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BSC3000 Customer Product Overview

Document number: PE/BSC/DD/4119Document issue: 03.02 / ENDocument status: StandardDate: 09/September/2005

External document

Copyright2005 Nortel Networks, All Rights Reserved

Printed in France

NORTEL CONFIDENTIAL

The information contained in this document is the property of Nortel Networks. Except as specifically authorized inwriting by Nortel Networks, the holder of this document shall keep the information contained herein confidentialand shall protect same in whole or in part from disclosure and dissemination to third parties and use same forevaluation, operation and maintenance purposes only.

The content of this document is provided for information purposes only and is subject to modification. It does notconstitute any representation or warranty from Nortel Networks as to the content or accuracy of the information

contained herein, including but not limited to the suitability and performances of the product or its intendedapplication.

This is the Way, This is Nortel, Nortel, the Nortel logo, and the Globemark are trademarks of Nortel Networks. Allother trademarks are the property of their owners.

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PE/BSC/DD/4119 01.07 / EN Standard 09/09/2005 Page 2/46

PUBLICATION HISTORY

31/Mar/2000

Issue 01.01 / EN, draftInitial edition for review

02/May/2000

Issue 01.02 / EN, Approved

Edition after review

27/Nov/2000


BSC3000/RNC architecture update. Market models addition

24/Jul/2001

Issue 01.04 / EN, Preliminary

Update with V13.2 content

31/Jul/2001


Update after review

24/Jun/2002


Update

18/Nov/2002


Update (Market models, SW upgrade, shipping configuration, power consumption)

18/March/2005


V15.1.1 Update

09/September/2005


V16.0 Update

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CONTENTS

1. INTRODUCTION.........................................................................................................................6

1.1. OBJECT .................................................................................................................................6

1.2. SCOPE OF THIS DOCUMENT .....................................................................................................6

1.3. RELATED DOCUMENTS ............................................................................................................6

2. GENERAL DESCRIPTION..........................................................................................................7

2.1. ARCHITECTURE &KEY CHARACTERISTICS.................................................................................7

2.2. FUNCTIONAL OVERVIEW ..........................................................................................................9

3. BSS CONFIGURATION............................................................................................................10

4. HARDWARE DESCRIPTION....................................................................................................11

4.1. BSC3000HARDWARE ARCHITECTURE ...................................................................................11

4.2. CONTROL NODE HARDWARE MODULES DESCRIPTION ..............................................................12

4.2.1 Operation and Maintenance Unit (OMU) module ........................................................124.2.2 Mass Memory Storage (MMS) module........................................................................124.2.3 Traffic Management Unit (TMU) module .....................................................................134.2.4 Shelf Interface Module (SIM) or Power Supply ...........................................................13

4.3. INTERFACE NODE HARDWARE MODULES DESCRIPTION.............................................................13

4.3.1 Common Equipment Module (CEM) ...........................................................................134.3.2 ATM Resource Module (ATM RM)..............................................................................14

4.3.3 8K Circuit Switching Matrix Resource Module (RM)....................................................144.3.4 Low Speed Access Resource Complex (LSA RC) ......................................................144.3.5 Shelf Interface Module (SIM) or Power Supply ...........................................................14

5. SOFTWARE DESCRIPTION.....................................................................................................15

5.1. BSC3000SOFTWARE ARCHITECTURE:CN&INCOMMUNICATION ...........................................15

5.2. CONTROL NODE SOFTWARE ARCHITECTURE ..........................................................................16

5.3. INTERFACE NODE SOFTWARE ARCHITECTURE.........................................................................19

6. CAPACITY & CONFIGURATION..............................................................................................21

6.1. GENERAL PRINCIPLES ...........................................................................................................21

6.2. BSC3000MAXIMUM CONFIGURATION ....................................................................................226.3. BSC3000CONFIGURATION EXAMPLES...................................................................................22

6.4. OFFER STRUCTURE .........................................................................................................23

6.5. CAPACITY ............................................................................................................................23

6.5.1 Traffic Profiles.............................................................................................................236.5.2 BSC3000 Capacity for Nortel profiles..........................................................................246.5.3 Impact of GPRS on BSC3000 Capacity ......................................................................25

7. OPERATION & MAINTENANCE ..............................................................................................26

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7.1. CONFIGURATION MANAGEMENT.............................................................................................26

7.1.1 Initialization .................................................................................................................267.1.2 Operation....................................................................................................................26

7.2. PERFORMANCE MANAGEMENT ..............................................................................................27

7.2.1 Observation counters..................................................................................................27

7.2.2 Call trace Management...............................................................................................277.3. FAULT MANAGEMENT............................................................................................................27

7.4. SOFTWARE MANAGEMENT ....................................................................................................28

7.5. OVERLOAD MANAGEMENT .....................................................................................................28

7.6. FAULT TOLERANCE AND REDUNDANCY ...................................................................................29

7.6.1 Redundancy in the control node .................................................................................297.6.2 Redundancy in the Interface node ..............................................................................307.6.3 reliability analysis........................................................................................................31

7.7. LOAD BALANCING .................................................................................................................31

7.8. HARDWARE MANAGEMENT ....................................................................................................33

7.8.1 General principles.......................................................................................................33

7.8.2 Hardware STate detection ..........................................................................................337.8.3 Plug & play..................................................................................................................347.8.4 Object model at OMC-R..............................................................................................357.8.5 LED display.................................................................................................................36

7.9. SOFTWARE UPGRADE ...........................................................................................................36

7.9.1 Software delivery ........................................................................................................367.9.2 BSC downloading from the omc-R..............................................................................367.9.3 upgrade execution ......................................................................................................377.9.4 BTS S/W downloading................................................................................................387.9.5 TCU S/W downloading................................................................................................38

7.10. HARDWARE UPGRADE...........................................................................................................39

7.10.1 TMU extension............................................................................................................397.10.2 LSA extension.............................................................................................................39

7.11. UPGRADE OF A BSC2GBY A BSC3000 ...............................................................................397.12. TML(LOCAL MAITENANCE TERMINAL).....................................................................................39

7.12.1 Equipment and interface.............................................................................................397.12.2 TML functions .............................................................................................................40

8. INTERFACES............................................................................................................................40

8.1. ABIS,ATER,AGPRS AND AINTERFACES .................................................................................40

8.2. BSC3000CLOCK SYNCHRONIZATION.....................................................................................40

8.3. BSC3000/OMC-RINTERFACE ............................................................................................41

9. PACKAGING & INSTALLATION..............................................................................................42

9.1. PHYSICAL CHARACTERISTICS ................................................................................................42

9.1.1 Dimensions and Weight ..............................................................................................429.1.2 Power supply ..............................................................................................................42

