-A in BSS-A Yes Wait for MS on BSS-B? No Release Handover Device Reset T102 Release Resources in BSS-B Release Handover Device Release Resources in BSS-B Call Release to Network Release Handover Device Call in Progress on MSC-A Wait for access by MS on BSS IDLE Wait for access by MS on BSS Figure 41 (Sheet 4 of 26): Handover control procedure in MSC-A 3GPP
  • 94. Release 1999 94 3GPP TS 23.009 V3.14.0 (2003-06) Pro ce d u re M S C _ A_ H O Proc edur e for H a ndo ve r in M S C -A S he e t5 (2 6) Basic H ando ver to MS C -B Ci rc uit Conne ction r equire d 4 M A P-P REP AR EHA ND OV ER req. [A -H O- RE Q UE ST ] to MS C- B W ait Fo r A ck now ledgem ent fr om M SC -B M AP - P R EP A RE H A N D OV E R r esp . [A- HO- FA ILU R E] fr om MS C -B M A P-P R EP A R EH AN D OV ER resp. [A- H O - RE QU E ST -A C K ] from M SC- B Hando ver Num ber? N ot R equest ed R etry H and over A ttem pt? Y es R equested I_C ON N E CT (IAM ) to M SC - B us ing Hando ver N um ber M A P-P REP AR EHA ND OV ER re s p. [M AP E RR OR ] fr om M S C -B No C ell ? Sam e C ell New C el l W ait for C onnec tion fr om M SC -B 7 1 4 3 Figure 41 (Sheet 5 of 26): Handover control procedure in MSC-A 3GPP
  • 95. Release 1999 95 3GPP TS 23.009 V3.14.0 (2003-06) Procedure MSC_A_H O Sheet6 (26) Proc edure for Hando ve r in MSC-A Wait For Ack nowledgement from MSC-B ERRO R Canc el MAP Re sources Retry Handov er Attempt? Yes A-CLEAR-REQUEST from BSS-A from MSC-B in MSC-A to Network Call Re lease From MS or Network Call Release Release Resource s in BSS-A No Same Cell Canc el MAP Resources Cell? to MS C-B New Cell 1 4 3 IDLE Figure 41 (Sheet 6 of 26): Handover control procedure in MSC-A 3GPP
  • 96. Release 1999 96 3GPP TS 23.009 V3.14.0 (2003-06) Procedure MSC_A_H O Sheet7 (26) Proc edure for Hando ve r in MSC-A W ait for Connec tion from MSC-B I_COMPLETE (ACM) from MSC-B MAP-PA S req. [A-CLEAR-REQ UEST] from MSC-B A-CLEAR-REQUEST from BSS-A (Allowed once in this state) Wait for Connection from MSC-B Queue M es sages for MS in MSC-A (A llowed onc e in this s tate ) Call Release ERROR Han dov er Command to MS via B SS-A From MS or Netwo rk Call Releas e to MS and Network from MSC-B or Network Release Res ources in BSS-A I_DISCONNECT (REL) to MS C-B No Retry Handover A ttempt? Set T103 to MSC-B in MSC-A Cancel MAP Procedures Yes Set Up the Handov er Device Same Cell Cell? Internal mess age in MSC-A I_DISCONNECT (RE L) to MSC-B New Cell W ait for Completion on MS C-B 4 1 3 Figure 41 (Sheet 7 of 26): Handover control procedure in MSC-A 3GPP IDLE
  • 97. Release 1999 97 3GPP TS 23.009 V3.14.0 (2003-06) Procedure MSC_A_H O Sheet8 (26) Proc edure for Hando ve r in MSC-A W ait for Completion on MS C-B MAP-S ENDEND-SIG NA L req. [A-HO-CO MP LE TE] from MSC-B Reset T103 (Allowed once in this state) MAP-PAS req. [A-HO-DE TECT] from MSC-B I-ANSW ER (ANM) from MSC-B MA P-PAS re q. [A-CLEAR-REQUEST] from BSS-B (Allowed once in this state) A-CLEA R-REQ UEST from BS S-A Releas e Resourc es on BSS-A Yes W ait for MS on MSC-B? Co nnect Handov er Device (option) No Wait for Comple tion on MSC-B Forward queu ed messages via MS C-B Us e M AP FORWA RD-ACCESSSIGNAL LING req Call Release to Network and MS Release MAP Resourc es to MSC-B in MS C-A I_DISCO NNECT (REL) to MS C-B Release Resources on BSS-A Call on MSC-B Co nnect Handov er Device (option) IDLE W ait for Co mpletion on MS C-B Figure 41 (Sheet 8 of 26): Handover control procedure in MSC-A 3GPP
  • 98. Release 1999 98 3GPP TS 23.009 V3.14.0 (2003-06) Procedure MSC_A_H O Sheet9 (26) Proc edure for Hando ve r in MSC-A Wait for Comple tion on MSC-B I_DISCONNECT (RE L) from MSC-B A -HANDOV ERFAILURE f rom B SS-A Res et T103 Forward q ueued messages for MS via BSS-A Cancel MAP Procedures Call Re lease Re lease Handov er Device In MSC-A and to MSC-B Release Handover Device Expiry T1 03 Internal to MSC-A Cancel MAP Procedures I_DISCONNE CT (REL) to MSC-B Canc el MAP Proc edures from MSC-B Release Handover Devic e I_DISCONNECT (REL) to MS C-B I_DISCONNE CT (REL) to MSC-B Call in P rogres s on MSC-A In ternal to MSC-A W ait for Co mpletion on MS C-B Releas e Handove r Dev ice in MSC-A to MSC-B from Network Wait for Completion on MSC-B Canc el MAP Proc edures In MSC-A and to MS C-B Re lease Handov er Device In ternal to MSC-A Release Resources BSS-A W ait for Completion on MSC-B IDLE Figure 41 (Sheet 9 of 26): Handover control procedure in MSC-A 3GPP
  • 99. Release 1999 99 3GPP TS 23.009 V3.14.0 (2003-06) Procedure MSC_A_H O Sheet10(26) Proc edure for Hando ve r in MSC-A Call on MS C-B MAP-P AS req. [A-CLEARREQUEST] from MSC-B MAP-PREPARESUB SEQUENTHANDOVER req. [A-HO-REQUEST] from MSC-B 8 Known MSC? No Call on MSC-B Yes Hand ov er allowed to Cell? Yes MSC-B' No From MS or Netwo rk MAP-SEND-ENDSIG NA L resp. to MSC-B Canc el MAP proc edures from MSC-B Call Release Whic h MSC? Call Releas e to Network and MS MSC-A 5 Known BSS? No Yes 6 Res ourc es on new BSS? No I_DISCONNECT (RE L) to MSC-B Yes A -HANDOV ERREQ UEST to BSS-B MAP-PRE PA RESUBSEQUENTHANDOVER res p. [MAP ERROR] to MSC-B MAP-PREPA RESUBSEQUENTHANDOVER res p. [A-HO-FAILURE] to MS C-B No Set T101 Circuit Connection? Yes Wait for Channel Allocation MS on MSC-B Call on MSC-B Figure 41 (Sheet 10 of 26): Handover control procedure in MSC-A 3GPP IDLE
  • 100. Release 1999 100 3GPP TS 23.009 V3.14.0 (2003-06) Procedure MSC_A_H O Sheet11(26) Proc edure for Hando ve r in MSC-A Wait for Channel Alloc ation A-HANDOVERFA ILURE fro m BSS-B A -HANDOV ERREQUEST-ACK. f rom B SS-B M AP -PREPARES UBS EQUE NTHANDOVER resp [ A-HO-REQUEST-ACK] t o MSC-B (Allowed once in this state) MAP-PAS req. [A -CLEAR-REQ UE ST] from MS C-B Releas e Reso urces in B SS-B No Circuit Connection? Call Releas e MAP-SEND-ENDSIGNAL resp to MSC-B I_DISCONNE CT (REL) to MSC-B Release Resourc es in BSS-B Call on MSC-B Yes No Se t Up Handover Dev ice Retry Same Cell? Yes Set T104 Wait for Access by MS MAP-P REPARESUBSEQUENTHA NDOVER res p. [A-HO-FAILURE] to MS C-B Call on MSC-B 6 IDLE Figure 41 (Sheet 11 of 26): Handover control procedure in MSC-A 3GPP From MS or Network Ca nce l Ch annel B SS-B Reset T101 Res et T101 Queue Mess ages for MS in MSC-A Expiry T1 01
  • 101. Release 1999 101 3GPP TS 23.009 V3.14.0 (2003-06) Procedure MSC_A_H O Sheet12(26) Proc edure for Hando ve r in MSC-A Wait for access by MS A-HANDOVERDETE CT from BS S-B A-HANDOVERCOMPLETE from BSS-B Res et T104 No Circuit Connection? Expiry T104 Call Release to Network Yes Connec t Handover Devic e (option) Connect Handover Dev ice (option) Forward q ueued messages for MS via BSS-B Release Resource s on BSS-B Canc el MAP Proc edures MA P-SEND-ENDSIGNA L resp. to MSC-B No in MSC-A to MS C-B I_DISCONNECT (REL) to MSC-B Circuit Conn ec tion? Yes Releas e Handover Dev ice I_DISCONNECT (REL) to MSC-B Call in P rogres s on MSC-A W ait for ac cess by MS IDLE Figure 41 (Sheet 12 of 26): Handover control procedure in MSC-A 3GPP
  • 102. Release 1999 102 3GPP TS 23.009 V3.14.0 (2003-06) Procedure MSC_A_H O Sheet13(26) Proc edure for Hando ve r in MSC-A W ait for acc es s by MS MAP-PAS req. [A-HOFAILURE] from MSC-B A-CLEARREQ UEST from BSS-B Forward queu ed messages via MS C-B MA P-PAS re q. [A -CLEARREQUEST] from MSC-B (Allowed once in this state) Canc el MAP Proc edures Call Releas e from Network (Allowed once in this state) Us e MAP -FORW ARDACCESS-SIGNALLING req. Release Resources on BSS-B Circu it Connec tion? No Yes Re lease Ha ndov er Dev ice Call on MSC-B MS on MS C-B Wait fo r access by MS Figure 41 (Sheet 13 of 26): Handover control procedure in MSC-A 3GPP
  • 103. Release 1999 103 3GPP TS 23.009 V3.14.0 (2003-06) Procedure MSC_A_H O Sheet14(26) Subsequent Handover f rom MSC-B to MSC-B' Circ uit Connection required Proc edure for Hando ve r in MSC-A 5 MA P-PREPARE-HANDOV ER req [A-HO-REQUEST] to MSC-B ' Wait for Ack from MSC-B ' MAP-P REPAREHA NDOVER res p. [A-HO-FAILURE] from MSC-B' MAP-PREPAREHANDOVER resp.. [A-HO-REQUEST-ACK] from MSC-B' Hand ov er Number? Not Reques ted Retry Same Cell? No Requested MAP -PREPARESUB SEQUENTHANDOVER resp. [A-HO-FAILURE] to MSC-B I_CONNECT (IAM) to MSC-B' u sing Handover Number Wait for Connec tion from MSC-B' Yes Call on MSC-B 9 Figure 41 (Sheet 14 of 26): Handover control procedure in MSC-A 3GPP 5
  • 104. Release 1999 104 3GPP TS 23.009 V3.14.0 (2003-06) Procedure MSC_A_H O Sheet15(26) Proc edure for Hando ve r in MSC-A Wait for Ack from MSC-B ' ERROR from MSC-B' Releas e MA P Reso urces from MS C-B o r Network ERRO R Call Re lease Canc el MAP Proc edures to MSC-B ' MAP-PAS req. [A-CLEAR-REQUEST] from MSC-B Retry Same Cell? From MS or Network to MSC-B' MAP-S ENDEND-SIGNA L resp. to MS C-B Cancel MAP Procedures to MSC-B' Release Handover Device Yes No MAP-PREPARE S UBS EQ UE NTHANDO VE R resp. to MSC-B I_DISCONNECT (REL) to MSC-B ERROR Call on MS C-B 5 W ait for Ack from MSC-B' IDLE Figure 41 (Sheet 15 of 26): Handover control procedure in MSC-A 3GPP
  • 105. Release 1999 105 3GPP TS 23.009 V3.14.0 (2003-06) Procedure MSC_A_H O Sheet16(26) Proc edure for Hando ve r in MSC-A W ait for Connec tion from MSC-B' from MSC-B' I_ COMPLETE (ACM) from MSC-B' or Network Set up Handov er Device MAP-PAS req. [A -CLEARREQ UEST] from MSC-B' from MS or Netwo rk ERROR Call Releas e MAP-PA S req. [A-CLEARREQ UE ST] from MSC-B (Allowed once in this state) Wait for Connection from MSC-B' MAP-P REPARESUBSEQUENTHA NDOVER res p. [A-HO-RE QUES T-A CK] to MS C-B to MSC-B' Cancel MAP Procedures to MSC-B' Canc el MAP Proc edures I_ DISCONNECT (RE L) to MSC-B' Queue m es sages for MS in MSC-A Call Release Retry to MSC-B' Cancel MAP Proced ures to MSC-B and MSC-B' MAP -SENDE ND-SI GNAL res p t o MSC-B to Network and MS Yes No Set T103 W ait for Completion on MSC-B' ERROR 5 M AP -PREPARES UBS EQ UE NTHANDO VER resp. to MSC-B I_DISCO NNECT (REL) to MSC-B and MSC-B' Call on MSC-B IDLE Figure 41 (Sheet 16 of 26): Handover control procedure in MSC-A 3GPP
  • 106. Release 1999 106 3GPP TS 23.009 V3.14.0 (2003-06) Procedure MSC_A_H O Sheet17(26) Proc edure for Hando ve r in MSC-A W ait for Completion on MSC-B' MAP-P AS req. [A-HO -DETECT] from MSC-B ' MAP-S ENDEND-SIG NA L req. [A-HO-CO MP LE TE] from MSC-B' Reset T103 MAP-P AS req. [A-CLEARREQUEST] from MSC-B ' I_ANSWER (ANM) from MSC-B ' (Allowed once in this state) (Allowed o nc e in this s tate) Wait fo r access by MS? No Connec t Handover Device (option) Co nnect Handov er Device (option) Forward queu ed messages f or MS via MSC-B' MAP-PA S req. [A-CLEARREQ UE ST] from MSC-B Releas e Hand ov er Dev ice Us e MAP -FORW ARDACCESS-SIGNALLING req. MAP-S ENDEND-SIG NA L resp. to MS C-B to MSC-B and MSC-B' Cancel MAP Procedures I_DISCONNE CT (REL) to MSC-B to Network and MS Call Releas e I_DISCO NNECT (REL) to MSC-B and MSC-B' Redefine MSC-B' as MSC-B Call on MSC-B W ait for Completion from MSC-B' Figure 41 (Sheet 17 of 26): Handover control procedure in MSC-A 3GPP IDLE
  • 107. Release 1999 107 3GPP TS 23.009 V3.14.0 (2003-06) Pro ce d u re M S C _ A_ H O S he e t1 8 ( 26 ) Proc edur e for H a ndo ve r in M S C -A W ait for C omple tion o n MS C - B ' MA P- P AS re q. [A -H O - FAILU RE] from M SC- B Expir y T103 Res et T103 Ca nc el M A P P r oc edur es to MSC - B' fro m M S C- B fr om MS C - B' C anc el M AP P r oc edur e s C an cel M A P P r ocedure s I_D IS C ONN EC T ( R EL ) to M SC- B Fr om Netw ork or MS C -B C al l Rel eas e I_DIS C ON N EC T (R EL) to M S C -B ' R elease H ando ver D evic e R eleas e H andover D evic e R elease Ha ndov er D ev ice Yes W ait for acce s s by M S? I_ DIS C ON NE C T (R E L) to M SC -B ' No M S C- B C onnec tion? Yes C ancel M AP P r ocedures to M SC- B ' No U se M AP FOR W ARD AC CE SS SIGN A LLIN G r eq. C all Re lease ID LE Forw ar d queued m es sages for M S via M SC -B I_D ISC ON N E CT ( R EL) to MS C - B ' to Netwo rk Cal l on MSC -B ID LE Figure 41 (Sheet 18 of 26): Handover control procedure in MSC-A 3GPP W ai t for Com ple ti on on MS C -B '
  • 108. Release 1999 108 3GPP TS 23.009 V3.14.0 (2003-06) Pro ce d u re M S C _ A_ H O Proc edur e for H a ndo ve r in M S C -A S he e t1 9 ( 26 ) Basic H ando ver to M S C -B no C ircuit C onnecti on r equ ir ed 7 Q ueue M es sa ges for M S i n M S C -A H an dov er C om mand to M S via B S S -A S et T103 W ait for MS o n MS C- B M A P-S EN D E ND - S IG NA L r eq. [A -H O- CO MP LE TE] fr om M SC -B R eset T103 M AP -PA S r eq. [A- CLE AR - RE QU E ST ] fro m BS S- B ( A llow ed once i n th is state) ( A llo wed once i n thi s state) R eleas e R esourc es o n B SS - A Yes R elease R eso urces on BS S -A M AP -P A S r eq. [A-H O- DE TECT ] fr om M S C -B A - CLE A R- RE Q UE S T fr om B S S- A W ait fo r M S on M SC - B? No For war d queu ed m essag es f or MS vi a MS C- B Us e M AP FOR W A RD - AC C E S SS IGN A LLIN G r eq. W ait for MS o n M S C -B to N etw ork and MS R elease M AP R esourc es MS on M S C- B C all R elease to M SC- B i n MS C- A ID LE W a it fo r MS on MS C- B Figure 41 (Sheet 19 of 26): Handover control procedure in MSC-A 3GPP
  • 109. Release 1999 109 3GPP TS 23.009 V3.14.0 (2003-06) Procedure MSC_A_H O Sheet20(26) Proc edure for Hando ve r in MSC-A Wait for MS on MSC-B A -HANDOV ERFAILURE f rom B SS-A Cancel MAP Procedures Res et T103 Forward q ueued messages for MS via BSS-A in MSC-A to MSC-B from MS C-B In MSC-A and to MSC-B Relea se Res ources BSS-A Expiry T103 Call Re lease from Network Canc el MAP Proc edures Release Resourc es BS S-A Cancel MAP Procedures Call in P rogres s on MSC-A Wait for MS on MSC-B IDLE W ait for MS on MS C-B Figure 41 (Sheet 20 of 26): Handover control procedure in MSC-A 3GPP
  • 110. Release 1999 110 3GPP TS 23.009 V3.14.0 (2003-06) Procedure MSC_A_H O P rocedure fo r Handover in MSC-A Sheet21(26) MS Es tablished on MSC-B without a Circ uit Connection MS on MS C-B Reques t fo r Circ uit Establishment From MSC-B Canc el MAP Proc edures MAP -PREPARE- Call S UBS EQ UE NTRelease HANDO VE R req. [A-HO-REQUEST] from MS C-B From MS or Network Call Releas e to Network MAP-SEND-ENDS IG NAL resp. to MSC-B MAP-P REPAREHA NDOVER req. [NULL] [A-AS G-REQUEST] to MS C-B Wait For Res ponse from MSC-B 8 IDLE Figure 41 (Sheet 21 of 26): Handover control procedure in MSC-A 3GPP
  • 111. Release 1999 111 3GPP TS 23.009 V3.14.0 (2003-06) Procedure MSC_A_H O Sheet22(26) Circ uit Connection Establis hme nt to MS C-B Proc edure for Hando ve r in MSC-A Wait Fo r Res ponse from MSC-B MAP-PREPAREHANDOVER resp. [Handover Number] [A -ASG-CO MP LETE] from MSC-B Call Release I_CONNECT (IAM) to MSC-B us ing Handover Number From MS or Netwo rk MAP-SENDEND-SIGNAL resp. to MSC-B Wait for Comple te from MSC-B IDLE Figure 41 (Sheet 22 of 26): Handover control procedure in MSC-A 3GPP
  • 112. Release 1999 112 3GPP TS 23.009 V3.14.0 (2003-06) Procedure MSC_A_H O Sheet23(26) Proc edure for Hando ve r in MSC-A Wait For Respons e from MSC-B MAP-P REPAREHANDOVER resp. [M AP ERROR] from MSC-B M AP -PREPAREHANDOVER resp. [A-ASG-FAILURE] from MS C-B No MA P-PAS req. [A-CLEAR-REQUEST] from MSC-B Retry? Canc el MAP Proc edures (Allowed onc e Call in this s tate ) Release from MSC-B to Network Yes MAP-P REPAREHA NDOVER req. [NULL] [A-AS G-REQUEST] to MS C-B Wait For Respons e from MSC-B Failure Respons e to Circuit E stablis hment Request MS on MSC-B MS on MSC-B Failure Re sponse to Circuit Establishment Re quest IDLE Figure 41 (Sheet 23 of 26): Handover control procedure in MSC-A 3GPP
  • 113. Release 1999 113 3GPP TS 23.009 V3.14.0 (2003-06) Procedure MSC_A_H O Sheet24(26) Proc edure for Hando ve r in MSC-A W ait for Complete from MSC-B I_COM PLE TE (ACM) from MSC-B MAP-PAS req. [A-CLE ARREQUEST] from MSC-B (Allowed on ce in this state) Call Releas e From MS or Network I-ANSW ER (ANM) from MSC-B from MS C-B Succes s Call on MSC-B Res po nse to Circ uit Establishment Request Respons e to Circuit E stablis hment Request Wait for Complete from MSC-B MAP-S ENDEND-SIGNAL res p. to MSC-B Canc el MAP Proc edures I_DISCONNE CT (REL) to MSC-B Fa ilure IDLE Figure 41 (Sheet 24 of 26): Handover control procedure in MSC-A 3GPP
  • 114. Release 1999 114 3GPP TS 23.009 V3.14.0 (2003-06) Pro ce d u re M S C _ A_ H O Proc edur e for H a ndo ve r in M S C -A S he e t2 5 ( 26 ) Subsequent Hando ver f rom MS C - B to M SC - B' no C ir cuit C onnection r equ ired. 9 M A P-P REP AR ES U B SE QU E N THA ND OV ER res p. [A -H O- RE QU ES T-A CK ] to MS C- B Q ueue M es sa ges for M S i n M S C -A S et T103 W ait for MS o n MS C - B ' M A P-S EN D E N D- S IGN A L r eq [A -H O- CO MP LE TE] from M SC -B' R eset T103 For war d queu ed m essag es f or MS vi a MS C- B M A P-P AS r eq. [A -C LE A R RE Q UE ST ] from M SC -B' M AP -P AS req. [A- HO -D E TE C T] fr om MS C -B ' Yes ( A ll owed once i n this sta te) Us e M AP FOR W A RD - AC C E S SS IGN AL LIN G r eq C an c el M A P Pr oc edur es to N e tw ork and MS W ait for MS on M SC -B' M A P-PA S r eq. [A -C LE A R RE Q UES T ] fr om M S C -B W ait for acces s by M S ? No to M S C -B and M SC -B ' R edefin e M SC - B ' a s M S C- B MS on M S C- B ( Allow ed o nc e in this s tate) C all R elease ID LE Figure 41 (Sheet 25 of 26): Handover control procedure in MSC-A 3GPP
  • 115. Release 1999 115 3GPP TS 23.009 V3.14.0 (2003-06) Procedure MSC_A_H O Sheet26(26) Proc edure for Hando ve r in MSC-A W ait for MS on MSC-B' MA P-PAS re q. [A-HOFAILURE] from MSC-B Expiry T103 Res et T103 Forward queu ed messages f or MS via MS C-B Ca nc el MAP Proc edures MS on MSC-B from MSC-B to MSC-B' to MSC-B ' Call Re lease from Network or MSC-B Cancel MAP Procedures W ait for acces s by MS? No Us e M AP FORW ARDACCESSSIGNALLING req. Canc el MAP Proc edures from MSC-B' Yes Cancel MAP Procedures IDLE W ait for MS on MSC-B' Figure 41 (Sheet 26 of 26): Handover control procedure in MSC-A 3GPP
