bsc6900 gsm technical description-(v900r011c00_03)

7/29/2019 BSC6900 GSM Technical Description-(V900R011C00_03)

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BSC6900 GSM

V900R011C00

Technical Description

Issue 03

Date 2009-12-05

Huawei Proprietary and Confidential

Copyright Huawei Technologies Co., Ltd.


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Huawei Technologies Co., Ltd. provides customers with comprehensive technical support and service. For any

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Huawei Technologies Co., Ltd.

Address: Huawei Industrial Base

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Copyright Huawei Technologies Co., Ltd. 2009. All rights reserved.

No part of this document may be reproduced or transmitted in any form or by any means without prior written

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and other Huawei trademarks are the property of Huawei Technologies Co., Ltd.

All other trademarks and trade names mentioned in this document are the property of their respective holders.

Notice

The purchased products, services and features are stipulated by the contract made between Huawei and the

customer. All or part of the products, services and features described in this document may not be within the

purchase scope or the usage scope. Unless otherwise specified in the contract, all statements, information,

and recommendations in this document are provided "AS IS" without warranties, guarantees or representations

of any kind, either express or implied.

The information in this document is subject to change without notice. Every effort has been made in the

preparation of this document to ensure accuracy of the contents, but all statements, information, andrecommendations in this document do not constitute the warranty of any kind, express or implied.

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Contents

About This Document.....................................................................................................................1

1 Changes in BSC6900 GSM Technical Description..............................................................1-1

2 Hardware Configuration Modes.............................................................................................2-1

3 Overall Structure........................................................................................................................3-1

3.1 Switching Subsystem.............................................................................. ........................................................3-5

3.2 Service Processing Subsystem........................................................................................................................3-9

3.3 Interface Processing Subsystem....................................................................................................................3-10

3.4 Clock Synchronization Subsystem................................................................................................................3-12

3.5 OM Subsystem..............................................................................................................................................3-13

4 Working Principles....................................................................................................................4-1

4.1 Power Supply Principle...................................................................................................................................4-2

4.2 Environment Monitoring Principle.................................................................................................................4-34.3 Clock Synchronization Principle.....................................................................................................................4-6

4.3.1 Clock Sources.........................................................................................................................................4-6

4.3.2 Structure of the Clock Synchronization Subsystem...............................................................................4-7

4.3.3 Clock Synchronization Process..............................................................................................................4-9

4.4 OM Principle.................................................................................................................................................4-10

4.4.1 Dual OM Plane.....................................................................................................................................4-11

4.4.2 OMNetwork............................................................................ ............................................................4-12

4.4.3 Active/Standby Workspaces................................................................................................................4-14

4.4.4 Data Configuration Management.........................................................................................................4-16

4.4.5 Security Management...........................................................................................................................4-19

4.4.6 Performance Management....................................................................................................................4-23

4.4.7 Alarm Management..............................................................................................................................4-24

4.4.8 Loading Management...........................................................................................................................4-26

4.4.9 Upgrade Management..........................................................................................................................4-30

4.4.10 BTS Loading Management................................................................................................................4-32

4.4.11 BTS Upgrade Management................................................................................................................4-33

5 Signal Flow..................................................................................................................................5-1

5.1 User-Plane Signal Flow...................................................................................................................................5-2

5.1.1 CBC Signal Flow...................................................................................................................................5-2

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5.1.2 GSM CS Signal Flow.............................................................................................................................5-3

5.1.3 GSM PS Signal Flow.............................................................................................................................5-8

5.2 Control-Plane Signal Flow............................................................................................................................5-10

5.2.1 Signaling Flow on the A Interface.......................................................................................................5-10

5.2.2 Signaling Flow on the Abis Interface...................................................................................................5-12

5.2.3 Signaling Flow on the Gb Interface.....................................................................................................5-14

5.2.4 Signaling Flow on the Pb Interface......................................................................................................5-14

5.3 OM Signal Flow............................................................................................................................................5-15

6 Transmission and Networking................................................................................................6-1

6.1 Transmission and Networking on the A/Gb Interface.....................................................................................6-2

6.1.1 TDM-Based Networking on the A/Gb Interface....................................................................................6-2

6.1.2 IP-Based Networking on the A/Gb Interface.........................................................................................6-3

6.2 Transmission and Networking on the Abis Interface......................................................................................6-4

6.2.1 TDM-Based Networking on the Abis Interface.....................................................................................6-4

6.2.2 IP-Based Networking on the Abis Interface...........................................................................................6-5

6.3 Transmission and Networking on the Ater Interface......................................................................................6-7

6.3.1 TDM-Based Networking on the Ater Interface......................................................................................6-7

6.3.2 IP-Based Networking on the Ater Interface...........................................................................................6-8

6.4 Transmission and Networking on the Pb Interface.........................................................................................6-8

Contents

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Figures

Figure 3-1 Structure of the host software.............................................................................................................3-2

Figure 3-2 Structure of the OMU software..........................................................................................................3-2

Figure 3-3 Logical structure of MPS/EPS............................................................................................................3-3

Figure 3-4 Logical structure of TCS....................................................................................................................3-3

Figure 3-5 Position of the switching subsystem in the MPS/EPS........................................................................3-5

Figure 3-6 Position of the switching subsystem in the TCS................................................................................3-6

Figure 3-7 Network topologies between subracks...............................................................................................3-7

Figure 3-8 Interconnections between subracks through the crossover cables between the SCUa boards (MPS/EPS)

...............................................................................................................................................................................3-7

Figure 3-9 Interconnections between subracks through the crossover cables between the SCUa boards (TCS)

...............................................................................................................................................................................3-8

Figure 3-10 Interconnections between subracks through the inter-TNUa cables (MPS/EPS).............................3-8

Figure 3-11 Interconnections between subracks through the inter-TNUa cables (TCS).....................................3-9

Figure 3-12 Service processing subsystem..........................................................................................................3-9

Figure 3-13 Position of the interface processing subsystem in the MPS/EPS...................................................3-11

Figure 3-14 Position of the interface processing subsystem in the TCS............................................................3-11

Figure 3-15 Position of the clock synchronization subsystem in the BSC6900 system....................................3-12

Figure 3-16 Position of the OM subsystem in the BSC6900 system.................................................................3-13

Figure 4-1 Power input part of the BSC6900.......................................................................................................4-2

Figure 4-2 Working principle of power monitoring.............................................................................................4-3

Figure 4-3 Working principle of fan monitoring..................................................................................................4-4

Figure 4-4 Working principle of environment monitoring...................................................................................4-5

Figure 4-5 Structure of the clock synchronization subsystem..............................................................................4-7