9.2. SHIPMENT ............................................................................................................................43

9.3. INSTALLATION ......................................................................................................................43

9.3.1 Environmental conditions............................................................................................439.3.2 Floor ...........................................................................................................................439.3.3 Clearance ...................................................................................................................43

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10. REGULATORY COMPLIANCE.................................................................................................44

10.1. ENVIRONMENTAL CONDITIONS ...............................................................................................44

10.2. ELECTROMAGNETIC (EMC)AND ELECTROSTATIC CONDITIONS .................................................44

10.3. ACOUSTIC REQUIREMENTS ....................................................................................................44

10.4. SECURITY REQUIREMENTS ....................................................................................................44

11. ABBREVIATIONS.....................................................................................................................45

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1. INTRODUCTION

1.1. OBJECT

The BSC3000 is Nortel Base Station Controller product for the GSM market. It replacesprevious generations of GSM BSC products (BSC12000) and introduces a dramatic increasein capacity per node, while supporting the evolved functionalities required by the GSMmarket.

1.2. SCOPE OF THIS DOCUMENT

This document provides an overview of the BSC3000 product: hardware architecture and

functional description. It is mainly targeted for use by the marketing and sales departmentsbut can also be useful for anybody who wants to get a good global understanding of the

Nortel new generation BSC product.

1.3. RELATED DOCUMENTS

[A1] PE/TCU/DD/160 TCU3000 Customer product overview

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2. GENERAL DESCRIPTION

2.1. ARCHITECTURE & KEY CHARACTERISTICS

The BSC3000 is built with 2 Nortel multi-application platforms: a high processing, fault-tolerant, ATM-based, future proof platform (Control Node) and a high-performance circuitswitch platform (Spectrum Interface Node) providing dense PCM connectivity. Those 2platforms are packaged in one single frame, providing a 1-cabinet modular and high capacityBSC. The Control Node and Interface Node are interconnected by a dual ATM/OC-3 fiber

optic cable.

The key characteristics of the product are the following:

Very high and scalable capacity products:

From 600 E up to 3000 E(1)

in 1 cabinet. The BSC3000 can manage up to 1000 TRXs,500 BTSs and 600 cells. Its maximum external PCM connectivity is 126 E1 or 168 T1PCMs.

Very high reliability: the BSC3000, built on a Nortel switching platform, is designed to provide a switch classavailability. The availability target is 99.999% or 3 minutes of downtime on average peryear per system. All hardware modules are totally redundant (either 1+1 or N+Predundancy scheme), including the PCM interface boards. In addition, the Control Node(in charge of call processing and OA&M) of the BSC3000 implements a fault tolerantarchitecture, based on redundancy of processes and a load balancing mechanism onthe processors, allowing fast recovery of service after a hardware failure.

High performance and cost-effective operation and maintenance: The BSC3000 by its high density, offers a significant footprint reduction for high capacity

compared to 2G products (6 times less for a 3000E configuration), and consume lesspower (3 times less per Erlang).The software upgrade of a BSS network will be faster with BSC3000, because theBSC3000 can download more BTSs in parallel than a BSC 2G. Key features such asplug & play hardware modules, a local or remote maintenance terminal, and precisefault detection and reporting make the maintenance of BSC3000 equipment costeffective.

The Figure 1 shows the BSC3000 cabinet structure. The cabinet is made of a frame and aPCM cabling attachment offering front access to the PCM connections. This attachment is

called Service Area Interface (SAI). The BSC frame is made of the Control Node dual-shelfand the Interface Node dual-shelf.

1

1Based on Nortel call profiles. Actual value dependant on actual call profile.

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ControlNode

Interface

Node

Service

AreaInterface

Figure 1: BSC3000 cabinet structure

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2.2. FUNCTIONAL OVERVIEW

In the BSS network, the BSC3000 performs tasks related to the BSS equipmentmanagement & supervision and to the GSM call processing, mainly:

BTS supervision

Radio channel allocation

Radio channel monitoring

Traffic management

TCU management

OMC-R link management

Handover procedures

Operation and maintenance request from the OMC-R processing

BSS configuration data and software storage

BSS performance counters management

Failure detection and processing

The BSC3000 offers a set of high value product specific features: fault tolerance, loadbalancing, hardware management (plug & play modules, remote actions...), remotemaintenance terminal via TCP/IP. Those differentiating features are described in details in

section 9, Operation & Maintenance.

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3. BSS CONFIGURATION

The figure 2 describes a BSS network. A BSC3000 can manage both TCU3000 and TCU2G.

Note that the OMC-R/BSC3000 link is based on TCP/IP over Ethernet (instead of X25 for

BSC 2G).

OMC-ROMC-R

BSC2GBSC2G

TCUe3TCU3000

TCU2GTCU2G

BSCe3BSC3000 BSCe3BSC3000

BTSsBTSs

TCU2GTCU2G

X25X25EthernetEthernet

BTSsBTSs

PCUPCU

Figure 2: Mixed BSC2G/BSC3000 BSS network

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4. HARDWARE DESCRIPTION

This chapter provides a general overview of the BSC3000 H/W architecture. It also providesa more specific description of each of the modules of the BSC3000. Please note that thosemodules characteristics may evolve as part of the normal product evolution and H/W life-cycle management.

4.1. BSC3000 HARDWARE ARCHITECTURE

The BSC3000 is a one-cabinet equipment, composed of 2 shelves and 1 Service AreaInterface that provides front access to the PCM cabling. The 2 shelves are the Control Nodeand the Interface Node.

The Control Node is a high processing, ATM-based engine that ensures the GSM call &signalling processing and the OA&M of the BSS. It is connected to the Interface Node by an

optical fibre cable with a standard ATM interface.

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(CN & IN)

Figure 3: BSC3000 architecture and board layout

The Interface Node is a multi-application Nortel platform (called Spectrum), that provides theE1 or T1 PCM connectivity and the circuit switching functions.

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Each board of the BSC is enclosed in a metallic housing, providing a single level of EMCshielding, noise protection and other environmental parameter controls. The circuit packs

plus the metallic housing is called a hardware module. The different hardware modules ofthe BSC present the same and consistent faceplate with 2 LEDs (green and red) for easy onsite maintenance.

All hardware modules in the BSC3000 are redundant. Different types of redundancy areimplemented: N+P (or load sharing) or 1+1 (either in active/passive mode or in parallelprocessing mode). See 7.6. Fault tolerance and redundancy for detailed information.

4.2. CONTROL NODE HARDWARE MODULES DESCRIPTION

4.2.1 OPERATION AND MAINTENANCE UNIT (OMU) MODULE

The OMU is responsible for the following functions:

Contro l of all BSC elements (both Control and Interface Nodes) Disk management Ethernet access to OMC-R and TML OA&M of the BSS

The OMU module processor is a Motorola PowerPC 604 at 400 MHz and with 256 Mb ofRAM. The OMU runs the AIX operating system.

