GSM_UMTS_Single_RAN_operation_and_Maintenance_training_Volume_2.pptx

Quality and Process-Quality Circle
BSC6910 GU V100R16 product
description

 Upon the completion of this course you will able to
 detail function of the component of BSC6910
Detail hardware structure of BSC6910
 Detail the signal flow in BSC6910
Objective

Network NEs Involved Interface
Name
Interface Type
GSM
between the BSC6910 and
the BTS
Abis Huawei-proprietary
interface, incapable of
interconnecting Huawei
BSC6910 with devices
from another vendor.
Interface between the
BSC6910 and another
BSC
Iur-g Standard interface,
capable of
BSC6910 and the mobile
switching center (MSC) or
the media gateway (MGW)
A
BSC6910 and the serving
GPRS support node
(SGSN)
Gb
BSC6910 and the serving
mobile location center
(SMLC)
Lb
Interface list

Network NEs Involved
Interface
Name Interface Type
UMTS
terface between the
BSC6910 and the NodeB
Iub Standard interface,
capable of
BSC6910 and the RNC
Iur
BSC6910 and another
BSC
Iur-g
BSC6910 and the mobile
switching center (MSC) or
the media gateway (MGW)
Iu-CS
BSC6910 and the SMLC
Iu-PC
Interface list

 The BSC6910 is :
 a new generation product employing a cutting-edge system
architecture.
 can accommodate the growing traffic on the mobile broadband
network, provide diversified services, and support the evolution to
cloud computing.
 can be flexibly configured as a BSC6910 GSM, BSC6910 UMTS,
or BSC6910 GSM+UMTS (GU).
 The BSC6910 GSM or BSC6910 UMTS is referred to as the
BSC6910 in independent mode, and the BSC6910 GU is referred
to as the BSC6910 in integrated mode.
 The BSC6910 GSM and BSC6910 UMTS boards can be installed
in one cabinet.
 supports GU features such as co-operation, administration and
maintenance (co-OAM), co-radio resource management (co-
RRM), and co-transmission resources management (co-TRM).
 can connect to both GSM and UMTS core networks (CNs) and
manages base stations in GSM and UMTS networks.
 can connect to the AC in the WLAN to implement
GSM/UMTS/WLAN (GUW) coordination
BSC6910 Product Description

 The BSC6910 has a modular design and
enhances resource utilization and system reliability
by providing 320 Gbit/s bandwidth for sub rack
interconnection and applying distributed resource
pools to manage service processing units.
 The backplane adopts universalized design.
 It performs different service functions by
connecting various boards so that the university
and evolution capacity of the hardware are
improved.
Architecture

 The BSC6910 uses the
Huawei N68E-22 cabinet
and earthquake-proof
N68E-21-N cabinet.
 The design complies with
the IEC60297 and IEEE
standards. A cabinet
configured with the main
processing sub rack (MPS)
is called main processing
rack (MPR) and a cabinet
not configured with the MPS
is called extended
processing rack (EPR).
Hardware Architecture
1 Subracks 2 Air defector
Front view (left) and rear view
(right) of a BSC6910 cabinet

 In compliance with the
IEC60297 standard, the
BSC6910 sub rack has a
standard width of 19
inches. The height of each
sub rack is 12 U.
 A backplane is positioned
in the center of a sub
rack, with boards on the
front and rear sides of the
backplane.
Subrack
Front view (left) and rear view (right) of the
sub rack
Each sub rack houses 28 slots

Abbreviation Full Name Quantity Function
MPS main
processing
subrack
1 l Performs centralized switching.
l Provides service paths for other
subracks.
l Provides the service processing
interface, system operation management
interface, and system clock interface.
EPS extended
processing sub
rack
0~5 Processes the user plane and control
signaling.
Structure of a sub rack
(1) Front slot (2) Backplane (3) Rear slot

 BSC6910 boards can be classified into
O&M boards,
switching processing boards,
clock processing boards,
general service processing boards,
service awareness boards, and
interface processing boards,
Boards
HW6910 R16 EGPUa, EOMUa, ESAUa, SCUb, SCUc, GCUa, GCUb,
GCGa, GCGb, DPUf, ENIUa, EXOUa, FG2c, FG2d, GOUc,
GOUd, AOUc, UOIc, EXPUa, POUc
HW6910 R17 EGPUa, EGPUb, EOMUa, ESAUa, SCUb, SCUc, GCUa,
GCUb, GCGa, GCGb, DPUf, ENIUa, EXOUa, FG2c, FG2d,
GOUc, GOUd, AOUc, UOIc, EXPUa, POUc, DEUa

