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gsm,umts.ppt
- 1. BY – NAVJOTKAUR LECTURE-10 GPRS Architecture & 3 G CELLULAR SYSTEMS
- 2. What is GPRS? General Packet Radio Service (GPRS) is a new bearer service for GSM that greatly improves and simplifies wireless access to packet data networks GPRS applies packet radio principal to transfer user data packets in an efficient way b/w MS & external packet data network.
- 3. Benefits of GPRS New Data Services High Speed (Data Rate 14.4 – 115 kbps) Efficient use of radio bandwidth (Statistical Multiplexing) Circuit switching & Packet Switching can be used in parallel Constant connectivity
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- 5. Statistical Multiplexing … Statistical multiplexing is facilitated through packet mode or packet oriented communication, which amongst others is utilized in packet switched computer networks. Each stream is divided into packets that normally are delivered asynchronously in a first-come first-serve fashion. Alternatively, the packets may be delivered according to some scheduling discipline for fair queuing or differentiated and/or guaranteed quality of service. Statistical multiplexing of an analog channel, for example a wireless channel, is also facilitated through the following schemes:
- 6. Statistical Multiplexing … Random frequency-hopping orthogonal frequency division multiple access (RFH-OFDMA) Code-division multiple access (CDMA), where different amount of spreading codes or spreading factors can be assigned to different users. Statistical multiplexing normally implies "on-demand" service rather than one that pre-allocates resources for each data stream. Statistical multiplexing schemes do not control user data transmissions.
- 7. Salient Features ofGPRS Important step on the path to 3G Standardized by ETSI (European Telecommunications Standards Institute) GPRS is an overlay network over the GSM Provides Data Packet delivery service Support for leading internet communication protocols Billing based on volume of data transferred Utilizes existing GSM authentication and privacy procedures.
- 8. GPRS Terminals ClassA MS supports simultaneous operation of GPRS and GSM services Class B MS able to register with the n/w for both GPRS & GSM services simultaneously. It can only use one of the two services at a given time. Class C - MS can attach for either GPRS or GSM services
- 9. GPRS Network Elements GPRSArchitecture is same as GSM except few hardware modifications : GPRS includes GSNs SGSN : Serving GPRS Support Node GGSN : Gateway GPRS Support Node GPRS Register
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- 11. Interfaces Gb –Connects BSC with SGSN Gn – SGSN – SGSN/GGSN (in the same network) Gp – SGSN –GGSN (in different networks) Gf – For equipment querying at registering time Gi – Connects PLMN with external Packet Data Networks (PDNs) Gr – To exchange User profile between HLR & SGSN Gs – To exchange Database between SGSN & MSC Gd – Interface between SMS & GPRS
- 12. SGSN – ServingGPRS Support Node • Delivers data packets to mobile stations & vice- versa • Detect and Register new GPRS MS in its serving area • Packet Routing, Transfer & Mobility Management • Authentication, Maintaining user profiles • Its location register stores location info. & user profiles
- 13. GGSN – GatewayGPRS Support Node • Interfaces GPRS backbone network & external packet data networks • Converts the GPRS packets from SGSN to the PDP format • Converts PDP addresses change to GSM addresses of the destination user • Stores the current SGSN address and profile of the user in its location register • Performs authentication • Many-to- many relations among SGSNs & GGSNs
- 14. GPRS Register GPRSRegister is integrated with GSM-HLR. Maintains the GPRS subscriber data and Routing information. Stores current SGSN address
- 15. GPRS Backbone Network GSNs are connected through IP based backbone Two Backbones: Intra PLMN backbone networks that connects GSNs of the same PLMN & are private IP networks Inter PLMN backbone networks that connects GSNs of the different PLMN. Roaming agreement is necessary GPRS Tunneling protocol (GTP) PLMN- Inter PLMN interconnect are called Border gateways (performs security functions to protect Intra- PLMN backbone against unauthorized users and attacks).