The OMU is provisioned in a 1+1 hot stand-by redundancy scheme.

4.2.2 MASS MEMORY STORAGE (MMS) MODULE

The MMS (or disk) is a SCSI-2 disk. There are 4 disks in the BSC: each OMU has a private

disk to store the Operating System and system data; 2 additional redundant disks store theBSS database and GSM data. These disks are connected to both OMUs: at any given timethe active OMU controls both disks.

Two versions of the MMS board are supported in BSSV16: MMS1 and MMS2 (planned).

Both can be mixed inside a same BSC, provided the following sparing rules are followed:

an MMS1 can be replaced by an MMS1 or an MMS2

an MMS2 can only be replaced by an MMS2.

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4.2.3 TRAFFIC MANAGEMENT UNIT (TMU) MODULE

The TMU is responsible for the following functions:

GSM traffic management GSM signaling processing (LAPD & SS7) BTS OA&M (software downloading, BTS configuration)

The Control Node can host a maximum of 14 TMUs. 2 TMUs are dedicated to support SS7signalling and operates in 1+1 redundancy scheme. The other TMUs (up to 12) are availablefor traffic Management and operates in an N+P load sharing redundancy scheme.

In BSSV16, the TMU board exists in two versions: TMU1 and TMU2. The TMU2 provideshigher level of performances (at board level) than the previous version of the board (TMU1).From V16 included, mixed TMU1/TMU2 configurations inside a same BSC are supported.

Please refer to Nortel engineering documents for the related allowed configurations.

4.2.3.1 TMU1

The TMU1 processing board itself is made of the VME SBC and a PCI Mezzanine Card(PMC) daughter board. The TMU1-SBC processor is a Motorola PowerPC 603e at 200 MHzwith 32 Mb of RAM. The TMU1 PMC processor is a Motorola Power Quick MPC 860. TheTMU1 runs VxWorks operating system.

4.2.3.2 TMU2

The TMU2-TM uses an MPC8560 (PowerQuicc III) from Motorola, running at 833 MHz. Thisprocessor is in charge of all processing tasks previously performed by the three processorsof the TMU1.ATM switch or Communication Controller (CC) module

The CC is an ATM switch that acts as the back-panel for the Control Node. It provides a high

performance interconnection between the OMU and TMU modules, as well as the ATM onOC-3 connectivity towards the Interface Node.

The CC is provisioned in a 1+1 redundancy scheme, with both CCs working simultaneously.

4.2.4 SHELF INTERFACE MODULE (SIM) OR POWER SUPPLY

The SIM module provides 48V power supply to the Control Node shelf. There are 2 SIMssimultaneously active to ensure redundancy.

4.3. INTERFACE NODE HARDWARE MODULES DESCRIPTION

The Interface Node is composed of a controller (CEM) and a set of resource modules (RM)that are connected point-to-point to the CEM through the back-panel and communicate via aproprietary communication protocol called s-link. This is the base architecture of Spectrum.

4.3.1 COMMON EQUIPMENT MODULE (CEM)

The CEM controls the Interface Node resource modules, provides the OA&M interface of theSpectrum platform, as well as the clock synchronization and 64 kbps traffic switching.

The CEM is provisioned in a 1+1 hot stand-by redundancy scheme.

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The CEM also provides connectivity for DS512 (fibre) links to the 8k-RM. Those links areoptionally used to increase the switching capacity of the BSC3000. Each CEM supports amaximum of 4 DS512 links connected to a single SRT board.

4.3.2 ATM RESOURCE MODULE (ATM RM)

The ATM RM performs the adaptation between the Control Node ATM cells and theInterface Node DS0 (64 kbps) circuits. It provides AAL-1 adaptation to transport LAPD andSS7 links and AAL-5 adaptation to transport OA&M and call processing signalling betweenthe Control Node and Interface Node.

The ATM RM is provisioned in a 1+1 redundancy scheme, with both modules workingsimultaneously.

4.3.3 8K CIRCUIT SWITCHING MATRIX RESOURCE MODULE (RM)

The 8K RM provides subrate switching capability, as the CEM is able to switch at DS0 (64kbps) level only. It can switch at 8, 16, 32 and 64 kbps PCM channels.

The 8K RM is provisioned in a 1+1 hot stand-by redundancy scheme.

The 8k RM also provides connectivity for DS512 (fibre) links to the CEM. Those links areoptionally used to increase the switching capacity of the BSC3000. Each 8k RM supports amaximum of 4 DS512 links connected to a single CEM board.

4.3.4 LOW SPEED ACCESS RESOURCE COMPLEX (LSA RC)

The LSA is the PCM interface module. It is called resource complex, because it is made of

3 boards on a mini-back plane, taking 3 slots: 2 IEM (Interface Electronic Module) that are in1+1 hot stand-by redundancy and 1 TIM (Terminal Interface Module) that is a passive

interconnect module that routes the PCM towards the active IEM. The TIM does not containactive electronic components and has a very high MTBF. Hence even the LSA providesinternal redundancy.

The BSC Interface Node can have up to 6 LSAs. Each LSA can manage up to 21 E1 or 28

T1 PCMs. The second LSA in the lower shelf of the Interface Node (slots 4, 5 & 6) ismandatory because the clock synchronization of the BSC3000 on Ater interface is done withthe PCM managed by that LSA.

Each LSA is associated to a CTU (Cable Termination Unit) that is housed in the SAI andprovides copper concentration. The CTU provides the ability for each E1 or T1 PCM to beput in loopback mode, in order to help the diagnostic of PCM faults. The SAI is a 30cm widthcabinet that is attached to the BSC cabinet, enabling front access to the PCM cabling. It can

host up to 8 CTUs.In BSSV16, the IEM board exists in two versions: IEM1 and IEM2. The two versions of theboard can be mixed inside a same LSA or BSC. Sparing rules remain unchanged.

4.3.5 SHELF INTERFACE MODULE (SIM) OR POWER SUPPLY

The SIM module provides 48V power supply to the Control Node shelf. There are 2 SIMs

simultaneously active to ensure redundancy.

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5. SOFTWARE DESCRIPTION

5.1. BSC3000 SOFTWARE ARCHITECTURE: CN & INCOMMUNICATION

The BSC3000 software architecture can be split in 2 parts, mapping the hardwarearchitecture: the Control Node (CN) software and the Interface Node (IN) software. Bothapplications are linked through the IN-access application running on the OMU and TMUand the CN-access application running on the CEM.