  • 116. Release 1999 116 3GPP TS 23.009 V3.14.0 (2003-06) Procedure MSC_B_H O Sheet1 (18) Procedures fo r Handover in MSC-B IDLE MAP-PREPARE-HANDO VER req. [A-HO-REQUEST] from MSC-A Known BSS? No Yes Not Requ es ted Hand ov er Number? Requested MA P-ALLOCATE HANDOVER-NUMBE R req. to VLR MAP-PRE PA REHANDOV ER res p [A-HO-FAILURE] to MSC-A Set T201 A-HANDOVERREQ UE ST to BSS-B Wait for Channel or Handov er Number IDLE Figure 42 (Sheet 1 of 18): Handover control procedure in MSC-B 3GPP
  • 117. Release 1999 117 3GPP TS 23.009 V3.14.0 (2003-06) Procedure MSC_B_H O Sheet2 (18) Procedures fo r Handover in MSC-B Wait for Channel or Handover Number A -HANDOV ERREQ UEST-ACK from B SS-B MAP-A LLOCATEHANDOVERNUMBER res p. from VLR Reset T201 Handover Number? Requested Not Requested W ait for Handover Number A lloca tion MAP-PREPAREHANDO VE R resp. [A-HO-REQUEST-ACK] to MSC-A W ait for Channel Allocation MAP-ALLOCATEHANDOVERNUMBE R resp. from VLR A-HANDOVERREQUEST-ACK from BSS-B Reset T201 MAP-PREPARE HANDO VE R resp. [A-HO -REQUEST-ACK] [Handov er Number] to MSC-A Set T204 S et T210 Wait for MS on B SS-B W ait for Connection from MS C-A Figure 42 (Sheet 2 of 18): Handover control procedure in MSC-B 3GPP
  • 118. Release 1999 118 3GPP TS 23.009 V3.14.0 (2003-06) Procedure MSC_B_H O Sheet3 (18) Procedures fo r Handover in MSC-B W ait for Channel or Handov er Number Wait for Channel Alloc ation A-HANDOVERFAILURE from BSS-B Release Resources in BSS-B Retry Same Cell? Yes W ait for Channel or Handover Number Ex piry T201 W ait for Handov er Number Allocation A-CLEA R-REQ UEST from BS S-B ERRO R Relea se Res ources in BSS-B MAP-P REPAREHA NDOVER res p. [MAP E RROR] to MS C-A No Set T201 Canc el Channel on BSS-B MAP-PRE PARE HANDOVER resp. [A-HO-FAILURE] to MSC-A A-HANDOVERREQUEST to BS S-B W ait for Channel or Handov er Number Indication from VLR IDLE IDLE Figure 42 (Sheet 3 of 18): Handover control procedure in MSC-B 3GPP
  • 119. Release 1999 119 3GPP TS 23.009 V3.14.0 (2003-06) Procedure MSC_B_H O Procedures fo r Handover in MSC-B Sheet4 (18) Ba sic handover f rom MS C-A to MSC-B Circ uit Connection required W ait for Connec tion from MSC-A I_CONNECT (IAM) from MSC-A (Us es Handover No.) Reset T210 To MSC-A in MSC-B Ex piry T210 Cancel MAP Procedures A-CLE AR-REQUEST f rom B SS-B Cancel MAP Procedures MAP-PAS req. [A -CLEARRE QUES T] to MS C-A e.g. MAP-ABO RT from MSC-A Canc el MAP Proc edures MAP -SEND-HANDOV ERREPORT res p. to VLR-B Set T204 I_COMPLETE (ACM) to MS C-A W ait for acc es s by MS on BSS-B Release Radio Resourc es o n BS S-B I DLE Figure 42 (Sheet 4 of 18): Handover control procedure in MSC-B 3GPP To MSC-A in MSC-B
  • 120. Release 1999 120 3GPP TS 23.009 V3.14.0 (2003-06) Procedure MSC_B_H O Sheet5 (18) Procedures fo r Handover in MSC-B W ait for acc es s by MS on BSS-B A-HANDOVERCOMPLE TE from BSS-B A -CLEARREQ UEST from B SS-B Expiry T2 04 from MSC-A MAP-P AS req [A -CLEARREQ UEST] to MSC-A Reset T204 Yes Cancel MAP Procedure Res et T204 I_DISCONNE CT (REL) to MSC-A ANM Sent? Releas e Res ourc es on BSS-B I_DISCO NNECT (REL) from MSC-A No A-HANDOVERDETECT from BSS-B I_ANS WER (ANM) to MS C-A to MSC-A in MSC-B MAP-S ENDEND-SIG NA L req. [A-HO-CO MP LE TE] to MS C-A Call in Progres s on MS C-B Cancel MAP Procedures I _ANSW ER (ANM ) t o MSC-A Release Resources on B SS-B MAP-P AS req [A-HO-DE TECT] to MS C-A W ait for acc es s by MS on BSS-B I DLE Figure 42 (Sheet 5 of 18): Handover control procedure in MSC-B 3GPP Wait for Disc onnect
  • 121. Release 1999 121 3GPP TS 23.009 V3.14.0 (2003-06) Procedure MSC_B_HO Sheet6(18) Procedures for Handover in MSC-B Forward Messages to MS Call in Progress on MSC-B MAP-SENDEND-SIGNAL resp . fro m MSC-A A-CLEAR-REQUEST from BSS-A A-HO-PERFORMED from BSS MAP-PAS req . [A-CLEAR-REQ UEST] to MSC-A MAP-PAS req . [A-HO-PE RFORMED] to MSC-A Can cel MAP Procedures Call in Progress on MSC-B Release Resources I_DISCONNECT in BSS-A (REL) from MSC-A MSC-A disconnected? Can cel MAP Procedures Yes Release Resources in BSS-A from MSC-A A-HANDO VERREQUIRED from BSS-A No Wait for Disconnect I_DISCONNECT (REL) to MSC-A I_DISCONNECT (REL) from MSC-A IDLE Call in Progress on MSC-B IDLE Figure 42 (Sheet 6 of 18): Handover control procedure in MSC-B 3GPP 2
  • 122. Release 1999 122 3GPP TS 23.009 V3.14.0 (2003-06) Procedure MSC_B_H O Sheet7 (18) Procedures fo r Handover in MSC-B 2 Known MSC? 4 Yes No Handover allowed to Cell? Yes No MSC-A/MSC-B' Which MSC? MS C-B MAP-P REPARESUBSEQUENTHA NDOVER req. [A-HO-REQ UEST] to MS C-A Known BSS? No Yes Yes Select New Cell? Resources on BSS-B? 1 No No Yes No Send Rejec t? Yes A-HANDOVERREJECT to BS S-A Circuit Conn ec tion? Set T211 No Yes Call in P rogres s on MSC-B MS on MSC-B 3 Wait for Respons e Figure 42 (Sheet 7 of 18): Handover control procedure in MSC-B 3GPP
  • 123. Release 1999 123 3GPP TS 23.009 V3.14.0 (2003-06) Pro ce d u re M S C _ B_ H O Pr ocedure s fo r Han dover in M S C- B S he e t8 (1 8) Hando ver from B SS -A to B SS - B on M S C -B 3 A -H AN DOV E R- R EQ U ES T to B S S- B S et T201 W ait for C hanne l A -H AN D OVE R R EQU E S T- ACK from BS S -B A - H A ND OV E R F AILUR E fr om BS S- B E x piry T 201 R eset T201 R eset T 201 A - CLEA R -R EQU ES T fr om BS S - A M A P- P AS req [A-C LE AR R EQ UE ST ] to M S C- A Q ueue M es sa ges i n M SC -B H an dov er C om mand to M S via B S S -A R eleas e R e sour ces C anc el M A P on B S S- B Pr oc edures S et U p H andov er D evice R etry H and over A ttem pt? Y es S et T202 Cancel C han nel re ques t on B S S-B T o M SC -A i n M SC -B R el ease Res ource s on B S S-A No C ell ? Sam e C el l W ait for a cc es s by MS M A P - SE N D- END S IG NA L r esp. f rom MS C- A 3 New C el l 2 1 Figure 42 (Sheet 8 of 18): Handover control procedure in MSC-B 3GPP W ai t for D isc onnect
  • 124. Release 1999 124 3GPP TS 23.009 V3.14.0 (2003-06) Pro ce d u re M S C _ B_ H O S he e t9 (1 8) Pr ocedure s fo r Han dover in M S C- B W ait for a cc es s by MS A -H AN D OVE R COM PL E TE from BS S -B A -H A ND OV ER D E T E CT for m B SS -B A- H A ND OV ER F A IL UR E f rom B S S-A R eset T202 M A P-P AS r eq. [A -H O- PE RF OR M E D] to MS C- A C ircu it C onnec tion? No Cir cuit Conn ection? Y es No Ye s Co nnect H andov er D evice (O pti onal) Connect Handover Devi ce (Option al) R e set T2 02 For war d queu ed m essag es vi a BS S- B Fo r wa rd queu ed m essage s via BS S- A R elease R eso urces in BS S- A R elease R esource s in B S S- B C ircu it C onnec tion? No No Y es Y es Re lease H andov er D evice C all i n Progre s s o n MS C- B C irc uit C o nnec tion? R elease H andov er D evice MS on MS C- B MS on M S C -B W ait for access by M S C a ll i n P rogres s on MS C- B Figure 42 (Sheet 9 of 18): Handover control procedure in MSC-B 3GPP
  • 125. Release 1999 125 3GPP TS 23.009 V3.14.0 (2003-06) Procedure MSC_B_H O Sheet10(18) Procedures fo r Handover in MSC-B W ait for acc es s by MS Expiry T202 A-CLEAR-REQ UEST from BSS-B Release Resources in BSS -B and B SS-A Release Resources in BSS-B Release Res ourc es in BS S-A Yes Re lease Handov er Device MAP-PAS req. [A-CLEAR-REQUEST] to MS C-A Canc el MAP Proc edures W ait for acce ss by MS? No Release Resource s in BSS -B and B SS-A MA P-PAS req. [A-CLEAR-REQUEST] to MSC-A To MSC-A in MSC-B To MS C-A in MSC-B I_DISCONNE CT (REL) to MSC-A IDLE MAP-SEND-ENDSIGNAL resp. from MSC-A A-CLEAR-REQUEST from BSS-A Canc el MAP Proc edures Release Handov er Device Release Resourc es in BS S-B Wait for access by MS W ait for Dis connect W ait for Dis connec t Figure 42 (Sheet 10 of 18): Handover control procedure in MSC-B 3GPP
  • 126. Release 1999 126 3GPP TS 23.009 V3.14.0 (2003-06) Pro ce d u re M S C _ B_ H O Pr ocedure s fo r Han dover in M S C- B S he e t1 1 ( 18 ) Su bsequent H ando ver fr om M S C -B to M SC- A W ait for Res ponse M AP - PR EP ARE S U BS E Q UEN TH A N DO VE R r esp. [A - HO- R E QU E ST - A CK ] fr om MS C- A M AP -PR EP AR ES UBS EQ UE NT H A N DO V ER r esp. [A - HO -FA ILU R E or M AP E RR O R ] fr om MS C- A Res et T2 11 E xp iry T2 11 M AP -PA S r eq. [A-C LE AR R EQ UE ST ] to M S C- A R eset T 211 M AP R e lea se Res our ces -SE N D -EN D S IGN AL re sp. i n B S S-B fr om M S C -A R etr y H andover A ttem pt? H an dover Com m and to M S via B S S- A A - C LE AR R E QU E ST fro m B S S- A i n M S C -B to M S C- A Cancel MA P Procedur es No Yes S et T2 04 Sam e C el l R el ease Res ource s in B S S-A C ell ? N ew C ell W ait for A ck . fr om MS C- A 2 4 1 Figure 42 (Sheet 11 of 18): Handover control procedure in MSC-B 3GPP W ai t for D isc onnect
  • 127. Release 1999 127 3GPP TS 23.009 V3.14.0 (2003-06) Pro ce d u re M S C _ B_ H O S he e t1 2 ( 18 ) Pr ocedure s fo r Han dover in M S C- B W ait fo r Ack . fr om MS C- A M A P- S E ND E ND S IGN AL res p. fr om M S C -A E x piry T 204 Relea se Res our ces MA P- PA S re q. [A-C LE AR -R E QU E ST] in BS S -A to M S C -A Res et T204 R elease Res o urces Cance l MAP in BS S-A Pr ocedures to M S C -A i n M S C- B to M SC -A Ci rcuit C onn ec tion? No Re set T204 M AP -P A S r eq. [A-H O- FA ILU RE ] to MS C -A R e lease R esourc es in B SS - A C anc el M AP P r oc edur e s Circu it C onnec tion? Yes W ait fo r D isc onnect A -H A N D OV E R FA ILU RE from B S S-A A- C LEA R -R EQU ES T from BS S-A No Yes C all in P rogres s on MS C- B IDLE Figure 42 (Sheet 12 of 18): Handover control procedure in MSC-B 3GPP MS on MS C- B
  • 128. Release 1999 128 3GPP TS 23.009 V3.14.0 (2003-06) Proce dure MSC_B_H O Proce dures for Ha ndov er in MSC-B Sheet13(18) Basic han dover from MSC-A to MSC-B no Circ uit Connect ion required W ait for MS on BSS-B A-HANDOVERCOMPLE TE from BSS-B A-CLEARREQUEST from BSS-B Reset T2 04 E xp iry T204 MAP-P AS req [A-CLEARREQ UEST] to MS C-A MAP -SENDEND-SIGNAL req. [A -HO-COMPLETE] to MSC-A A-HANDOVERDETECT from BSS-B MA P-PAS req. [A-HO-DE TECT] to MSC-A MS on MSC-B Canc el MAP Proc edure from MS C-A Cancel MAP Procedures to MSC-A in MS C-B Release Resourc es on BSS-B Wait fo r MS on BSS-B IDLE Figure 42 (Sheet 13 of 18): Handover control procedure in MSC-B 3GPP
  • 129. Release 1999 129 3GPP TS 23.009 V3.14.0 (2003-06) Procedure MSC_B_H O Sheet14(18) Procedures fo r Handover in MSC-B Forward Mess ages to MS MS on MS C-B MA P-SENDEND-SIG NAL resp. from MSC-A A-HANDOVERREQ UIRED fro m BSS-A MAP-PREPAREHANDOVER req. [NULL] [A-ASG-REQ UE ST] from MSC-A MAP-ALLOCATEHANDOV ER-NUMBER req. to VLR Releas e Resources in BSS-B A-ASSIGNMENTREQUEST to B SS-A IDLE 2 Wa it f or Ass ignmen t or Han dov er Number Figure 42 (Sheet 14 of 18): Handover control procedure in MSC-B 3GPP
  • 130. Release 1999 130 3GPP TS 23.009 V3.14.0 (2003-06) Procedure MSC_B_H O Procedures fo r Handover in MSC-B Sheet15(18) Circ uit Connection Es tablis hment on MS C-B Wait for Assignment or Handover Number A-ASSIGNMENTCOMPLE TE from BSS-A MAP-ALLOCATEHANDOVERNUMBE R resp. from VLR Wait for Handover Number Alloc ation W ait for Ass ignment MAP-ALLOCATEHANDOVERNUMBE R resp. from VLR A-ASSIGNME NTCOMPLETE from BS S-A M AP -PREPAREHANDO VER resp. [Handover Numbe r] [A-ASG-COMPLETE] to MSC-A Set T210 Wait for Connect from MSC-A Figure 42 (Sheet 15 of 18): Handover control procedure in MSC-B 3GPP
  • 131. Release 1999 131 3GPP TS 23.009 V3.14.0 (2003-06) Procedure MSC_B_H O Sheet16(18) Procedures fo r Handover in MSC-B W ait for Ass ignment or Handov er Number Wait for Assignment A-ASSIGNMENTFAILURE from BSS-A MAP-P REPAREHA NDOVER res p. [A-AS G-FA ILURE] to MS C-A Wait for W ait for W ait for Assignment or Handover Number As signment or Handover Number A lloca tion Handover Numb er E RROR W ait for Assignment Wait fo r Handov er Number Allocation MAP-S ENDEND-SIG NA L resp. from MSC-A Indication fro m VLR M AP -PREPAREHANDO VER resp. [MAP ERROR] to MSC-A A-CLEAR-REQUEST from BSS-A MAP-PA S req. [A-CLEAR-REQ UEST] to MSC-A to MSC-A a nd VLR-B Canc el MAP Proc edures to VLR-B Cancel MAP Procedures Release Res ources in BSS-A MS on MSC-B IDLE Figure 42 (Sheet 16 of 18): Handover control procedure in MSC-B 3GPP
  • 132. Release 1999 132 3GPP TS 23.009 V3.14.0 (2003-06) Procedure MSC_B_H O Sheet17(18) Procedures fo r Handover in MSC-B Wait for Connect from MSC-A I_CONNECT (IAM) from MSC-A (Uses Handover No.) Res et T210 to MSC-A in MSC-B Expiry T210 Call on MS C-B MAP-PA S req. [A-CLEAR_REQ UE ST] to MS C-A Cancel MAP Procedures MAP-SEND-HANDOVERREP ORT resp . to VLR-B I_COMPLETE (ACM) to MS C-A A-CLEAR-REQUEST fro m BSS-A Canc el MAP Proc edures to MS C-A in MSC-B Release Radio Resources on BSS-A IDLE Figure 42 (Sheet 17 of 18): Handover control procedure in MSC-B 3GPP
  • 133. Release 1999 133 3GPP TS 23.009 V3.14.0 (2003-06) Procedure MSC_B_H O Sheet18(18) Procedures fo r Handover in MSC-B Wait for Connect from MSC-A MAP-SENDEND-SIGNAL res p. from MSC-A I_DISCONNECT (REL) from MSC-A from MSC-A Release Resources on BS S-A MS on MS C-B Cancel MAP Procedure Releas e Res ourc es on BSS-A IDLE Figure 42 (Sheet 18 of 18): Handover control procedure in MSC-B 3GPP IDLE
  • 134. Release 1999 134 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet1 (78) Procedure for Handove r in 3G_MSC-A IDLE Call in P rogres s on 3G_MS C-A A-HANDO VE R-REQ UIRED from BSS-A (GS M to UMT S Han dov er) Known MSC? Iu-REL OCAT IO N-REQ UIRED from RNS-A Yes Type of handover No No To GSM From MS or Network Imp licit Releas e of B SS-A S RNS Reloc ation Handover allowed to Cell? 11 Call Releas e 10 Yes W hic h M SC? 3G_MSC-B 3G_MSC-A No Known RNS? Yes 3 No Resources o n RNS-B? Yes No Send Rejec t? Yes A-HANDOVERREJECT to BS S-A Call in P rogres s on 3G_MS C-A (G SM) 2 4 Figure 43 (sheet 1 of 78): Handover control procedure in 3G_MSC-A 3GPP IDLE
  • 135. Release 1999 135 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Procedure for Handove r in 3G_MSC-A Sheet2 (78) Handover on 3G_MSC-A from BSS-A to RNS-B. 2 Iu RELOCATIO N-REQ UE ST to RNS-B Set T501 Wait for Channel Allocation Intra-MSC Iu-RELOCATIONREQUEST-ACK from RNS-B Iu-RELOCATIO N FAIL URE from RNS-B From UE/MS or Network E xpiry T 501 Reset T501 Call Release Han dov er Command to UE/MS via B SS-A Set Up Handov er Device A-CLEARREQUEST from BSS-A Reset T501 Queue M es sages for UE/MS in 3G_MSC-A Call Releas e to Network Releas e Res ources in BSS-A Cancel Channel in RNS-B Cancel Channel in RNS-B Internal mess age in 3G_MSC-A Set T502 W ait for acces s by UE/MS on RNS/BSS (G SM to UMTS Ho) IDLE 3 Figure 43 (sheet 2 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 136. Release 1999 136 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet3 (78) Procedure for Handove r in 3G_MSC-A Wait for acces s by UE /MS on RNS/BSS (GS M to UM TS Ho) Iu-RELOCAT IO N DETE CT from RNS-B Iu-RELOCATION COMPLETE from RNS-B Connect the Handove r Dev ice (O ption) Connect the Handover Devic e (Option) Only if not already connec ted Res et T502 Releas e Res ources in BSS-A Forward queued me ssages for UE/MS via RNS-B Call in P rogres s on 3G_MS C-A (UT RAN) W ait for ac cess by UE/MS on RNS/B SS (GSM t o UMTS handover) Figure 43 (sheet 3 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 137. Release 1999 137 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet4 (78) Procedure for Handove r in 3G_MSC-A W ait for Ac cess by UE/MS On RNS/BSS (G SM to UMTS Ho) A-CLEARREQ UEST from B SS-A A-HANDOVERFAILURE from BSS-A Reset T502 Forward queued messages for UE/MS v ia BSS-A (Allowed onc e in this state) Iu-REL EA SE REQ UEST from RNS-B Releas e Res ources in RNS-B Yes (Allowed once in this state) Release Resourc es in BS S-A Expiry T5 02 Call Releas e Release Resource s in BSS-A Release Ha ndover Device W ait for UE/MS on BSS-B? No Re lease Re sources in RNS -B Reset T502 Release Resourc es in RNS-B Release Ha ndover Device Call Release to Network Releas e Handover Devic e Call in Progres s on 3G_MSC-A (G SM ) Wait for access by UE/MS on RNS /B SS (GSM to UMTS Ho) IDLE Wa it for acces s by UE /MS on RNS/BSS (G SM to UMTS Ho) Figure 43 (sheet 4 of 78): Handover control procedure in 3G_MSC-A 3GPP From Network