Figure 4-6 Structure of the clock synchronization subsystem..............................................................................4-8Figure 4-7 Process of clock synchronization in the MPS/EPS (1).......................................................................4-9

Figure 4-8 Process of clock synchronization in the MPS/EPS (2).......................................................................4-9

Figure 4-9 Process of clock synchronization in the TCS...................................................................................4-10

Figure 4-10 Dual OM plane...............................................................................................................................4-12

Figure 4-11 Structure of the OM network..........................................................................................................4-13

Figure 4-12 Principle of effective mode configuration......................................................................................4-16

Figure 4-13 Principle of ineffective mode configuration...................................................................................4-17

Figure 4-14 Check of the data consistency between the OMU and the host boards..........................................4-19

Figure 4-15 Process of collecting performance measurement data periodically................................................4-23

Figure 4-16 Alarm management process............................................................................................................4-25

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Figure 4-17 Working principle of the alarm box................................................................................................4-26

Figure 4-18 Loading process (1)........................................................................................................................4-27



Figure 4-21 Upgrade through the OM network..................................................................................................4-30

Figure 4-22 Upgrade process.............................................................................................................................4-31

Figure 5-1 Signal flow from CBC-BSC to Abis.................................................................................................. 5-2

Figure 5-2 GSM CS signal flow (1).....................................................................................................................5-3








Figure 5-10 GSM PS signal flow (1)....................................................................................................................5-9

Figure 5-11 GSM PS signal flow (2)....................................................................................................................5-9

Figure 5-12 Signaling flow on the A interface in A over TDM mode (BM/TC separated)...............................5-11

Figure 5-13 Signaling flow on the A interface in A over TDM mode (BM/TC combined)..............................5-11

Figure 5-14 Signaling flow on the A interface in A over IP mode....................................................................5-12

Figure 5-15 Signaling flow on the Abis interface in Abis over TDM mode......................................................5-13

Figure 5-16 Signaling flow on the Abis interface in Abis over IP mode...........................................................5-13

Figure 5-17 Signaling flow on the Gb interface.................................................................................................5-14Figure 5-18 Signaling Flow on the Pb interface.................................................................................................5-15

Figure 5-19 OM signal flow (BM/TC separated)...............................................................................................5-16

Figure 5-20 OM signal flow (BM/TC combined)..............................................................................................5-17

Figure 6-1 TDM-based networking on the A interface in local TCS mode.........................................................6-2

Figure 6-2 TDM-based networking on the A interface in remote TCS mode......................................................6-2

Figure 6-3 TDM-based networking on the Gb interface......................................................................................6-3

Figure 6-4 IP over E1 networking on the A interface..........................................................................................6-3

Figure 6-5 IP over Ethernet networking on the A/Gb interface...........................................................................6-4

Figure 6-6 TDM-based networking on the Abis interface................................................................................... 6-5

Figure 6-7 IP over E1 Networking.......................................................................................................................6-5

Figure 6-8 IP over Ethernet networking (layer 2)................................................................................................6-6

Figure 6-9 IP over Ethernet networking (layer 3)................................................................................................6-6

Figure 6-10 TDM-based networking on the Ater interface..................................................................................6-7

Figure 6-11 IP-based networking on the Ater interface.......................................................................................6-8

Figure 6-12 TDM-based networking on the Pb interface.....................................................................................6-8

Figures

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Tables

Table 3-1 Components of the BSC6900 cabinet..................................................................................................3-1

Table 4-1 Definitions of the user rights..............................................................................................................4-20

Table 4-2 Types of logs......................................................................................................................................4-22

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About This Document

Purpose

This document describes the structures, working principles, signal flows, and transmission and

networking of the BSC6900. It helps the reader understand the implementation and working

principles of the BSC6900.

Product Version

The following table lists the product version related to the document.

Product Name Product Version

BSC6900 V900R011C00

Intended Audience

This document is intended for:

l Network planners

l System engineers

l Field engineers

Organization

1 Changes in BSC6900 GSM Technical Description

This chapter describes the changes in the BSC6900 GSM Technical Description between

different versions.

2 Hardware Configuration Modes

The BSC6900 supports flexible hardware configuration modes. The hardware configuration

mode varies according to the scenario.

3 Overall Structure

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This chapter describes the interactions between the modules in the BSC6900.

4 Working Principles

This chapter describes the working principles of the BSC6900 in the following aspects: power

supply, environment monitoring, clock synchronization, and OM.

5 Signal Flow

The BSC6900 signal flow consists of the user-plane signal flow, control-plane signal flow, and

OM signal flow.

6 Transmission and Networking

The transmission and networking between the BSC6900 and other NEs can be classified into

the following types: transmission and networking on the A/Gb interface and on the Abis

interface.

ConventionsSymbol Conventions

The symbols that may be found in this document are defined as follows.

Symbol Description

Indicates a hazard with a high level of risk, which if not

avoided,will result in death or serious injury.

Indicates a hazard with a medium or low level of risk, which

if not avoided, could result in minor or moderate injury.

Indicates a potentially hazardous situation, which if not

avoided,could result in equipment damage, data loss,

performance degradation, or unexpected results.

Indicates a tip that may help you solve a problem or save

time.

Provides additional information to emphasize or supplement

important points of the main text.

General Conventions

The general conventions that may be found in this document are defined as follows.

Convention Description

Times New Roman Normal paragraphs are in Times New Roman.

Boldface Names of files, directories, folders, and users are in

boldface. For example, log in as userroot.

Italic Book titles are in italics.

Organization

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Courier New Examples of information displayed on the screen are in

Courier New.

Command Conventions

The command conventions that may be found in this document are defined as follows.


Boldface The keywords of a command line are in boldface.

Italic Command arguments are in italics.

[ ] Items (keywords or arguments) in brackets [ ] are optional.

{ x | y | ... } Optional items are grouped in braces and separated by

vertical bars. One item is selected.

[ x | y | ... ] Optional items are grouped in brackets and separated by

vertical bars. One item is selected or no item is selected.

{ x | y | ... }* Optional items are grouped in braces and separated by

vertical bars. A minimum of one item or a maximum of all

items can be selected.

[ x | y | ... ]* Optional items are grouped in brackets and separated by

vertical bars. Several items or no item can be selected.

GUI Conventions

The GUI conventions that may be found in this document are defined as follows.


Boldface Buttons, menus, parameters, tabs, window, and dialog titles

are in boldface. For example, clickOK.

> Multi-level menus are in boldface and separated by the ">"

signs. For example, choose File > Create > Folder.

Keyboard Operations

The keyboard operations that may be found in this document are defined as follows.