The IN-OAM application running on OMU communicates with the Interface Node via thispath, for management purpose. The Traffic Management and the BTS-OAM applicationsrunning on the TMUs communicate as well directly with the Interface Node for the trafficmanagement (connection establishments, traffic switching) and for BTS management.

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Figure 4: CN & IN communication

The messages between the Control Node and the Interface Node are sent with IP protocolencapsulated in ATM AAL-5. The LAPD and SS7 links are conveyed with ATM AAL-1circuits.

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5.2. CONTROL NODE SOFTWARE ARCHITECTURE

The Control Node software architecture is structured around a layer-model presented in the

figure below:

Hardware

Hardware Abs t rac t i on l aye r

Co re l aye r

C o m m o n l a y er

A p p l ic at io n & Serv ic es lay er

Figure 5: CN layered software architecture

the Hardwarelayer is the base software/firmware linked to the hardwaremodule

the Hardware Abstractionlayer is in charge of making the upper layersindependent of the hardware

the Core layer is made of the standard and off-the-shelf software running onthe Operating System (the OS are AIX for OMU)

the Commonlayer is in charge of the management of the platform: platformOA&M and supervision services, Fault tolerance services, Communicationlibraries... The Common layer is actually split into the Control Node platformpart and the BSC platform part.

the Application & Servicelayer is a set of functional entities making up the

GSM BSC applications, such as Traffic Management, BTS management, TCUmanagement, GSM interface management (Ab is, Ater, Agprs , A).

This layered software architecture is implemented in each Control Node hardware module:OMU, TMU, CC.

There are 2 types of applications that run on the Control Node:

Platform OA&M applications: for eg. ADM, IN-OAM, CN-OAM, BTS-OAM... Traffic Management: different applications making up the GSM call

processing

The figures below present the functional architecture of the OMU and TMU modules. Theyshow the main applications and software entities and how they fit in the layered architecture.The purpose is not to describe in an exhaustive way all software blocks making up theBSC3000 product, but give a high level view of the software architecture.

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OMU (SBC) func t iona l a rch i tec tu re

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A DM

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IN-OA M TN-OA M

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Com mo n layer (BSC p la t fo rm)

Com mo n layer (CN p la tfo rm)

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Hard w Mg t So ftw Mg t

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Core layer (Operat ing System )

A IX L ib rair ies

Hardware Abs t rac t ion layer

OS KernelB SP

Hardw are layer

A -acc A ter-acc A g p rs -acc

Figure 6: OMU software architecture

ADM: Manages the object model in the BSC & interfaces with the different OAMapplications as well as with the OMC-R

IN-OAM: In charge of start-up, upgrade, supervision, OA&M of the BSC InterfaceNode

TN-OAM: In charge of start-up, upgrade, supervision, OA&M of the Transcoding Node

A-access: Management of SS7 and A-interface

Ater-acc & Agprs-acc: Management of LAPD and Ater & Agprs interfaces

IN-access: Communication interface to the Interface Node

CN-OAM: OA&M of the Control Node interfaces with OMU, TMU & CC OAMapplications

OAMservices : Set of OAM applications: configuration, fault, performance...

Test&Diag : Interfaces with TML for the tests applications of the CN, IN and BSC

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APE: Association and transport connection management between the OMC-R andBSC

OSIAM: Communication stack for OMC-R/BSC communication

SS7-ADM: SCCP and MTPx layers management

TMU (SBC) funct ional architecture

Service & Application layer (GSM)

OAM Services

LAPD-accessTraffic Mgt BTS-OAM

IN-access

Common layer (BSC platform)

Common layer (CN platform)

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SS7-ADMFault Mgt

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Hardw Mgt Sof tw Mgt

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Perf Mgt

Fault ToleranceConfig Mgt

Core layer (Operating System)

VxWorks Librairies

Hardware Abstraction layer

OS KernelBSP

Hardware layer

SS7-access

Figure 7: TMU software architecture

Traffic Mgt: Set of applications making up the GSM Call processing (radio & terrestrialresource mgt, layer 1, connection & mobility management...)

BTS-OAM: Configuration, upgrade, supervision, OA&M of the BTS

LAPD-access: provisioning and management of the Abis LAPD connections

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SS7-access: SS7 links management

IN-access: Communication interface to the Interface Node

OAMservices : Set of OAM applications: configuration, fault, performance...

LAPD: LAPD protocol management (actually running on the PMC board)

SS7-ADM: SCCP and MTPx layers management

5.3. INTERFACE NODE SOFTWARE ARCHITECTURE

The figure below describes the Interface Node software architecture, mapped on thedifferent hardware modules.

Switch Mgt

CEM

IN-OAM

CN-ACCESS

LSA

RM-OAM

Carrier

Maintenance

ATM RM

ATM Mgt

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AAL5

8K RM

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control

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timeswitchchannels

Figure 8: IN software architecture

IN-OAM: Configuration, upgrade, supervision, defense of the Interface Nodeelements. It interfaces with the different OAM applications in the IN modules and as well aswith the IN-OAM application in the OMU (Control Node).

Switch Mgt: Entity responsible for establishing connections for bearer and signallingchannels on the CEM timeswitch and on the 8K RM sub-rate timeswitch. It receives theconnection messages from the Control Node Traffic Mgt application.

CN-access: Manages the communication between the CN and IN, through the ATM RM

AAL5 application. It dispatches the messages to the IN OAM or to the Switch Managementapplications.

RM OAM: Generic management entity common to all RM. It performs the managementfunctions for the RM: configuration, fault, performance...

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6. CAPACITY & CONFIGURATION

This chapter provides general information on the capacity and possible configurations of theBSC3000. For complete and detailed information, as well as for any actual node engineeringactivity, please refer to Nortel BSS Engineering Rules.

6.1. GENERAL PRINCIPLES

In terms of product configurations, the BSC3000 product offers both modularity andflexibility:

Modularity: the BSC3000 is modular in terms of processing and connectivity, so that ifmore processing power or more connectivity is required one or several modules have

just to be added.

The modules that ensure the modularity of the BSC are the following: TMU (Traffic Management Unit): in charge of GSM traffic and signalling

processing. The TMU provides the modularity in capacity and in signallinglinks.

LSA (Low Speed Access): PCM interface module. The LSA provides themodularity in PCM connectivity: up to 21 E1 or 28 T1 per LSA.

Flexibility:A set of product configurations fitting closely the need of a given customer interms of processing, signalling, PCM connectivity can be delivered, given that thoseconfigurations remain within the minimum and maximum product configurations.

For example, if a 2000 Erlang BSC with the same PCM and signalling connectivity isdelivered to 2 customers having networks with different traffic profiles, the number of TMUsin each BSC can be different.