Type Board Name Function
General
processing
board
EGPUa Manages user-plane and control-plane resource pools.
Processes user-plane and control-plane services for the
BSC and RNC.
EXPUa Supports multiple functions after the logical board type is
set on the host software.
O&M board
EOMUa
Performs configuration management, performance
management, fault management, security management,
and software loading management for the BSC6910.
Works as the O&M bridge of the LMT/U2000 to provide
the BSC6910 O&M interface for the LMT/U2000 and to
enable communication between the BSC6910 and the
LMT/U2000.
Works as an interface to provide the web-based online
help.
ESAUa
Collects data about the call history record (CHR) and pre-
processes the collected data.
Filters and summarizes raw data of the BSC6910 as
required by the Nastar and uploads the pre-processed
data through the U2000 to the Nastar for analysis.
Classification of BSC6910 boards

Board Type Board
Name
Function
Switching
processing board
SCUb Provides Media Access Control (MAC)/Gigabit
Ethernet (GE) switching and enables the
convergence of asynchronous transfer mode
(ATM) and IP networks.
Provides data switching channels.
Provides system- or subrack-level configuration
and maintenance.
Distributes clock signals for the BSC6910.
SCUc
Clock processing
board
GCUa Obtains the system clock source, performs phase-
lock and holdover, and provides clock signals.
Unlike the GCU board, the GCG board can receive
and process Global Positioning System (GPS)
clock signals.
GCUb
GCGa
GCGb
Service processing
board
DPUf Processes GSM voice services.
Service awareness
board
ENIUa Provides the service awareness function. It works
with the service processing boards to schedule
different types of services.

Board
Type
Board
Name
Function
Interface
processing
board
EXOUa Provides two 10GE optical ports.
Supports IP over GE.
FG2c Provides 12 FE ports or 4 GE electrical ports.
Supports IP over FE/GE.
FG2d Provides 12 FE ports or 4 GE electrical ports.
Supports IP over FE/GE.
GOUc Provides four GE optical ports.
GOUd Provides four GE optical ports.
GOUe Provides four GE optical ports.
GOUd Provides four GE optical ports.
GOUe Provides four GE optical ports.
AOUc Provides four ATM over Channelized Optical STM-1/OC-3 ports.
Supports ATM over E1/T1 over SDH/SONET.
Provides 252 E1s or 336 T1s.
Extracts clock signals and sends the signals to the GCUa/GCUb or
GCGa/GCGb board.

Board
Type
Board
Name
Function
Interface
processing
board
UOIc Provides eight unchannelized STM-1/OC-3c ports.
Supports ATM over SDH/SONET.
Extracts clock signals and sends the signals to the
GCUa/GCUb or GCGa/GCGb board.
POUc Provides four TDM/IP over Channelized Optical STM-1/OC-3
ports.
Supports IP over E1/T1 over SDH/SONET.
Supports a bearer capability equivalent to 252 E1s or 336 T1s.
Extracts clock signals and sends the signals to the
GCUa/GCUb or GCGa/GCGb board.

 Boards in the BSC6910 GU can be configured as different
logical types by software to perform different functions
Configuration of a Subrack and Principles for Installing
Boards…
Configuration of a Subrack
The MPS is configured in the MPR. Each BSC6910 cabinet must be configured
with one MPS Configuration of the MPS (Configured with SCUb

Boards…
The MPS is configured in the MPR. Each BSC6910 cabinet must be configured
with one MPS
Configuration of the MPS (Configured with SCUC

Boards…
Configuration of the EPS (The EPS is configured in the MPR or EPR)
Configuration of the EPS (Configured with SCUb)

Boards…
Configuration of the EPS (Configured with SCUc)
The EPS is configured in the MPR or EPR

Boards…
Principles for Installing Boards
Switching Board
 SCUb/SCUc boards must be installed in slots 20 and 21.
Clock Board
GCUa, GCUb, GCGa, GCGb boards must be installed in slots 14 and 15 in
the MPS.
OM Board
EOMUa boards can be installed in slots 0, 2, 4, 6, 10, 12, 25 and 27 in the MPS.
It is recommended that EOMUa boards be installed in slots 10 and 12 of the
MPS subrack.
Service Processing Board
 The EGPUa/EGPUb boards of the RMP logical type are installed in slots 8 and
9 in the MPS
 EGPUa/EGPUb/EXPUa/EXPUb boards can be installed in slots other than
those for the SCUb/SCUc, GCUa/GCUb/GCGa/GCGb, and EOMUa/ESAUa
boards. EGPUa/EGPUb/EXPUa/EXPUb boards are preferentially installed in
slots 0 to 13.

