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Copyright Huawei Technologies Co., Ltd. 2010. All rights reserved.
No part of this document may be reproduced or transmitted in any form or by any means without prior written
consent of Huawei Technologies Co., Ltd.
Trademarks and Permissions
and other Huawei trademarks are trademarks 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, and
recommendations in this document do not constitute the warranty of any kind, express or implied.
Huawei Technologies Co., Ltd.
Address: Huawei Industrial Base
Bantian, Longgang
Shenzhen 518129
People's Republic of China
Website: http://www.huawei.com
Email: [email protected]
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About This Document
Purpose
This document describes the structure, 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 V900R012C01
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 between different versions of the BSC6900 GSM Technical
Description.
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 ways: 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, on the Abis interface,
on the Ater interface, and on the Pb interface.
7 Parts Reliability
The BSC6900 guarantees its operation reliability by means of board redundancy and port
redundancy.
Conventions
Symbol 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 notavoided,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.
About This Document
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Convention Description
Boldface Names of files, directories, folders, and users are in
boldface. For example, log in as user root.
Italic Book titles are in italics.
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.
Convention Description
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 byvertical 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.
Convention Description
Boldface Buttons, menus, parameters, tabs, window, and dialog titles
are in boldface. For example, click OK.
> Multi-level menus are in boldfaceand 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.
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Format Description
Key Press the key. For example, press Enterand press Tab.
Key 1+Key 2 Press the keys concurrently. For example, pressing Ctrl+Alt
+Ameans the three keys should be pressed concurrently.
Key 1, Key 2 Press the keys in turn. For example, pressing Alt, Ameans
the 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.
About This Document
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Contents
About This Document...................................................................................................................iii
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 SupplyPrinciple...................................................................................................................................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.................................................................................................................................................4-11
4.4.1 DualOM Plane.....................................................................................................................................4-12
4.4.2 OMNetwork............................................................................ ............................................................4-13
4.4.3 Active/Standby Workspaces................................................................................................................4-14
4.4.4 DataConfiguration Management.........................................................................................................4-16
4.4.5 Security Management...........................................................................................................................4-20
4.4.6 Performance Management....................................................................................................................4-23
4.4.7 Alarm Management..............................................................................................................................4-25
4.4.8 Loading Management...........................................................................................................................4-26
4.4.9 Upgrade Management..........................................................................................................................4-31
4.4.10 BTS Loading Management................................................................................................................4-33
4.4.11 BTS Upgrade Management................................................................................................................4-34
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
7 Parts Reliability..........................................................................................................................7-1
7.1 Concepts Related to Parts Reliability..............................................................................................................7-2
7.1.1 Backup....................................................................................................................................................7-2
7.1.2 Resource Pool.........................................................................................................................................7-3
7.1.3 Port Trunking.........................................................................................................................................7-3
7.1.4 Port Load Sharing...................................................................................................................................7-4
7.2 Board Redundancy..........................................................................................................................................7-4
7.2.1 Backup of EIUa Boards..........................................................................................................................7-5
7.2.2 Backup of OIUa Boards.........................................................................................................................7-5
7.2.3 Backup of PEUa Boards.........................................................................................................................7-6
7.2.4 Backup of POUc Boards........................................................................................................................7-7
7.2.5 Backup of SCUa Boards........................................................................................................................7-8
7.2.6 Backup of TNUa Boards........................................................................................................................7-87.2.7 Backup of FG2a/FG2c Boards...............................................................................................................7-9
7.2.8 Backup of GCUa/GCGa Boards..........................................................................................................7-10
7.2.9 Backup of GOUa/GOUc Boards..........................................................................................................7-11
7.2.10 Backupof OMUa/OMUb Boards......................................................................................................7-12
7.2.11 Backupof XPUa/XPUb Boards.........................................................................................................7-13
7.2.12 Resource Pool of DPUa/DPUc/DPUd Boards...................................................................................7-13
7.3 Port Redundancy...........................................................................................................................................7-14
7.3.1 Optical Port Backup.............................................................................................................................7-14