A rural type of configuration can also be defined, with a relatively low number of TMUs(because the traffic capacity is low) and a maximum number of LSAs (because many smallBTSs used for coverage need to be connected).

On the other hand, we could have an urban type of configuration with a high number ofTMUs (high traffic capacity) and a relatively low number of LSAs (because BTSs have manyTRXs per cell, and there are relatively few BTSs to be connected to the BSC).

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6.2. BSC3000 MAXIMUM CONFIGURATION

The table below gives the dimensioning factors for the BSC3000 in maximum configuration.

The maximum configuration is a 3000 E BSC, which translates to 14 TMU1 (respectively 9TMU2) modules and 6 LSAs (126 E1 or 168 T1 PCMs). In that case the BSC will require 2TCU3000.

The 14 TMU1s are respectively :

12 (10+2 for redundancy) for traffic management

2 (in 1+1 redundancy scheme) to support SS7 signalling.

The 9 TMU2s are respectively :

7 (6+1 for redundancy) for traffic management

2 (in 1+1 redundancy scheme) to support SS7 signalling.

Note that the maximum Erlang capacity of the BSC3000 is subject to such parametersas subscriber call profile or connectivity.

6.3. BSC3000 CONFIGURATION EXAMPLES

The table below gives some examples of BSC configurations, based on the TMU1. TheErlang capacity of the BSC is given for Nortel traffic profiles (e.g. short call or high mobility

type).

BSC 600 E 1500 E 2400 E 3000 E

TMU1 traffic 2+1 5+1 8+2 10+2

TMU2 traffic 2+1 3+1 5+1 6+1

TMU SS7 1+1 1+1 1+1 1+1

LSA 2 3 5 6

B S C 3 00 0 d i m e n s i o n i n g M a x C o n f i g .

Erlang 3000T R X 1000BT S 500Cells 600LAP D l inks 567E1/T1 PC M 126/168A-interface circui ts 3100SS 7 l inks 16

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6.4. OFFER STRUCTURE

The BSC3000 offer structure is based on :

- a generic Base Package, which consists of a fully equipped BSC3000 with minimal TMUconfiguration and no LSA,

- additional TMU modules for traffic capacity extension up to 3000 erlangs

- additional LSA modules with PCM cables (up to 6 LSA modules), for PCM connectivity.Note that there are 3 LSA upgrade kit versions : E1 75 Ohms, E1 120 Ohms and T1.

6.5. CAPACITY

WARNING: The customer detailed traffic model and all engineering parameters are necessary tocompute the exact erlang capacity of the BSC3000. The capacity figures given in this section arecomputed for a model network (not real and not including all engineering parameters) and for the 3Nortel traffic profiles. These figures shall not be used in any case to dimension the BSCs for a realnetwork. The engineering documents written for each specific network are the reference for BSC

capacity in that network.

6.5.1 TRAFFIC PROFILES

The following table describes the 3 Nortel traffic profiles used to calculate the BSC3000 erlangcapacity. The High mobility and Short call traffic profiles are tougher respectively in mobilityparameters and call duration parameters, than what is encountered in most of Nortel customer

networks.

Nortel Call ProfileParameter Definition

StandardHigh

MobilityShortCall

Number of active (attached) subscribers in the LAC 40000 40000 40000Mean Number of cells per BSC 300 300 300Mean MSC Paging repetition (%) 10,00%

Bloking Rate on TCH (%) 2,00% 2,00% 2,00%Bloking Rate on SDCH (%) 0,10% 0,10% 0,10%

Total 2,00% 2,00% 2,00%

Selection Phase 1,00% 1,00% 1,00%

Percentage of HO failure

Execution Phase 1,00% 1,00% 1,00%Percentage of Double Allocation 5,00% 5,00% 5,00%Mean Duration of successfull call (TCH) (s) 120 120 45Mean Duration No Response call (s) 20 20 20Mean Duration of Busy call (s) 0 0 0Mean Call Duration (s) 92,18 92,18 35,82Average traffic / Subscriber / BH (Erl) 0,02500 0,02500 0,02200

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Mean Duration on SDCCH channel (s) 4 4 4BHCA per Subscriber 1 1 2,25

Total 65,00% 65,00% 65,00%

% of Succ call 70,00% 70,00% 70,00%% of No response call 10,00% 10,00% 10,00%

% of MOC

% of Busy call 20,00% 20,00% 20,00%Total 33,00% 33,00% 33,00%

% of Succ call 85,00% 85,00% 85,00%% of No response call 10,00% 10,00% 10,00%

% of MTC

% of No response to Paging 5,00% 5,00% 5,00%Total 2,00% 2,00% 2,00%

% of Succ call 80,00% 80,00% 80,00%% of No response call 10,00% 10,00% 10,00%% of Busy call 5,00% 5,00% 5,00%

% of MtoM

% of No response to Paging 5,00% 5,00% 5,00%

HO inter BSC / call 0,25 0,70 0,25

HO intercell intra BSC / call 0,65 2,50 0,65HO intra cell / call 0,74 2,74 0,74

Handovers (/ call)

Total HO / call 1,64 5,94 1,64HO inter BSC / subs / BH 0,250 0,700 0,563HO intracell intra BSC / subs /BH 0,650 2,500 1,463HO intra cell / subs / BH 0,740 2,740 1,665

Handovers (/ subs / BH)

Total HO / subs / BH 1,640 5,940 3,690Number of LU (non periodic) / subs / BH 0,80 2,50 0,80Number of periodic LU / subs /BH 0,20 1,00 0,20Number of detach / subs / BH 0,35 0,45 0,35Number of attach / subs / BH 0,35 0,45 0,35

Number of SMS-MT / Subs / BH (including VMS) 0,11 0,11 0,11Number of SMS-MO / Subs / BH 0,00 0,00 0,00

mean Number of messages per cell (min=1 max=5) 1 1 1

Repetition Rate (6, 30, 60, 120, 240, 480, 960, 1920) (s) 30 30 30Periodicity of Identification Procedure (%) 20,00% 20,00% 20,00%Periodicity of Authentication Procedure (%) 20,00% 20,00% 20,00%

RF_RES_IND rate (n * 480 ms) 16 16 16Mean Number of TRX per Cell 2 2 2

6.5.2 BSC3000 CAPACITY FOR NORTEL PROFILESThe following table shows the estimated erlang capacity of BSC3000 for Nortel call profiles.