Boards…
Interface Board
 Interface boards must be installed in the rear slots of a subrack to facilitate cable
layout
 The FG2c, GOUc/GOUe, FG2d, GOUd, POUc boards support large throughput.
 The boards are preferentially installed in slots 16 to 19 and 22 to 25.
 If these slots are occupied, the boards can be installed in slots 14 to 15 and
26 to 27.
 The IuPS interface boards that carry IP transmission are preferentially
installed in slots 16 to 19 and 22 to 25
 The AOUc, UOIc boards support small throughput.
 The boards are preferentially installed in slots 14 to 15 and 26 to 27.
 If these slots are occupied, the boards can be installed in slots 16 to 19 and
22 to 25.
 If the SCU board in a subrack is SCUb,
 the EXOUa board must be installed in slots 16 to 19 and 22 to 25 in the
subrack.
 If the SCU board in the subrack is SCUc,
 the EXOUa board in the basic subrack can be installed in slots 16 to 19 and
22 to 27, and the EXOUa board in the extension subrack can be installed in
slots 14 to 19 and 22 to 27

Boards…
Data Processing Board
 The DPUf board can be installed in slots other than those for the SCUb/SCUc
or GCUa/GCUb/GCGa/GCGb board.
 It is recommended that the DPUf board be installed in a slot among slots
0 to 13.
 The DEUa board can be installed in slots other than those for the
SCUb/SCUc or GCUa/GCUb/GCGa/GCGb board.
 It is recommended that the DEUa board be installed in a slot among
slots 0 to 13.

 The BSC6910 inherits the layered
software architecture of the
BSC6900.
 By deploying different application
software on a unified base
platform, the BSC6910 provides
different services.
 Each layer and each plane are
deployed on its lower layer and
provide services for its upper
layer and other planes.
 At the same time, the technical
implementation of each layer,
such as algorithms and physical
deployment, is isolated from other
layers so that each layer and
each plane are dedicated to its
own functions and evolve
independently
Software Architecture

BSC6910 software architecture
Plane Function
Base platform Provides the operating system (OS) and basic
functions, such as cross-process communication,
message management, redundant backup, and
software management.
OM mechanism plane Provides O&M functions for the system, and
provides communication with the network
management system (NMS) through the
southbound interface.
Application OM plane Provides configuration management, maintenance
management, performance management, alarm
management, and log management for the
system.
Resource management
plane
Manages user plane, control plane, and transport
plane resources.
Function plane Processes GSM and UMTS call services
according to 3GPP specifications.

 The BSC6910 system reliability design is characterized by:
 System Reliability
• High-reliability architecture
 The port trunking technology is employed on active and
standby switching boards.
 The ports in a port trunking group work in load sharing mode.
 When a link between the SCUb boards in different sub racks
becomes faulty, the system transfers the services carried on
the faulty link to other links and isolates the faulty link.
 In addition, the SCUb boards in different sub racks are cross-
connected, preventing a port failure on the SCUb board in
one sub rack from affecting the SCUb boards in another sub
rack.
 This improves reliability of intra-system communication.
 Dual planes are used in clock transmission between the
GCUa/GCUb/GCGa/GCGb board and the SCUb board.
 Therefore, a single point of failure (SPOF) does not affect the
normal operation of the system clock
System Reliability

 Resource pool design
 In case of overload, the system implements load sharing on the control
plane and on the user plane by employing a resource pool design.
 This effectively prevents resource suspension caused by an overload,
improving resource usage efficiency and system reliability.
 Active/standby switchover
 All BSC6910 hardware uses a redundancy mechanism.
 A rapid switchover between active and standby parts improves system
reliability.
 In addition, with a quick fault detection and recovery mechanism, the
impact of faults on services is minimized
 Flow control
 The system performs flow control based on the CPU and memory
usage.
 The BSC6910 can continue working by regulating the items pertaining
to performance monitoring, resource auditing, and resource scheduling
in the case of CPU overload and resource insufficiency.
 In this way, system reliability is enhanced.
System Reliability