Format Description

Key Press the key. For example, press Enter and press Tab.

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Format Description

Key 1+Key 2 Press the keys concurrently. For example, pressing Ctrl+Alt

+A means the three keys should be pressed concurrently.

Key 1, Key 2 Press the keys in turn. For example, pressing Alt, A meansthe two keys should be pressed in turn.

Mouse Operations

The mouse operations that may be found in this document are defined as follows.

Action Description

Click Select and release the primary mouse button without moving

the pointer.

Double-click Press the primary mouse button twice continuously and

quickly without moving the pointer.

Drag Press and hold the primary mouse button and move the

pointer to a certain position.

Organization

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1 Changes in BSC6900 GSM TechnicalDescription

This chapter describes the changes in the BSC6900 GSM Technical Description between

different versions.

03 (2009-12-05)

This is the third commercial release.

Compared with issue 02 (2009-10-30) of V900R011C00, this issue does not incorporate added

or deleted sections.

Compared with issue 02 (2009-10-30) of V900R011C00, this issue incorporates the changes

described in the following table.

Topic Change

4.3.2 Structure of the Clock

Synchronization Subsystem

The description of the BSC6900 clock

synchronization subsystem structure is

modified.

Active/Standby Workspaces of the OMU The description ofRelation Between the

Active/Standby Workspaces of Host

Boards and the Active/Standby

Workspaces of the OMU is deleted, because

it is described in Active/StandbyWorkspaces of Host Boards.

5.1.2 GSM CS Signal Flow The description of the signal flow in Ater over

IP mode is added.

02 (2009-10-30)

This is the second commercial release.

Compared with issue 01 (2009-07-30) of V900R011C00, this issue does not incorporate addedor deleted sections.

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Compared with issue 01 (2009-07-30) of V900R011C00, this issue incorporates the changes

described in the following table.

Topic Change

3 Overall Structure The description of the BSC6900 softwarestructure is added.

01 (2009-07-30)

This is the first commercial release.

1 Changes in BSC6900 GSM Technical Description

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2Hardware Configuration ModesThe BSC6900 supports flexible hardware configuration modes. The hardware configuration

mode varies according to the scenario.

Learn the following concepts for a better understanding of the BSC6900.

BM/TC

The main processing subrack (MPS) and extended processing subrack (EPS) are collectively

known as basic module (BM) subrack. The transcoder subrack (TCS) is known as TC subrack.

Main TCS

The TCS that forwards the OM signals to other TCSs is called the main TCS. All other TCSsare called extension TCSs.

The main TCS is determined by both the cable connections and the data configuration. For details

of the cable connections, see switching subsystem.

Subrack Configuration Modes

The BSC6900 subracks can be configured in three modes:

l BM/TC separated

In BM/TC separated mode, the BSC6900 is configured with the MPS, EPS, and TCS (local

or remote).Characteristics: In this mode, the installation location of the TCS is flexible. The TCS can

be installed in the transcoder rack (TCR) and be placed on the CN side, thus saving the

transmission resources between the BSC6900 and the CN. Alternatively, the TCS can be

installed in the same cabinet as the MPS or EPS and be placed on the BSC6900 side.

l BM/TC combined

In BM/TC combined mode, the boards of the TCS are installed in the MPS or in the EPS,

with the subrack names unchanged.

Characteristics: The BSC6900 in this mode has higher hardware integration than in BM/

TC separated mode, When the capacity is the same, the BSC6900 in this mode has fewer

cabinets and subracks.

l A over IP

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In A over IP mode, layer 3 (network layer) of the protocol stack on the A interface adopts

the IP protocol. In this case, the BSC6900 is configured with the MPS and EPS but not

with the TCS. The TC function is performed by the Media Gateway (MGW).

Characteristics: In this mode, the BSC6900 has fewer cabinets and subracks. The

BSC6900 must be interconnected with a specific MGW.

The three subrack configuration modes are mutually exclusive. That is, one BSC6900 uses only

one configuration mode.

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3 Overall StructureAbout This Chapter

This chapter describes the interactions between the modules in the BSC6900.

Physical Structure

The BSC6900 cabinet consists of power distribution boxes and subracks, as listed in Table

3-1.

Table 3-1 Components of the BSC6900 cabinet

Component Description

MPS One MPS must be configured.

EPS Zero to five EPSs can be configured.

TCS Zero to four TCSs can be configured.

Independent fan subrack Each cabinet must be configured with one independent fan

subrack.

Power distribution box Each cabinet must be configured with one power distribution

box.

Software Structure

The software of the BSC6900 has a distributed architecture. It is classified into the host software

and OMU software.

l Host software

The host software is distributed on the service boards. It consists of the operating system,

middleware, and application software. See Figure 3-1.

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Figure 3-1 Structure of the host software

Operating system

The VxWorks real-time embedded operating system runs on each service board.

Middleware

The Versatile Protocol Platform (VPP) and the Virtual Operating System (VOS)function as the middleware. The middleware enables the upper-layer application

software to be independent from the lower-layer operating system so that software

functions can be transplanted between different platforms.

Application software

Boards of different types can be installed with different application software. The

application software is classified into radio resource processing software, resource

control-plane processing software, base station management software, and

configuration maintenance management software.

l OMU software

The Operation and Maintenance Unit (OMU) software runs on the OMUa board and it isresponsible for the operation and maintenance of the BSC6900. The OMU software consists

of the operating system and the OMU application software. See Figure 3-2.

Figure 3-2 Structure of the OMU software

Operating system

The OMUa board uses the Dopra Linux operating system.

OMU application software

The OMU application software runs on the lower-level operating system and provides

various service processes, including the LMT process, fault diagnosis process, and

authentication process.

Logical Structure

Figure 3-3 and Figure 3-4 show the logical structure of the BSC6900.

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Figure 3-3 Logical structure of MPS/EPS

Figure 3-4 Logical structure of TCS

The TCS that forwards the OM signals to other TCSs is called the main TCS.

The channel for the TCS and the MPS to exchange information varies according to the location

of the TCS: local or remote.

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l In local TCS mode, the SCUa board in the main TCS is connected to the SCUa board in

the MPS through the crossover cable.

l In remote TCS mode, the TCS is located in the TCR, which is separate from the cabinet

that houses the MPS/EPS. The main TCS and the MPS are connected through the cable

between the Ater interface boards.

Subsystems

Logically, the BSC6900 consists of the following five subsystems:

3.1 Switching Subsystem

The switching subsystem performs switching of traffic data, signaling, and OM signals.

3.2 Service Processing Subsystem

The BSC6900 service processing subsystem performs the control functions defined in the 3GPP

protocols and processes services of the BSC6900.