- 16. Attachment & Detachment Procedure GPRS attach - User is registered in SGSN, after authentication check from HLR - SGSN assigns P-TMSI to MS •GPRS detach - Disconnection of MS from GPRS network is called GPRS detach - It can be initiated by MS or by network(SGSN or HLR)
- 17. Third Generation Vision Common spectrum worldwide – 1920-1980 MHz and 2110-2170 MHz Wide range of new services – Data centric (e..g.. Internet) and multimedia oriented – Data bit rates up to 2 Mb/s Seamless global roaming Improved security and performance Support a variety of terminal (from PDA to desktop) Intensive use of Intelligent Network (IN) technology
- 18. Why 3G? Higherbandwidth enables a range of new applications!! For the consumer Video streaming, TV broadcast Video calls, video clips – news, music, sports Enhanced gaming, chat, location services… For business High speed teleworking / VPN access Sales force automation Video conferencing Real-time financial information
- 19. Upgrade paths for2G Technologies IS-95 IS-136 & PDC GSM- EDGE GPRS HSCSD IS-95B Cdma2000-1xRTT Cdma2000-1xEV,DV,DO Cdma2000-3xRTT W-CDMA EDGE TD-SCDMA 2G 3G 2.5G 3GPP 3GPP2
- 20. UMTS UMTS isthe European vision of 3G. UMTS is an upgrade from GSM via GPRS or EDGE. The standardization work for UMTS is carried out by Third Generation Partnership Project (3GPP). Data rates of UMTS are: 144 kbps for rural 384 kbps for urban outdoor 2048 kbps for indoor and low range outdoor Virtual Home Environment (VHE)
- 21. UMTS Network Architecture SD MobileStation MSC/ VLR Base Station Subsystem GMSC Network Subsystem AUC EIR HLR Other Networks Note: Interfaces have been omitted for clarity purposes. GGSN SGSN BTS BSC Node B RNC RNS UTRAN SIM ME USIM ME + PSTN PLMN Internet
- 22. UMTS Network Architecture UMTS network architecture consists of three domains: Core Network (CN) : To provide switching, routing and transit for user traffic. UMTS Terrestrial Radio Access Network (UTRAN) : Provides the air interface access method for User Equipment. User Equipment (UE) : Terminals work as air interface counterpart for Node B. The various identities are: IMSI, TMSI, P-TMSI, TLLI, MSISDN, IMEI, IMEISV.
- 23. UMTS Frequency Spectrum •UMTS Band : 1900-2025 MHz and 2110-2200 MHz for 3G transmission. • Terrestrial UMTS (UTRAN) : 1900-1980 MHz, 2010-2025 MHz, and 2110-2170 MHz bands
- 24. CDMA2000 evolution to3G IS-95B IS-95B Uses multiple code channels Data rates up to 64kbps Many operators gone direct to 1xRTT 1xRTT CDMA2000 1xRTT: single carrier RTT First phase in CDMA2000 evolution Easy co-existence with IS-95A air interface Release 0 - max 144 kbps Release A – max 384 kbps Same core network as IS-95 1xEV-DO CDMA2000 1xEV-DO: Evolved Data Optimised Third phase in CDMA2000 evolution Standardised version of Qualcomm High Data Rate (HDR) Adds TDMA components beneath code components Good for highly asymmetric high speed data apps Speeds to 2Mbps +, classed as a “3G” system Use new or existing spectrum 1xEV-DV CDMA2000 3xRTT CDMA2000 1x Evolved DV Fourth phase in CDMA2000 evolution Still under development Speeds to 5Mbps+ (more than 3xRTT!) Possible end game. CDMA IS-95A IS-95A 14.4 kbps Core network re- used in CDMA2000
- 25. CDMA 2000 1X •Supports theoretical data rates of up to 307 kbps, with generally experienced rates of 144 kbps. • The newly introduced Q-PCH of CDMA 2000 enables the mobile to be informed about when it needs to monitor F-CCCH and the Paging Channel, thus improving on the battery life • Introduction of Radio Configurations – Transmission formats characterized by physical layer parameters such as data rates, modulation characteristics, and spreading rate. RCs help in providing for additional data rates. • Quality and Erasure indicator bits (QIB and EIB) on the reverse power control sub channel. These help in indicating to the BS about bad frames or lost frames received at the mobile station, so that they can be retransmitted • Code channels are transmitted at full data rates during a data burst • Convolutional and Turbo coding techniques used • Modulation technique used is QPSK
- 26. CDMA 2000 3X •Offering data speeds up to 2 Mbps • Using three standard 1.25 MHz channels within a 5 MHz band • Leveraging deployment experiences, and manufacturers’ learning curves of today’s widely adopted, commercially available CDMA systems • Using Convolutional and Turbo coding techniques • Using QPSK as the Modulation technique
Editor's Notes
- #16 GPRS Tunneling Protocol (GTP) is a group of IP-based communications protocols used to carry General Packet Radio Service (GPRS) within GSM and UMTS networks.
- #19 A virtual private network (VPN) is a computer network that uses a public telecommunication infrastructure such as the Internet to provide remote offices or individual users with secure access to their organization's network.
- #22 Replacing the existing GSM air interface is the final and most important step in the evolution of GSM to UMTS i.e. 3G. Recall that one of the criteria for a system to be IMT2000 compliant is that it implements an air interface standard defined by the ITU. In the case of UMTS, the communication over the air interface, or UMTS Terrestrial Radio Access (UTRA) as it is technically known, is achieved using W-CDMA and TD-CDMA. The access parts of the network, called the UMTS Terrestrial Radio Access Network (UTRAN), are based on ATM and it is here that the major changes in upgrading will occur, which of course will also be reflected on the handsets (figure 4).