Board Redundancy Mode
EGPUa Board resource pool
EXOUa Board redundancy + board resource pool + 10 GE port
redundancy or load sharing
EOMUa Board redundancy
ESAUa Independently configured
FG2c/FG2d Board redundancy + board resource pool + GE/FE port
GOUc/GOUd/GOUe Board redundancy + board resource pool + GE port
AOUc Board redundancy + MSP 1:1 or MSP 1+1 optical port
redundancy
DPUf Board resource pool
UOIc Board redundancy + MSP 1:1 or MSP 1+1 optical port
redundancy
POUc Board redundancy + MSP 1:1 or MSP 1+1 optical port
redundancy
GCUa/GCUb/GCGa/GCGb Board redundancy
SCUb/SCUc Board redundancy + port trunking on GE ports
ENIUa Board resource pool
Hardware Reliability

Scheduled checks on critical resources
 A software check mechanism checks various software resources in the system. If
resources are out of service due to software faults, this mechanism can release
abnormal resources and generate related logs and alarms.
Task monitoring
 When software is running, a monitoring process monitors internal software faults
and some hardware faults. The monitoring process then reports the status or
errors, of running tasks, to the O&M system.
Data checking
 A software integrity check and digital signature are used to prevent software from
being tampered with during transmission and storage.
 The software performs scheduled or event-driven data consistency checks,
restores data selectively or preferably, and generates logs and alarms.
Data backup
 Both the data in the OMU database and the data of other boards can be backed up
to ensure data reliability and consistency.
Operation log storage
 The system automatically logs operations. These operation logs help users locate
and rectify faults caused by misoperations.

Software Reliability

 The BSC6910 GSM or BSC6910 UMTS is referred to as the
BSC6910 in independent mode, and the BSC6910 GU is
referred to as the BSC6910 in integrated mode.
 The BSC6910 GU incorporates the functions of the BSC6910
GSM and BSC6910 UMTS through unified software
management and shared EOMU and GCU/GCG.
 In the BSC6910 GU, GSM service boards and UMTS service
boards are configured in separate subracks
 The BSC6910 GU and BSC6910 UMTS each supports a
maximum of two cabinets accommodating six subracks, while
the BSC6910 GSM supports a maximum of one cabinet
accommodating three subracks.
 In GU mode, GSM services can be configured in a maximum
of three subracks.
Configurations

Example of the configurations of the BSC6910
UMTS, BSC6910 GSM, and BSC6910 GU

Parameter Value
voice traffic /sub/BH (Erlang) 0.02
voice call duration (seconds) 60
percent of Mobile originated calls 50%
percent of Mobile terminated calls 50%
average LUs/sub/BH 1.2
average IMSI Attach/sub/BH 0.15
average IMSI Detach/sub/BH 0.15
average MOCs/sub/BH 0.6
average MTCs/sub/BH 0.6
MR report/sub/BH 144
average MO-SMSs /sub/BH 0.6
average MT-SMSs /sub/BH 1
average intra-BSC HOs /sub/BH 1.1
average inter-BSC HOs /sub/BH 0.1
paging retransfer /sub/BH 0.56
Grade of Service (GoS) on Um interface 0.01
Grade of Service (GoS) on A interface 0.001
percent of HR (percent of Um interface resources occupied by HR voice
call)
50%
Uplink TBF Est & Rel / Second/TRX 1.75
Downlink TBF Est & Rel / Second/TRX 0.9
PS Paging / Sub/BH 1.25
Capacity Configuration of the BSC6910 GSM

Name Typical Configuration
Number of subracks 1
Maximum number of TRXs 1024
Maximum number of
equivalent BHCA (k)
2200
Maximum traffic volume
(Erlang)
6250
Maximum number of
activated PDCHs (MCS-9)
4096
Capacity of a BSC6910 GSM in Abis over TDM, A over
TDM, and Gb over IP modes

Number of sub racks 1
Maximum number of TRXs 3,000
Maximum number of equivalent
BHCA (k)
6,500
Maximum traffic volume (Erlang) 18,750
Maximum number of activated
PDCHs (MCS-9)
12,000
Capacity of a BSC6910 GSM in Abis over TDM, A over IP, and
Gb over IP modes

BHCA (k)
6500
Maximum traffic volume (Erlang) 18750
PDCHs (MCS-9)
12000
Capacity of a BSC6910 GSM in all-IP transmission
mode

BHCA (k)
8668
Maximum traffic volume (Erlang) 25000
PDCHs (MCS-9)
16000
Capacity of a BSC6910 GSM in all-IP transmission mode
with BSC Node Redundancy