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BSC3000 capacity Standard High Mobility Short CallProfile Profile Profile

2+1 TMU1 Erlang 600 600 6002+1 TMU2 BHCA 24 000 24 000 54 000

5+1 TMU1 Erlang 1 500 1 500 1 5003+1 TMU2 BHCA 60 000 60 000 135 00010+2 TMU1 Erlang 3 000 3 000 3 0006+1 TMU2 BHCA 120 000 120 000 270 000

Note1: 2 additional TMUs are required to support SS7 signalling (in 1+1 redundancy

scheme)

6.5.3 IMPACT OF GPRS ON BSC3000 CAPACITY

GPRS entails no significant BSC capacity decrease in terms of processing. In other words,

the processing power of the TMU and of the other processing boards is not typically alimiting factor for GPRS dimensioning.

The PCM connectivity (Abis+Ater+Agprs) and the circuit switching capacity of the BSC3000shall have to be taken into account for GSM & GPRS network engineering.

In urban areas, the BSC3000 shall typically have enough PCM available so that the GPRSintroduction can be done without any PCM dimensioning constraints. For example, a

maximum capacity BSC3000 managing a BSS network made of mainly S444 BTS, will needaround 90 PCM for Abis and Ater, out of 126.

In rural areas (BTS S111 & S222), all PCM might be used for voice service only. The

introduction of GPRS can then impact the BSC3000 capacity in terms of number of managedBTS & TRX.

The maximum circuit switching capacity of the BSC3000 (2268 64-kbps circuits) shall be

taken into account in the dimensioning of a voice + GPRS network. The switching capacity isnot a limitation for voice only and for low speed GPRS services (CS1/CS2). For high speeddata services (GPRS CS3/CS4 & EDGE), since the radio time-slots carrying those services

require more circuits on Abis and Agprs (2 to 4 times more than for voice and low speedpacket data), the BSC3000 switching capacity limit can be reached for some networkconfigurations, especially for high data penetration (for e.g. 8 radio TS per cell for GPRS).The impact on BSC3000 capacity in terms of number of managed TRX has to be determinedon a case by case basis, according to the network configuration. In this scenario, theaddition of DS512 fibre links (and activation of the corresponding feature) can be used toincrease the switching capacity of the BSC3000 (up to 4056 DS0s).

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7. OPERATION & MAINTENANCE

The BSC is the core element for the operation & maintenance of the BSS network: itmanages the BTS and the TCU and interacts with the OMC-R to report to the operator themanagement & supervision information, as well as to take into account the commands &inputs of the operator.

The BSC3000 provides all the classical O&M functions for the BSS network: configurationmanagement, performance management (observation counters & call trace), fault

management, software management, overload management. In this section, those functionsare recalled briefly.

Then we focus on the high value specific features provided by the BSC3000 in the operation

& maintenance domain:

fault tolerance: carrier grade availability, precise and fast fault detection andrecovery load balancing: automatic distr ibution of the traffic processing load on the

TMU modules hardware management: plug&play hardware modules, hardware

representation at the OMC-R, remote hardware tests... new TML: java based, remote connection via TCP/IP

Note that the BSC3000 does not provide interfaces for external alarms management.

7.1. CONFIGURATION MANAGEMENT

7.1.1 INITIALIZATION

The OMC-R is in charge of the BSC initialization. The operator creates a logical bsc objectat the OMC-R. When the BSC-OMC communication is established, the BSC3000 sends to

the OMC-R its hardware configuration: auto-discovery and representation at the OMC-R HMIof the actual hardware configuration of the BSC3000 (see 7.8 HARDWAREMANAGEMENT).

7.1.2 OPERATION

The BSS configuration set of commands allows an OMC-R user to create a BSS network, toupdate it by creating new elements, modifying or deleting the existing ones, and to get alluseful information about all elements in the BSS network managed by the OMC-R

(equipment and links between them). Hardware configuration requests and BSC Q3 objectactions are performed from the OMC-R.

The main difference from the BSC2G, is the modelisation of the hardware modules of theBSC3000 & TCU3000. The operator has a view of the hardware equipment from the OMC-R(except for SIMs, FANs and PCIU). The hardware faults are notified and displayed directlyon the related module.

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7.2. PERFORMANCE MANAGEMENT

7.2.1 OBSERVATION COUNTERS

The GSM BSS observation counters are collected and reported to the OMC-R: the countersare grouped in 4 types of permanent observations:

Real Time Observations: a small set of counters can be displayed in real time for networksupervision.

Diagnostic Observations: allows launching observations on a small set of cells with a largeset of counters.

Fast Statistic Observations: allows making statistics on a 15 min to 1 hour basis.

General Statistic Observations: allows making statistics on a per-day basis.

The equipment specific counters (e.g. processor load) are provided for BSC3000, for OMU,TMU and CEM modules.

N.B. : there are no temporary observations for BSC3000

(Abis level 1(HDLC), Abis level 2 and SS7 counters are not supported)

7.2.2 CALL TRACE MANAGEMENT

The Call Trace function is the GSM 12.08 trace facility of the BSC. It enables to trace theactivities associated with specific communications in a BSC (in fact to trace specificsubscribers (IMSI) or specific equipment (IMEI)), and to transfer these data to the associatedOMC-R. This function is initiated at OMC-S level, through MMI-commands to allow a trace

record to be produced for a particular IMSI or IMEI. When a trace is invoked in a BSS,BSSMAP MSC INVOKE TRACE message is sent by the MSC to the BSC. On receipt of this

message, the BSC starts tracing the specified call.

The Call Path Trace function allows tracing of communications which take place on specificresources of the BSS ( CICs, TRXs or Cells).

A session of Call Path Trace is initiated in the BSC by the OMC-R.

7.3. FAULT MANAGEMENT

The Fault Management application of the BSC3000 in charge of:

the detection of faults on software, firmware or hardware entities of the BSC

the management of BTS and TCU faults

the precise diagnostic of the fault

the notification of the fault to a master entity, if needed

the action to be taken to correct the fault

the logging on disk of all the faults for debug purpose (new feature in BSC3000 toenhance maintenance and support).

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The Fault Management application is hierarchically structured: processor level, module level,Interface Node level, Control Node level and BSC level. Each level is able to detect, analyze,filter and report the faults to the master (or upper) level, as well as take the appropriate

defense action if any. This hierarchical structure ensures an efficient management of thefaults within the system, in terms of precise fault detection and reporting, and fast recovery.

The master module for Fault management of the Control Node and of the BSC is the OMU.

The master module for the Interface Node is the CEM. The CEM reports to the OMU thefaults related to the Interface Node. The OMU module stores the fault events on circular filesand send them to the OMC-R. It logs also the faults on disk for debug purpose.

The fault events sent to the OMC-R contains information for supervision and maintenance:type of fault, criticity, service impact, impacted hardware. Hardware failures are notifieddirectly on the related hardware module, so that the OMC-R can display precisely to the

operator the failed equipment.