7.3.2 FE/GE Port Backup..............................................................................................................................7-15
7.3.3 Port Load Sharing.................................................................................................................................7-15
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7.3.4 Port Trunking.......................................................................................................................................7-16
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Figures
Figure 3-1Structure of the host software.............................................................................................................3-2
Figure 3-2Structure of the OMU software..........................................................................................................3-2
Figure 3-3Logical structure of MPS/EPS............................................................................................................3-3
Figure 3-4Logical structure of TCS.................................................................................................................... 3-3
Figure 3-5Position of the switching subsystem in the MPS/EPS........................................................................3-5
Figure 3-6Position of the switching subsystem in the TCS................................................................................ 3-6
Figure 3-7Network topologies between subracks...............................................................................................3-7
Figure 3-8Interconnections between subracks through the crossover cables between the SCUa boards (MPS/EPS)
...............................................................................................................................................................................3-7
Figure 3-9Interconnections between subracks through the crossover cables between the SCUa boards (TCS)
...............................................................................................................................................................................3-8
Figure 3-10Interconnections between subracks through the inter-TNUa cables (MPS/EPS).............................3-8
Figure 3-11Interconnections between subracks through the inter-TNUa cables (TCS)..................................... 3-9
Figure 3-12Service processing subsystem.......................................................................................................... 3-9
Figure 3-13Position of the interface processing subsystem in the MPS/EPS...................................................3-11
Figure 3-14Position of the interface processing subsystem in the TCS............................................................3-11
Figure 3-15Position of the clock synchronization subsystem in the BSC6900 system....................................3-12
Figure 3-16Position of the OM subsystem in the BSC6900 system.................................................................3-13
Figure 4-1Power input part of the BSC6900.......................................................................................................4-2
Figure 4-2Working principle of power monitoring.............................................................................................4-3
Figure 4-3Working principle of fan monitoring..................................................................................................4-4
Figure 4-4Working principle of environment monitoring...................................................................................4-5
Figure 4-5Structure of the clock synchronization subsystem..............................................................................4-7
Figure 4-6Structure of the clock synchronization subsystem..............................................................................4-8Figure 4-7Process of clock synchronization in the MPS/EPS (1).......................................................................4-9
Figure 4-8Process of clock synchronization in the MPS/EPS (2).....................................................................4-10
Figure 4-9Process of clock synchronization in the TCS...................................................................................4-10
Figure 4-10Dual OM plane...............................................................................................................................4-12
Figure 4-11Structure of the OM network..........................................................................................................4-13
Figure 4-12Principle of effective mode configuration......................................................................................4-17
Figure 4-13Principle of ineffective mode configuration...................................................................................4-17
Figure 4-14Check of the data consistency between the OMU and the host boards..........................................4-19
Figure 4-15Process of collecting performance measurement data periodically................................................4-24
Figure 4-16Alarm management process............................................................................................................4-25
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Figure 4-17Working principle of the alarm box................................................................................................4-26
Figure 4-18Loading process (1)........................................................................................................................4-27
Figure 4-19Loading process (2)........................................................................................................................4-29
Figure 4-20Loading process (3)........................................................................................................................4-30
Figure 4-21Upgrade through the OM network..................................................................................................4-31
Figure 4-22Upgrade process.............................................................................................................................4-32
Figure 5-1Signal flow from CBC-BSC to Abis..................................................................................................5-2
Figure 5-2GSM CS signal flow (1).....................................................................................................................5-3
Figure 5-3GSM CS signal flow (2).....................................................................................................................5-4
Figure 5-4GSM CS signal flow (3).....................................................................................................................5-4
Figure 5-5GSM CS signal flow (4).....................................................................................................................5-5
Figure 5-6GSM CS signal flow (5).....................................................................................................................5-6
Figure 5-7GSM CS signal flow (6).....................................................................................................................5-6
Figure 5-8GSM CS signal flow (7).....................................................................................................................5-7
Figure 5-9GSM CS signal flow (8).....................................................................................................................5-8
Figure 5-10GSM PS signal flow (1)....................................................................................................................5-9
Figure 5-11GSM PS signal flow (2)....................................................................................................................5-9