 The BSC6910 UMTS supports the flexible configuration of
control plane and user plane data in different scenarios. In
each scenario, the capacity configured for the BSC6910
UMTS depends on actual traffic models.
 There are two traffic models for the BSC6910 UMTS:
 High-PS traffic model: Subscribers use much more data
services than voice services. In this model, the average PS
throughput per user is high.
 Smartphone traffic model: Smartphones are widely used.
CP signaling is frequently exchanged and UP data is
transmitted mainly through small-sized packets.
Capacity Configuration of the BSC6910 UMTS

Name Specification Description
CS voice traffic volume 3 mE 0.144 BHCA, AMR voice service
CS data traffic volume 0.2 mE 0.01 BHCA, UL: 64 kbit/s, DL: 64
kbit/s
PS throughput 43500 bit/s 3 BHCA, UL: 64 kbit/s, DL: 384
kbit/s
Proportion of soft handovers 30% Proportion of calls using two
channels simultaneously to all calls
Handover times per CS call (SHO)
(times/call)
8 N/A
Handover times per PS call (SHO)
(times/call)
5 N/A
NAS signaling per subscriber per
BH (times)
3.6 Number of NAS procedures
between the CN and UEs, including
location area updates, IMSI
attach/detach occurrences, routing
area updates, GPRS attach/detach
occurrences, and SMSs
Iur-to-Iub traffic ratio 8% N/A
High-PS traffic model

Subscribers
Supported
CS
Service
Capacit
y
(Erlang)
PS Service
Capacity
(Iub
UL+DL)
(Mbit/s)
BHCA
(k)
Number of
Active
Users
Number
of Online
Users
Number of
Subrack
Combinati
on
1,380,000 5,700 59,500 4,300 210,000 420,000 1 MPS +
2 EPSs
2,760,000 11,400 120,000 8,600 420,000 840,000 1 MPS +
5 EPSs
Typical capacity of the BSC6910 UMTS under
high-PS traffic model (HW6910 R16)

Item Specification Description
Voice Traffic per CS voice
subscriber in BH
30 mE 0.7 BHCA, AMR voice service
PS throughput 1600 bit/s 8 BHCA
Proportion of soft handovers 34% Proportion of calls using two
channels simultaneously to all calls
Handover times per CS call (SHO)
(times/call)
4 N/A
Handover times per PS call (SHO)
(times/call)
1 N/A
Inter-PDCH handovers per PS call 2.3 Including all handovers between
different connected RRC states and
transmission channels per PS call
NAS signaling per subscriber per
BH (times)
2.8 Number of NAS procedures between
the CN and UEs, including location
area updates, IMSI attach/detach
occurrences, routing area updates,
GPRS attach/detach occurrences,
and SMSs
Iur-to-Iub traffic ratio 8% N/A
Traffic model for smart phones

Subscribers
Supported
CS Voice
Service
Capacity
(Erlang)
PS Service
Capacity (Iub
UL+DL)
(Mbit/s)
BHCA (k) Number
of Active
Users
Number of
Online
Users
Number
of
Subrack
Combinat
ion
3,600,000 122,000 5,800 32,000 665,000 1,000,000 1 MPS +
2 EPSs
7,490,000 250,000 11,900 64,000 1,000,000 1,000,000 1 MPS +
5 EPSs
Typical capacity of the BSC6910 UMTS under
smartphone traffic model (HW6910 R16)

Typical
Configuration/Specifica
tions
1 MPS
(GSM)+2 EPSs
(UMTS)
GSM in All-IP
Mode
1 MPS (GSM)+1
EPS (GSM)+1 EPS
(UMTS)
GSM in All-IP Mode
1 MPS (UMTS)+2
EPSs (GSM)
GSM in All-IP Mode
1 MPS (UMTS)+1
EPS (UMTS)+1
EPS (GSM)
GSM in All-IP Mode
Maximum UMTS traffic
volume (Erlang)
83,750 40,000 40,000 83,750
Maximum UMTS PS
(UL+DL) data
throughput (Mbit/s)
40,200 19,200 19,200 40,200
Maximum number of
GSM TRXs
6000 15,000 18,000 9000
Maximum number of
equivalent BHCA for
GSM (k)
13,000 32,500 39,000 19,500
Maximum number of
active PDCHs for GSM
(MCS-9)
24,000 60,000 72,000 36,000
Maximum GSM traffic
volume (Erlang)
37,500 93,750 112,500 56,250
Capacity configuration of the BSC6910 GU

BSC6910 GU Technical Description
Logical Structure
Logically, the BSC6910 consists of the following subsystems: the
switching subsystem (MAC switching), service processing subsystem
(RNC RAT/BSC RAT), interface processing subsystem (ATM/TDM/IP
interface board), clock synchronization subsystem, and O&M subsystem
(OMU board).
Signal Flow
The BSC6910 signal flow consists of the user-plane signal flow, control-
plane signaling flow, and O&M signal flow.
Transmission and Networking
The transmission and networking between the BSC6910 and other NEs
can be classified into the following types: transmission and networking on
the A/Gb interface, on the Abis interface, on the Iub interface, and on the
Iu/Iur interface.
Reliability
The BSC6910 guarantees its operation reliability using board redundancy
and port redundancy.