7.4. SOFTWARE MANAGEMENT

The BSS software (BSC, TCU & BTS software) is downloaded to the BSC from the OMC-R.It is compressed and divided into several files, in order to download only the modified files

between two versions and to reduce as much as possible the downloading duration.

The BSC3000 stores two versions of the BSS software. The new version can be downloadedin background, without impacting the BSC service.

The BSS software can be installed also locally from the TML (requires a service interruption).

See 9.9. Software upgrade for more details on the software management and upgrade.

7.5. OVERLOAD MANAGEMENT

The BSC3000 robustness in overload conditions is ensured by a centralised overload controlmechanism, which is based on the same principles as for the overload control implementedfor BSC 2G.

The modules monitored by the overload function are the TMU (in charge of all traffic &signalling processing) and the CEM.

Note: The OMU & CC modules are not involved in the GSM traffic processing, so their

load is not impacted by the traffic level variations.

For TMU and CEM boards, the critical resources are monitored: CPU load, memory poolsoccupancy, messaging mailboxes occupancy. Those parameters are used to compute asynthetic load of the module. Each module reports its synthetic load to the OMU, which

controls globally the load state of the BSC and triggers the appropriate actions according to

the boards that are in overload and to the level of overload.

When a TMU is in overload, it will filter partially the new coming traffic requests related to thegroup of cells it manages. Counters giving the processor synthetic loads and the number offiltered operations by type are provided. Those counters give the operator a detailed view of

the filtered traffic and processor loads during overload conditions, allowing him to plan theBSC capacity evolution in its network.

The overload thresholds are determined by the processorLoadSupConf parameter, as forBSC 2G. One nominal value will be used for this parameter. To the value of this parameter

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are associated the sets of overload thresholds for each monitored processing modules. Thisnominal value ensures both the BSC3000 robustness and a nominal level of carried traffic.

Three overload levels are defined in the BSC. Each level corresponds to the load level of the

BSC processors. According to the overload level, some of the new traffic requests arefiltered:

overLoad level 1 (80% of synthetic load): traffic reduction around 33% by filtering 1request out of 3 of the following messages:

- Paging Request, - Channel Request with cause different from Emergency call , -Al l Firs t Layer 3 messages with cause d if ferent from Emergency

call , - HandOver for traffic reason, - HandOver fo r O&M reason, - directed retry.

overLoad level 2 (90% of synthetic load): traffic reduction around 66% by filtering 2requests out of 3 of the above messages.

overLoad level 3 (100% of synthetic load): no new traffic is accepted by filtering allprevious and following messages:- All First Layer 3 messages,

- All Channel Request (including cause for Emergency Call),

- All Handover Indication,- All Handover Request.

7.6. FAULT TOLERANCE AND REDUNDANCY

The BSC3000 is designed to provide carrier grade availability. All hardware modules aretotally redundant, including PCM interface modules. But unlike the current 2G BSC, total

duplication of all critical BSC hardware is hence not required as a board failure does notentail a switch over to a whole set of passive boards. In the BSC3000 the boards work:

Either in hot stand-by (active / passive) mode: OMU + private MMS, CEM, 8K SWT, IEM (in

an LSA). A single faulty board has no impact on the BSC. Multiple faults have also noimpact, providing that one board works in each pair of boards.

Or in parallel (both boards are simultaneously active): ATM SWT + ATM RM, shared MMS.

Or in N+P mode: TMU. The boards work in load sharing, processing active and passiveprocesses. P failures preserve nominal capacity.

The hardware and software architecture of the BSC3000 (one-to-one links between

hardware modules, supervision software, supervision activity of passive modules) allowprecise and immediate fault detection (both hardware and software failures).

7.6.1 REDUNDANCY IN THE CONTROL NODE

The fault tolerance algorithm implemented in the BSC Control Node allows fast faultrecovery, by reconfiguring the software activity on working modules, without impactingservice. The fault tolerance algorithm is implemented both on TMU and on OMU modules.See example below concerning the N+P redundancy of the TMUs.

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Fault tolerance example: swap on TMU failure

The figure below depicts the fault tolerance principle with a failure on a TMU. In thisexample, there are 3 groups of processes; each is composed for fault tolerance purposes of

1 active process Ai plus 1 passive process Pi where i is the application identifier.

The 3 active processes are distributed across 3 TMUs. The passive process related to oneactive process does not run on the same TMU as the active process, but on one of the other2 TMUs. The passive processes are directly and continuously updated by theircorresponding active process, at each occurrence of an event, like a communicationestablishment or release, handover... so that at each stable state, active and passive

processes have the same information on the traffic processing. If an active process fails(TMU hardware or software failure), the passive process can then take over without anyimpact on the service.

Figure 9: Fault tolerance with TMU failure

On failure of TMU1, the fault tolerance algorithm performs the activity-swap by electing thepassive A1 process as Active. The figure shows the new distribution of processing over the2 available TMUs.

On the OMU, the OA&M and supervision processes are secured by the fault tolerance

algorithm. However, the operating system level processes and the I/O processesare notsynchronized by this mechanism. When an OMU fails, those processes die without beingcontinued by the redundant OMU. Indeed, each OMU has its private disk for all system leveldata and at any time only the active OMU controls both disks containing the GSM applicationdata.

The ATM SWT are simultaneously active: the ATM communication goes through bothmodules, so that if a module fails, the message will go through the other one and get todestination. In normal operation, the destination module receiving both messages, willdiscard one.

7.6.2 REDUNDANCY IN THE INTERFACE NODE

In the Interface Node, all modules are 1+1 hot stand-by redundant. However the redundancyand defence mechanisms are slightly different between the CEM and the Resource Modules(RM).

The CEM are synchronised: the active CEM updates the passive one with all traffic and

OA&M related information. In case of active CEM failure, the RMs detect the link failure atthe hardware level and switches to the redundant CEM.

TMU#1

A1

P2

P3

TMU#2

A2

TMU#3

P1

A3

TMU#1

A1

P2

P3

TMU#2 TMU#3

P1

A3

A2

A1

P2

P3

TMU#1

A1

P2

P3

TMU#2

A2

TMU#3

P1

A3

TMU#1

A1

P2

P3

TMU#2 TMU#3

P1

A3

A2

A1

P2

P3

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7.6.3 RELIABILITY ANALYSIS

This section gives the results of the BSC3000 modules reliability analysis, in terms of MTBF

(Mean Time Between Failure). The results are given for each module of the Control Node,and the Interface Node and are computed for mature modules.