3.3 Interface Processing SubsystemThe interface processing subsystem provides transmission ports and resources, processes

transport network messages, and enables interaction between the BSC6900 internal data and

external data.

3.4 Clock Synchronization Subsystem

The clock synchronization subsystem provides clock signals for the BSC6900 and provides

reference clock signals for base stations.

3.5 OM Subsystem

The OM subsystem enables the management and maintenance of the BSC6900 in the following

scenarios: routine maintenance, emergency maintenance, upgrade, and capacity expansion.

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3.1 Switching Subsystem

The switching subsystem performs switching of traffic data, signaling, and OM signals.

Position of the Switching Subsystem in the BSC6900 System

The switching subsystem consists of logical modules of two types: MAC switching and TDM

switching. Figure 3-5 and Figure 3-6 show the position of the switching subsystem in the MPS/

EPS and TCS respectively, with the modules highlighted in apricot.

Figure 3-5 Position of the switching subsystem in the MPS/EPS

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Figure 3-6 Position of the switching subsystem in the TCS

Functions

l Provides intra-subrack Medium Access Control (MAC) switching

l Provides intra-subrack Time Division Multiplexing (TDM) switching

l Provides inter-subrack MAC switching and TDM switching

l Distributes clock signals to the service processing boards

Hardware Involved

The switching subsystem consists of the SCUa boards, TNUa boards, high-speed backplane

channels in each subrack, crossover cables between SCUa boards, and inter-TNUa cables.

Network Topologies Between Subracks

The BSC6900 subracks can be connected in the star or mesh topology. In Figure 3-7, (1) and

(2) represent the star and mesh topologies respectively, where the dots represent subracks.

l Star topology

One node functions as the center node and it is connected to each of the other nodes. The

communication between the other nodes must be switched by the center node.

l Mesh topology

There is a connection between every two nodes. When any node is out of service, the

communication between other nodes is not affected.

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Figure 3-7 Network topologies between subracks

In the switching subsystem of the BSC6900, the star topology is established among the MAC

switching logical modules, and the mesh topology is established among the TDM switching

logical modules.

Inter-Subrack Connection

The MAC switching logical modules switch the IP-based traffic data, OM signals, and signaling.

The switching is performed by the SCUa boards and the Ethernet cables between the SCUa

boards. The inter-subrack connections related to MAC switching can be classified into the

following types:

l Interconnections between the MPS and the EPSs

The MPS functions as the main subrack, and a maximum of three EPSs function as

extension subracks. The star interconnections between the MPS and the EPSs are

established through the Ethernet cables between the SCUa boards, as shown in Figure

3-8.l Interconnections between the TCSs

One TCS functions as the main subrack, and a maximum of three TCSs function as

extension subracks. The star interconnections between the TCSs are established through

the Ethernet cables between the SCUa boards, as shown in Figure 3-9.

Figure 3-8 Interconnections between subracks through the crossover cables between the SCUa

boards (MPS/EPS)

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Figure 3-9 Interconnections between subracks through the crossover cables between the SCUa

boards (TCS)

The TDM switching logical modules switch the TDM-based traffic data. The switching is

performed by the TNUa boards and the inter-TNUa cables. The inter-subrack connections related

to TDM switching can be classified into the following types:

l Interconnections between the MPS and the EPSs

The mesh interconnections between the MPS and the EPSs are established through the

inter-TNUa cables, as shown in Figure 3-10.

l Interconnections between the TCSs

The mesh interconnections between the TCSs are established through the inter-TNUa

cables, as shown in Figure 3-11.

Figure 3-10 Interconnections between subracks through the inter-TNUa cables (MPS/EPS)

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Figure 3-11 Interconnections between subracks through the inter-TNUa cables (TCS)

3.2 Service Processing Subsystem

The BSC6900 service processing subsystem performs the control functions defined in the 3GPP

protocols and processes services of the BSC6900.

Position of the Service Processing Subsystem in the BSC6900 System

The service processing subsystem mainly consists of two logical modules: BSC control plane

(CP) and BSC user plane (UP). Figure 3-12 shows the position of the service processing

subsystem in the BSC6900 system, with the modules highlighted in apricot.

NOTE

For details about the definitions of CP and UP, see 5 Signal Flow.

Figure 3-12 Service processing subsystem

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Functions

The service processing subsystem performs the following functions:

l User data transfer

l System admission control

l Radio channel ciphering and deciphering

l Data integrity protection

l Mobility management

l Radio resource management and control

l Cell broadcast service control

l System information and user message tracing

l Data volume reporting

l Radio access management

l CS service processing

l PS service processing

Service processing subsystems can be increased as required, according to the linear superposition

principle. Thus, the service processing capability of the BSC6900 is improved.

Service processing subsystems communicate with each other through the switching subsystem

to form a resource pool and perform tasks cooperatively.

Hardware Involved

The service processing subsystem consists of the XPUa, XPUb, DPUc, and DPUd boards. The

XPUa and XPUb boards process signaling. The DPUc and DPUd boards process services.

3.3 Interface Processing Subsystem

The interface processing subsystem provides transmission ports and resources, processes

transport network messages, and enables interaction between the BSC6900 internal data and

external data.

Position of the Interface Processing Subsystem in the BSC6900 System

The interface processing subsystem consists of two types of interfaces: IP interfaces and TDM

interfaces. Figure 3-13 and Figure 3-14 show the position of the interface processing subsystem

in the BSC6900 system, with the interfaces highlighted in apricot.

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Figure 3-13 Position of the interface processing subsystem in the MPS/EPS

Figure 3-14 Position of the interface processing subsystem in the TCS

Functions

l The interface processing subsystem provides the following types of IP and TDM interfaces.

E1/T1 electrical ports

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STM-1 optical ports

FE/GE electrical ports

GE optical ports

l The interface processing subsystem processes transport network messages. It also hides the

differences between transport network messages within the BSC6900.

l On the uplink, the interface processing subsystem terminates transport network messages

at the interface boards. It also transmits the user plane, control plane, and management

plane datagrams to the corresponding service processing boards. The processing of the

signal flow on the downlink is the reverse of the processing of the signal flow on the uplink.

Hardware Involved

The interface processing subsystem consists of the Abis, A, Ater, Gb, and Pb interface boards.

3.4 Clock Synchronization SubsystemThe clock synchronization subsystem provides clock signals for the BSC6900 and provides

reference clock signals for base stations.

Position of the Clock Synchronization Subsystem in the BSC6900 System

Figure 3-15 shows the position of the clock synchronization subsystem in the BSC6900 system,

with the clock module highlighted in apricot.