 Logically, the BSC6910 consists of the following
subsystems:
the switching subsystem (MAC switching),
 service processing subsystem (RNC RAT/BSC
RAT),
 interface processing subsystem (ATM/TDM/IP
interface board),
clock synchronization subsystem, and
 O&M subsystem (OMU board).
Logical Structure

 The switching subsystem performs switching of traffic data,
signaling, and O&M signals of the BSC6910.
Switching Subsystem
Functions
 Intra-subrack MAC switching
 Inter-subrack MAC switching
 Distribution of clock signals and RNC frame number
(RFN) signals among service processing boards
SCUb-base Inter-Subrack Connection
 The SCUb in a sub rack provides four 10GE ports for inter-subrack connection.
 There is a connection between every two adjacent nodes.
 If an intermediate node is out of service, the communication between other
nodes is affected.
 If three or fewer sub racks are configured, they are connected in a star
topology.
 The MPS and two EPSs in the MPR are connected in a star topology.
 In the star topology, the MPS functions as the basic sub rack and the EPSs
function as extension sub racks.
 The EPSs in the MPR and the EPSs in the EPR are connected in a chain
topology.

 Functions
The service processing subsystem performs the following
functions:
User data transfer
System admission control
Radio channel encryption and decryption
Data integrity protection
Mobility management
Radio resource management and control
Cell broadcast service control
System information and user information tracing
Data volume reporting
Radio access management
CS service processing
PS service processing
Service Processing Subsystem

 Functions
 The interface processing subsystem provides the following
ATM/TDM/IP interfaces:
 Channelized STM-1/OC-3 optical ports
 Unchannelized STM-1/OC-3 optical ports
 FE/GE electrical ports
 GE optical ports
 10GE optical ports
 The interface processing subsystems processes transport-
layer and network-layer messages and hides differences
between them.
 In the uplink, the interface processing subsystem terminates
the transmission of transport-layer and network-layer
messages on the interface boards.
 It also transmits the UP, CP, and management plane
packets to the corresponding service processing boards.
The downlink signal flow is the reverse of the uplink signal
flow.
Interface Processing Subsystem

 BITS Clock
 BITS clock signals consist of 2 MHz, 2 Mbit/s, and 1.5 Mbit/s
clock signals. 1.5 Mbit/s clock signals are T1 clock signals. 2
MHz and 2 Mbit/s are E1 clock signals. 2 MHz is intended for
electrical impulse, and 2 Mbit/s is intended for data flow.
 The BITS clock has two inputs: BITS1 and BITS2. BITS1 and
BITS2 correspond to the CLKIN0 and CLKIN1 ports on the
GCUa/GCUb/GCGa/GCGb board, respectively. The
BSC6910 obtains the BITS clock signals through the CLKIN0
or CLKIN1 port.
 External 8 kHz Clock
 Through the COM1 port on the GCUa/GCUb/GCGa/GCGb
board, the BSC6910 obtains 8 kHz standard clock signals
from an external device.
 LINE Clock
 The LINE clock is an 8 kHz clock that is transmitted from an
interface board in the MPS to the GCUa/GCUb/GCGa/GCGb
board through the backplane channel. The LINE clock has
two input modes: LINE1 and LINE2.
Clock Sources

 The clock synchronization subsystem consists of the
clock board, backplanes, clock cables between subracks,
and clock module in each board.
Structure of the Clock Synchronization Subsystem

 The structure of the BSC6910 clock synchronization
subsystem is described as follows:
The structure of the BSC6910 clock
synchronization subsystem is described as follows:
 The BSC6910 clock board can be the GCUa/GCUb/GCGa/GCGb board.
 The BSC6910 cannot be configured with both the GCUa/GCUb and
GCGa/GCGb boards.
 It can be configured with only the GCUa/GCUb board or the GCGa/GCGb
board, depending on the clock type.
 The BSC6910 only supports that the MPS extracts the clock signals. The
clock signals enter the MPS in any of the following ways:
 The clock signals enter the port on the panel of the
GCUa/GCUb/GCGa/GCGb board.
 The clock signals enter the port on the panel of an interface board that
can extract line clock signals, include AOUc/POUc/UOIc board. The
clock signals are then switched to the GCUa/GCUb/GCGa/GCGb board
through the backplane.
 The GCUa/GCUb/GCGa/GCGb board generates oscillator clock
signals.