Figure 5-12Signaling flow on the A interface in A over TDM mode (BM/TC separated)...............................5-11
Figure 5-13Signaling flow on the A interface in A over TDM mode (BM/TC combined)..............................5-11
Figure 5-14Signaling flow on the A interface in A over IP mode....................................................................5-12
Figure 5-15Signaling flow on the Abis interface in Abis over TDM mode......................................................5-13
Figure 5-16Signaling flow on the Abis interface in Abis over IP mode...........................................................5-13
Figure 5-17Signaling flow on the Gb interface.................................................................................................5-14Figure 5-18Signaling flow on the Pb interface.................................................................................................5-15
Figure 5-19OM signal flow (BM/TC separated)...............................................................................................5-16
Figure 5-20OM signal flow (BM/TC combined)..............................................................................................5-17
Figure 6-1TDM-based networking on the A interface in local TCS mode.........................................................6-2
Figure 6-2TDM-based networking on the A interface in remote TCS mode......................................................6-2
Figure 6-3TDM-based networking on the Gb interface......................................................................................6-3
Figure 6-4IPover E1 networking on the A interface..........................................................................................6-3
Figure 6-5IPover Ethernet networking on the A/Gb interface...........................................................................6-4
Figure 6-6TDM-based networking on the Abis interface...................................................................................6-5
Figure 6-7IPover E1 Networking.......................................................................................................................6-5
Figure 6-8IPover Ethernet networking (layer 2)................................................................................................6-6
Figure 6-9IPover Ethernet networking (layer 3)................................................................................................6-6
Figure 6-10TDM-based networking on the Ater interface..................................................................................6-7
Figure 6-11IP-based networking on the Ater interface.......................................................................................6-8
Figure 6-12TDM-based networking on the Pb interface.....................................................................................6-8
Figures
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Tables
Table 3-1Components of the BSC6900 cabinet..................................................................................................3-1
Table 4-1Definitions of the user rights..............................................................................................................4-20
Table 4-2Types of logs......................................................................................................................................4-22
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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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3Overall 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 3-1Components of the BSC6900 cabinet
Component Configuration
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.
NOTE
If customers purchase also the Nastar product of Huawei, customers need to install the SAU board in the MPS
or EPS of the BSC6900 cabinet (the SAU board occupies two slots that work in active/standby mode). For details
on how to install the SAU board, how to install the software on the SAU board, and how to maintain the SAU
board, see the SAU User Guideof Nastar documents.
Software Structure
The software of the BSC6900 has a distributed architecture. It is classified into the host softwareand OMU software.
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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.
Figure 3-1Structure 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, andconfiguration maintenance management software.
l OMU software
The Operation and Maintenance Unit (OMU) software runs on the OMUa board, OMUb
board, and GBAM. The OMU is responsible 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 3-2Structure of the OMU software
Operating system
The Dopra Linux, Suse Linux, or Windows Server 2003 operating system is used.
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, andauthentication process.
3 Overall Structure
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Logical Structure
Figure 3-3and Figure 3-4show the logical structure of the BSC6900.
Figure 3-3Logical structure of MPS/EPS
Figure 3-4Logical structure of TCS
The TCS that forwards the OM signals to other TCSs is called the main TCS.
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The channel for the TCS and the MPS to exchange information varies according to the location
of the TCS: local or remote.
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 3GPPprotocols and processes services of the BSC6900.
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.
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 followingscenarios: 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 3-5and Figure 3-6show the position of the switching subsystem in the MPS/
EPS and TCS respectively, with the modules highlighted in apricot.
Figure 3-5Position of the switching subsystem in the MPS/EPS
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Figure 3-6Position 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 3-7Network 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 3-8Interconnections between subracks through the crossover cables between the SCUa
boards (MPS/EPS)
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Figure 3-9Interconnections 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 3-10Interconnections betweensubracks through the inter-TNUa cables (MPS/EPS)
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Figure 3-11Interconnections 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 3-12shows 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 3-12Service 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 communicate with each other through the switching subsystem
to form a resource pool and perform tasks cooperatively. They can be increased as required,
according to the linear superposition principle, thereby improving the service processing
capability of the BSC6900.
Hardware InvolvedThe 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 3-13and Figure 3-14show the position of the interface processing subsystem
in the BSC6900 system, with the interfaces highlighted in apricot.
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Figure 3-13Position of the interface processing subsystem in the MPS/EPS
Figure 3-14Position 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 and, also hides
differences between them 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 3-15shows the position of the clock synchronization subsystem in the BSC6900 system,
with the clock module highlighted in apricot.
Figure 3-15Position 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:
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l Building Integrated Timing Supply System (BITS) clock
l Global Positioning System (GPS) clock
l External 8 kHz clock
l
LINE clock
The BSC6900 provides reference clock sources for base stations. Clock signals are transmitted
from the BSC6900 to base stations over the Abis interface.
Hardware Involved
The clock synchronization subsystem consists of the GCUa/GCGa board.