Figure 3-15 Position of the clock synchronization subsystem in the BSC6900 system

Functions

The clock synchronization subsystem provides the following clock sources for the BSC6900and ensures the reliability of the clock signals:

3 Overall Structure

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l Building Integrated Timing Supply System (BITS) clock

l External 8 kHz clock

l LINE clock

The BSC6900 provides reference clock sources for base stations. Clock signals are transmittedfrom the BSC6900 to base stations over the Abis interface.

Hardware Involved

The clock synchronization subsystem consists of the GCUa board.

3.5 OM Subsystem

The OM subsystem enables the management and maintenance of the BSC6900 in the following

scenarios: routine maintenance, emergency maintenance, upgrade, and capacity expansion.

Position of the OM Subsystem in the BSC6900 System

Figure 3-16 shows the position of the OM subsystem in the BSC6900 system, with the OM

module highlighted in apricot.

Figure 3-16 Position of the OM subsystem in the BSC6900 system

Functions

The OM subsystem provides the following types of management for the BSC6900:

l 4.4.4 Data Configuration Management

l 4.4.5 Security Management

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l 4.4.6 Performance Management

l 4.4.7 Alarm Management

l 4.4.8 Loading Management

l

4.4.9 Upgrade Managementl 4.4.10 BTS Loading Management

l 4.4.11 BTS Upgrade Management

Hardware Involved

The OM subsystem consists of the OMUa board.

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4Working PrinciplesAbout This Chapter

This chapter describes the working principles of the BSC6900 in the following aspects: power

supply, environment monitoring, clock synchronization, and OM.

4.1 Power Supply Principle

The power supply subsystem of the BSC6900 adopts the dual-circuit design and point-by-point

monitoring solution. It consists of the power input part and the power distribution part.

4.2 Environment Monitoring Principle

The environment monitoring subsystem of the BSC6900 comprises the power distribution box

and the environment monitoring parts in each subrack. The environment monitoring subsystem

monitors and controls the power supply, fans, and operating environment.

4.3 Clock Synchronization Principle

The clock synchronization subsystem of the BSC6900 consists of the GCUa board and the clock

processing units of each subrack. It provides clock signals for the BSC6900 and reference clocks

for base stations.

4.4 OM Principle

OM is performed in the following scenarios: routine maintenance, emergency maintenance,

troubleshooting, device upgrade, and capacity expansion. In addition, OM can be performed to

rapidly adjust device status.

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4.1 Power Supply Principle

The power supply subsystem of the BSC6900 adopts the dual-circuit design and point-by-pointmonitoring solution. It consists of the power input part and the power distribution part.

The power supply subsystem of the BSC6900 consists of the -48 V DC power system, DC power

distribution frame (PDF), and DC power distribution box (PDB) at the top of the cabinet.

If a site has heavy traffic or more than two switching systems, two or more independent power

supply systems should be provided. In the case of a communication center, independent power

supply systems should be configured on different floors to provide supply power to different

equipment rooms.

Power Input Part

The power input part leads the power from the DC PDF to the power distribution box in the

cabinet. The power input part consists of the DC PDF, power distribution box, and cables

between them.

Figure 4-1 shows the power input part of the BSC6900.

Figure 4-1 Power input part of the BSC6900

NOTE

The DC PDF and the DC power distribution panel are not regarded as the components of the BSC6900.

The working principle of the power input part is as follows:

l The DC PDF provides each cabinet with dual two-route -48 V DC inputs and one route for

PGND connection.

l Typically, the two power inputs work concurrently. If one power input is faulty, the other

power input continues to supply power to the system to ensure stable operation. You can

rectify the faulty power input without interrupting the services, thereby ensuring the

optimum reliability and availability of the power supply subsystem.


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Power Distribution Part

The power distribution part distributes power from the power distribution box to various

components in the cabinet. It comprises the power distribution box, power distribution switches,

and various components in the cabinet.

The working principle of the power distribution part is as follows:

l The PDB performs lightning protection and overcurrent protection on the dual two-route

-48 V DC inputs. It then supplies power to all the components in the cabinet.

l The power distribution box monitors each input in real time. After the power distribution

box detects abnormal power supply, it reports the relevant alarms to the OMUa board. The

OMUa board, then, forwards the alarms to the LMT or M2000.

l The power distribution varies according to the type of cabinet. For details, see Connections

of Power Cables and PGND Cables in the Cabinet.

4.2 Environment Monitoring PrincipleThe environment monitoring subsystem of the BSC6900 comprises the power distribution box

and the environment monitoring parts in each subrack. The environment monitoring subsystem

monitors and controls the power supply, fans, and operating environment.

Power Monitoring

The power monitoring involves monitoring the power subsystem in real time, reporting the

operating status of the power supply, and generating alarms when faults occur.

Figure 4-2 shows the working principle of power monitoring.

Figure 4-2 Working principle of power monitoring

The power monitoring process is as follows:

1. The PAMU in the power distribution box monitors the operating status of the power

distribution box and sends the monitoring signals to the signal transfer board through theserial port.

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2. The signal transfer board transmits the power monitoring signals to the independent fan

subrack at the bottom of the cabinet through the monitoring signal cable of the power

distribution box. Then, the fan subrack forwards the power monitoring signals to the active

SCUa board in the power monitoring subrack.

3. The SCUa board processes the monitoring signals. If faults occur, the SCUa board generatesalarms and reports the alarms to the OMUa board. The OMUa board then forwards the

alarms to the LMT or M2000.

Fan Monitoring

The fan monitoring involves monitoring the operating status of the fans in real time and adjusting

the speed of the fans based on the temperature in the subrack.

Each subrack is configured with a built-in fan box. The temperature sensor next to the air outlet

can detect the temperature in the subrack.

Besides the built-in fan box in the subrack, there is an independent fan subrack at the bottom ofthe cabinet. This improves the reliability of heat dissipation of the cabinet.

Figure 4-3 shows the working principle of fan monitoring.

Figure 4-3 Working principle of fan monitoring

The fan monitoring process is as follows:

1. The built-in fan box in the subrack and the fan monitoring unit PFCU in the independent

fan subrack monitor the operating status of the fans in real time and reports the monitoring

signals to the signal transfer board through the serial port.

2. The signal transfer board transmits the monitoring signals to the active SCUa board.

l In the case of built-in fan box in the subrack, the signal transfer board transmits the

monitoring signals to the active SCUa board through the backplane of the subrack.

l In the case of independent fan subrack, the signal transfer board transmits the monitoring

signals to the active SCUa board in the fan monitoring subrack through the monitoringsignal cable.