Structure of the Clock Synchronization Subsystem
 Connections of the
clock cables between
the clock boards in
the MPS and the SCU
boards in the EPS
 The active and standby clock
boards in the MPS are
connected to the active and
standby SCU boards in the
EPS through the Y-shaped
clock signal cables.
 This connection mode ensures
that the system clock of the
BSC6910 works properly in the
case of a single-point failure of
the clock board, Y-shaped clock
signal cable, or SCU board.

 Clock Synchronization in the MPS/EPS
 The MPS/EPS reference clock signals are provided by the clock
board.
 The clock board can extract clock signals from an external device or
extract LINE clock signals from the Iu-CS interface.
 The GCGa/GCGb board can also extract clock signals from the
GPS.
Clock Synchronization Process

The process of clock synchronization in the MPS/EPS is as
follows:
1.If an external clock is used, external clock signals travel to the clock board through
the port on the panel of the clock board. If the GPS clock is used, clock signals travel
to the clock board through the GPS antenna port. If the LINE clock is used, clock
signals travel to the clock board through the backplane.
2.The clock source is phase-locked in the clock board to generate clock signals. The
clock signals, then, are sent to the SCU board in the MPS through the backplane and
to the SCU board in each EPS through the clock signal output ports.
3.The SCU board in the MPS/EPS transmits the clock signals to other boards in the
same subrack through the backplane

A phase-locked loop (PLL)
•Free Running
• If no reference clock source is configured or the reference clock sources are
unavailable, the PLL works in the Free Running state.
• If there's an available reference clock source, the BSC judges the reference clock
source for 260 seconds. If the source remains stable for more than 260 seconds,
the PLL shifts to the Quick Capture state. Otherwise, the PLL remains in the Free
Running state.
•Quick Capture
• If the reference clock source is available and remains stable for a period (400
seconds for a GPS source or 200 seconds for any source other than GPS), the PLL
shifts to the Lock state.
• If the reference clock source is lost, the PLL shifts back to the Free Running state.
•Lock
• If the reference clock source is lost when the lock has been started for more than
600 seconds, the PLL shifts to the Hold state.
• If the reference clock source is lost within 600 seconds after the lock is started, the
PLL shifts back to the Free Running state.
•Hold
• If there's still no reference clock source available 10 days after the PLL shifts to the
Hold state, the PLL shifts back to the Free Running state.
• If other reference clock source is available, or the reference clock source recovers
within 10 days and remains stable for more than 260 seconds, the PLL shifts to the
Quick Capture state.

 The O&M subsystem enables management and
maintenance in the following scenarios:
 Routine maintenance, emergency maintenance,
upgrades, and capacity expansion.
It enables management in data configuration,
security, performance, alarm, loading, and upgrade.
The O&M subsystem consists of the EOMUa board
O&M Subsystem
Dual O&M Plane

 The internal network and external network should be on different network
segments to ensure that the two networks are isolated.
 The dual O&M plane design is implemented by the hardware
that works in active/standby mode.
 When an active component is faulty but the standby
component works properly, a switchover is automatically
performed between the active and standby components, to
ensure that the O&M channel works properly.
 The active/standby OMU boards use the same external virtual
IP address to communicate with the LMT or U2000 and use the
same internal virtual IP address to communicate with the SCU
boards.
 When the active OMU board is faulty, an active/standby
switchover is performed automatically, and the standby OMU
board takes over the O&M task. In this case, the internal and
external virtual IP addresses remain unchanged.
 This ensures the proper communication between the internal
and external networks of the BSC6910.
 When a single-point failure occurs on the switching network,
the active/standby SCU boards in each subrack are switched
over automatically. This ensures that the O&M channel works
properly.
Dual O&M Plane

 The O&M network of the BSC6910 consists of the U2000,
LMT, OMU, SCU boards, and O&M modules in other
boards.
O&M Network