3.5 OM Subsystem
The OM subsystem enables the management and maintenance of the BSC6900 in the followingscenarios: routine maintenance, emergency maintenance, upgrade, and capacity expansion.
Position of the OM Subsystem in the BSC6900 System
Figure 3-16shows the position of the OM subsystem in the BSC6900 system, with the OM
module highlighted in apricot.
Figure 3-16Position of the OM subsystem in the BSC6900 system
Functions
The OM subsystem provides:
l 4.4.4 Data Configuration Management
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l 4.4.5 Security Management
l 4.4.6 Performance Management
l 4.4.7 Alarm Management
l
4.4.8 Loading Managementl 4.4.9 Upgrade Management
l 4.4.10 BTS Loading Management
l 4.4.11 BTS Upgrade Management
Hardware Involved
The OM subsystem consists of the OMUa board, OMUb board, or GBAM.
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4Working PrinciplesAbout This Chapter
This chapter describes the working principles of the BSC6900 in the following ways: 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. This 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/GCGa 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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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. Then, it supplies power to all the components in the cabinet.
l The PDB monitors each input in real time. After the PDB detects abnormal power supply,
it reports the relevant alarms to the OMU. The OMU, 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. This subsystem monitors and controls
the power supply, fans, and operating environment.
NOTE
The physical entity of the OMU can be the OMUa board, OMUb board, or GBAM. The following takes the
OMUa board as example to describe environment monitoring.
Power Monitoring
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 4-2shows the working principle of power monitoring.
Figure 4-2Working 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 the
serial port.
2. The signal transfer board transmits the power monitoring signals to the independent fansubrack at the bottom of the cabinet through the monitoring signal cable of the power
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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 generates
alarms and reports the alarms to the OMUa board. The OMUa board then forwards the
alarms to the LMT or M2000.
Fan Monitoring
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 of
the cabinet. This improves the heat dissipation capability of the cabinet.
Figure 4-3shows the working principle of fan monitoring.
Figure 4-3Working 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 independentfan subrack monitor the operating status of the fans in real time and reports the monitoring
signals to the signaltransfer 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 monitoring
signal cable.
3. The SCUa board processes the monitoring signals. If faults occur, the SCUa board generates
alarms and reports them to the OMUa board. The OMUa board then forwards the alarmsto the LMT or M2000.
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Environment Monitoring
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 4-4shows the working principle of environment monitoring.
Figure 4-4Working 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 serial
cable.
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 cableof 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 Ethernet 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 as
follows:
1. The sensors monitor the environment in real time and send the monitoring signals to the
EMU.
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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 SCUa
board in the MPS through the Ethernet cables between the SCUa boards.
4. The SCUa board in the MPS processes the monitoring signals. If faults occur, the SCUaboard 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/GCGa 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 SourcesThe BSC6900 can use the following clock sources: Building Integrated Timing Supply System
(BITS) clock, external 8 kHz clock, LINE clock, and Global Positioning System (GPS) 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, LINE clock, and Global Positioning System (GPS) 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 2Mbit/s clock signals are E1 clock signals, and the 1.5 Mbit/s clock signals are T1
clocksignals.
The BITS clock has two input modes: BITS0 and BITS1. BITS0 and BITS1 correspond
to the CLKIN0 and CLKIN1 ports on the GCUa/GCGa board respectively. The
BSC6900 obtains the BITS clock signals through the CLKIN0 or CLKIN1 port.
l External 8 kHz Clock
Through the COM1 port on the GCUa/GCGa board, the BSC6900 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/GCGa board through the backplane channel. The LINE clock has two input modes:LINE0 and LINE1.
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NOTE
LINE0 and LINE1 correspond to backplane channel 1 and backplane channel 2 respectively.
GPS Clock
The GPS clock provides 1 Pulse Per Second (PPS) clock signals. The BSC6900 obtains the GPS
clock signals from the GPS system. The GCGa board is configured with a GPS card, and the
BSC6900 receives the GPS signals at the ANT port on the GCGa board.
NOTE
The GCUa board is not configured with a GPS card. Therefore, when the BSC6900 is configured with the GCUa
board instead of the GCGa board, the GPS clock is unavailable to the BSC6900.
Local Oscillator
If the BSC6900 fails to obtain any external clock, the BSC6900 can obtain its working clock
signals from the local oscillator.
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 4-5shows the structure of the clock synchronization subsystem.