  • 138. Release 1999 138 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet5 (78) Procedure for Handove r in 3G_MSC-A 10 Known MSC? Yes No No Handover allowed to Cell? Yes Which MSC? MSC-B 3G_MS C-A No Known BSS? Yes 12 No Resources on BSS-B? Yes Iu-RELOCATION PREP ARATION F AIL URE to RNS-A Call in P rogres s on 3G_MS C-A (UT RAN) 13 14 Figure 43 (sheet 5 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 139. Release 1999 139 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Procedure for Handove r in 3G_MSC-A Sheet6 (78) Handover on 3G_MSC-A from RNS-A to BSS-B. 13 A-HANDO VER -REQUEST to BS S-B Set T301 Wait for Channel Allocation Intra-MSC A-HANDOVERREQUEST-ACK from BSS-B A-HANDOVERFA ILURE from BSS-B From UE/MS or Network E xpiry T 301 Reset T301 Call Release Han dov er Command to UE/MS via Iu-RELOCATION Command to RNS-A Set Up Handov er Device Iu-RELEASEREQUEST from RNS-A Reset T301 Queue M es sages for UE/MS in 3G_MSC-A Call Releas e to Network Releas e Res ources in RNS-A Cancel Channel in B SS-B Cancel Channel in BSS-B Internal mess age in 3G_MSC-A Set T302 W ait for acces s by UE/MS on B SS/RNS (UMTS to GSM Ho) IDLE 12 Figure 43 (sheet 6 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 140. Release 1999 140 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet7 (78) Procedure for Handove r in 3G_MSC-A Wait for access by UE/MS on BSS/RNS (UMTS to GSM han dov er) A-HANDO VE R-DET ECT from BSS-B A -HANDOVER-COMPLETE from BS S-B Connect the Handover Dev ice (O ption) Only if not alread y connec ted Connec t t he Handov er Devic e (Option) Res et T302 Releas e Res ources in RNS-A Forward queued mes sages for UE/MS via B SS-B W ait for ac cess by UE/MS on B SS/RNS (UMT S to GSM Ho) Call in Progress on 3G_MSC-A (GSM) Figure 43 (sheet 7 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 141. Release 1999 141 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet8 (78) Procedure for Handove r in 3G_MSC-A W ait for Ac cess by UE/MS On RNS/BSS (UMTS to GSM Ho) Iu-RELOCATIONCANCEL from RNS-A Reset T302 Forward queued messages for UE/MS via RNS-A (Allowed onc e in this state) (Allowed once in this state) Iu-REL EA SE REQ UEST from RNS-A Release Resourc es in RNS-A A-CLEAR REQ UEST from B SS-B Releas e Res ources in BSS-B Re lease Re sources in BSS -B Yes Expiry T3 02 Release Resource s in RNS-A Call Releas e Release Ha ndover Device W ait for UE/MS on BSS-B? No Reset T302 Release Resourc es in BS S-B Release Ha ndover Device Call Release to Network Releas e Handover Devic e Call in Progres s on 3G_MSC-A (UT RAN) Wait for access by UE/MS on RNS /B SS (UMTS to GSM Ho) IDLE Wa it for acces s by UE /MS on RNS/BSS (UMTS to GSM Ho) Figure 43 (sheet 8 of 78): Handover control procedure in 3G_MSC-A 3GPP From Network
  • 142. Release 1999 142 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet9 (78) Procedure for Handove r in 3G_MSC-A 11 Yes Known 3G_MSC? No Which 3G _MSC? 3G_MSC-B 3G_MS C-A Known RNS? No Yes 16 Resources on RNS-B? No Yes Iu-RELOCATION PREP ARATION F AIL URE to RNS-A Call in P rogres s on 3G_MS C-A (UT RAN) 15 17 Figure 43 (sheet 9 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 143. Release 1999 143 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Procedure for Handove r in 3G_MSC-A Sheet10(78) SRNS Relocation on 3G_MSC-A from RNS -A to RNS-B 15 Iu-RELOCATION -REQUEST to RNS-B Set T701 Wait for Channel Allocation Intra-3G_MS C Iu-RELOCATIONREQUEST-ACK from RNS-B Iu-RELOCATIO N FAIL URE from RNS-B From UE or Network E xpiry T 701 Reset T701 Call Release Iu-RELOCATION Command to RNS-A Set Up Handov er Device Iu-RELEASEREQUEST from RNS-A Reset T701 Queue M es sages for UE in 3G_MSC-A Call Releas e to Network Releas e Res ources in RNS-A Cancel Channel in RNS-B Cancel Channel in RNS-B Internal mess age in 3G_MSC-A Set T702 W ait for acces s by UE on RNS (SRNS Relocation) IDLE 16 Figure 43 (sheet 10 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 144. Release 1999 144 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet11(78) Procedure for Handove r in 3G_MSC-A Wait for acces s by UE on RNS (SRNS RELO CATION) Iu-RELOCAT IONDET ECT from RNS-B Iu-RELO CATIONCOMPLETE from RNS-B Connect the Handove r Dev ice (O ption) Conne ct the Handover Devic e (Option) Only if not already connec ted Res et T702 Releas e Res ources in RNS-A Forward queued mes sages for UE via RNS-B W ait for ac cess by UE on RNS (SRNS Reloca tio n) Call in P rogress on 3 G_MS C-A (UT RAN) Figure 43 (sheet 11 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 145. Release 1999 145 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet12(78) Procedure for Handove r in 3G_MSC-A W ait for Ac cess by UE O n RNS (SRNS Relocation) Reset T702 Forward queued messages f or UE via RNS-A (Allowed once in this state) Iu-REL EA SE REQ UEST from RNS-A Iu-RELOCATIONCANCEL from RNS-A (Allowed onc e in this state) Release Resourc es in RNS-A Iu-REL EA SE REQ UEST from RNS-B Releas e Res ources in RNS-B Yes Expiry T7 02 Call Releas e Release Resource s in RNS-A Release Ha ndover Device W ait for UE on RNS-B? No Re lease Re sources in RNS -B Reset T702 Release Resourc es in RNS-B Release Ha ndover Device Call Release to Network Releas e Handover Devic e Call in Progres s on 3G_MSC-A (UT RAN) Wait for access by UE on RNS (SRNS Relo cation) IDLE Wa it for acces s by UE on RNS (SRNS Re location) Figure 43 (sheet 12 of 78): Handover control procedure in 3G_MSC-A 3GPP From Network
  • 146. Release 1999 146 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Procedure for Handove r in 3G_MSC-A Sheet13(78) Bas ic GS M to UMT S han dov er to 3G_MSC-B Circuit Connection required 4 MAP-P REPAREHA NDOVER req. [A-HO-REQ UEST ] to 3G_MS C-B Wait For Ack nowledgement from 3G_MSC-B (G SM to UMTS Ho) Handover Number? MAP-P REPAREHA NDOVER res p. [MAP ERROR] from 3G_MSC-B MAP-PREPARE HANDOVER resp. [A-HO-FA ILURE] from 3G_MS C-B MAP-PREPAREHANDOVER resp. [A-HO-REQUEST -ACK] from 3G_MSC-B Not Requested Requested I_CONNECT (IAM) to 3G_MSC-B using Handover Number W ait for Connection from 3G_MSC-B (G SM to UMTS Ho) 7 3 Figure 43 (sheet 13 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 147. Release 1999 147 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet14(78) Procedure for Handove r in 3G_MSC-A Wait For Ack nowledgement from 3G_MSC-B (G SM to UMTS Ho) ERRO R Canc el MAP Re sources from 3G_MSC-B in 3G_MSC-A Call Re lease A-CLEAR-REQUEST from BSS-A to Network From UE/MS or Network Call Release Release Resources in BSS-A Canc el MAP Resources to 3G_MS C-B IDLE 3 Figure 43 (sheet 14 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 148. Release 1999 148 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet15(78) Procedure for Handove r in 3G_MSC-A W ait for Connection from 3G_MSC-B (G SM to UMTS Ho) I_COMPLETE (ACM) from 3G_MSC-B (Allowed onc e in this state) MAP-PA S req. [A-CLEAR-REQ UEST ] from 3G_MSC-B Queue M es sages for UE/MS in 3G_MSC-A A-CLEAR-REQUEST from BSS-A Wait f or Connec tion from 3G_MSC-B (GSM to UMTS Ho) ERROR Call Releas e to UE /MS and Network Releas e Res ources in BSS-A from 3G_MS C-B or Network I_DISCONNECT (REL) to 3G_MSC-B Set T503 W ait for Comp letion on 3G_MSC-B (G SM to UMTS Ho) F rom UE /MS or Netwo rk Call Release Han dov er Command to UE/MS via B SS-A Set Up the Handov er Device (A llowed once in this s tate ) to 3G_MSC-B in 3G_MSC-A Internal mess age in 3G_MSC-A Cancel MAP Procedures I_DISCONNECT (REL) to 3G_MS C-B 3 IDLE Figure 43 (sheet 15 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 149. Release 1999 149 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet16(78) Procedure for Handove r in 3G_MSC-A W ait for Comp letion on 3G_MSC-B (G SM to UMTS Ho) MAP-S ENDEND-SIG NA L req. [A-HO-CO MP LE TE] from 3G_MSC-B Reset T503 (Allowed onc e in this state) MAP-PAS req. [A-HO-DE TECT ] from 3G_MSC-B I-ANSW ER (ANM) from 3G_MSC-B (Allowed once in this s tate) MA P-PAS re q. [A-CLEAR-REQUEST] from BSS-B A-CLEAR-REQ UEST from BSS-A Release Resourc es on BSS-A Yes Co nnect Handov er Device (option) W ait for UE/MS on 3G_MSC-B? No Wait f or Completion on 3G_MS C-B (GS M to UM TS Ho) Forward queu ed messages via 3G_MSC-B Us e M AP FORWA RD-ACCESSSIGNAL LING req Call Release to Ne twork and UE/MS Release MAP Resourc es to 3G_MSC-B in 3G_MSC-A Re lease Re sources on BSS-A Connect Handove r Device (op tio n) I_DIS CO NNECT (REL) t o 3G_MSC-B Call on 3G_MSC-B (UT RAN) IDLE Wait f or Completion on 3G_MS C-B (GS M to UM TS Ho) Figure 43 (sheet 16 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 150. Release 1999 150 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet17(78) Procedure for Handove r in 3G_MSC-A Wait f or Completion on 3G_MS C-B (GS M to UM TS Ho) I_DISCONNECT (REL) from 3 G_ MSC-B A -HANDOV ERFAILURE f rom B SS-A Res et T503 Forward q ueued me ssages for UE /MS via B SS-A Cancel MAP Procedures Call Releas e Internal to 3 G_ MSC-A Cancel MAP Procedures I_DISCONNECT (REL) to 3G_MSC-B Canc el MAP Proc edures from 3G_MSC-B Release Handover Devic e I_DISCONNECT (REL) to 3G_MSC-B Canc el MAP Proc edures In 3G _MSC-A and to 3G_MS C-B Release Handov er Device Internal to 3G_MSC-A Release Resources BSS-A I_DISCONNECT (REL) to 3G_MSC-B Call in P rogres s on 3G_MS C-A (GSM) In ternal to 3G_MSC-A Wa it for Comp letion on 3G_MS C-B (G SM to UMTS Ho) Releas e Handove r Dev ice in 3G_MSC-A to 3G_MSC-B from Network Re lease Handov er Device In 3G_MSC-A and to 3G_MSC-B Release Handover Device Expiry T5 03 W ait for Completion on 3G_MSC-B (GSM to UMTS Ho) IDLE Figure 43 (sheet 17 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 151. Release 1999 151 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet18(78) Procedure for Handove r in 3G_MSC-A Call on MSC-B (GSM) MAP-P AS req. [A-CLEARREQUEST] from 3 G_MS C-B MAP-PREPARESUB SEQUENTHANDOVER req. [A-HO-REQUEST] from MSC-B 8 Known 3G _M SC? No 3G_MSC-B' No Canc el MAP proc edures from MSC-B Call Release Whic h 3G_MSC? Call Releas e MAP-SEND-ENDS IG NAL resp. to MSC-B Call on MSC-B Yes Hand ov er allowed to Cell? Yes From UE/MS or Network to Network and UE/MS 3G_MSC-A 5 Known RNS? No Yes Res ourc es on new RNS? No I_DISCONNECT (REL) to MSC-B Yes IuRELO CATIONREQ UEST to RNS-B MAP-PRE PA RESUBSEQUENTHANDOVER res p. [MAP E RROR] to MS C-B MAP-P REPARESUBSEQUENTHANDOVER res p. [A-HO-FAILURE] to MS C-B No Set T501 Circuit Connection? Yes Wait for Channel Allocation (GS M to UM TS Ho) UE/MS o n MSC-B (GSM) Call on MSC-B (GSM) Figure 43 (sheet 18 of 78): Handover control procedure in 3G_MSC-A 3GPP IDLE
  • 152. Release 1999 152 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet19(78) Procedure for Handove r in 3G_MSC-A Wait for Channel Allocation (GS M to UMT S Ho) IuRELOCATIO N FAILURE from RNS-B Iu-RELOCATION REQUEST -ACK. from RNS-B (Allowed once in this state) MAP-PAS req. [A -CLEAR-REQUE ST ] from MS C-B Release Resources in RNS-B MAP-PREPARE SUBSEQ UENTHANDOV ER resp [A-HO -REQUESTACK] t o MSC-B No Circuit Connect ion? Call Re lease MAP-SEND-ENDSIGNAL resp to MS C-B Release Resourc es in RNS-B I_DISCONNE CT (REL) to MSC-B Call o n MSC-B Yes Se t Up Handove r Dev ice Set T504 MAP-PREPARESUBSEQUENTHA NDOVER resp. [A-HO-FAILURE] to MSC-B Call on MSC-B (GSM) Wait for Acces s by UE /MS (GS M to UMT S Ho) IDLE Figure 43 (sheet 19 of 78): Handover control procedure in 3G_MSC-A 3GPP From UE/MS or Network Ca nc el Channel RNS-B Reset T 501 Res et T501 Queue Mess ages for UE/MS in 3G_MSC-A Expiry T5 01
  • 153. Release 1999 153 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet20(78) Procedure for Handove r in 3G_MSC-A Wa it f or acces s by UE /MS (G SM to UMTS Ho) Iu-RE LO CAT ION DET ECT from RNS-B Iu-RELOCATION COMPLE TE from RNS-B No Res et T504 Expiry T504 Call Release Circuit Connection? to Network Yes Release Resources on RNS-B Connec t Handover Device (option) Connect Han dov er Device (o ption) Forward queued messages for MS via RNS-B Canc el MAP Proc edures MA P-SEND-ENDSIGNAL resp. to MSC-B No in 3G_MSC-A to MS C-B I _DISCONNECT (RE L) to MSC-B Circuit Con nec tion? Yes Releas e Han dov er Dev ice I_DISCONNECT (REL) to MSC-B Call in P rogres s on 3G_MS C-A (UTRAN) W ait for access by UE/MS (GSM to UMT S Ho) IDLE Figure 43 (sheet 20 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 154. Release 1999 154 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet21(78) Procedure for Handove r in 3G_MSC-A W ait for acces s by UE/MS (G SM to UMTS Ho) MAP-PAS req. [A-HOFAILURE] from MSC-B Iu -RELEASE REQUEST from RNS-B Forward queu ed messages via MS C-B MAP-PAS req. [A-CLE ARREQUEST ] from MSC-B (Allowed once in this state) Canc el MAP Proc edures fro m Network Call Releas e (Allowed once in this state) Us e MAP -FORW ARDACCESS-SIGNALLING req. Re lease Re sources on RNS-B Circu it Connec tion? No Yes Re lease Handov er Device Call on MS C-B (G SM ) UE /MS on MSC-B (GSM) Wait for acces s by UE /MS (GS M to UMT S Ho) Figure 43 (sheet 21 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 155. Release 1999 155 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Procedure for Handove r in 3G_MSC-A Sheet22(78) Sub sequent GSM to UMT S Handover from MSC-B to 3G _MSC-B' Circ uit Connection required 5 MAP-PREPARE-HANDOVER req [A-HO-REQ UEST ] to 3G _MSC-B' W ait for Ack from 3G_MSC-B' (G SM to UMTS Ho) MAP-PRE PA REHANDOVER res p. [A-HO-FAILURE] from 3G_MSC-B ' MAP-P REPAREH ANDOVER res p.. [A-HO-RE QUES T-A CK] from 3G_MSC-B' Handov er Number? Not Requested Requested MAP-P REPARESUBSEQUENTHA NDOVER res p. [A-HO-FAILURE] to MSC-B I_CONNECT (IAM) to 3G_MS C-B' using Han dov er Number W ait for Connection from 3G_MSC-B' (G SM to UMTS Ho) Call on MSC-B (GSM) 9 Figure 43 (sheet 22 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 156. Release 1999 156 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet23(78) Procedure for Handove r in 3G_MSC-A W ait for Ack from 3G_MSC-B' (G SM to UMTS Ho) ERRO R Re lease MAP Re sources from 3G_MSC-B' f rom MS C-B o r Network ERRO R Call Release Canc el MAP Proc edures to 3G _MSC-B' MAP-PAS req. [A-CLEAR-REQUEST] from 3G_MSC-B Call on MS C-B (G SM ) to 3G _MSC-B' MAP-S ENDEND-SIGNA L resp. to MS C-B Cancel MAP Procedures ERRO R From UE/MS or Network to 3G_MSC-B' Release Handov er Devic e MAP-P REPARESUBSEQUENTHA NDOVER res p. to MS C-B I_DISCONNECT (REL) to MSC-B W ait for Ac k from 3G _MSC-B' (GSM to UMTS Ho) IDLE Figure 43 (sheet 23 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 157. Release 1999 157 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet24(78) Procedure for Handove r in 3G_MSC-A W ait for Connection from 3G_MSC-B' (G SM to UMTS Ho) I_ COMPLETE (ACM) from 3G _MSC-B' Set up Handov er Device from 3G_MSC-B' or Network from UE/MS or Network ERRO R (Allowed once in this state) MAP-P AS req. [A-CLEARREQUEST] from 3G_ MSC-B ' Call Releas e MAP-PA S req. [A-CLEARREQ UEST ] from MSC-B W ait f or Connection f rom 3G _MSC-B' (GSM to UMT S Ho) MAP-P REPARESUBSEQUENTHA NDOVER res p. [A-HO-RE QUES T-A CK] to MS C-B to 3G _MSC-B' Cancel MAP Procedures Queue m es sages for UE/MS in 3G_MSC-A to 3G_MSC-B' Canc el MAP Proc edures W ait for Comp letion on 3G _MSC-B' (G SM to UMTS Ho) E RROR M AP -PREPARES UBS EQ UE NTHANDO VER resp. to MSC-B to MS C-B and 3G _MSC-B' MAP -SENDE ND-SIGNAL res p to MSC-B I_ DISCONNECT (RE L) to 3G_MSC-B' Call Release Set T503 Cancel MAP Procedures to Network and UE /MS I_DISCO NNECT (REL) to MSC-B and 3G _MSC-B' Call o n MSC-B (GSM) IDLE Figure 43 (sheet 24 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 158. Release 1999 158 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet25(78) Procedure for Handove r in 3G_MSC-A W ait for Comp letion on 3G _MSC-B' (G SM to UMTS Ho) Reset T503 I_ANSWER (ANM) from 3G_MSC-B ' MAP-PA S req. [A-CLEARREQ UE ST] from MSC-B MAP-P AS req. [A-HO-DET ECT] from 3G _MSC-B' MAP-S ENDEND-SIG NA L req. [A-HO-CO MP LE TE] from 3G_MSC-B' MA P-PAS req. [A -CLEARREQUEST ] from 3G_MSC-B' (A llowed once in this s tate) Yes Connec t Handover Device (option) Co nnect Handov er Device (option) (Allowed onc e in this state) Wait for ac cess by UE/ MS? No Forward queu ed messages for U E/MS v ia 3G_MSC-B' Releas e Handove r D ev ice Us e MAP -FORW ARDACCESS-SIGNALLING req. MAP-S ENDEND-SIG NA L resp. to MS C-B to MS C-B and 3G _MSC-B' to Network and UE/MS I_DISCONNE CT (REL) to MSC-B Redefine 3G_MSC-B' as 3G_MSC-B Call on 3G_MSC-B (UT RAN) Cancel MAP Procedures Call Releas e I_DISCO NNECT (REL ) to MSC-B and 3G _MSC-B' W ait for Completion from 3G _MSC-B' (GSM to UMTS Ho) Figure 43 (sheet 25 of 78): Handover control procedure in 3G_MSC-A 3GPP IDLE
  • 159. Release 1999 159 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet26(78) Procedure for Handove r in 3G_MSC-A W ait for Comp letion on 3G _MSC-B' (G SM to UMTS Ho) MA P-PAS re q. [A-HO-FAILURE] from MSC-B Expiry T503 Res et T503 Ca nc el MAP Proc edures from MSC-B Canc el MAP Proc edures from 3G_MSC-B' Cancel MAP Procedures Call Releas e I_DISCONNECT (REL) to 3G_ MSC-B ' Release Handover Devic e I_DISCONNECT (REL) to MSC-B to 3G _MSC-B' From Network or MSC-B Releas e Handover Device Release Handov er Device W ait for acc ess by UE/MS? I_ DISCONNECT (REL) to 3G_MSC-B ' Yes No MSC-B Connec tion? Yes Cancel MAP Procedures to 3G_MSC-B' No Use MAPFORW ARDACCE SS SIGNALLING req. Call Re lease IDLE Forward queued mes sages for UE/MS via MSC-B I_DISCONNECT (REL) to 3G _MSC-B' to Netwo rk Call on MSC-B (GSM) IDLE Figure 43 (sheet 26 of 78): Handover control procedure in 3G_MSC-A 3GPP Wait f or Co mpletion on 3G _MSC-B ' (GS M to UMT S Ho)