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3. The SCUa board processes the monitoring signals. If faults occur, the SCUa board generates

alarms and reports the alarms to the OMUa board. The OMUa board then forwards the

alarms to the LMT or M2000.

Environment MonitoringThe environment monitoring involves monitoring the temperature, humidity, operating voltage,

door status, water damage, smoke, and infrared. The environment monitoring function is

performed by the Environment Monitor Units (EMUs).

Figure 4-4 shows the working principle of environment monitoring.

Figure 4-4 Working principle of environment monitoring

If the power distribution box can transfer signals, the environment monitoring process is as

follows:

1. The sensors monitor the environment in real time and send the monitoring signals to the

EMU.

2. The EMU sends the monitoring signals to the power distribution box through the serialcable.

3. The signal transfer board in the power distribution box transmits the monitoring signals to

the active SCUa board in the power monitoring subrack through the monitoring signal cable

of the power distribution box.

4. The active SCUa board in the power monitoring subrack transmits the monitoring signals

to the SCUa board in the MPS through the crossover cables between the SCUa boards.

5. The SCUa board in the MPS processes the monitoring signals. If faults occur, the SCUa

board generates alarms and reports the alarms to the OMUa board. The OMUa board then

forwards the alarms to the LMT or M2000.

If the power distribution box cannot transfer signals, the environment monitoring process is asfollows:

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1. The sensors monitor the environment in real time and send the monitoring signals to the

EMU.

2. The EMU sends the monitoring signals to the active SCUa board in the lowest subrack

through the serial cable.

3. The active SCUa board in the lowest subrack transmits the monitoring signals to the SCUaboard in the MPS through the crossover cables between the SCUa boards.

4. The SCUa board in the MPS processes the monitoring signals. If faults occur, the SCUa

board generates alarms and reports the alarms to the OMUa board. The OMUa board then

forwards the alarms to the LMT or M2000.

4.3 Clock Synchronization Principle

The clock synchronization subsystem of the BSC6900 consists of the GCUa board and the clock

processing units of each subrack. It provides clock signals for the BSC6900 and reference clocks

for base stations.

4.3.1 Clock Sources

The BSC6900 can use the following clock sources: Building Integrated Timing Supply System

(BITS) clock, external 8 kHz clock, and LINE clock.

4.3.2 Structure of the Clock Synchronization Subsystem

The clock synchronization subsystem consists of the clock board, backplanes, clock cables

between subracks, and clock module in each board.

4.3.3 Clock Synchronization Process

The BSC6900 processes external clock signals before sending them to its boards. The clock

synchronization process varies slightly from one subrack to another.

4.3.1 Clock Sources

The BSC6900 can use the following clock sources: Building Integrated Timing Supply System

(BITS) clock, external 8 kHz clock, and LINE clock.

External Clocks

The external clocks of the BSC6900 are of two types:

l BITS Clock

The BITS clock signals are of three types: 2 MHz, 2 Mbit/s, and 1.5 Mbit/s. The 2 MHz

and 2 Mbit/s clock signals are E1 clock signals, and the 1.5 Mbit/s clock signals are T1

clock signals.

The BITS clock has two input modes: BITS0 and BITS1. BITS0 and BITS1 correspond

to the CLKIN0 and CLKIN1 ports on the GCUa board respectively. The BSC6900

obtains the BITS clock signals through the CLKIN0 or CLKIN1 port on the GCUa/

GCGa board.

l External 8 kHz Clock

Through the COM1 port on the GCUa board, the BSC6900 obtains 8 kHz standard clock

signals from an external device.


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LINE Clock

The LINE clock is an 8 kHz clock that is transmitted from an interface board in the MPS to the

GCUa board through the backplane channel. The LINE clock has two input modes: LINE0 and

LINE1.

NOTE

LINE0 and LINE1 correspond to backplane channel 1 and backplane channel 2 respectively.

4.3.2 Structure of the Clock Synchronization Subsystem

The clock synchronization subsystem consists of the clock board, backplanes, clock cables

between subracks, and clock module in each board.

Figure 4-5 shows the structure of the clock synchronization subsystem.

Figure 4-5 Structure of the clock synchronization subsystem

The structure of the BSC6900 clock synchronization subsystem is described as follows:

l The clock board of the BSC6900 is the GCUa board.

l If the MPS extracts the clock signals, the clock signals enter the MPS through the port on

the panel of the GCUa board.

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NOTE

The EPS of BSC6900 cannot obtain the clock source.

l If the interface board that extracts the line clock signals from the CN is located in a TCS,

the clock signals travel to the Ater interface board in the TCS through the backplane. Then,

the Ater interface board in the TCS transmits the clock signals to the Ater interface board

in the MPS through straight-through cables between subracks. In the MPS, the Ater

interface board transmits the clock signals to the clock board through the backplane.

l If the BSC6900 is configured with the Gb interface board, the Gb interface board extracts

clock signals either from the backplane or from the CN. The Gb interface board, however,

cannot extract clock signals from them simultaneously. If the PS services and CS services

use different clock sources and the clock signals are extracted from the CN, the Gb interface

board serves only the Gb interface.

Figure 4-6 shows the connections of the clock cables between the clock boards in the MPS and

the SCUa boards in the EPS when the BSC6900 is configured with active and standby clock

boards and SCUa boards.

Figure 4-6 Structure of the clock synchronization subsystem

The active and standby clock boards in the MPS are connected to the active and standby SCUa

boards in the EPS through the Y-shaped clock signal cables. This connection mode ensures that

the system clock of the BSC6900 works properly in the case of a single-point failure of the clock

board, Y-shaped clock signal cable, or SCUa board. In addition, the Y-shaped clock signal cable

ensures the proper working of the SCUa boards during the switchover of the active and standby

clock boards.

NOTE

In the MPS, the clock board sends clock signals to the SCUa board in the same subrack through the backplane

channel. Therefore, a Y-shaped clock signal cable is not required.


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4.3.3 Clock Synchronization Process

The BSC6900 processes external clock signals before sending them to its boards. The clock

synchronization process varies slightly from one subrack to another.

Process of Clock Synchronization in the MPS/EPS

The clock signals of the MPS/EPS are generated by the clock board. The clock board can extract

clock signals from an external device or extract LINE clock signals from the A interface.

l Figure 4-7 shows the process of clock synchronization in the MPS/EPS when the clock

board extracts clock signals from an external device.

l Figure 4-8 shows the process of clock synchronization in the MPS/EPS when the clock

board extracts LINE clock signals from the A interface.

Figure 4-7 Process of clock synchronization in the MPS/EPS (1)

Figure 4-8 Process of clock synchronization in the MPS/EPS (2)

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As shown in Figure 4-7 and Figure 4-8, 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 LINE clock is used, clocks 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 SCUa board in the MPS through the backplane and to the SCUa

board in each EPS through the clock signal output ports.