Figure 4-5Structure of the clock synchronization subsystem
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The structure of the BSC6900 clock synchronization subsystem is described as follows:
l The clock board of the BSC6900 can be the GCUa or GCGa board. The BSC6900 cannot
be configured with both the GCUa and GCGa boards simultaneously. Depending on theclock type, it can have either the GCUa board or the GCGa board.
l If 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/GCGa board.
The clock signals enter the port on the panel of an interface board that can extract line
clock signals. The clock signals are then switched to the GCUa/GCGa board through
the backplane.
The GCUa/GCGa board generates oscillator clock signals.
l If the EPS extracts the clock signals, the interface board that extracts clock signals must be
the EIUa/OIUa/PEUa board.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 4-6shows 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 4-6Structure of the clock synchronization subsystem
The active and standby clock boards in the MPS are connected to the active and standby SCUaboards in the EPS through the Y-shaped clock signal cables. This connection mode ensures that
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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.
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 provided by the clock board. The clock board can extractclock signals from an external device or extract LINE clock signals from the A interface. The
GCGa board can extract clock signals from the GPS.
l Figure 4-7shows the process of clock synchronization in the MPS/EPS when the clock
board extracts clock signals from an external device or from the GPS.
l Figure 4-8shows the process of clock synchronization in the MPS/EPS when the clock
board extracts LINE clock signals from the A interface.
Figure 4-7Process of clock synchronization in the MPS/EPS (1)
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Figure 4-8Process of clock synchronization in the MPS/EPS (2)
As shown in Figure 4-7and 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 GPS clock is used, clock signals travel to the clock
board through the GPS antenna port. 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 the base stations.
Process of Clock Synchronization in the TCS
Figure 4-9shows the process of clock synchronization in the TCS when the TCS extracts LINE
clock signals from the A interface.
Figure 4-9Process of clock synchronization in the TCS
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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 theTCS.
NOTE
l In A over IP over Ethernet mode, the BSC6900 canextract 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 torapidly adjust device status.
4.4.1 Dual OM Plane
The BSC6900 has a dual OM plane to prevent single-point failure from affecting the normal
operation andmaintenance.
4.4.2 OM Network
The OM network of the BSC6900 consists of the M2000, LMT, OMU, 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 ManagementThe alarm management helps you monitor the running status of the BSC6900 and informs you
of faults in real time so that you can take proper 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 Management
The 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 boardsin the BTS.
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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.
Figure 4-10shows this dual OM plane design.
Figure 4-10Dual OM plane
NOTE
If the internal network and external networkare on different network segments, ensure that the two networks
are isolated.
The physical entity of the OMU can be the OMUa board, OMUb board, or GBAM. Both the OMUa board andthe OMUb board can work in active/standby mode. The following takes the OMUa board as example to describe
the dual OM plane.
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 performedautomatically, and the standby OMUa board takes over the OM task. In this case, the
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internal 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, OMU, SCUa boards, and OM
modules in other boards.
NOTE
The physical entity of the OMU can be the OMUa board, OMUb board, or GBAM. The following takes the
OMUa board as example to describe environment monitoring.
Figure 4-11shows the structure of the BSC6900 OM network.
Figure 4-11Structure of the OM network
NOTE
Figure 4-11shows 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 theBSC6900 through Ethernet cables. One M2000 can remotely manage multiple BSC6900s.
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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 the
OMUa 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 OM
network of the BSC6900 is classified into the following networks:
l Internal network: implements the communication between the OMUa board and the hostboards 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 versionupgrade are as follows:
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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 rollback
are as follows:
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 standby
workspaces 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.
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 workspaceof the OMU. On the standby workspaces of the host boards, files can be loaded only from the
standby workspace of the OMU.
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 storingdifferent versions of programs, data, and patch files in the board flash memory.
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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 BoardsBefore 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 standbyworkspaces of another host board. The operation of the active board does not change any
information in the standby board.
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 the
standby workspace of the OMU.
4.4.4 Data Configuration ManagementThe 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 relevantconfiguration 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 or is switched to the effective
mode.
Principle of Effective Mode Configuration
Effective mode configuration is applied to dynamic modification of the BSC6900 configuration
data.
Figure 4-12shows the principle of effective mode configuration.
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Figure 4-12Principle 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 configuration
management module of the OMU.
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 4-13shows the principle of ineffective mode configuration.
Figure 4-13Principle 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.
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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
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 afte