  • 160. Release 1999 160 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet27(78) Procedure for Handove r in 3G_MSC-A Bas ic GS M to UMT S Handov er to 3G_MSC-B no Circuit Connection requ ired 7 Queue M es sages for UE/MS in 3G_MSC-A Han dov er Command to UE/MS via B SS-A Set T503 W ait for UE/MS on 3G_MSC-B (G SM to UMTS Ho) (Allowed once in this state) MAP-S ENDEND-SIG NA L req. [A-HO-CO MP LE TE] from 3G_MSC-B Reset T503 (Allowed once in this state) MAP-PA S req. [A-CLEARREQ UE ST ] from 3G_MSC-B Yes Re lease Re sources on BSS-A Forward queu ed messages for UE/MS via 3G_MSC-B UE/MS on 3G_MSC-B (UT RAN) A-CLE ARREQUEST from BS S-A MAP-PAS req. [A-HO-DE TECT ] from 3G_MSC-B Release Resourc es on BSS-A W ait for UE/MS on 3G_MSC-B? No W ait for UE/MS o n 3G_MSC-B (GSM to UMT S Ho) Call Release to Network and UE/MS Release MAP Resourc es Us e M AP FORWA RD-ACCESSSIGNALLING req. to 3G_MSC-B in 3G_MSC-A IDLE W ait for UE/MS on 3G_MSC-B (G SM to UMTS Ho) Figure 43 (sheet 27 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 161. Release 1999 161 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet28(78) Procedure for Handove r in 3G_MSC-A Wait for UE/MS on 3G_MS C-B (GS M to UM TS Ho) Cancel MAP Procedures A -HANDOV ERFAILURE f rom B SS-A In 3G _MSC-A and to 3G_MS C-B Res et T503 Forward q ueued me ssages for UE /MS via B SS-A in 3G_MSC-A to 3G_MSC-B from 3 G_ MSC-B Expiry T 503 Call Re lease from Network Canc el MAP Proc edures Release Resourc es BS S-A Release Reso urces BSS-A Cancel MAP Procedures Call in P rogres s on 3G_MS C-A (GSM) Wait for UE /MS on 3G_MSC-B (GSM to UMTS Ho) IDLE W ait for UE/MS on 3G_MSC-B (G SM to UMTS Ho) Figure 43 (sheet 28 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 162. Release 1999 162 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Procedure for Handove r in 3G_MSC-A Sheet29(78) UE/MS Es tablished on M SC-B without a Circ uit Connec tion UE /MS on MSC-B (GSM) Reque st for Circ uit Es tablishment F rom MSC-B M AP -PREPARES UBS EQ UE NTHANDO VER req. [A-HO-REQUEST] from MS C-B Canc el MAP Proc edures Call Release From UE/MS or Network Call Releas e to Network MAP-SEND-ENDS IG NAL resp. to MSC-B MAPPREPAREHANDOVER re q. [NUL L] [A-ASGR EQ UE ST ] to MSC-B Wait F or Response from MSC-B (UMTS to GSM Ho) 8 IDLE Figure 43 (sheet 29 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 163. Release 1999 163 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Procedure for Handove r in 3G_MSC-A Sheet30(78) Circ uit Connection E stablis hme nt to 3G_MS C-B W ait For Response from 3G_MSC-B (G SM to UMTS Ho) MAP-P REPAREH ANDOVER res p. [Handover Number] [A -ASG-CO MPLE TE] from 3G_MSC-B Call Release MAP-SENDEND-SIGNAL res p. to 3G_MSC-B I_CONNECT (IAM) to 3G _MSC-B using Han dov er Number W ait for Comp lete from 3G_MSC-B (G SM to UMTS Ho) F rom UE/MS or Network IDLE Figure 43 (sheet 30 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 164. Release 1999 164 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet31(78) Procedure for Handove r in 3G_MSC-A W ait For Response from 3G_MSC-B (G SM to UMTS Ho) MAP-P REPAREH ANDOVER res p. [M AP ERROR] from 3G_MSC-B MAP -PREPAREHANDOVER resp. [A-ASG-FAILURE] from 3G_MS C-B MA P-PAS re q. [A-CLEAR-REQUEST] from 3G_MSC-B Failure Cance l MAP Proce dures (A llowed once in this s tate ) Res po nse to Circ uit Establishment Request Call Re lease Failure UE/MS on 3G_MSC-B (UTRAN) UE/MS on 3 G_MS C-B (UT RAN) IDLE Figure 43 (sheet 31 of 78): Handover control procedure in 3G_MSC-A 3GPP from 3G_MSC-B to Netwo rk Res po nse to Circuit Establishment Request
  • 165. Release 1999 165 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet32(78) Procedure for Handove r in 3G_MSC-A W ait for Comp lete from 3G_MSC-B (G SM to UMTS Ho) I_COM PLE TE (ACM) from 3G_MSC-B MAP-PAS req. [A -CLEARREQ UEST ] from 3G_MSC-B (Allowed once in this state) Call Re lease From UE/MS or Network I-ANSW ER (ANM) from 3G_MSC-B from 3G_MSC-B Succes s W ait for Comp lete from 3G_MSC-B (G SM to UMTS Ho) Respons e to Circu it E stablis hme nt Request Res po nse to Circ uit Establishment Request Call on 3G_MS C-B (UTRAN) Canc el MAP Proc edures MAP-S ENDEND-SIGNAL res p. to 3G_MSC-B I_DISCONNECT (REL) to 3G_MSC-B Failure IDLE Figure 43 (sheet 32 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 166. Release 1999 166 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Procedure for Handove r in 3G_MSC-A Sheet33(78) Sub sequent GSM to UMT S Handover from MSC-B to 3G_ MSC-B' no Circuit Connection requ ired. 9 MAP-P REPARESUBSEQUENTHA NDOVER res p. [A-HO-RE QUES T-A CK] to 3G_MS C-B Queue M es sages for UE/MS in 3G_MSC-A Set T503 W ait for UE/MS on 3G _MSC-B' (G SM to UMTS Ho) Reset T503 Forward queu ed messages for UE/MS via 3G _MSC-B' MAP-P AS req. [A-CLEARREQUEST] from 3G_ MSC-B ' Yes (Allowed once in this state) W ait for acc es s by UE/MS? No Us e M AP FORWA RD-ACCESSSIGNAL LING req to 3G_MSC-B and 3G_MSC-B' Redefine 3G_MSC-B' as 3G_MSC-B UE/MS on 3G_MSC-B (UT RAN) (Allowed once in this st ate) MAP-P AS req. [A-HO -DETECT] from 3G _MSC-B' MAP-S ENDEND-SIGNAL req [A-HO-CO MP LE TE] from 3G_MSC-B' to Network and UE/MS W ait for UE/MS on 3G_MSC-B' (GSM to UMTS Ho) Canc el MAP Proc edures Call Re lease IDLE Figure 43 (sheet 33 of 78): Handover control procedure in 3G_MSC-A 3GPP MAP-PAS req. [A -CLEARREQ UEST ] from MSC-B
  • 167. Release 1999 167 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet34(78) Procedure for Handove r in 3G_MSC-A W ait for UE/MS on 3G _MSC-B' (G SM to UMTS Ho) MA P-PAS re q. [A-HOFAILURE] from MSC-B Expiry T503 Res et T503 Forward queu ed messages for UE/MS via MS C-B Ca nc el MAP Proc edures UE/MS on MS C-B (G SM ) from MSC-B Canc el MAP Proc edures Call Releas e Can cel MAP Procedures Yes W ait for acc ess by UE/MS? Us e M AP FORW ARDACCESSSIGNALLING req. to 3G _MSC-B' from 3G_MSC-B' No to 3G_MSC-B ' Cancel MAP Procedures IDLE Wa it for UE/MS on 3G _MSC-B' (G SM to UMTS Ho) Figure 43 (sheet 34 of 78): Handover control procedure in 3G_MSC-A 3GPP from Network or MSC-B
  • 168. Release 1999 168 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Procedure for Handove r in 3G_MSC-A Sheet35(78) Basic UMTS to GSM Hand over to MS C-B Crcuit Connec tion required 14 MAP-P REPAREHA NDOVER req. [A-HO-REQ UEST ] to MS C-B Wait For Ack nowledgement from MSC-B (UMTS to GSM Ho) Handover Number? MAP-P REPAREHA NDOVER res p. [MAP ERROR] from MSC-B MAP-PREPARE HANDOVER resp. [A-HO-FA ILURE] from MSC-B MAP-PREPAREHANDOVER es p. [A-HO-REQUEST -ACK] from MSC-B Not Requested Requested I_CONNECT (IAM) to MSC-B us ing Handover Number W ait for Connection from MSC-B (UMTS to GSM Ho) 12 18 Figure 43 (sheet 35 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 169. Release 1999 169 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet36(78) Procedure for Handove r in 3G_MSC-A Wait For Ack nowledgement from MSC-B (UMTS to GSM Ho) ERRO R Canc el MAP Re sources from MSC-B in 3G_MSC-A Call Re lease Iu-RELEASE-REQ UE ST from RNS-A to Network From UE/MS or Network Call Release Release Resources in RNS-A Canc el MAP Resources to MS C-B IDLE 12 Figure 43 (sheet 36 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 170. Release 1999 170 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet37(78) Procedure for Handove r in 3G_MSC-A W ait for Connection from MSC-B (UMTS to GSM Ho) I_COM PLE TE (ACM) from MSC-B MAP-PA S req. [A-CLEAR-REQ UEST ] from MSC-B Queue M es sages for UE/MS in 3G_MSC-A Iu-RELEASE-REQ UE ST from RNS-A (Allowed onc e in this state) Wait f or Connec tion from MSC-B (UMTS to GSM Ho) Call Release ERROR Iu-Relocation Command to RNS-A W ait for Comp letion on MS C-B (UMTS to GSM Ho) F rom UE /MS or Netwo rk Call Releas e to UE /MS and Network Releas e Res ources in RNS-A from MSC-B or Network I_DISCONNECT (REL) to MS C-B Set T303 Set Up the Handov er Device (A llowed once in this s tate ) to MSC-B in 3G_MSC-A Internal mess age in 3G_MSC-A Cancel MAP Procedures I_DISCONNECT (RE L) to MSC-B 12 Figure 43 (sheet 37 of 78): Handover control procedure in 3G_MSC-A 3GPP IDLE
  • 171. Release 1999 171 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet38(78) Procedure for Handove r in 3G_MSC-A W ait for Comp letion on MS C-B (UMTS to GSM Ho) MAP-S ENDEND-SIG NA L req. [A-HO-CO MP LE TE] from MSC-B (Allowed onc e in this state) Reset T303 MAP-PAS req. [A-HO-DE TECT ] from MSC-B I-ANSW ER (ANM) from MSC-B (Allowed once in this s tate) MA P-PAS re q. [A-CLEAR-REQUEST] from MSC-B Iu-RELEASE-REQ UE ST from RNS-A Release Resourc es on RNS-A Yes Co nnect Handov er Device (option) W ait for UE/MS on MSC-B? No Wait f or Completion on MSC-B (UMTS to GSM Ho) Forward queu ed messages via MS C-B Us e M AP FORWA RD-ACCESSSIGNAL LING req Call Release to Ne twork and UE/MS Release MAP Resourc es to MSC-B in 3G_MSC-A Connect Handove r Device (op tio n) I_DIS CO NNECT (REL) to MS C-B Release Resources on RNS-A Call on MS C-B (G SM ) IDLE Wait f or Completion on MSC-B (UMTS to GSM Ho) Figure 43 (sheet 38 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 172. Release 1999 172 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet39(78) Procedure for Handove r in 3G_MSC-A Wait f or Completion on MSC-B (UMTS to GSM Ho) IuRELO CATIONCANCE L from RNS-A Expiry T3 03 I_DISCONNECT (RE L) from MSC-B Res et T303 Forward q ueued me ssages for UE/MS via RNS-A Cancel MAP Procedures Internal to 3 G_ MSC-A Cancel MAP Procedures I_DISCONNECT (REL) to MSC-B Canc el MAP Proc edures f rom MS C-B Release Handover Devic e I_DISCONNECT (REL) to MSC-B Canc el MAP Proc edures In 3G _MSC-A and to MS C-B Release Handov er Device Internal to 3G_MSC-A Release Resources RNS-A I_DISCONNE CT (REL) to MSC-B Call in P rogres s on 3G_MS C-A (UT RAN) In ternal to 3G_MSC-A Wa it for Comp letion on MS C-B (UMTS to GSM Ho) Releas e Handove r Dev ice in 3G_MSC-A to MSC-B from Network Re lease Handov er Device In 3G_MSC-A and to MSC-B Release Handover Device Call Releas e W ait for Completion on MSC-B (UMTS to GS M Ho) IDLE Figure 43 (sheet 39 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 173. Release 1999 173 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet40(78) Procedure for Handove r in 3G_MSC-A Call on 3G_MS C-B (UT RAN) MAP-P AS req. [A-CLEARREQUEST] from 3 G_MS C-B MAP-PREPARESUB SEQUENTHANDOVER req. [A-HO-REQUEST] from 3G_MSC-B 19 No Known MSC? Call on 3G_MSC-B (UTRAN) Yes No Canc el MAP proc edures Whic h MSC? Call Releas e MAP-SEND-ENDS IG NAL resp. to 3G_MSC-B from 3G_MSC-B Call Release Hand ov er allowed to Cell? Yes MSC-B ' From UE/MS or Network to Network and UE/MS 3G_MSC-A 20 Known BSS? No Yes Res ourc es on new BSS? No I_DISCONNECT (RE L) to 3G_MS C-B Yes A -HANDOV ERREQ UEST to BSS-B MAP-PRE PA RESUBSEQUENTHANDOVER res p. [MAP E RROR] to 3G_MSC-B MAP-P REPARESUBSEQUENTHANDOVER res p. [A-HO-FAILURE] to 3G_MS C-B No Set T301 Circuit Connection? Yes Wait for Channel Allocation (UMTS to GSM Ho) UE/MS o n 3G_MSC-B (UTRAN) Call on 3G_MSC-B (UTRAN) Figure 43 (sheet 40 of 78): Handover control procedure in 3G_MSC-A 3GPP IDLE
  • 174. Release 1999 174 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet41(78) Procedure for Handove r in 3G_MSC-A Wait for Channel Allocation (UMTS to GSM Ho) AHANDOVERFAILURE from BSS-B A-HANDOV ERREQUEST -ACK. from B SS-B (Allowed onc e in this state) MAP-PAS req. [A -CLEAR-REQUE ST] from 3G_MSC-B Release Reso urces in BSS-B MAP-PRE PA RESUBSEQUENTHANDOV ER res p [A-HO REQUEST-ACK] to 3G_MSC-B No Circuit Conn ec tion? Call Re lease From UE/MS or Network Canc el Channel BSS-B Reset T 301 Res et T301 Queue Mess ages for UE /MS in 3G_MSC-A Expiry T 301 MAP-SEND-ENDSIGNAL resp to 3G_MS C-B Release Resourc es in BS S-B I_DISCONNECT (REL) to 3G_MSC-B Call on 3G_MSC-B (UTRAN) Yes Set Up Handove r Dev ice Set T304 MAP-P REPARESUBSEQUENTHA NDOVER res p. [A-HO-FAILURE] to 3G_MS C-B Call on 3G_MSC-B (UTRAN) Wait for Acces s by UE /MS (UMTS to GSM Ho) IDLE Figure 43 (sheet 41 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 175. Release 1999 175 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet42(78) Procedure for Handove r in 3G_MSC-A Wa it f or acces s by UE /MS (UMTS to GSM Ho) A-HANDOVER DET ECT from BS S-B A-HANDOVERCOMPLE TE from BSS-B No Res et T304 Expiry T304 Call Release Circuit Connection? to Network Yes Release Resources on BSS-B Connec t Handover Device (option) Connect Han dov er Dev ice (option) Forward queued messages for UE /MS v ia BSS-B Canc el MAP Proc edures MA P-SEND-ENDSIGNAL resp. to 3G_MS C-B No in 3G_MSC-A to 3G_MS C-B I_ DISCONNECT (RE L) to 3G_MSC-B Circuit Con nec tion? Yes Releas e Han dov er Dev ice I_DISCONNECT (REL) to 3G_MSC-B Call in P rogres s on 3G_MS C-A (G SM ) W ait for access by UE/MS (UMTS to GSM Ho) IDLE Figure 43 (sheet 42 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 176. Release 1999 176 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet43(78) Procedure for Handove r in 3G_MSC-A W ait for acces s by UE/MS (UMTS to GSM Ho) MAP-PAS req. [A-HOFAILURE] from 3G_MSC-B MAP-PAS req. [A -CLEARRE QUES T] from 3G_MSC-B A-CLEARREQUEST from BSS-B Forward queu ed messages via 3G_MSC-B (Allowed once in this state) Canc el MAP Proc edures fro m Network Call Releas e (Allowed once in this state) Us e MAP -FORW ARDACCESS-SIGNALLING req. Re lease Re sources on BSS-B Circu it Connec tion? No Yes Re lease Handov er Device Call on 3G_MSC-B (UT RAN) UE /MS on 3G_MS C-B (UT RAN) Wait for acces s by UE /MS (UMTS to GSM Ho) Figure 43 (sheet 43 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 177. Release 1999 177 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Procedure for Handove r in 3G_MSC-A Sheet44(78) Sub sequent UMTS to GSM Handover from 3G_MSC-B to MSC-B' Circ uit Connection required 20 MAP-PREPARE-HANDOVER req [A-HO-REQ UEST ] to MSC-B' W ait for Ack from MSC-B' (UMTS to GSM Ho) MAP-PRE PA REHANDOVER res p. [A-HO-FAILURE] from MSC-B' MAP-P REPAREH ANDOVER res p.. [A-HO-RE QUES T-A CK] from MSC-B' Handov er Number? Not Requested Requested MAP-P REPARESUBSEQUENTHA NDOVER res p. [A-HO-FAILURE] to 3G_MS C-B I_CONNECT (IAM) to MS C-B' using Han dov er Number W ait for Connection from MSC-B' (UMTS to GSM Ho) Call on 3G_MSC-B (UTRAN) 21 Figure 43 (sheet 44 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 178. Release 1999 178 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet45(78) Procedure for Handove r in 3G_MSC-A W ait for Ack from MSC-B' (UMTS to GSM Ho) ERRO R Re lease MAP Re sources from MSC-B' from 3G_MSC-B or Network ERRO R Call Release Canc el MAP Proc edures to MSC-B' MAP-PAS req. [A-CLEAR-REQUEST] from 3G_MSC-B Call on 3G_MSC-B (UT RAN) to MSC-B' MAP-S ENDEND-SIGNA L resp. to 3G_MS C-B Cancel MAP Procedures ERRO R From UE/MS or Network to MSC-B' Release Handov er Devic e MAP-P REPARESUBSEQUENTHA NDOVER res p. to 3G_MS C-B I_DISCONNECT (REL) to 3G_MSC-B W ait for Ac k from MSC-B' (UMTS to GSM Ho) IDLE Figure 43 (sheet 45 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 179. Release 1999 179 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet46(78) Procedure for Handove r in 3G_MSC-A W ait for Connection from MSC-B' (UMTS to GSM Ho) I_ COMPLETE (ACM) from MSC-B' Set up Handov er Device from MS C-B' or Network from UE/MS or Network ERRO R (Allowed once in this state) MAP-PAS req. [A -CLEARREQ UEST ] from MSC-B' Call Releas e MAP-PA S req. [A-CLEARREQ UEST ] from 3G_MSC-B W ait f or Connection f rom MSC-B' (UMTS to GSM Ho) MAP-P REPARESUBSEQUENTHA NDOVER res p. [A-HO-RE QUES T-A CK] to 3G_MS C-B to MSC-B' Cancel MAP Procedures Queue m es sages for UE/MS in 3G_MSC-A to MSC-B' Canc el MAP Proc edures W ait for Comp letion on MSC-B' (UMTS to GSM Ho) E RROR M AP -PREPARES UBS EQ UE NTHANDO VER resp. to 3G_MSC-B to 3G_MSC-B and MSC-B' MAP -SENDE ND-SIGNAL res p to 3G_MSC-B I_ DISCONNECT (RE L) to MSC-B' Call Release Set T303 Cancel MAP Procedures to Network and UE /MS I_DISCO NNECT (REL) to 3G_MSC-B and MSC-B' Call o n 3G_MSC-B (UTRAN) IDLE Figure 43 (sheet 46 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 180. Release 1999 180 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet47(78) Procedure for Handove r in 3G_MSC-A W ait for Comp letion on MSC-B' (UMTS to GSM Ho) Reset T303 MAP-P AS req. [A-CLEARREQUEST] from 3G_MS C-B MAP-P AS req. [A-HO-DET ECT] from MSC-B ' MAP-S ENDEND-SIG NA L req. [A-HO-CO MP LE TE] from MSC-B' MAP-P AS req. [A-CLEARREQUEST] from MSC-B' I_ANSWER (ANM) from MSC-B' (A llowed once in this s tate) Yes Connec t Handover Device (option) Co nnect Handov er Device (option) (Allowed onc e in this state) Wait for access by UE/MS? No Forward queu ed messages for U E/MS v ia MSC-B' Releas e Handove r D ev ice Us e MAP -FORW ARDACCESS-SIGNALLING req. MAP-S ENDEND-SIG NA L resp. to 3G_MS C-B to 3G_MSC-B and MSC-B' Cancel MAP Procedures I_DISCONNE CT (REL) to 3G_MSC-B to Network and UE/MS Call Releas e I_DISCO NNECT (REL ) to 3G_MSC-B and MSC-B' Redefine MSC-B' as MSC-B Call on MS C-B (G SM ) W ait for Completion from MSC-B' (UMTS to GSM Ho) Figure 43 (sheet 47 of 78): Handover control procedure in 3G_MSC-A 3GPP IDLE
  • 181. Release 1999 181 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet48(78) Procedure for Handove r in 3G_MSC-A W ait for Comp letion on MSC-B' (UMTS to GSM Ho) MA P-PAS re q. [A-HO-FAILURE] from 3G_MSC-B Expiry T303 Res et T303 Ca nc el MAP Proc edures from 3G_MSC-B to MSC-B' Canc el MAP Proc edures from MSC-B' Cancel MAP Procedures I_DISCONNECT (REL) to 3 G_ MSC-B From Network or 3G_MSC-B Call Releas e I_DISCONNECT (REL) to MSC-B ' Release Handover Devic e Releas e Handover Device Release Handov er Device W ait for acc ess by UE/MS? I_ DISCONNECT (REL) to MSC-B' Yes No 3G_MSC-B Connec tion? Yes Cancel MAP Procedures to MSC-B' No Use MAPFORW ARDACCE SS SIGNALLING req. Call Re lease IDLE Forward queued mes sages for UE/MS via 3G_MSC-B I_DISCONNECT (REL) to MSC-B' to Netwo rk Call on 3G_MSC-B (UTRAN) IDLE Figure 43 (sheet 48 of 78): Handover control procedure in 3G_MSC-A 3GPP Wait f or Co mpletion on MSC-B ' (UMTS to GSM Ho)