3. The SCUa board in the MPS/EPS transmits the clock signals to the other boards in the same

subrack through the backplane.

NOTE

The Abis interface boards transmit the clock signals to base stations.

Process of Clock Synchronization in the TCS

Figure 4-9 shows the process of clock synchronization in the TCS when the TCS extracts LINE

clock signals from the A interface.

Figure 4-9 Process of clock synchronization in the TCS

1. The TCS extracts LINE clock signals from the A interface. Then, the LINE clock signals

are processed by the A interface board to obtain the required clock signals.

2. In the TCS, the A interface board transmits the clock signals to the SCUa board through

the backplane. Then, the SCUa board transmits the clock signals to the other boards in the

TCS.

NOTE

l In A over IP over Ethernet mode, the BSC6900 can extract only external clock signals.

l In A over IP over E1/T1 mode, the BSC6900 can extract only LINE clock signals.

4.4 OM Principle

OM is performed in the following scenarios: routine maintenance, emergency maintenance,

troubleshooting, device upgrade, and capacity expansion. In addition, OM can be performed to

rapidly adjust device status.


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4.4.1 Dual OM Plane

The BSC6900 has a dual OM plane to prevent single-point failure from affecting the normal

operation and maintenance.

4.4.2 OM Network

The OM network of the BSC6900 consists of the M2000, LMT, OMUa boards, SCUa boards,and OM modules in other boards.

4.4.3 Active/Standby Workspaces

This section describes the active/standby workspaces of the OMU and those of the host boards.

4.4.4 Data Configuration Management

The data configuration management involves managing the data configuration process of the

BSC6900 so that configuration data is properly sent to the related boards in a secure manner.

4.4.5 Security Management

The security management ensures the security of user login and helps to identify equipment

faults. It involves rights management, log management, and inventory management.

4.4.6 Performance Management

The BSC6900 performance management involves collecting, analyzing, and querying

performance data.

4.4.7 Alarm Management

The alarm management helps you monitor the running status of the BSC6900 and informs you

of faults in real time so that you can take measures in time.

4.4.8 Loading Management

The BSC6900 loading management involves managing the process of loading program and data

files onto boards after the boards (or subracks) are started or restarted.

4.4.9 Upgrade ManagementThe upgrade management involves managing the procedures for upgrading the OMU software

and patch.

4.4.10 BTS Loading Management

The BTS loading management involves managing the process of loading software to the boards

in the BTS.

4.4.11 BTS Upgrade Management

The BTS upgrade management refers to upgrading the BTS to a later version. You can locally

or remotely upgrade multiple BTSs through the OM network.

4.4.1 Dual OM PlaneThe BSC6900 has a dual OM plane to prevent single-point failure from affecting the normal

operation and maintenance.

The BSC6900 OM subsystem adopts the dual-plane design, as shown in Figure 4-10.

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Figure 4-10 Dual OM plane

NOTE

If the internal network and external networkare on different network segments, ensure that the two networksare isolated.

The dual OM 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 OM

channel works properly.

The active/standby OMUa boards use the same external virtual IP address to communicate with

the LMT or M2000 and use the same internal virtual IP address to communicate with the SCUa

board.

l When the active OMUa board is faulty, an active/standby switchover is performed

automatically, and the standby OMUa board takes over the OM task. In this case, theinternal and external virtual IP addresses remain unchanged. Thus, the proper

communication between the internal and external networks of the BSC6900 is ensured.

l When a single-point failure occurs on the switching network, the active/standby SCUa

boards in each subrack are switched over automatically to ensure that the OM channel

works properly.

4.4.2 OM Network

The OM network of the BSC6900 consists of the M2000, LMT, OMUa boards, SCUa boards,

and OM modules in other boards.

Figure 4-11 shows the structure of the BSC6900 OM network.


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Figure 4-11 Structure of the OM network

NOTE

Figure 4-11 shows some of the boards in the OM network.

The SCUa boards in the EPS/TCS are connected to the SCUa boards in the MPS through crossover cables. The

crossover cables transmit OM signals from the MPS to the EPS/TCS.

In remote TCS mode, the SCUa boards in the TCS are connected to the SCUa boards in the MPS through the

cables between the Ater interface boards. These cables transmit OM signals from the MPS to the TCS.

M2000

The M2000 is a centralized network management system. The M2000 is connected to the

BSC6900 through Ethernet cables. One M2000 can remotely manage multiple BSC6900s.

LMT

The LMT is connected to the OMUa board of the BSC6900 and works on the Windows XP

Professional or Windows Vista operating system. One or more LMTs can be connected to theOMUa board directly or through networks. The maintenance of the BSC6900 can be performed

locally or remotely through the LMT. The LMT is connected to an alarm box through a serial

cable.

OMUa Board

The OMUa board is the back administration module of the BSC6900. It is connected to an

external device through the Ethernet cable. The BSC6900 can be configured with one OMUa

board in independent mode or with two OMUa boards in active/standby mode.

The OMUa board functions as a bridge between the BSC6900 and the LMT/M2000. The OMnetwork of the BSC6900 is classified into the following networks:

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l Internal network: implements the communication between the OMUa board and the host

boards of the BSC6900.

l External network: implements the communication between the OMUa board and external

devices, such as the LMT or M2000.

SCUa Board

The SCUa board is the switching and control board of the BSC6900. It is responsible for the

OM of the subrack where it is located. If a subrack is configured with two SCUa boards, then

the two boards work in active/standby mode.

The SCUa board performs OM on other boards in the same subrack through the backplane

channels. The SCUa boards in different subracks are connected through crossover cables.

4.4.3 Active/Standby Workspaces

This section describes the active/standby workspaces of the OMU and those of the host boards.

Active/Standby Workspaces of the OMU

The active/standby workspaces of the OMU are used for the upgrade and rollback of the

BSC6900 versions, thus enabling quick switching between versions.

Concept of the Active/Standby Workspaces of the OMU

The active/standby workspaces of the OMU refer to the active/standby workspaces for storing

the version files on the OMU. Each workspace is used to store files of different versions.

The relation between the active/standby workspaces is relative. The active/standby relation

depends on the storage location of the running version. The workspace that stores the running

OMU version files is the active workspace, and the other is the standby workspace.

Working Principles of the Active/Standby Workspaces of the OMU

The working principles of the OMU active/standby workspaces in the case of the OMU version

upgrade are as follows:

1. The standby workspace of the active OMU is upgraded to a new version.

2. The standby workspace of the standby OMU is upgraded to a new version.

3. A switchover is performed between the active and standby workspaces of the active OMU.The standby workspace that stores the new version of files becomes active, and the other

workspace becomes standby.