U2000
The U2000 is a centralized network management system. The U2000 is connected to the BSC6910
through Ethernet cables. One U2000 can remotely manage multiple BSCs (BSC6910).
The main operation, administration, and maintenance entity of the BSC6910 is the U2000 or U2000 UI.
LMT
The LMT is connected to the EOMUa board of the BSC6910. One or multiple LMTs can be connected
to the EOMUa board directly or through networks. The maintenance of the BSC6910 can be performed
locally or remotely through the LMT. The LMT is connected to an alarm box through a serial cable.
EOMUa Board
The EOMUa board is the back administration module of the BSC6910. It is connected to an external
device through the Ethernet cable. The BSC6910 can be configured with one EOMUa board in
independent mode or with two EOMUa boards in active/standby mode.
The EOMUa board functions as a bridge between the BSC6910 and the LMT or U2000. The O&M
network of the BSC6910 is classified into the following networks:
•Internal network: implements the communication between the EOMUa board and the host
boards of the BSC6910.
•External network: implements the communication between the EOMUa board and external
devices, such as the LMT or U2000.
SCU Board
The SCU board is the switching and control board of the BSC6910. It is responsible for the O&M of the
subrack where it is located. If a subrack is configured with two SCU boards, then the two boards work
in active/standby mode.
The SCU board performs O&M on other boards in the same subrack through the backplane channels.
The SCU boards in different subracks are connected through crossover cables

 The data configuration management involves managing the data
configuration process of the BSC6910 so that configuration data is
successfully sent to the related boards.
Data Configuration Management
Data Configuration Modes
The BSC6910 supports two data configuration modes: effective mode and
ineffective mode.
 If data configuration is performed on the BSC6910 in effective mode, the
configuration data takes effect on the host boards in real time.
 If data configuration is performed on the BSC6910 in ineffective mode, the
configuration data takes effect only after the BSC6910 is switched to the
effective mode and is reset.
The process of configuration in effective mode is as
follows:
1.The BSC6910 is switched to the effective
mode.
2.The LMT or U2000 sends MML commands to
the configuration management module of the
OMU.
3.Upon receiving the MML commands, the
configuration management module of the OMU
sends the configuration data to the database of
the related host board and writes the data to the
OMU database.

Configuration in ineffective mode
Configuration in ineffective mode is applied to BSC6910 initial configuration.
The process of configuration in
ineffective mode is as follows:
1.The BSC6910 is switched to the
ineffective mode.
2.The LMT or U2000 sends MML
commands to the configuration
management module of the OMU.
3.Upon receiving the MML
commands, the configuration
management module sends only
the configuration data included in
the MML commands to the OMU
database.
4.When a sub rack or the BSC6910
is reset, the OMU formats the
configuration data in the database
into a .dat file, loads the file onto
the related host boards, and then
activates the configuration data.

Data Configuration Check
Data validity check
The data validity check checks whether a configuration complies with the
configuration rules and whether an MML script file complies with the syntactic
rules.
When a configuration is performed or an MML command is executed, the data
validity check is performed. If an error is detected, the BSC6910 stops performing
the configuration or running the command. At the same time, a warning message
is displayed.
Data consistency check
The data consistency check consists of two parts:
Checking data consistency between the active and standby OMUs
If the BSC6910 is configured with the active and standby OMUs, the data on the
active OMU must be the same as that on the standby OMU to ensure BSC6910
reliability. If a data consistency is detected, an active/standby switchover cannot
be performed when the active OMU becomes faulty.
Checking data consistency between the OMU and host boards
The data on the host boards must be the same as that on the OMU. Otherwise,
the system cannot run stably. In addition, some data modified by users cannot
take effect

Data Configuration Modes
The procedure for checking data consistency between the OMU and host boards
is as follows:
1.On the LMT, a data consistency check command is sent to the OMU
automatically on a regular basis or manually.
2.The OMU analyzes the parameters of the command and checks whether
the data in the board databases is the same as that in the OMU database.
3.The OMU generates a result file and sends it to the LMT.

GSM_UMTS_Single_RAN_operation_and_Maintenance_training_Volume_2.pptx

Recommended

Recommended

More Related Content

What's hot

What's hot (20)

Similar to GSM_UMTS_Single_RAN_operation_and_Maintenance_training_Volume_2.pptx

Similar to GSM_UMTS_Single_RAN_operation_and_Maintenance_training_Volume_2.pptx (20)

More from hussenbelew

More from hussenbelew (13)

Recently uploaded

Recently uploaded (20)

GSM_UMTS_Single_RAN_operation_and_Maintenance_training_Volume_2.pptx