  • 182. Release 1999 182 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet49(78) Procedure for Handove r in 3G_MSC-A Basic UMTS to GSM Hand over to MS C-B no Circuit Connection requ ired 18 Queue M es sages for UE/MS in 3G_MSC-A Iu-Relocation Command to RNS-A Set T303 W ait for UE/MS on MS C-B (UMTS to GSM Ho) (Allowed once in this state) MAP-S ENDEND-SIG NA L req. [A-HO-CO MP LE TE] from MSC-B Reset T303 (Allowed once in this state) MAP-PAS req. [A -CLEARREQ UEST ] from MSC-B Yes Re lease Re sources on RNS-A MAP-PAS req. [A-HO-DE TECT ] from MSC-B Iu-RE LEA SE REQUEST from RNS-A Release Resourc es on RNS-A W ait for UE/MS on MSC-B? No UE/MS on MS C-B (G SM ) Us e M AP FORWA RD-ACCESSSIGNALLING req. W ait for UE/MS o n MSC-B (UMTS to GSM Ho) Call Release to Network and UE/MS Release MAP Resourc es Forward queu ed messages for UE/MS via MS C-B to MSC-B in 3G_MSC-A IDLE W ait for UE/MS on MS C-B (UMTS to GSM Ho) Figure 43 (sheet 49 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 183. Release 1999 183 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet50(78) Procedure for Handove r in 3G_MSC-A Wait for UE /MS on MSC-B (UMTS to GSM Ho) Cancel MAP Procedures Iu-RELO CATIONCANCEL from RNS-A Res et T303 Forward queued mes sages for UE/MS via RNS-A in 3G_MSC-A to MS C-B from MS C-B In 3G _MSC-A and to MSC-B Release Resources RNS-A Expiry T3 03 Call Re lease Canc el MAP Proc edures Release Resourc es RNS-A Cancel MAP Procedures Call in P rogress on 3 G_MS C-A (UT RAN) W ait for UE/MS o n MSC-B (UMTS to GSM Ho) IDLE W ait for UE/MS on MS C-B (UMTS to GSM Ho) Figure 43 (sheet 50 of 78): Handover control procedure in 3G_MSC-A 3GPP from Network
  • 184. Release 1999 184 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Procedure for Handove r in 3G_MSC-A Sheet51(78) UE/MS Es tablished on 3G_MSC-B without a Circ uit Connec tion UE /MS on 3G_MSC-B Reque st for Circ uit Es tablishment From 3G_MS C-B M AP -PREPARES UBS EQ UE NTHANDO VER req. [A-HO-REQUEST] from 3G_MSC-B Canc el MAP Proc edures Call Release From UE/MS or Network Call Releas e to Network MAP-SEND-ENDS IG NAL resp. to 3G_MSC-B MAPPREPAREHANDOVER re q. [NULL] [A-ASGR EQ UE ST ] to 3G_MSC-B Wait F or Response from 3G_MSC-B (GS M to UM TS Ho) 19 IDLE Figure 43 (sheet 51 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 185. Release 1999 185 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Procedure for Handove r in 3G_MSC-A Sheet52(78) Circ uit Connection Es tablis hment to MS C-B W ait For Response from MSC-B (UMTS to GSM Ho) MAP-P REPAREH ANDOVER res p. [Handover Number] [A -ASG-CO MPLE TE] from MSC-B Call Release MAP-SENDEND-SIGNAL res p. to MSC-B I_CONNECT (IAM) to MS C-B us ing Han dov er Number W ait for Comp lete from MSC-B (UMTS to GSM Ho) F rom UE/MS or Network IDLE Figure 43 (sheet 52 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 186. Release 1999 186 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet53(78) Procedure for Handove r in 3G_MSC-A W ait For Response from MSC-B (UMTS to GSM Ho) MAP-P REPAREH ANDOVER res p. [M AP ERROR] from MSC-B MA P-PAS re q. [A-CLEAR-REQUEST] from MSC-B Failure Cance l MAP Proce dures MAP -PREPAREHANDOVER resp. [A-ASG-FAILURE] from MS C-B (A llowed once in this s tate ) Res po nse to Circ uit Establishment Request Call Re lease Failure UE/MS on MSC-B (GSM) UE/MS on MSC-B (GSM) IDLE Figure 43 (sheet 53 of 78): Handover control procedure in 3G_MSC-A 3GPP from MSC-B to Netwo rk Res po nse to Circuit Establishment Request
  • 187. Release 1999 187 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet54(78) Procedure for Handove r in 3G_MSC-A W ait for Comp lete from MSC-B (UMTS to GSM Ho) I_COM PLE TE (ACM) from MSC-B MAP-PAS req. [A-CLE ARREQUEST] from MSC-B (Allowed once in this state) Call Re lease From UE/MS or Network I-ANSW ER (ANM) from MSC-B from MS C-B Succes s W ait for Comp lete from MSC-B (UMTS to GSM Ho) Respons e to Circuit E stablis hment Request Res po nse to Circuit Establishment Request Call on MSC-B (GSM) Canc el MAP Proc edures MAP-S ENDEND-SIGNAL res p. to MSC-B I_DISCONNECT (REL) to MSC-B Failure IDLE Figure 43 (sheet 54 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 188. Release 1999 188 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Procedure for Handove r in 3G_MSC-A Sheet55(78) Sub sequent UMTS to GSM Handov er from 3G_MSC-B to MS C-B' no Circuit Connection requ ired. 21 MAP-P REPARESUBSEQUENTHA NDOVER res p. [A-HO-RE QUES T-A CK] to 3G_MS C-B Queue M es sages for UE/MS in 3G_MSC-A Set T303 W ait for UE/MS on MSC-B' (UMTS to GSM Ho) MAP-P AS req. [A-HO -DETECT] from MSC-B ' MAP-S ENDEND-SIGNAL req [A-HO-CO MP LE TE] from MSC-B' Reset T303 Forward queu ed messages for U E/MS v ia MSC-B' MAP-PAS req. [A -CLEARREQ UEST ] from MSC-B' Yes (Allowed once in this state) W ait for acces s by UE/MS? No Us e M AP FORWA RD-ACCESSSIGNAL LING req to 3G_MSC-B and MSC-B' W ait for UE/MS on MSC-B' (UMT S to GS M Ho) Canc el MAP Proc edures to Network and UE/MS Redefine MSC-B' as MSC-B UE/MS on MS C-B (G SM ) (Allowed once in this st ate) Call Re lease IDLE Figure 43 (sheet 55 of 78): Handover control procedure in 3G_MSC-A 3GPP MAP-PAS req. [A -CLEARREQ UEST ] from 3G_MSC-B
  • 189. Release 1999 189 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet56(78) Procedure for Handove r in 3G_MSC-A W ait for UE/MS on MSC-B' (UMTS to GSM Ho) MA P-PAS re q. [A-HOFAILURE] from 3G_MSC-B Expiry T303 Res et T303 Forward queu ed messages for UE/MS via 3G_MSC-B Us e M AP FORW ARDACCESSSIGNALLING req. Ca nc el MAP Proc edures to MSC-B' from 3G_MSC-B UE/MS on 3G_MSC-B (UT RAN) Canc el MAP Proc edures from MSC-B' Call Releas e Can cel MAP Procedures W ait for a ccess by UE/MS ? Yes No to MSC-B' Cancel MAP Procedures IDLE Wa it for UE/MS on MSC-B' (UMTS to GSM Ho) Figure 43 (sheet 56 of 78): Handover control procedure in 3G_MSC-A 3GPP from Network or 3G_MSC-B
  • 190. Release 1999 190 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Procedure for Handove r in 3G_MSC-A Sheet57(78) Bas ic SRNS Relocation to 3G_MS C-B Crcuit Connec tion required 17 MAP-P REPAREHA NDOVER req. [Iu-RLC-REQ UE ST] to 3G_MS C-B Wait For Ack nowledgement from 3G_MSC-B (SRNS Relocation) Handover Number? MAP-P REPAREHA NDOVER res p. [MAP ERROR] from 3G_MSC-B MAP-PREPARE HANDOVER resp. [IU-RLC-FA ILURE] from 3G_MS C-B MAP-PREPAREHANDOVER resp. [IU-RLC-REQUEST -ACK] from 3G_MSC-B Not Requested Requested I_CONNECT (IAM) to 3G_MSC-B using Handover Number W ait for Connec tion from 3G_MSC-B (SRNS Relocation) 16 22 Figure 43 (sheet 57 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 191. Release 1999 191 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet58(78) Procedure for Handove r in 3G_MSC-A W ait For Ack nowledgement from 3G_MSC-B (SRNS Relocation) ERRO R Canc el MAP Re sources from 3G_MSC-B in 3G_MSC-A Call Re lease Iu-RELEASE-REQ UE ST from RNS-A to Network From UE or Network Call Release Release Resources in RNS-A Canc el MAP Resources to 3G_MS C-B IDLE 16 Figure 43 (sheet 58 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 192. Release 1999 192 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet59(78) Procedure for Handove r in 3G_MSC-A W ait for Connection from 3G_MSC-B (SRNS Relocation) Iu -RELE ASEREQ UEST from RNS-A I_COMPLETE (ACM) from 3G_MSC-B MAP-PAS req. [IU-IREL-REQ UEST ] from 3G_MS C-B Queue M es sages for UE in 3G_MSC-A (Allowed onc e in this state) Wait f or Connec tion from 3G_MSC-B (SRNS Relo cation) ERROR Call Releas e to UE and Network Releas e Res ources in RNS-A from 3G_MS C-B or Network I_DISCONNECT (REL) to 3G_MSC-B Set T703 W ait for Comp letion on 3G_MSC-B (SRNS Relocation) F rom UE or Netwo rk Call Release Iu-RELOCATION COMMAND to RNS-A Set Up the Handov er Device (A llowed once in this s tate ) to 3G_MSC-B in 3G_MSC-A Internal mess age in 3G_MSC-A Cancel MAP Procedures I_DISCONNECT (REL) to 3G_MS C-B 16 Figure 43 (sheet 59 of 78): Handover control procedure in 3G_MSC-A 3GPP IDLE
  • 193. Release 1999 193 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet60(78) Procedure for Handove r in 3G_MSC-A W ait for Comp letion on 3G_MSC-B (SRNS Relocation) MAP-S ENDEND-SIG NA L req. [I U-RLC-COMPLET E] from 3G_MSC-B Reset T703 (Allowed onc e in this state) MAP-PAS req. [I U-RLC-DET ECT ] from 3G_MSC-B I-ANSW ER (ANM) from 3G_MSC-B (Allowed once in this s tate) MA P-PAS re q. [IU-IRE L-REQ UE ST ] from 3G_MSC-B Iu-RELEASE-REQ UE ST from RNS-A Release Resourc es on RNS-A Yes Co nnect Handov er Device (option) W ait for UE on 3G_MSC-B? No Wait f or Completion on 3G_MS C-B (SRNS Relocation) Forward queu ed messages via 3G_MSC-B Us e M AP FORWA RD-ACCESSSIGNAL LING req Call Release to Ne twork and UE Release MAP Resourc es to 3G_MSC-B in 3G_MSC-A Re lease Re sources on RNS-A Connect Handove r Device (op tio n) I_DIS CO NNECT (REL) t o 3G_MSC-B Call on 3G_MSC-B (UT RAN) IDLE Wait f or Completion on 3G_MS C-B (SRNS Relocation) Figure 43 (sheet 60 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 194. Release 1999 194 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet61(78) Procedure for Handove r in 3G_MSC-A Wait f or Completion on 3G_MS C-B (SRNS Relocation) I_DISCONNECT (REL) from 3 G_ MSC-B IuRELO CATIONCANCE L from RNS-A Res et T703 Forward q ueued messages for UE via RNS-A Cancel MAP Procedures Call Releas e Internal to 3 G_ MSC-A Cancel MAP Procedures I_DISCONNECT (REL) to 3G_MSC-B Canc el MAP Proc edures from 3G_MSC-B Release Handover Devic e I_DISCONNECT (REL) to 3G_MSC-B Canc el MAP Proc edures In 3G _MSC-A and to 3G_MS C-B Release Handov er Device Internal to 3G_MSC-A Release Resources RNS-A I_DISCONNE CT (REL) to 3G_MSC-B Call in P rogres s on 3G_MS C-A (UT RAN) In ternal to 3G_MSC-A Wa it for Comp letion on 3G_MS C-B (SRNS Re location) Releas e Handove r Dev ice in 3G_MSC-A to 3G_MSC-B from Network Re lease Handov er Device In 3G_MSC-A and to 3G_MSC-B Release Handover Device Expiry T7 03 W ait for Completion on 3G_MSC-B (SRNS Reloc ation) IDLE Figure 43 (sheet 61 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 195. Release 1999 195 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet62(78) Procedure for Handove r in 3G_MSC-A Call on 3G_MS C-B (UT RAN) MAP-P AS req. [IU-IRELREQUEST] from 3 G_MS C-B MAP-PREPARESUB SEQUENTHANDOVER req. [IU-RLCREQUEST] from 3G_MSC-B 24 Known 3G_MSC? Call on 3G_MSC-B (UTRAN) No From UE or Network Call Releas e MAP-SEND-ENDS IG NAL resp. to 3G_MSC-B Yes Canc el MAP proc edures 3G_ MSC-B ' Call Release Whic h 3G_MSC? from 3G_MSC-B to Network and UE 3G_MSC-A 25 Known RNS? No Yes Res ourc es on new RNS? No I_DISCONNECT (RE L) to 3G_MS C-B Yes IuRELO CATIONREQ UEST to RNS-B MAP-PRE PA RESUBSEQUENTHANDOVER res p. [MAP E RROR] to 3G_MSC-B MAP-P REPARESUBSEQUENTHA NDOVER res p. [IU-RLC-FAILURE] to 3G_MS C-B No Set T701 Circuit Connection? Yes Wait for Channel Allocation (SRNS Relocation) UE o n 3G_MSC-B (UTRAN) Call on 3G_MSC-B (UTRAN) Figure 43 (sheet 62 of 78): Handover control procedure in 3G_MSC-A 3GPP IDLE
  • 196. Release 1999 196 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet63(78) Procedure for Handove r in 3G_MSC-A Wait for Channel Allocation (SRNS Relocation) IuRELOCATIONFA ILURE from RNS-B Iu-RELO CATIONREQUEST-ACK. from RNS-B (Allowed once in this state) MAP-PAS req. [IU-I REL-REQ UEST] from 3G_MSC-B Release Resources in RNS-B M AP -PREPARES UBS EQ UE NT HANDOVER resp [IU-RLC-REQUESTA CK] to 3G_MSC-B No Circuit Connect ion? Call Re lease MAP-S ENDENDSIGNAL resp to 3G_MS C-B Release Resourc es in RNS-B I_DISCONNE CT (REL) to 3G_MSC-B Call o n 3G_MSC-B (UTRAN) Yes Se t Up Handove r Dev ice Set T704 MAP-PREPARESUB SEQUENT HANDOVER resp. [IU-RLC-FAILURE] to 3 G_ MSC-B Call on 3G_MSC-B (UTRAN) Wait for Acc es s by UE (SRNS Relocation) IDLE Figure 43 (sheet 63 of 78): Handover control procedure in 3G_MSC-A 3GPP From UE or Network Ca nc el Channel RNS-B Reset T 701 Res et T701 Queue Mess ages for UE in 3G_MSC-A Expiry T7 01
  • 197. Release 1999 197 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet64(78) Procedure for Handove r in 3G_MSC-A Wait for access by UE (SRNS Relocation) Iu-RELOCATIO N DETE CT from RNS-B I u-RELO CATIONCOMPLETE f rom RNS-B No Res et T704 Expiry T704 Call Releas e Circ uit Connection? to Network Yes Releas e Res ources on RNS-B Conn ec t Handover Dev ic e (option) Connect Handover Device (option) Forward queued mes sages for UE via RNS-B Cancel MAP Procedures MAP-SEND-ENDS IG NAL resp. t o 3G_MSC-B No in 3G_MS C-A to 3G_MSC-B I_DISCO NNECT (REL) to 3G_MS C-B Circuit Connection? Yes Rele as e Handover Dev ice I _DISCONNECT (RE L) to 3G_MSC-B Call in Progress on MSC-A (UTRAN) W ait for ac cess by UE (SRNS Reloca tio n) IDLE Figure 43 (sheet 64 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 198. Release 1999 198 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet65(78) Procedure for Handove r in 3G_MSC-A W ait for acc es s by UE (SRNS Relocation) MAP-PAS req. [I U-RLCFAILURE] from 3G_MSC-B MAP-PAS req. [I U-IRELRE QUES T] from 3G_MSC-B Iu-RELEASEREQUEST from RNS-B Forward queu ed messages via 3G_MSC-B (Allowed once in this state) Canc el MAP Proc edures fro m Network Call Releas e (Allowed once in this state) Us e MAP -FORW ARDACCESS-SIGNALLING req. Re lease Re sources on RNS-B Circu it Connec tion? No Yes Re lease Handov er Device Call on 3G_MSC-B (UT RAN) UE on 3G_MS C-B (UT RAN) Wait for access by UE (SRNS Relocation) Figure 43 (sheet 65 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 199. Release 1999 199 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Procedure for Handove r in 3G_MSC-A Sheet66(78) Sub sequent SRNS Reloc ation from 3G_MSC-B to 3G _MSC-B' Circ uit Connection required 25 MAP-PREPARE-HANDOVER req [IU-RL C-REQ UEST ] to 3G _MSC-B' W ait for Ack from 3G_MSC-B' (SRNS Relocation) MAP-PRE PA REHANDOVER res p. [IU-RLC-FAILURE] from 3G_MSC-B ' MAP-P REPAREH ANDOVER res p.. [I U-RLC-REQUEST -ACK] from 3G_MSC-B' Handov er Number? Not Requested Requested MAP-PREPARESUBSEQUENT HA NDOVER resp. [IU-RLC-FAILURE] to 3 G_MS C-B I_CONNECT (IAM) to 3G_MS C-B' using Han dov er Number W ait for Connection from 3G_MSC-B' (SRNS Relocation) Call on 3G_MSC-B (UTRAN) 26 Figure 43 (sheet 66 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 200. Release 1999 200 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet67(78) Procedure for Handove r in 3G_MSC-A W ait for Ack from 3G_MSC-B' (SRNS Relocation) ERRO R Re lease MAP Re sources from 3G_MSC-B' from 3G_MSC-B or Network ERRO R Call Release Canc el MAP Proc edures to 3G _MSC-B' MAP-P AS req. [IU-IREL-REQUEST] from 3G_MS C-B Call on 3G_MSC-B (UT RAN) to 3G _MSC-B' MAP-S ENDEND-SIGNA L resp. to 3G_MS C-B Cancel MAP Procedures ERRO R From UE or Network to 3G_MSC-B' Release Handov er Devic e MAP-P REPARESUBSEQUENTHA NDOVER res p. to 3G_MS C-B I_DISCONNECT (REL) to 3G_MSC-B W ait for Ac k from 3G _MSC-B' (SRNS Reloc ation) IDLE Figure 43 (sheet 67 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 201. Release 1999 201 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet68(78) Procedure for Handove r in 3G_MSC-A W ait for Connection from 3G_MSC-B' (SRNS Relocation) I_COM PLE TE (ACM) from 3G_MSC-B' Set up Handov er Device MAP-P AS req. [IU-IRE LREQUEST] from 3G_ MSC-B ' from 3G_MSC-B' or Network fro m UE or Network ERRO R (Allowed once in this state) Call Releas e MAP-PA S req. [IU-IREL REQ UEST ] from 3G_MSC-B W ait f or Connection f rom 3G _MSC-B' (SRNS Relo cation) MAP-PREPARE-SUBSEQ UENT-HA NDOVER res p. [I U-RLC-REQUEST -ACK] to 3G_MS C-B Cancel MAP Procedures Queue m es sages for UE in 3G_MSC-A to 3G_MSC-B' to 3G _MSC-B' Canc el MAP Proc edures W ait for Comp letion on 3G _MSC-B' (SRNS Relocation) E RROR M AP -PREPARES UBS EQ UE NTHANDO VER resp. to 3G_MSC-B to 3G_MSC-B and 3G _MSC-B' MAP -SENDE ND-SIGNAL res p to 3G_MSC-B I_ DISCONNECT (RE L) to 3G_MSC-B' Call Release Set T703 Cancel MAP Procedures to Network and UE I_DISCO NNECT (REL) to 3G_MSC-B and 3G_MSC-B' Call o n 3G_MSC-B (UTRAN) IDLE Figure 43 (sheet 68 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 202. Release 1999 202 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet69(78) Procedure for Handove r in 3G_MSC-A W ait for Comp letion on 3G _MSC-B' (SRNS Relocation) Reset T703 I_ANSWER (ANM) from 3G_MSC-B ' MAP-P AS req. [IU-IRELREQUEST] from 3G_MS C-B MAP-P AS req. [IU-RLC-DETECT] from 3G _MSC-B' MAP-SEND-ENDSIGNAL req. [I U-RLC-COMPLET E] from 3G_MSC-B' MA P-PAS req. [IU-IRELREQUEST ] from 3G_MSC-B' (A llowed once in this s tate) Yes Connec t Handover Device (option) Co nnect Handov er Device (option) (Allowed onc e in this state) Wait for acces s by UE? No Forward queu ed messages f or UE via 3G _MSC-B' Releas e Handove r D ev ice Us e MAP -FORW ARDACCESS-SIGNALLING req. MAP-S ENDEND-SIG NA L resp. to 3G_MS C-B to 3G_MS C-B and 3G _MSC-B' to Network and UE I_DISCONNE CT (REL) to 3G_MSC-B Redefine 3G_MSC-B' as 3G_MSC-B Call on 3G_MSC-B (UT RAN) Cancel MAP Procedures Call Releas e I_DISCO NNECT (REL) to 3G_MSC-B and 3G _MSC-B' W ait for Completion from 3G _MSC-B' (SRNS Reloc ation) Figure 43 (sheet 69 of 78): Handover control procedure in 3G_MSC-A 3GPP IDLE
  • 203. Release 1999 203 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet70(78) Procedure for Handove r in 3G_MSC-A W ait for Comp letion on 3G _MSC-B' (SRNS Relocation) MA P-PAS re q. [IU-RLCFAILURE] from 3G_MSC-B Expiry T703 Res et T703 Ca nc el MAP Proc edures from 3G_MSC-B Canc el MAP Proc edures from 3G_MSC-B' Cancel MAP Procedures Call Releas e I_DISCONNECT (REL) to 3G_ MSC-B ' Release Handover Devic e I_ DISCONNECT (REL) to 3G_MS C-B to 3G _MSC-B' From Network or 3G_MSC-B Releas e Handover Device Release Handov er Device I_ DISCONNECT (REL) to 3G_MSC-B ' W ait for a ccess by UE? Yes No 3G_MSC-B Connec tion? Yes Cancel MAP Procedures to 3G_MSC-B' No Use MAPFORW ARDACCE SS SIGNALLING req. Call Re lease IDLE Forward queued mes sages for UE via 3G_MSC-B I_DISCONNECT (REL) to 3G _MSC-B' to Netwo rk Call on 3G_MSC-B (UTRAN) IDLE Figure 43 (sheet 70 of 78): Handover control procedure in 3G_MSC-A 3GPP Wait f or Co mpletion on 3G _MSC-B ' (SRNS Relocation)