4. The active OMU runs the upgraded version.

5. A switchover is performed between the active and standby workspaces of the standby OMU

to ensure that the versions of the workspaces are consistent with those of the active OMU.

6. The OMU version upgrade is complete.

After the OMU version upgrade, the standby workspaces of the active and standby OMUs store

the files of the old version. In this case, version rollback can be performed as required.

The working principles of the OMU active/standby workspaces in the case of version rollbackare as follows:


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1. A switchover is performed between the active and standby workspaces of the active OMU.

The running version of the active OMU is rolled back to the pre-upgrade version.

2. The active OMU runs the pre-upgrade version.

3. A switchover is performed between the active and standby workspaces of the standby OMU

to ensure that the versions of the workspaces are consistent with those of the active OMU.

4. The OMU version rollback is complete.

Relation Between Intra-OMU Active and Standby Workspaces

The active and standby workspaces of the OMU are independent of each other. The operation

of the active workspace does not change any information in the standby workspace.

Relation Between Inter-OMU Active and Standby Workspaces

The active and standby workspaces of the active OMU correspond to the active and standbyworkspaces of the standby OMU respectively. Between the active and standby OMUs, the files

in the active workspaces are automatically synchronized in real time, but those in the standby

workspaces need to be synchronized manually.

Active/Standby Workspaces of Host Boards

BSC6900 host boards refer to all the boards except the OMUa board. The active/standby

workspaces of host boards are used for file loading, version upgrade, and version rollback.

Concept of the Active/Standby Workspaces of Host Boards

The active/standby workspaces of host boards refer to the active/standby workspaces for storing

different versions of programs, data, and patch files in the board flash memory.

The relation between the active/standby workspaces is a relative concept. The active/standby

relation depends on the running version. The workspace that stores the running version files of

a board is the active workspace, and the other is the standby workspace.

Working Principles of the Active/Standby Workspaces of Host Boards

Before loading programs and data files, host boards choose the loading mode according to the

loading control parameter. For details, see 4.4.8 Loading Management.

Relation Between Intra-Board Active/Standby Workspaces

The active and standby workspaces of a host board are independent of each other. The operation

of the active workspace does not change any information in the standby workspace.

Relation Between Inter-Board Active/Standby Workspaces

The active and standby workspaces of the active board are independent of the active and standby

workspaces of another host board. The operation of the active board does not change any

information in the standby board.

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Relation Between the Active/Standby Workspaces of Host Boards and the Active/Standby Workspaces of the OMU

On the active workspaces of the host boards, files can be loaded only from the active workspace

of the OMU. On the standby workspaces of the host boards, files can be loaded only from thestandby workspace of the OMU.

4.4.4 Data Configuration Management

The data configuration management involves managing the data configuration process of the

BSC6900 so that configuration data is properly sent to the related boards in a secure manner.

Data Configuration Modes

The BSC6900 supports two data configuration modes: effective mode and ineffective mode.

Effective Mode and ineffective Mode

l Effective mode

If data configuration is performed on the BSC6900 in effective mode, then the relevant

configuration data takes effect on the host boards in real time.

l Ineffective mode

If data configuration is performed on the BSC6900 in ineffective mode, then the relevant

configuration data takes effect only after the BSC6900 is reset.

Principle of Effective Mode ConfigurationEffective mode configuration is applied to dynamic modification of the BSC6900 configuration

data.

Figure 4-12 shows the principle of effective mode configuration.

Figure 4-12 Principle of effective mode configuration

The process of effective mode configuration is as follows:

1. The BSC6900 is switched to effective mode.

2. The configuration console (LMT or M2000) sends MML commands to the configurationmanagement module of the OMU.


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3. 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.

Principle of Ineffective Mode Configuration

Ineffective mode configuration is applied to BSC6900 initial configuration.

Figure 4-13 shows the principle of ineffective mode configuration.

Figure 4-13 Principle of ineffective mode configuration

The process of ineffective mode configuration is as follows:

1. The BSC6900 is switched to ineffective mode.

2. The configuration console (LMT or M2000) sends MML commands to the configuration

management module of the OMU.

3. The configuration management module sends only the configuration data to the OMU

database.

4. When a subrack or the BSC6900 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 Rollback

Data configuration rollback is performed to recover configurations when errors occur. If the

modified data configuration fails to reach the expected result or even causes equipment or

network failure, you can perform rollback to recover the configurations and to ensure the proper

operation of the BSC6900.

WARNING

Data configuration rollback cannot be performed when the CM control enable switch is set to

ON, when the fast configuration mode is selected, or when batch configuration is performed.

Data configuration rollback consists of the following types of operation:

l Undoing a single configuration command

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After you undo the latest ten commands one by one, the system rolls back to the

configuration before each command is executed.

l Redoing a single configuration command

After you redo the latest ten commands one by one, the system rolls back to the

configuration after each command is executed.

l Undoing configuration commands in batches

This operation is performed to undo all the configuration commands that were executed

after a specified rollback savepoint. After this operation, the system rolls back to the

configuration at the specified rollback savepoint.

l Redoing configuration commands in batches

This operation is performed to redo the configurations that were rolled back in batches.

After this operation, the system returns to the configuration at the specified rollback

savepoint or the configuration after the commands were executed.

Data Configuration Rights Management

The data configuration rights management controls the data configuration rights and the number

of users that simultaneously perform data configuration on the BSC6900 through the LMT or

M2000. This ensures the security of data configuration.

The principles of data configuration rights management are as follows:

l The data configuration rights management enables only one user to perform data

configuration on the BSC6900 through the LMT or M2000 at a time.

l The user must have data configuration rights.

With the data configuration rights management, users cannot configure data for the BSC6900at the same time.

Data Configuration Check

The data configuration check involves the data validity check and data consistency check. This

ensures the normal operation of the BSC6900.

Data Validity Check

The data validity check involves checking 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 isperformed. If there is an error in the configuration, the BSC6900 stops the configuration or the

running of the command. At the same time, a warning message is displayed.

Data Consistency Check

The data consistency check consists of two parts:

l Check of the data consistency between the active and standby OMUs

If the BSC6900 is configured with the active and standby OMUs, the data on the active

OMU must be the same as that on the standby OMU, thus ensuring the reliability of the

BSC6900. If the active OMU is faulty, the standby OMU takes over the task from the activeOMU after an active/standby switchover.


BSC6900 GSM




Iss

bsc6900 gsm technical description-(v900r011c00_03)

Documents