  • 204. Release 1999 204 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet71(78) Procedure for Handove r in 3G_MSC-A Bas ic SRNS Relocation to 3G_MS C-B no Circuit Connection requ ired 22 Queue M es sages for UE in 3G_MSC-A Iu-Relocation Command to RNS-A Set T703 Wait for UE on 3G_MSC-B (SRNS Relocation) (Allowed once in this state) MAP-S ENDEND-SIG NA L req. [I U-RLC-COMPLET E] from 3G_MSC-B Reset T703 (Allowed once in this state) MAP-PA S req. [IU-IRE LREQ UE ST ] from 3G_MSC-B Yes Re lease Re sources on RNS-A MAP-PAS req. [I U-RLC-DET ECT ] from 3G_MSC-B Iu-RE LEA SE REQUEST from RNS-A Release Resourc es on RNS-A W ait for UE on 3G_MSC-B? No UE on 3G_MSC-B (UT RAN) Us e M AP FORWA RD-ACCESSSIGNALLING req. W ait for UE o n 3G_MSC-B (SRNS Relo cation) Call Release to Network and UE Release MAP Resourc es Forward queu ed messages f or UE via 3G_MSC-B to 3G_MSC-B in 3G_MSC-A IDLE Wait for UE on 3G_MSC-B (SRNS Relocation) Figure 43 (sheet 71 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 205. Release 1999 205 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet72(78) Procedure for Handove r in 3G_MSC-A Wait for UE on 3 G_MS C-B (SRNS Relocation) Cancel MAP Procedures Iu-RELO CATIONCANCEL from RNS-A In 3G _MSC-A and to 3 G_MS C-B Res et T703 Forward queued mes sages for UE via RNS-A in 3G_MSC-A to 3G_MSC-B from 3G_ MSC-B Expiry T7 03 Call Re lease Canc el MAP Proc edures Release Resourc es RNS-A Release Resources RNS-A Cancel MAP Procedures Call in P rogress on 3 G_MS C-A (UT RAN) W ait for UE o n 3G_MSC-B (SRNS Relo cation) IDLE Wait for UE on 3G_MSC-B (SRNS Relocation) Figure 43 (sheet 72 of 78): Handover control procedure in 3G_MSC-A 3GPP from Network
  • 206. Release 1999 206 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Procedure for Handove r in 3G_MSC-A Sheet73(78) UE Es tablished on 3G_MSC-B without a Circ uit Connec tion UE on 3G_MS C-B (UT RAN) Reque st for Circ uit Es tablishment From 3G_MS C-B M AP -PREPARES UBS EQ UE NTHANDO VER req. [IU-RLCREQUEST] from 3G_MSC-B Canc el MAP Proc edures Call Release From UE or Network Call Releas e to Network MAP-SEND-ENDS IG NAL resp. to 3G_MSC-B MAPPREPAREHANDOVER re q. [NULL] [IU-RASGR EQ UE ST ] to 3G_MSC-B Wait F or Response from 3G_MSC-B (SRNS Relocation) 24 IDLE Figure 43 (sheet 73 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 207. Release 1999 207 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Procedure for Handove r in 3G_MSC-A Sheet74(78) Circ uit Connection E stablis hme nt to 3G_MS C-B W ait For Response from 3G_MSC-B (SRNS Relocation) MAP-P REPAREH ANDOVER res p. [Handover Number] [IU-RA SG-COMPLETE] from 3G_MSC-B Call Release MAP-SENDEND-SIGNAL res p. to 3G_MSC-B I_CONNECT (IAM) to 3G _MSC-B using Han dov er Number W ait for Comp lete from 3G_MSC-B (SRNS Relocation) F rom UE or Network IDLE Figure 43 (sheet 74 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 208. Release 1999 208 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet75(78) Procedure for Handove r in 3G_MSC-A W ait For Response from 3G_MSC-B (SRNS Relocation) MAP-P REPAREH ANDOVER res p. [M AP ERROR] from 3G_MSC-B MAP -PREPAREHANDOVER resp. [IU-RASGFA ILURE] from 3G_MS C-B Cance l MAP Proce dures Call Re lease Failure Res po nse to Circ uit Establishment Request MAP-PA S req. [IU-IREL-REQUEST] from 3G_MSC-B (A llowed once in this s tate ) UE on 3G_MSC-B (UTRAN) UE on 3 G_MS C-B (UT RAN) Failure IDLE Figure 43 (sheet 75 of 78): Handover control procedure in 3G_MSC-A 3GPP from 3G_MSC-B to Netwo rk Res po nse to Circuit Establishment Request
  • 209. Release 1999 209 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet76(78) Procedure for Handove r in 3G_MSC-A W ait for Comp lete from 3G_MSC-B (SRNS Relocation) I_COM PLE TE (ACM) from 3G_MSC-B MAP-PAS req. [I U-IRELREQ UEST ] from 3G_MSC-B (Allowed once in this state) Call Re lease From UE or Network I-ANSW ER (ANM) from 3G_MSC-B from 3G_MSC-B Succes s W ait for Comp lete from 3G_MSC-B (SRNS Relocation) Respons e to Circuit E stablis hment Request Res po nse to Circuit Establishment Request Call on 3G_MSC-B (UTRAN) Canc el MAP Proc edures MAP-S ENDEND-SIGNAL res p. to 3G_MSC-B I_DISCONNECT (REL) to 3G_MSC-B Failure IDLE Figure 43 (sheet 76 of 78): Handover control procedure in 3G_MSC-A 3GPP
  • 210. Release 1999 210 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Procedure for Handove r in 3G_MSC-A Sheet77(78) Subsequent SRNS Relocation from 3G_MSC-B to 3G_MSC-B' no Circuit Connection requ ired. 26 MAP-P REPARESUBSEQUENTHA NDOVER res p. [I U-RLC-REQUEST -ACK] to 3G_MS C-B Queue M es sages for UE in 3G_MSC-A Set T703 W ait for UE on 3G _MSC-B' (SRNS Relocation) MAP-P AS req. [IU-RLC-DETECT] from 3G _MSC-B' MAP-S ENDEND-SIGNAL req [I U-RLC-COMPLET E] from 3G_MSC-B' Reset T703 Forward queu ed messages f or UE via 3G _MSC-B' MAP-P AS req. [IU-IRE LREQUEST] from 3G_ MSC-B ' Yes (Allowed once in this state) W ait for acces s by UE? No Us e M AP FORWA RD-ACCESSSIGNAL LING req to 3G_MSC-B and 3G_MSC-B' Redefine 3G_MSC-B' as 3G_MSC-B UE on 3G_MSC-B (UT RAN) (Allowed once in this st ate) to Network and UE W ait for UE on 3G_MSC-B' (SRNS Reloc ation) Canc el MAP Proc edures Call Re lease IDLE Figure 43 (sheet 77 of 78): Handover control procedure in 3G_MSC-A 3GPP MAP-PAS req. [I U-IRELREQ UEST ] from 3G_MSC-B
  • 211. Release 1999 211 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_A_H O Sheet78(78) Procedure for Handove r in 3G_MSC-A Wait for UE on 3G _MSC-B' (SRNS Relocation) MA P-PAS re q. [IU-RLCFAILURE] from 3G_MSC-B Expiry T703 Res et T703 Forward queu ed messages f or UE via 3G_MSC-B Ca nc el MAP Proc edures UE on 3G_MSC-B (UT RAN) from 3G_MSC-B Us e M AP FORW ARDACCESSSIGNALLING req. to 3G _MSC-B' Canc el MAP Proc edures from 3G_MSC-B' Call Releas e Can cel MAP Procedures W ait for a ccess by UE ? Yes No to 3G_MSC-B ' Cancel MAP Procedures IDLE Wait for UE on 3G _MSC-B' (SRNS Re location) Figure 43 (sheet 78 of 78): Handover control procedure in 3G_MSC-A 3GPP from Network or 3G_MSC-B
  • 212. Release 1999 212 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_H O Sheet1 (54) Procedures for Handov er in 3G_MSC-B IDLE MAP-PREP ARE -HANDOVER req. [IU-RLC-REQUEST] from 3G_ MSC-A MAP-P REPARE-HANDO VER req. [A-HO-REQ UEST] from 3G_MSC-A To UMTS Known RNS? 6 To GSM Type of handover? 5 No Yes Not Requested Han dov er Number? Requested MAP-PREPARE HANDOV ER resp [A-HO-FAILURE] to MSC-A MA P-A LLOCATE HANDOVER-NUMBER req. to VLR Set T601 Iu-RELOCATIONREQUE ST to RNS-B Wait f or Channel or Handover Number (G SM to UMTS Ho) IDLE Figure 44 (sheet 1 of 54): Handover control procedure in 3G_MSC-B 3GPP
  • 213. Release 1999 213 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_HO Sheet2(54) Procedures for Handover in 3G_ MSC-B Wait fo r Channel or Handover Number (GSM to UMTS Ho) Iu-RELOCATIONREQUEST-ACK from RNS-B MAP-ALLOCATEHANDOVERNUMBER resp. from VLR Wait fo r Ch annel Allocation Re set T6 01 No t Supported LOCATIONRE PORTING Iu-RELO CATIONREQUEST-ACK from RNS-B Supporte d Iu-LOCATIONREPORTINGCONTROL to RNS-B Ha ndo ver Nu mber? Re set T601 Re que sted LOCATIONRE PORTING No t Requested Supporte d Wait fo r Ha ndo ver Number Allocation MAP-PREPAREHA NDOVER resp. [A-HO-REQUE ST-ACK] to MSC-A No t Supp orted Iu-LOCA TIONREPORTINGCONTROL to RNS-B MAP-ALLOCATEHANDOVERNUMBER resp. from VLR MAP-PREPAREHANDOVER resp. [A-HO-REQUEST- ACK] [Hand over Number] to MSC-A Set T6 04 Set T6 10 Wait fo r UE/MS on RNS-B (GSM to UMTS Ho) Wait fo r Connection fro m MSC-A (GSM to UMTS Ho) Figure 44 (sheet 2 of 54): Handover control procedure in 3G_MSC-B 3GPP
  • 214. Release 1999 214 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_H O Sheet3 (54) Procedures for Handov er in 3G_MSC-B Wait for Channel or Handover Number (G SM to UMTS Ho) Wait for Channel Allocation (GSM to UMTS Ho) Iu-RELOCATIONFAILURE from RNS-B Re lease Re sources in RNS-B Wa it for Chann el or Handov er Number (GSM to UMTS Ho) Iu-Relas eREQUEST from RNS-B Ex piry T 601 W ait for Hand ov er Number Alloc ation (G SM to UMTS Ho) ERRO R Indication from VLR Release Resources in RNS-B MAP-P REPAREHA NDOVER res p. [M AP ERROR] to MS C-A Ca nc el Ch annel on RNS-B MAP-PRE PARE HANDOVER resp. [A-HO-FAILURE] to MSC-A IDLE I DLE Figure 44 (sheet 3 of 54): Handover control procedure in 3G_MSC-B 3GPP
  • 215. Release 1999 215 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_H O Procedures for Handov er in 3G_MSC-B Sheet4 (54) Basic GSM to UMTS handover from MSC-A to 3G_MSC-B Circ uit Connection required W ait for Connection from MSC-A (G SM to UMTS Ho) I_CONNECT (IAM) from MSC-A (Us es Handover No.) Reset T610 To MSC-A in 3G_MSC-B Iu-RELEA SE REQUEST from RNS-B Ex piry T 610 Cancel MAP Procedures Can cel MAP Procedures e.g. MAPABO RT from MSC-A MAP-PAS req. [A -CLEARRE QUES T] to MSC-A Cance l MAP Proce dures MAP -SEND-HANDOV ERREPORT res p. to VLR-B Set T604 I_COMPLETE (ACM) to MS C-A W ait for acces s by UE/MS on RNS-B (G SM to UMTS Ho) Release Radio Resourc es on RNS-B IDLE Figure 44 (sheet 4 of 54): Handover control procedure in 3G_MSC-B 3GPP To MSC-A in 3G_MSC-B
  • 216. Release 1999 216 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_H O Sheet5 (54) Procedures for Handov er in 3G_MSC-B W ait for acces s by UE/MS on RNS-B (G SM to UMTS Ho) Iu-RE LE ASEREQ UEST from RNS-B Iu-RELOCATIONCOMPLE TE from RNS-B Expiry T6 04 from MSC-A MAP-P AS req [A -CLEARREQ UEST] to MSC-A Res et T604 I_DISCONNE CT (REL) to MSC-A Reset T604 ANM Sent? Cancel MAP Procedure Yes I_DISCO NNECT (REL) from MSC-A Releas e Res ources on RNS-B No Iu-RELO CAT IONDETECT from RNS-B I_ANS WER (ANM) to MS C-A to MSC-A in 3G_MSC-B MAP-S ENDEND-SIG NA L req. [A-HO-CO MP LE TE] to MS C-A Call in Progres s on 3G_MSC-B (UT RAN) I_ANSW ER (ANM ) to MSC-A Cancel MAP Procedures Release Resources on RNS-B MAP-P AS req [A-HO-DE TECT] to MS C-A W ait for ac cess by UE /MS on RNS-B (G SM to UMTS Ho) IDLE Figure 44 (sheet 5 of 54): Handover control procedure in 3G_MSC-B 3GPP Wait for Disconnect (GS M to UMT S Ho)
  • 217. Release 1999 217 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_HO Sheet6(54) Procedures for Handover in 3G_ MSC-B Ca ll in Progress on 3G_MSC-B (GSM) Forward Messages to UE/MS MAP-SENDEND-SIGNAL resp. from 3G_MSC-A A-CLEARREQUEST from BSS-A A-HO-PERFORMED from BSS MAP-PAS req. [A-HO-PERFORMED] to 3G_ MSC-A MAP-PAS req . [A-CLEAR-RE QUEST] to 3G_MSC-A Ca ll in Pr ogress on 3G_ MSC-B (GSM) Cance l MAP Procedures Release Resou rces in BSS-A 3G_MSC-A disconnected? Cance l MAP Procedures I_DISCONNECT (REL) from 3G_MSC- A Yes Release Resou rces in BSS-A from 3G_MSC-A A-HANDOVERREQUIRED fro m BSS-A No Wait for Disconnect (UMTS to GSM Ho) I_DISCONNECT (REL) to 3G_MSC-A I_DISCONNECT (REL) from 3G_MSC- A IDLE Ca ll in Pr ogress on 3G_MSC-B (GSM) IDLE Figure 44 (sheet 6 of 54): Handover control procedure in 3G_MSC-B 3GPP 2
  • 218. Release 1999 218 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_H O Sheet7 (54) Procedures for Handov er in 3G_MSC-B 2 Yes Known 3G_MSC? No No Handover allowed to Cell? Yes Wh ich 3G _MSC? 3G_MSC-A/3G_ MSC-B ' 3G_MSC-B MAP-PRE PA RESUBSEQUENTHANDOVER req. [A-HO-REQ UE ST] to 3G_MSC-A Known RNS? No Yes 1 Resources on RNS-B? No Yes No Send Reje ct? Yes A-HANDOVERREJECT to B SS-A Circuit Con nec tion? Set T 611 No Yes Call in P rogres s on 3G_MS C-B (G SM ) UE/MS on 3 G_ MSC-B (GSM) 3 W ait for Response (G SM to UMTS Ho) Figure 44 (sheet 7 of 54): Handover control procedure in 3G_MSC-B 3GPP
  • 219. Release 1999 219 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_HO Procedures for Handover in 3G_ MSC-B Sheet8(54) Handover fr om BSS-A to RNS-B on 3G_MSC-B 3 Iu-RELOCATION-REQUEST to RNS-B Set T6 01 Wait for Channel (GSM to UMTS Ho) IuRELOCATIONREQUESTACK from RNS-B Re set T6 01 LOCATIONREPORTING IuRELOCATIONFAILURE from RNS-B Expiry T601 Re set T6 01 A-CLEAR- REQUEST from BSS-A Supporte d No t Supported Iu-LOCATIONREPORTINGCONTROL to RNS-B Queue Messages in 3G_MSC-B MAP-PAS req [A-CLEA RREQUEST] to 3G_ MSC-A Handover Command to UE/MS via BSS-A Set Up Handover Device MAP- SEND-ENDSIG NAL resp. from 3G_ MSC-A Release Resou rces on RNS-B Cance l MA P Procedures To 3 G_MSC-A in 3G_MSC-B Release Resou rces on BSS-A Set T6 02 Wait for access by UE/MS (GSM to UMTS Ho) Cance l Channel request on RNS-B 1 Figure 44 (sheet 8 of 54): Handover control procedure in 3G_MSC-B 3GPP Wait fo r Disconnect (GSM to UMTS Ho)
  • 220. Release 1999 220 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_H O Sheet9 (54) Procedures for Handov er in 3G_MSC-B W ait for acces s by UE/MS (G SM to UMTS Ho) Iu-RELO CATIONDETECT fo rm RNS-B Iu-RELOCATIONCOMPLE TE from RNS-B A-HANDOVER F AILURE from BS S-A Reset T602 MAP-PAS req. [A-HO-PERF ORMED] to 3G_MS C-A Circu it Connec tion? No Circuit Connection? Yes No Yes Connect Handover Device (Op tio nal) Co nnect Handov er De vice (Optional) Res et T602 Forward queu ed messages via RNS-B Forward queued messages via BS S-A Release Resources in BSS-A Releas e Res ources in RNS-B Circu it Connec tion? No No Yes Yes Releas e Han dov er Dev ice Re lease Handov er Device Call in Progres s on 3G_MSC-B (UT RAN) Circuit Con nec tion? UE /MS on 3G_MS C-B (UT RAN) UE/MS on 3G_MSC-B (G SM) W ait for access b y UE/MS (GSM to UMT S Ho) Call in P rogres s on 3G_MS C-B (G SM ) Figure 44 (sheet 9 of 54): Handover control procedure in 3G_MSC-B 3GPP
  • 221. Release 1999 221 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_H O Sheet10(54) Procedures for Handov er in 3G_MSC-B W ait for acces s by UE/MS (G SM to UMTS Ho) Expiry T602 Release Resources in BSS-A Release Reso urces in RNS-B Release Resources in RNS -B and B SS-A MAP-SEND-ENDSIGNAL resp. from 3G_MSC-A A -CLEARREQ UEST from B SS-A Iu-RELEASEREQUEST from RNS-B Yes Re lease Handov er Device W ait for ac cess by UE /MS? No MAP-PAS req. [A-CLEAR-REQUEST] to 3G_MS C-A Canc el MAP Proc edures T o 3G_MS C-A in 3G_ MSC-B To 3G_MSC-A in 3G_MSC-B Canc el MAP Proc edures Re lease Handov er Device Release Resourc es in RNS-B I_DISCONNE CT (REL) to 3G_MSC-A IDLE Release Resources in RNS-B and B SS-A MA P-PAS re q. [A-CLEAR-REQUEST] to 3G_MSC-A Wait for access by UE/MS (GSM to UMTS Ho) W ait for Disc onnec t (GSM to UMTS Ho) Figure 44 (sheet 10 of 54): Handover control procedure in 3G_MSC-B 3GPP
  • 222. Release 1999 222 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_H O Procedures for Handov er in 3G_MSC-B Sheet11(54) Subsequent GS M to UMTS Handov er from 3G_MSC-B to 3G_MS C-A Wait for Re spons e (GS M to UMT S Ho) M AP -PREPARES UBS EQ UE NTHANDO VER resp. [A-HO -FA ILURE or MAP E RROR] from 3G_MSC-A MAP-PREPARE SUBSEQ UENTHANDOVER resp. [A-HO -REQUESTACK] from 3 G_ MSC-A Res et T611 A-CLEARREQUEST fro m BSS-A MAP-PA S req. [A-CLEARREQ UE ST] to 3G_MSC-A Reset T 611 Release Resources in RNS-B Expiry T6 11 MAP-SEND-ENDSIGNAL resp. from 3G_MSC-A in 3G_MSC-B to 3G_MSC-A Cancel MAP Procedures Handov er Command to UE /MS via B SS-A Releas e Res ources in BSS-A Set T604 Wait for Ack. from 3G_MSC-A (GS M to UMT S Ho) Wait for Disconnect (GS M to UMT S Ho) 1 Figure 44 (sheet 11 of 54): Handover control procedure in 3G_MSC-B 3GPP
  • 223. Release 1999 223 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_H O Sheet12(54) Procedures for Handov er in 3G_MSC-B Wait for Ack. from 3G_MSC-A (GS M to UM TS Ho) MAP-SENDENDSIGNAL res p. fro m 3G_MSC-A Ex piry T 604 A-HANDOVERFAILURE from BSS-A A -CLEARREQ UEST from B SS-A Release Reso urces in BSS-A Circuit Conn ec tion? to 3G_MSC-A in 3 G_ MSC-B Release Resourc es in BSS-A to 3G_MSC-A Releas e Res ources in BSS-A MAP-PAS req. [A-CLE ARREQUEST] to 3G_MSC-A Cancel MAP Procedures Res et T604 Canc el MAP Proc edures No MAP-PAS req. [A-HO-FAILURE] to 3G_MS C-A Circu it Connec tion? Yes Wait for Disconnect (GS M to UM TS Ho) Re set T604 No Yes Call in Progres s on 3G_MSC-B (G SM ) IDLE Figure 44 (sheet 12 of 54): Handover control procedure in 3G_MSC-B 3GPP UE /MS on 3G_MS C-B (GSM)
  • 224. Release 1999 224 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_H O Procedures for Handov er in 3G_MSC-B Sheet13(54) Bas ic G SM to UMTS handover from MSC-A to 3G_MSC-B no Circuit Connectio n requ ired Wait for UE /MS on RNS-B (GS M to UMT S Ho) Iu-RELEASEREQ UEST from RNS-B Iu-RELO CATIONCOMPLETE from RNS-B Res et T604 Expiry T6 04 from MSC-A MAP -PAS req [A-CLE ARREQUEST] to MSC-A Iu RELO CATI ONDETECT from RNS-B MAP-SENDEND-SIGNAL req. [A-HO COMPLETE] to MSC-A Canc el MAP Proc edures to MS C-A in 3G_MSC-B MAP-PAS req. [A-HO-DETECT] to MSC-A UE/MS on 3 G_MS C-B (UT RAN) Cancel MAP Procedure W ait for UE/MS o n RNS-B (GSM to UMT S Ho) Releas e Res ources on RNS-B IDLE Figure 44 (sheet 13 of 54): Handover control procedure in 3G_MSC-B 3GPP
  • 225. Release 1999 225 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_H O Sheet14(54) Procedures for Handov er in 3G_MSC-B Forward Mess ages to UE/MS UE/MS on 3 G_MS C-B (GSM) MA P-S ENDEND-SIG NA L resp. from MSC-A A-HANDOVERREQ UIRED fro m BSS-A MAP-PREPAREHANDOVER req. [NULL] [A-ASG-REQ UE ST] from 3G_MSC-A Releas e Res ources in BSS-B MAP-ALLOCAT EHANDOV ER-NUMBER req. to VLR A-ASSIGNMENTREQUEST to B SS-A IDLE 2 Wa it f or Assignment or Handover Number (UMTS to GSM Ho) Figure 44 (sheet 14 of 54): Handover control procedure in 3G_MSC-B 3GPP
  • 226. Release 1999 226 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_H O Procedures for Handov er in 3G_MSC-B Sheet15(54) Circ uit Connection Es tablis hment on 3G_MS C-B Wait for Assignment or Handover Numb er (GS M to UMT S Ho) MAP -ALLOCATEHANDOVERNUMBE R resp. from VL R Iu-RAB-AS SIGNMENTRESPO NSE from RNS-B Wait for Handover Number Alloc ation W ait for As signment Iu-RA B-ASSIGNMENTRESPO NSE from RNS-B MAP -ALLOCATEHANDOVERNUMBE R resp. from VL R MAP -PREPAREHANDOVER resp. [Handover Number] [A-ASG-CO MPLET E] to MSC-A Set T610 Wait for Connect from MSC-A (GS M to UMT S Ho) Figure 44 (sheet 15 of 54): Handover control procedure in 3G_MSC-B 3GPP
  • 227. Release 1999 227 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_H O Sheet16(54) Procedures for Handov er in 3G_MSC-B W ait for Handover Number Allocation (GSM to UMT S Ho) Wait for Assignme nt (GS M to UM TS Ho) Iu -RABASSIGNME NT RE SP ONSE with unsucces sful res ult from RNS-B MAP-P REPAREHA NDOVER res p. [A-AS G-FA ILURE] to MS C-A E RROR Wait for Handover Number Allocation (GS M to UMT S Ho) W ait for Ass ignment or Handover Number (G SM to UMTS Ho) W ait for Assign ment o r Handov er Number (GSM to UMT S Ho) W ait for Ass ignment or Handover Number (G SM to UMTS Ho) Wa it for Ass ignment (G SM to UMTS Ho) MA P-S ENDEND-SIG NA L resp. from MSC-A Indic ation from VLR Iu-RELEASEREQUEST fro m RNS-B M AP -PREPAREHANDO VER resp. [MAP ERROR] to MSC-A MAP-PA S req. [A-CLEAR-REQUEST ] to MS C-A to MSC-A and VLR-B Canc el MAP Proc edures to VLR-B Cancel MAP Procedures Releas e Res ources in RNS-B UE/MS on 3G_MSC-B (UT RAN) IDLE Figure 44 (sheet 16 of 54): Handover control procedure in 3G_MSC-B 3GPP
  • 228. Release 1999 228 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_H O Sheet17(54) Procedures for Handov er in 3G_MSC-B W ait for Conn ec t from MSC-A (G SM to UMTS Ho) I_CONNECT (IAM) from MSC-A (Us es Handover No.) Reset T610 to MSC-A in 3G_MSC-B Call on 3G_MSC-B (UT RAN) MAP-P AS req. [A-CLEA R_REQUEST] to MSC-A Cancel MAP Procedures Cancel MAP Procedures MAP -SEND-HANDOV ERREPORT res p. to VLR-B I_ COMPLETE (ACM) to MSC-A Iu-RELEASE-REQ UE ST from RNS-A Ex piry T 610 to MSC-A in 3G_MSC-B Release Radio Resourc es on RNS-B IDLE Figure 44 (sheet 17 of 54): Handover control procedure in 3G_MSC-B 3GPP
  • 229. Release 1999 229 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_H O Sheet18(54) Procedures for Handov er in 3G_MSC-B Wait for Co nnect from MSC-A (GS M to UMT S Ho) MAP-SENDEND-SIGNAL res p. from MS C-A I_DISCONNECT (REL) from MSC-A from MSC-A Release Resources on RNS-B UE/MS on 3 G_MS C-B (UT RAN) IDLE Cance l MAP Procedure Re lease Re sourc es on RNS-B IDLE Figure 44 (sheet 18 of 54): Handover control procedure in 3G_MSC-B 3GPP
  • 230. Release 1999 230 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_H O Sheet19(54) Procedures for Handov er in 3G_MSC-B 5 No Known BSS? Yes Not Requested Han dov er Number? Requested MAP-PREPARE HANDOV ER resp [A-HO-FAILURE] to 3G_MSC-A MA P-A LLOCATE HANDOVER-NUMBER req. to VLR Set T401 A-HANDOVERREQUE ST to BS S-B Wait f or Channel or Handover Number (UMTS to GSM Ho) IDLE Figure 44 (sheet 19 of 54): Handover control procedure in 3G_MSC-B 3GPP
  • 231. Release 1999 231 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_H O Sheet20(54) Procedures for Handov er in 3G_MSC-B Wait for Channel or Handover Numb er (UMTS to GSM Ho) MAP-A LLOCAT EHANDOVERNUMBER res p. from VLR A-HANDOV ERREQ UEST -ACK from B SS-B Res et T401 Handover Number? Requested Not Requested W ait for Channel Allocation W ait for Handover Number A lloc ation M AP -PREPAREHANDO VER resp. [ A-HO-REQUEST -ACK] t o 3G_MSC-A A-HANDOVERREQUEST-ACK from BSS-B MAP-ALLOCATEHANDOVERNUMBE R resp. from VLR Reset T401 MAP-PREPARE HANDO VE R resp. [A-HO-REQUEST-ACK] [Handov er Number] to 3G_MSC-A Set T404 S et T410 Wait for UE /MS on B SS-B (UMTS to GSM Ho) W ait for Connection from 3G_MSC-A (UMTS to GSM Ho) Figure 44 (sheet 20 of 54): Handover control procedure in 3G_MSC-B 3GPP
  • 232. Release 1999 232 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_H O Sheet21(54) Procedures for Handov er in 3G_MSC-B Wait for Channel or Handover Number (UMTS to GSM Ho) Wait for Channel Alloc ation (UMTS to GSM Ho) A-HANDOVERFAILURE from BSS-B Wa it for Chann el or Handov er Number (UMT S to GS M Ho) A_CLEARREQUEST from BS S-B Ex piry T 401 W ait for Hand ov er Number Alloc ation (UMTS to GSM Ho) ERRO R Indication from VLR Release Resources in B SS-B Re lease Re sources in BSS-B MAP-P REPAREHA NDOVER res p. [M AP ERROR] to 3G_MS C-A Ca nc el Ch annel on BSS-B MAP-PRE PA REHANDOVER re sp. [A-HO-FAILURE] to 3G_MSC-A IDLE I DLE Figure 44 (sheet 21 of 54): Handover control procedure in 3G_MSC-B 3GPP
  • 233. Release 1999 233 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_H O Procedures for Handov er in 3G_MSC-B Sheet22(54) Bas ic UMTS to GSM han dov er from 3G_MSC-A to 3G_MSC-B Circ uit Connection required W ait for Connection from 3G_MSC-A (UMTS to GSM Ho) I_CONNECT (IAM) from 3G_MSC-A (Us es Handover No.) Reset T410 To 3G_MSC-A in 3G_MSC-B Ex piry T 410 Cancel MAP Procedures A-CLE AR-REQUE ST from B SS-B Can cel MAP Procedures MAP-PAS req. [A -CLEARRE QUES T] to 3G_MS C-A e.g. MAP-ABO RT from 3 G_ MSC-A Cance l MAP Proce dures MAP -SEND-HANDOV ERREPORT res p. to VLR-B Set T404 I_COMPLETE (ACM) to 3G_MS C-A W ait for acces s by UE/MS on BSS-B (UMTS to GSM Ho) Release Radio Resourc es on BS S-B IDLE Figure 44 (sheet 22 of 54): Handover control procedure in 3G_MSC-B 3GPP To 3G_MSC-A in 3G_MSC-B
  • 234. Release 1999 234 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_H O Sheet23(54) Procedures for Handov er in 3G_MSC-B W ait for acces s by UE/MS on BSS-B (UMTS to GSM Ho) A -CLEARREQ UEST from BS S-B A-HANDOVERCOMPLE TE from BSS-B Expiry T4 04 fro m 3G_MSC-A MAP-P AS req [A -CLEARREQ UEST] to MSC-A Res et T404 I_DISCO NNECT (REL) to 3G_MSC-A Reset T404 ANM Sent? Cancel MAP Procedure Yes I_DISCO NNECT (REL) from 3G_MSC-A Releas e Res ources on BSS-B No A-HANDOVERDET ECT from BSS-B I_ANS WER (ANM) to 3G_MS C-A to 3G_MS C-A in 3G_MSC-B MAP-S ENDEND-SIG NA L req. [A-HO-CO MP LE TE] to 3G_MS C-A Call in Progres s on 3G_MSC-B (G SM ) I_ANSW ER (ANM ) to 3G_MSC-A Cancel MAP Procedures Release Resources on B SS-B MAP-P AS req [A-HO-DE TECT] to 3G_MS C-A W ait for ac ce ss by UE/MS on BSS-B (UMTS to GSM Ho) IDLE Figure 44 (sheet 23 of 54): Handover control procedure in 3G_MSC-B 3GPP Wait for Disconnect (UMTS to GSM Ho)
  • 235. Release 1999 235 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_HO Sheet24(54) Procedures for Handover in 3G_ MSC-B Ca ll in Progress on 3G_MSC-B (UTRAN) Forward Messages to UE/MS MAP-SENDEND-SIGNAL re sp. fro m 3G_ MSC-A Iu-RELE ASEREQUEST from RNS-A Iu-LOCA TIONREPORT from RNS MAP-PAS req. [A-CLEARREQUEST] to 3G_MSC-A MAP-PAS req. [A-HOPERFORMED] to 3G_ MSC-A Ca ll in Pr ogress on 3G_ MSC-B (UTRAN) Cance l MAP Procedures Release Resou rces in RNS-A 3G_MSC-A disconnected? Cance l MAP Procedures I_DISCONNECT (REL) from 3G_MSC- A Yes Release Resou rces in RNS-A from 3G_MSC-A Iu- RELOCATIONRE QUIRED fro m RNS-A No Wait for Disconnect (GSM to UMTS Ho) I_DISCONNECT (REL) to 3G_MSC-A I_DISCONNECT (REL) from 3G_MSC- A IDLE Ca ll in Pr ogress on 3G_MSC-B (UTRAN) IDLE Figure 44 (sheet 24 of 54): Handover control procedure in 3G_MSC-B 3GPP 8
  • 236. Release 1999 236 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_H O Sheet25(54) Procedures for Handov er in 3G_MSC-B 8 Yes Known MSC? No Handover allowed to Cell? No Yes Wh ich 3G _MSC? MS C-A/MSC-B' MS C-B MAP-PRE PA RESUBSEQUENTHANDOVER req. [A-HO-REQ UE ST] to MS C-A Known BSS? No Yes 7 Resources on BSS-B? No Yes No Send Reje ct? Yes Iu-RELOCATIONPREPARATIONFAILURE to RNS-A Circuit Con nec tion? Set T 411 No Yes Call in P rogres s on 3G_MS C-B (UTRAN) UE/MS on 3 G_ MSC-B (UTRAN) 9 W ait for Response (UMT S t o GSM Ho) Figure 44 (sheet 25 of 54): Handover control procedure in 3G_MSC-B 3GPP
  • 237. Release 1999 237 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_H O Procedures for Handov er in 3G_MSC-B Sheet26(54) UMTS to GS M Handov er from RNS-A to BSS-B on MSC-B 9 A-HANDOV ER-REQUEST to BS S-B Set T401 Wait for Channel (UMTS to GSM Ho) A-HANDOVERRE QUES TACK from BSS-B A-HANDOVERF AILURE from BS S-B Ex piry T 401 Iu-RELEASE-REQ UEST from RNS-A Reset T 401 Reset T401 MAP-SEND-ENDS IG NAL resp. from 3G_MSC-A Queue Messages in MSC-B MAP-PAS req [A-CLEARREQ UE ST ] to 3G_MSC-A Han dov er Command to UE/MS via Iu-RELOCATION-COMMAND to RNS-A Release Resourc es on BS S-B Canc el MAP Proc edures Canc el Channel request on B SS-B T o 3G_MSC-A in MSC-B Releas e Res ources on RNS-A Set Up Handov er Device Set T402 W ait for acces s by UE/MS (UMTS to GSM Ho) Wait for Disconnect (UMTS to GSM Ho) 7 Figure 44 (sheet 26 of 54): Handover control procedure in 3G_MSC-B 3GPP
  • 238. Release 1999 238 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_H O Sheet27(54) Procedures for Handov er in 3G_MSC-B W ait for acces s by UE/MS (UMTS to GSM Ho) A -HANDOV ERDETECT form B SS-B A-HANDOVERCOMPLE TE from BSS-B Iu-RELOCATION CANCEL from RNS-A Reset T402 MAP-PAS req. [A-HO-PERF ORMED] to 3G_MS C-A Circu it Connec tion? No Circuit Connection? Yes No Yes Connect Handover Device (Op tio nal) Co nnect Handov er De vice (Optional) Res et T402 Forward queu ed messages via BS S-B Forward queued messages via RNS-A Re lease Re sources in RNS-A Releas e Res ources in BSS-B Circu it Connec tion? No No Yes Yes Releas e Han dov er Dev ice Re lease Handov er Device Call in Progres s on 3G_MSC-B (G SM ) Circuit Con nec tion? UE /MS on 3G_MS C-B (GSM) UE/MS on 3G_MSC-B (UT RAN) W ait for access b y UE/MS (UMTS to GSM Ho) Call in P rogres s on 3G_MS C-B (UT RAN) Figure 44 (sheet 27 of 54): Handover control procedure in 3G_MSC-B 3GPP
  • 239. Release 1999 239 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_H O Sheet28(54) Procedures for Handov er in 3G_MSC-B W ait for acces s by UE/MS (UMTS to GSM Ho) Expiry T402 Release Resources in RNS-A Release Reso urces in BSS-B Release Resources in BSS -B and RNS-A MAP-SEND-ENDSIGNAL resp. from 3G_MSC-A Iu -RELE ASEREQ UEST from RNS-A A-CLEARREQUEST from BSS-B No Re lease Handov er Device W ait for acc ess by UE/MS? Yes MAP-PAS req. [A -CLEARREQ UEST ] to 3G_MS C-A Canc el MAP Proc edures To 3G_MSC-A in 3G_MSC-B T o 3G_MS C-A in 3 G_ MSC-B Canc el MAP Proc edures Re lease Handov er Device Release Resourc es in BS S-B I_DISCONNE CT (REL) to 3G_MSC-A IDLE Release Resources in BSS -B and RNS-A MAP-PAS req. [A-CLE ARREQUEST] to 3G_MSC-A W ait for Dis connect (UMTS to GSM Ho) Wait for ac cess by UE/MS (UMTS to GSM Ho) W ait for Disc onnec t (UMTS to GSM Ho) Figure 44 (sheet 28 of 54): Handover control procedure in 3G_MSC-B 3GPP
  • 240. Release 1999 240 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_H O Procedures for Handov er in 3G_MSC-B Sheet29(54) Sub sequent UMTS to GSM Handover from 3G_MSC-B to MS C-A Wait for Re spons e (UMTS to GSM Ho) M AP -PREPARES UBS EQ UE NTHANDO VER resp. [A-HO -FA ILURE or MAP E RROR] from MS C-A MAP-PREPARE SUBSEQ UENTHANDOVER resp. [A-HO -REQUESTACK] from MSC-A Res et T411 Iu-RELEASEREQUEST fro m RNS-A MAP-PAS req. [A-CLEARREQ UE ST] to MS C-A Reset T 411 Release Resources in B SS-B Expiry T4 11 MAP-SEND-ENDSIGNAL resp. from MSC-A in 3G_MSC-B to MS C-A Cancel MAP Procedures Releas e Res ources in RNS-A Relocation Command to RNS-A Set T404 Wait for Ack. from MSC-A (UMTS to GSM Ho) Wait for Disconnect (UMTS to GSM Ho) 7 Figure 44 (sheet 29 of 54): Handover control procedure in 3G_MSC-B 3GPP
  • 241. Release 1999 241 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_H O Sheet30(54) Procedures for Handov er in 3G_MSC-B Wait for Ack. from MSC-A (UMTS to GSM Ho) MAP-SENDENDSIGNAL res p. from MSC-A Ex piry T 404 Iu-RELOCATIONCANCEL from RNS-A Iu -RELE ASEREQ UEST from RNS-A Release Reso urces in RNS-A Circuit Conn ec tion? to MSC-A in 3 G_ MSC-B Release Resourc es in RNS-A to MSC-A Releas e Res ources in RNS-A MAP-PAS req. [A-CLE ARREQUEST] to MSC-A Cancel MAP Procedures Res et T404 Canc el MAP Proc edures No MAP-PAS req. [A-HO-FAILURE] to MS C-A Circu it Connec tion? Yes Wait for Disconnect (UMTS to GSM Ho) Re set T404 No Yes Call in Progres s on 3G_MSC-B (UTRAN) IDLE Figure 44 (sheet 30 of 54): Handover control procedure in 3G_MSC-B 3GPP UE /MS on 3G_MS C-B (UT RAN)
  • 242. Release 1999 242 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_H O Procedures for Handov er in 3G_MSC-B Sheet31(54) Basic UMTS to G SM handover from 3G _MSC-A to 3G_MSC-B no Circuit Connectio n requ ired Wait for UE /MS on B SS-B (UMTS to GSM Ho) A-CLEARREQ UE ST from B SS-B A -HANDOV ERCOMPLETE from B SS-B Res et T404 Expiry T4 04 fro m 3G_MSC-A MAP-PAS req [A-CLEARREQUEST] to 3G_MSC-A A -HANDOV ERDETECT from B SS-B MA P-SENDEND-SIG NAL req. [A-HO-CO MP LETE] to 3 G_MS C-A Canc el MAP Proc edures to 3G_MSC-A in 3G_MSC-B MAP-PAS req. [A-HO-DETECT] to 3G_MSC-A UE/MS on 3 G_MS C-B (GSM) Cancel MAP Procedure W ait for UE/MS o n BS S-B (UMTS to GSM Ho) Releas e Res ourc es on BSS-B IDLE Figure 44 (sheet 31 of 54): Handover control procedure in 3G_MSC-B 3GPP
  • 243. Release 1999 243 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_HO Sheet32(54) Procedures for Handover in 3G_ MSC-B Fo rward Messag es to UE/MS UE /MS on 3G_MSC-B (UTRAN) MAP-SENDE ND-SIGNAL r esp. from 3G_MSC-A IuRELOCATIONREQUIRED from RNS-A MAP-PREPAREHANDOVER req . [NULL] [A-ASG-REQUEST] from MSC-A Release Resou rces in RNS-B MAP-ALLOCA TEHANDOVER- NUMBER req. to VLR Iu- RAB-ASSIGNEMENTREQUEST to RNS-A IDLE Wait fo r Assignment or Handover Number (GSM to UMTS Ho) 8 Iu-LOCA TIONREPORT from RNS MAP-PAS req. [A-HOPERFORMED] to 3G_ MSC-A UE /MS on 3G_ MSC-B (UTRAN) Figure 44 (sheet 32 of 54): Handover control procedure in 3G_MSC-B 3GPP
  • 244. Release 1999 244 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_H O Procedures for Handov er in 3G_MSC-B Sheet33(54) Circ uit Connection Es tablis hment on 3G_MS C-B Wait for Assignme nt or Handover Numb er (UMTS to GSM Ho) MAP -ALLOCATEHANDOVERNUMBER resp. from VLR A-AS SIGNMENTCOMPL ETE from BSS-B Wait for Handover Number Allocation W ait for As signment A-ASSIGNMENT COMPLETE from B SS-A MAP -ALLOCATEHANDOVERNUMBER resp. from VLR MAP-PREPAREHANDOVER resp. [Handover Number] [A-ASG-CO MP LET E] to 3G_MSC-A Set T410 Wait for Co nnect from 3G_MSC-A (UMTS to GSM Ho) Figure 44 (sheet 33 of 54): Handover control procedure in 3G_MSC-B 3GPP
  • 245. Release 1999 245 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_H O Sheet34(54) Procedures for Handov er in 3G_MSC-B W ait for Handover Number Allocation (UMT S to GS M Ho) Wait for Assignme nt (UMTS to GSM Ho) A-ASSIGNMENTFAILURE from BSS-A MAP-P REPAREHA NDOVER res p. [A-AS G-FA ILURE] to 3G_MS C-A E RROR Wait for Handover Number Allocation (UMTS to GSM Ho) W ait for Ass ignment or Handover Number (UMT S t o GSM Ho) W ait for Assign ment o r Handov er Number (UMTS to GSM Ho) W ait for Ass ignment or Handover Number (UMTS to GSM Ho) Wa it for Ass ignment (UMTS to GSM Ho) MA P-S ENDEND-SIG NA L resp. from 3G_MSC-A Indic ation from VLR M AP -PREPAREHANDO VER resp. [MAP ERROR] to 3G_MSC-A A-CLEAR-REQUEST fro m BSS-B MAP-PA S req. [A-CLEAR-REQUEST ] to 3G_MSC-A to 3G_MSC-A and VLR-B Canc el MAP Proc edures to VLR-B Cancel MAP Procedures Releas e Res ources in BSS-B UE/MS on 3G_MSC-B (G SM ) IDLE Figure 44 (sheet 34 of 54): Handover control procedure in 3G_MSC-B 3GPP
  • 246. Release 1999 246 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_H O Sheet35(54) Procedures for Handov er in 3G_MSC-B W ait for Conn ec t from 3G_MSC-A (UMTS to GSM Ho) I_CONNECT (IAM) from 3G_MSC-A (Us es Handover No.) Reset T410 to 3G_MS C-A in 3G_MSC-B Call on 3G_MSC-B (G SM ) MAP-P AS req. [A-CLEA R_REQUEST] to 3G_MSC-A Cancel MAP Procedures Cancel MAP Procedures MAP -SEND-HANDOV ERREPORT res p. to VLR-B I_ COMPLETE (ACM) to 3G_MSC-A A-CLEAR-REQ UEST from BSS-A Ex piry T 410 to 3G_MSC-A in 3G_MSC-B Release Radio Resourc es on BS S-B IDLE Figure 44 (sheet 35 of 54): Handover control procedure in 3G_MSC-B 3GPP
  • 247. Release 1999 247 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_H O Sheet36(54) Procedures for Handov er in 3G_MSC-B Wait for Connect from 3G_MSC-A (UMTS to GSM Ho) MAP-SENDEND-SIGNAL res p. from 3G_MS C-A I_DISCONNECT (REL) from 3 G_MS C-A from 3G_MS C-A Release Resources on BS S-B UE/MS on 3 G_ MSC-B (GSM) IDLE Cancel MAP Procedure Releas e Res ourc es on BSS-B IDLE Figure 44 (sheet 36 of 54): Handover control procedure in 3G_MSC-B 3GPP
  • 248. Release 1999 248 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_H O Sheet37(54) Procedures for Handov er in 3G_MSC-B 6 No Known RNS? Yes Not Requested Han dov er Number? Requested MAP-PREPARE HANDOV ER resp [IU-RLC-FA ILURE] To 3G_MSC-A MA P-A LLOCATE HANDOVER-NUMBER req. to VLR Set T801 Iu-RELOCATIONREQUE ST to RNS-B Wait f or Channel or Handover Number (SRNS Re location) IDLE Figure 44 (sheet 37 of 54): Handover control procedure in 3G_MSC-B 3GPP
  • 249. Release 1999 249 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_H O Sheet38(54) Procedures for Handov er in 3G_MSC-B Wait for Channel or Handover Numbe r (SRNS Relocation) MAP-A LLOCAT EHANDOVERNUMBER res p. from VLR Iu-REL OCAT IONREQ UEST-ACK from RNS-B Res et T801 Handover Number? Requested Not Requested Wait for Channel Allocation (SRNS Relocation) W ait for Handover Number A lloc ation MAP-PREPAREHA NDOVER resp. [IU-RLC-REQUEST -ACK] to 3 G_MSC-A Iu-RELOCATIONREQUEST-ACK from RNS-B MAP-ALLOCATEHANDOVERNUMBE R resp. from VLR Reset T801 MAP-PREPARE HANDO VE R resp. [IU-RLC-REQUEST-ACK] [Handov er Number] to 3G_MSC-A Set T804 S et T 810 Wait for UE on RNS-B (SRNS Relocation) W ait for Connection from 3G_MS C-A (SRNS Reloc ation) Figure 44 (sheet 38 of 54): Handover control procedure in 3G_MSC-B 3GPP
  • 250. Release 1999 250 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_H O Sheet39(54) Procedures for Handov er in 3G_MSC-B Wait for Channel or Handover Number (SRNS Re location) Iu-RELOCATIONFAILURE from RNS-B Wait for Channel Alloc ation (SRNS Relo cation) Wa it for Chann el or Handov er Number (SRNS Reloc ation) Iu-RE LEA SE REQUEST from RNS-B Ex piry T 801 W ait for Hand ov er Number Alloc ation (SRNS Relocation) ERRO R Indication from VLR Release Resources in RNS-B Re lease Re sources in RNS-B MAP-P REPAREHA NDOVER res p. [M AP ERROR] to 3G_MS C-A Ca nc el Ch annel on RNS-B MAP-PRE PA REHANDOVER re sp. [IU-RLC-FAI LURE] to 3G_MSC-A IDLE I DLE Figure 44 (sheet 39 of 54): Handover control procedure in 3G_MSC-B 3GPP
  • 251. Release 1999 251 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_H O Procedures for Handov er in 3G_MSC-B Sheet40(54) Bas ic S RNS Relocation from 3G_MSC-A to 3G_MSC-B Circ uit Connection required W ait for Connection from 3G_MSC-A (SRNS Relocation) I_CONNECT (IAM) from 3G_MSC-A (Us es Handover No.) Reset T810 To 3G_MSC-A in 3G_MSC-B Iu-RELEA SE REQUEST from RNS-B Ex piry T 810 Cancel MAP Procedures Can cel MAP Procedures e.g. MAP-ABORT from 3G_MSC-A MAP-PAS req. [IU-IRELRE QUES T] to 3G_MS C-A Cance l MAP Proce dures MAP -SEND-HANDOV ERREPORT res p. to VLR-B Set T804 I_COMPLETE (ACM) to 3G_MS C-A W ait for acces s by UE on RNS-B (SRNS Relocation) Release Radio Resources on RNS-B IDLE Figure 44 (sheet 40 of 54): Handover control procedure in 3G_MSC-B 3GPP To 3G_MSC-A in 3G_MSC-B
  • 252. Release 1999 252 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_H O Sheet41(54) Procedures for Handov er in 3G_MSC-B W ait for acces s by UE on RNS-B (SRNS Relocation) Iu-RE LE ASEREQ UEST from RNS-B Iu-RELOCATIONCOMPLE TE from RNS-B Expiry T8 04 fro m 3G_MSC-A MAP-P AS req [IU_IRELREQ UEST] to 3G_MS C-A Res et T804 I_DISCO NNECT (REL) to 3G_MSC-A Reset T804 ANM Sent? Cancel MAP Procedure Yes I_DISCO NNECT (REL) from 3G_MSC-A Releas e Res ources on RNS-B No Iu-RELO CAT IONDET ECT from RNS-B I_ANS WER (ANM) to 3G_MS C-A to 3G_MS C-A in 3G_MSC-B MAP-S ENDEND-SIG NA L req. [IU_ RLC-COMPLETE] to 3G_MS C-A Call in Progres s on 3G_MSC-B (UT RAN) Cancel MAP Procedures I _ANSW ER (ANM ) t o 3G_MSC-A Release Resources on RNS-B MAP-PAS req [IU-RLC-DE TECT] to 3G_MSC-A W ait for acces s by UE on RNS-B (SRNS Relocation) IDLE Figure 44 (sheet 41 of 54): Handover control procedure in 3G_MSC-B 3GPP Wait for Disconnect (SRNS Relocation)
  • 253. Release 1999 253 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_H O Sheet42(54) Procedures for Handov er in 3G_MSC-B Call in Progres s on 3G_MSC-B (UT RAN) Forward Mess ages to UE MAP-S ENDEND-SIG NA L resp. from 3G_MSC-A Iu-RELEASE-REQUEST from RNS-A MAP-PAS req. [IU-IREL-REQUEST] to 3G_MSC-A Cancel MAP Procedures Releas Resources in RNS-A 3G_MSC-A dis connected? Canc el MAP Proc edures I_DISCONNECT (REL) from 3G_MSC-A Yes Release Resourc es in RNS-A from 3G_MSC-A Iu-RELO CATIONREQUIRED from RNS-A No I_DIS CONNECT (REL) to 3G_MSC-A W ait for Disc onnec t I_ DISCONNECT (REL) from 3 G_ MSC-A IDLE Call in Progress on 3G_MSC-B (UTRAN) IDLE Figure 44 (sheet 42 of 54): Handover control procedure in 3G_MSC-B 3GPP 12
  • 254. Release 1999 254 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_H O Sheet43(54) Procedures for Handov er in 3G_MSC-B 12 Known 3G_MSC? Yes No Wh ich 3G _MSC? 3G_MS C-A/3G_MSC-B' MS C-B MAP-P REPA RESUBSEQUENTHANDOVER req. [IU-RLC-REQ UE ST ] to 3G_MSC-A Known RNS? No Yes 11 Resources on RNS-B? No Yes No Send Rejec t? Yes Iu-RELOCATIONPREPARA TION-F AIL URE to RNS-A Circuit Con nec tion? Set T8 11 No Yes Call in P rogres s on 3G_MS C-B (UTRAN) UE on 3G_MSC-B (UTRAN) 13 W ait for Response (SRNS Relocation) Figure 44 (sheet 43 of 54): Handover control procedure in 3G_MSC-B 3GPP
  • 255. Release 1999 255 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_HO Procedures for Handover in 3G_ MSC-B Sheet44(54) SRNS Rel ocation from RNS-A to RNS-B o n 3G_MSC-B 13 Iu-RELOCATION-REQUEST to RNS-B Set T8 01 Wait for Channel (SRNS Relocation) IuRELOCATIONREQUEST-ACK from RNS-B Iu-RELO CATIONFAILURE from RNS-B Expiry T801 Re set T8 01 MAP-SENDEND-SIGNAL resp. fro m 3G_ MSC-A Iu-RELE ASE-REQUEST from RNS-A Re set T8 01 Queue Messages in 3G_MSC-B No t supported Loca tion Reporting MAP-PAS req [IU-IRELREQUEST] to 3G_ MSC-A Supported Iu-LOCATION REPORTING CONTROL to RNS-B Release Resou rces on RNS-B Cance l MA P Procedures Cance l Ch annel request on RNS-B To 3 G_MSC-A in 3G_MSC-B Relocation Command to RNS-A Release Resou rces on RNS-A Set Up Handover Device Set T8 02 Wait for access by UE (SRNS Relocation) 11 Figure 44 (sheet 44 of 54): Handover control procedure in 3G_MSC-B 3GPP Wait fo r Disconnect (SRNS Relocation)
  • 256. Release 1999 256 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_HO Sheet45(54) Procedures for Handover in 3G_ MSC-B Wait for access by UE (SRNS Relocation) IuRELOCATIONCOMPLETE from RNS-B IuRELOCATIONDETECT form RNS-B IuRELOCATION CANCEL from RNS-A Re set T8 02 Ha ve security alg or ithms been changed? Yes No Protocol on E-interface RA NAP BSSMAP MAP-PAS req. MAP-PAS req. [A-HO[Iu -L OC-REPORT] PERFORMED] to 3G_ MSC-A to 3G_MSC-A Ci rcuit Co nne cti on? Circuit Conne cti on? No No Yes Yes Connect Handover Device (Optional) Re set T802 Connect Handover Device (O ptional) Forward queued me ssage s via RNS-A Fo rward queued messages via RNS-B Release Resou rces in RNS-B Release Resources in RNS-A No Ci rcuit Co nnecti on? Yes Ci rcuit Co nne cti on? No Release Handover Device Yes Release Handover Device UE on 3G_ MSC-B (UTRAN) Wait fo r access by UE (SRNS Relocation) Ca ll in Progress on 3G_MSC-B (UTRAN) Ca ll in Pr ogress on 3G_ MSC-B (UTRAN) UE on 3G_MSC-B (UTRAN) Figure 44 (sheet 45 of 54): Handover control procedure in 3G_MSC-B 3GPP
  • 257. Release 1999 257 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_H O Sheet46(54) Procedures for Handov er in 3G_MSC-B W ait for acces s by UE (SRNS Relocation) Expiry T802 Release Resources in RNS-A Release Reso urces in RNS-B Release Resources in RNS -B and RNS-A MAP-SEND-ENDSIGNAL resp. from 3G_MSC-A Iu -RELE ASEREQ UEST from RNS-A Iu-RELEASEREQUEST from RNS-B Yes Re lease Handov er Device W ait for acc ess by UE? No MAP-PAS req. [IU-IREL-REQUEST] to 3G_MS C-A Canc el MAP Proc edures T o 3G_MS C-A in 3G_ MSC-B To 3G_MSC-A in 3G_MSC-B Canc el MAP Proc edures Re lease Handov er Device Release Resourc es in RNS-B I_DISCONNE CT (REL) to 3G_MSC-A IDLE Release Resources in RNS -B and RNS-A MAP-PA S req. [IU-IREL-REQUEST] to 3G_MSC-A Wait for access by UE (SRNS Relo cation) W ait for Disc onnec t (SRNS Reloca tio n) Figure 44 (sheet 46 of 54): Handover control procedure in 3G_MSC-B 3GPP
  • 258. Release 1999 258 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_H O Procedures for Handov er in 3G_MSC-B Sheet47(54) Subsequent SRNS Relocation from 3G_MSC-B to 3G_MSC-A Wait for Re spons e (SRNS Relocation) MAP-PREPARE S UBS EQ UENTHANDO VE R resp. [IU-RLCREQUESTA CK] from 3G_MS C-A M AP -PREPARES UBS EQ UE NTHANDO VER resp. [IU-RLC-FAILURE or MAP E RROR] from 3G_MSC-A Res et T811 Iu-RELEASEREQUEST fro m RNS-A MAP-PAS req. [IU-IREL REQ UE ST] to 3G_MSC-A Reset T 811 Release Resources in RNS-B Expiry T8 11 MAP-SEND-ENDSIGNAL resp. from 3G_MSC-A in 3G_MSC-B to 3G_MSC-A Cancel MAP Procedures Releas e Res ources in RNS-A Relocation Command to RNS-A Set T804 Wait for Ack. from 3G_MSC-A (SRNS Relocation) Wait for Disconnect (SRNS Relocation) 11 Figure 44 (sheet 47 of 54): Handover control procedure in 3G_MSC-B 3GPP
  • 259. Release 1999 259 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_H O Sheet48(54) Procedures for Handov er in 3G_MSC-B Wait for Ack. from 3G_MSC-A (SRNS Relocation) MAP-SENDENDSIGNAL res p. fro m 3G_MSC-A Ex piry T 804 IuRELOCAT IONCANCEL from RNS-A Iu -RELE ASEREQ UEST from RNS-A Release Reso urces in RNS-A Circuit Conn ec tion? to 3G_MSC-A in 3 G_ MSC-B Release Resourc es in RNS-A to 3G_MSC-A Releas e Res ources in RNS-A MAP-PAS req. [IU-IRELREQUEST] to 3G_MSC-A Cancel MAP Procedures Res et T804 Canc el MAP Proc edures No MAP-PAS req. [I U-RLCFAILURE] to 3G_MS C-A Circu it Connec tion? Yes Wait for Disconnect (SRNS Relocation) Re set T804 No Yes Call in Progres s on 3G_MSC-B (UTRAN) IDLE Figure 44 (sheet 48 of 54): Handover control procedure in 3G_MSC-B 3GPP UE on 3G_MS C-B (UT RAN)
  • 260. Release 1999 260 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_H O Procedures for Handov er in 3G_MSC-B Sheet49(54) Bas ic S RNS Relocation from 3G_MSC-A to 3G_MSC-B no Circuit Connectio n requ ired Wait for UE on RNS-B (SRNS Relocation) Iu-RELEASEREQ UEST from RNS-B Iu-RELO CATIONCOMPLETE from RNS-B Res et T804 Expiry T8 04 fro m 3G_MSC-A MAP -PAS req [IU-IRELREQUEST] to 3G_MSC-A IuRELO CATIONDET ECT from RNS-B MAP-SENDEND-SIGNAL req. [IU-RLCCOMPLETE] to 3G_MSC-A Canc el MAP Proc edures to 3G_MSC-A in 3G_MSC-B MAP-PAS req. [IU-RLC-DETECT] to 3G_MSC-A UE on 3 G_MS C-B (UT RAN) Cancel MAP Procedure W ait for UE o n RNS-B (SRNS Reloc ation) Releas e Res ources on RNS-B IDLE Figure 44 (sheet 49 of 54): Handover control procedure in 3G_MSC-B 3GPP
  • 261. Release 1999 261 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_H O Sheet50(54) Procedures for Handov er in 3G_MSC-B Forward Mess ages to UE UE on 3 G_MS C-B (UT RAN) Iu-RELOCATIONREQ UIRED from RNS-A MA P-S ENDEND-SIG NA L resp. from 3G_MSC-A MAP-PREPARE HANDO VE R req. [NULL] [IU-RASG-REQUEST] from 3 G_MS C-A MAP-ALL OCAT EHANDOV ER-NUMBER req. to VLR Releas e Resources in RNS-B Iu-RAB-A SSIG NE MENTREQUEST to RNS-A IDLE 12 Wait fo r Assignment or Handover Number (SRNS Relocation) Figure 44 (sheet 50 of 54): Handover control procedure in 3G_MSC-B 3GPP
  • 262. Release 1999 262 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_H O Procedures for Handov er in 3G_MSC-B Sheet51(54) Circ uit Connection Es tablis hment on 3G_MS C-B Wait for Assignment or Handover Numb er (SRNS Relocation) MAP-ALLOCATEHANDOVERNUMBE R resp. from VLR Iu-RAB-AS SIGNMENTRESPO NSE from RNS-A Wait for Handover Number Allocation W ait for As signment (SRNS Reloc ation) Iu-RA B-ASSIGNMENTRESPONSE from RNS-A MAP -ALLOCATEHANDOVERNUMBE R resp. from VL R MAP -PREPAREHANDOVER resp. [Handover Number] [IU-RASG -COMPLETE] to 3G_MSC-A Set T810 Wait for Connect from 3G_MSC-A (SRNS Relocation) Figure 44 (sheet 51 of 54): Handover control procedure in 3G_MSC-B 3GPP
  • 263. Release 1999 263 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_H O Sheet52(54) Procedures for Handov er in 3G_MSC-B W ait for Handover Number Allocation (SRNS Reloc ation) Wait for Assignme nt (SRNS Relocation) Iu -RABASSIGNME NT RE SP ONSE with Uns uccess ful res ult from RNS-B MAP-P REPAREHA NDOVER res p. [IU-RA SGRESPONSE] to 3G_MS C-A E RROR Wait for Handover Number Allocation (SRNS Relocation) W ait for Ass ignment or Handover Number (SRNS Relocation ) W ait for Assign ment o r Handov er Number (SRNS Relo cation) W ait for Ass ignment or Handover Number (SRNS Relocation) Wa it for Ass ignment (SRNS Re location) MA P-S ENDEND-SIG NA L resp. from 3G_MSC-A Indic ation from VLR Iu-RELEASEREQUEST fro m RNS-A M AP -PREPAREHANDO VER resp. [MAP ERROR] to 3G_MSC-A MAP-PA S req. [IU-IREL-REQUEST] to 3G_MSC-A to 3G_MSC-A and VLR-B Canc el MAP Proc edures to VLR-B Cancel MAP Procedures Releas e Res ources in RNS-A UE on 3G_MSC-B (UT RAN) IDLE Figure 44 (sheet 52 of 54): Handover control procedure in 3G_MSC-B 3GPP
  • 264. Release 1999 264 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_H O Sheet53(54) Procedures for Handov er in 3G_MSC-B W ait for Conn ec t from 3G_MSC-A (SRNS Relocation) I_CONNECT (IAM) from 3G_MSC-A (Us es Handover No.) Reset T810 to 3G_MS C-A in 3G_MSC-B Call on 3G_MSC-B (UT RAN) MAP-P AS req. [IU-IREL-REQUEST] to 3G_MSC-A Cancel MAP Procedures Cancel MAP Procedures MAP -SEND-HANDOV ERREPORT res p. to VLR-B I_ COMPLETE (ACM) to 3G_MSC-A Iu-RELEASE-REQ UE ST from RNS-A Ex piry T 810 to 3G_MSC-A in 3G_MSC-B Release Radio Resourc es on RNS-A IDLE Figure 44 (sheet 53 of 54): Handover control procedure in 3G_MSC-B 3GPP
  • 265. Release 1999 265 3GPP TS 23.009 V3.14.0 (2003-06) Procedure 3G_MSC_B_H O Sheet54(54) Procedures for Handov er in 3G_MSC-B Wait for Connect from 3G_MSC-A (SRNS Relocation) MAP-SENDEND-SIGNAL res p. from 3G_MS C-A I_DISCONNECT (REL) from 3 G_MS C-A from 3G_MS C-A Release Resources on RNS-A UE on 3 G_ MSC-B (UTRAN) IDLE Cancel MAP Procedure Releas e Res ourc es on RNS-A IDLE Figure 44 (sheet 54 of 54): Handover control procedure in 3G_MSC-B 3GPP
  • 266. Release 1999 266 3GPP TS 23.009 V3.14.0 (2003-06) Annex A (informative): Change history Change history TSG CN# Spec Version Apr 1999 GSM 03.09 6.0.0 CR Rel N_Ver CN#03 CN#06 23.009 23.009 3.0.0 3.0.0 CR001r2 R99 3.1.0 CN#7 23.009 3.1.0 CR003 R99 3.2.0 CN#7 CN#7 CN#7 23.009 23.009 23.009 3.1.0 3.1.0 3.1.0 CR004 CR005 CR006 R99 3.2.0 R99 3.2.0 R99 3.2.0 CN#7 23.009 3.1.0 CR007 R99 3.2.0 CN#7 23.009 3.1.0 CR008r2 R99 3.2.0 15/05/00 23.009 3.2.0 - R99 3.2.1 TSG# NP-Tdoc WG Tdoc Spec CR NP-000278 N1-000638 23.009 002 4 NP-08 NP-000270 N1-000607 23.009 NP-08 NP-000270 N1-000608 NP-09 NP-000444 NP-10 SDLs SDLs Introduction of RANAP for intraUMTS inter-MSC relocation Clarifications of 3G_MSC-A and 3G_MSC-B roles Transcoder handling in the CN at inter-system handover and relocation Missing SDLs re-inserted by SDLs MCC for Figures 41 - 42 (GSM Handover control procedure in MSC-A and MSC-B) R99 C Old at vers B 3.2.1 New ver 3.3.0 009 R99 C 3.2.1 3.3.0 23.009 010 R99 C 3.2.1 3.3.0 N1-000922 23.009 012 R99 F 3.3.0 3.4.0 NP-000671 N1-001174 23.009 013 R99 F 3.4.0 3.5.0 NP-10 NP-000671 N1-001175 23.009 014 R99 F 3.4.0 3.5.0 NP-10 NP-000724 N1-001412 23.009 015 2 R99 F 3.4.0 3.5.0 NP-10 NP-000671 N1-001347 23.009 016 1 R99 F 3.4.0 3.5.0 NP-10 NP-000671 N1-001408 23.009 017 3 R99 F 3.4.0 3.5.0 NP-10 NP-10 NP-000673 NP-000671 N1-001304 N1-001372 23.009 23.009 019 020 1 R99 R99 F F 3.4.0 3.4.0 3.5.0 3.5.0 NP-10 NP-000671 N1-001403 23.009 021 1 R99 F 3.4.0 3.5.0 NP-11 NP-010123 N1-010086 23.009 018 2 R99 F 3.5.0 3.6.0 NP-11 NP-010207 N1-010321 23.009 024 R99 F 3.5.0 3.6.0 NP-11 NP-010207 N1-010427 23.009 026 R99 F 3.5.0 3.6.0 NP-12 NP-010270 N1-010913 23.009 034 R99 F 3.6.0 3.7.0 1 3 Comment Transferred to 3GPP CN1 Approved at CN#03 Introduction of UMTS functionalities in 23.009 Functional requirements for the use of RANAP over the E i/f Rev Rel NP-08 Subject 3GPP Title WI CR to 23.009 on Handover scenario for Multicall Clean-up of 3G_MSC-A_HO SDLs Clean-up of 3G_MSC-B_HO SDLs Correction to transcoder handling for R99 GSM to UMTS Handover: Directed Retry GSM to UMTS Handover: MAP parameter Target Cell ID GSM to UMTS Handover: Location Reporting in 3G MSC B Subsequent Handover procedure corrections Missing Subsequent Handover scenarios Reference clean-up ndication of Intra-MSC Intersystem handover from 3G_MSC-B to MSCA/3G_MSC-A UMTS to GSM handover: Directed Retry GSM to UMTS Handover: Location Reporting in 3G_MSC-B GSM to UMTS handover: addition of MAP parameter Target RNC ID Directed Retry procedure allignment Indication of Intra MSC handover from 3G_MSC-B to MSC-A/3G_MSC-A Multicall GSM/UMTS Interworking GSM/UMTS Interworking TrFo/OoBTC GSM/UMTS Interworking GSM/UMTS Interworking GSM/UMTS Interworking GSM/UMTS Interworking GSM/UMTS Interworking TEI GSM/UMTS Interworking GSM/UMTS Interworking GSM/UMTS Interworking GSM/UMTS Interworking GSM/UMTS Interworking Handover
  • 267. Release 1999 267 TSG# NP-Tdoc WG Tdoc Spec CR NP-13 NP-010494 N1-011111 23.009 NP-13 NP-010495 N1-011228 NP-13 NP-010494 NP-14 NP-14 Rev Rel 3GPP TS 23.009 V3.14.0 (2003-06) 040 C Old at vers Rel-4 F 3.7.0 New ver 3.8.0 23.009 046 R99 F 3.7.0 3.8.0 N1-011310 23.009 048 1 R99 F 3.7.0 3.8.0 NP-010651 NP-010682 N1-011556 N1-011971 23.009 23.009 054 056 2 R99 R99 F F 3.8.0 3.8.0 3.9.0 3.9.0 NP-14 NP-010682 N1-011806 23.009 059 R99 F 3.8.0 3.9.0 NP-14 NP-010691 N1-012026 revised 23.009 062 R99 F 3.8.0 3.9.0 NP-16 NP-020218 N1-021280 23.009 069 R99 F 3.9.0 3.10.0 NP-16 NP-020218 N1-021393 23.009 075 R99 F 3.9.0 3.10.0 NP-17 NP-020366 N1-021683 23.009 078 R99 F 3.10.0 3.11.0 2 1 R99 3.11.0 3.12.0 NP-18 NP-18 NP-020549 NP-020630 N1-022270 N1-022234 23.009 23.009 081 088 2 R99 R99 F F 3.11.0 3.12.0 3.11.0 3.12.0 NP-19 NP-030041 N1-030292 23.009 091 1 R99 F 3.12.0 3.13.0 NP-20 NP-030268 N1-030906 23.009 094 2 R99 F 3.13.0 3.14.0 3GPP Title WI GSM to UMTS Handover: Location Reporting in 3G_MSC-B for no call up case Correction of SDL figures in CRs 034 and 035 (N1010913, N1-010914) Usage of Location Reporting for Relocation and Intersystem Handover Multicall bearer selection Usage of Location Reporting for Relocation and Intersystem Handover E-interface protocol during the supervision phase GSM to UMTS Handover: Iu-LOCATION-REPORTING message reception Clarification of the end of supervision after inter-MSC handover Handling of Service Handover parameter in nonanchor Correction to codec handling in Inter-MSC Handover ETSI/MCC updated reference [2] to void and [2a] to TR instead of TS. MSC_A_HO SDL correction Clarification of the protocol to be used on the Einterface Further clarification of the protocol to the be used on the E-interface Correct text related to timer expiry for receipt of AHANDOVER-COMPLETE / Iu-RELOCATIONCOMPLETE GSM/UMTS Interworking Handover GSM/UMTS Interworking Multicall GSM/UMTS Interworking GSM/UMTS Interworking GSM/UMTS Interworking GSM/UMTS Interworking GSM/UMTS Interworking TrFOOoBTC TEI GSM/UMTS Interworking GSM/UMTS Interworking GSM/UMTS Interworking

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