Module MTBF (hours) MTBF (years)

OMU 173943 20

TMU1 207814 24

TMU2 1112161 127

MMS1 (without disk) 703728 114

MMS2 (without disk) 1095000 125

CC1 230894 26

Control

Node

SIM 5263347 591

CEM 113880 13

8K 332880 38

ATM 551880 47

LSA (E1) with IEM1 357940 44

LSA ( T1) with IEM1 357940 44

LSA (E1) with IEM2 357940 44

LSA ( T1) with IEM2 357940 44

Interface

Node

SIM 5263347 591

Modules MTBF figures

7.7. LOAD BALANCING

The purpose of this function is to distribute processing in an optimal way over the TMUs andto use the BSCs resources optimally. It is performed by distributing the processing related tothe different cell groups (i.e. sets of cells belonging to the same process) equally over theTMUs. The whole processing relative to a cell group is executed on a single TMU. The

corresponding passive (or redundant) process is executed on another TMU.

The cell groups are determined at boot time according to data associated with the cells (Cell

Group Management function). When a BTS is added to the BSC, it is added to an old or anew cell group thanks to the same algorithm. When a cell or a TRX is added to a BTS, thecorresponding cell group has more load. In term of traffic per CG, the only limitation is thecapacity of the TMU.

The distribution of cell groups and redundant processes is done automatically by the systemat boot time as well.

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Load balancing allows a redistribution of the cell groups on the TMUs and is executed:

Automatically :

When a TMU module fails or comes into operation (for hardware or operatorreasons)

When the operator locks a TMU

Build-on-line (option from the OMC-R GUI) :

When cell groups are modified (to add BTSs)

When an imbalance of the TMU CPU loads is detected by the BSC. In this case,the load balancing can be done during non-busy hours.

In the system, the processor load of each TMU mainly depends on the number of

BTSs/cells/TRXs to manage, and the related amount of traffic. When there are modificationsto BTS configuration (addition of TRX) or BSC configuration (addition of TMU) the Load

Balancing service allows redistribution of processing with the best use of the BSCs

resources. The following chart gives an example of the use of Load Balancing when a TMUis added to the BSC.

Figure 10: Load balancing with a new TMU extension

The initial configuration of the BSC is 2 TMUs, and one more is added and provisioned fortraffic management. The BSC computes automatically a new distribution and applies it. The

re-distribution is achieved without exposure time by first adding new passive members to thegroups, then swapping their activity and finally suppressing the useless passive members.

Note that the two TMUs required to support SS7 signalling (in 1+1 redundancy scheme) arenot involved in the Load Balancing mechanism.

TMU#1

A1

A2

A3

P5

P4

P6

TMU#2

P1

P2

P3

A5

A4

A6

1. Initial configuration

TMU#1

A1

A2

A3

P5

P4

P6

TMU#2

P1

P2

P3

A5

A4

A6

2. Addition of one TMU

TMU#1

A1

A2 P5

P4

TMU#2

P2A5

3. Configuration after automatic load balancing between the three TMUs

TMU#3

P1

P3

A4

A6

TMU#3

P4

P6

P1

P3

P6 A3

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7.8. HARDWARE MANAGEMENT

7.8.1 GENERAL PRINCIPLES

The hardware modules of the BSC3000 are hot insert/extract. This means that a hardwaremodule can be replaced (repair) or added (capacity extension) in the equipment withoutshutting down even partly the machine and without any service impact.

Furthermore, the BSC3000 offers plug & play (or auto discovery) capability both forequipment start-up and for module hot insertion: the modules are automatically detected,started and configured. A simple operator command from OMC-R is then enough to put themodule in service.

All hardware modules (except SIMs, FANs and PCIU) of the BSC3000 are modelled andmanaged as logical objects. This allows both the BSC3000 and the OMC-R to provide to theoperator precise information and services on each individual hardware module:

Board representation on the OMC-R GUI: The physical BSC board layout will berepresented in the OMC-R GUI.

Fault representation: A hardware problem can be tracked thanks to this newrepresentation which allows faulty boards to be highlighted on the OMC-R GUI.

Private Datacollection: Dynamic data can be collected per boards to give to theoperator specific information related to the boards. (Localization, Firmware identification,Inventory information)

Preventive maintenance actions: preventive maintenance can be performed on theBSC3000 via regular checking of alarms, notifications or boards status informationavailable at the OMC-R.

The above features improve the operational effectiveness of the BSS network management.

7.8.2 HARDWARE STATE DETECTION

The BSC3000 hardware management from the OMC-R is based on the hardware statedetection capability of the BSC3000. The BSC3000 is able to detect its own hardwareconfiguration state at start-up or when a module is inserted/extracted, and report thisinformation to the OMC-R.

Start-up or module insertion

CN (Control Node) and IN (Interface Node) objects are automatically created when the user

creates the BSC object on the OMC-R. CN and IN platforms are created with their fullhardware configuration. Platforms will send notifications indicating the hardwareconfiguration state that was detected on the corresponding platform objects (CN, IN, LSA ortrans-coding equipment) :

disabled/not installed : the object is not present in the shelf

disabled/failed: the object is present in the shelf but is not operational due to a failure

enable/on-line : the object is present and operational

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This information is stored on the OMU disk and sent to the OMC. It can be read on the OMUdisk, even when a module is out of service. The information is also stored at OMC-R leveland can be displayed upon operator request.

Module extraction

A specific event is sent indicating a state change to disabled/{notInstalled} of the object thatwas previously in the slot. On reception of this state change, the OMC-R will modify thecolour of the corresponding logical object on the GUI.

7.8.3 PLUG & PLAY

The plug & play capability allows an easy & efficient maintenance of the BSC hardwareequipment. During equipment start-up and when a module is added to or removed from theequipment, the plug & play feature allows the BSC3000 to report automatically to the OMC-

R the information about the BSC hardware configuration.

The main steps of equipment cold start-up and hot restart and module hotinsertion/extraction are described below.

BSC cold start-up (MIB not built)

The operator builds the network at OMC-R level and creates the BSC logical object.

As soon as the OMC-R / BSC link is established, the BSC sends a notification indicatingthat a MIB build is requested

Upon receipt of this notification, the OMC-R operator triggers the MIB build phase. Thisphase ends with the creation of the MIB logical objects (included hardware objects)followed by the reception of a report build message.

The BSC sends a group of notifications giving to the OMC-R the description of thehardware objects detected state

The OMC-R updates automatically the physical hardware objects state and displaysthem on the HMIBSC hot restart (MIB already built)

Since the MIB is already built, only the hardware configuration consistency is checked. Itis checked that modules have not been introduced nor removed while the BSC wasswitched off. The BSC will have the same behaviour as in a cold start-up.

Module hot insertion

The module hot insertion may be described as:

Module insertion by the craft person

Hardware detection and BIST

Front panel LED state depending on BIST results

Verification by the craft person that the LED state is correct

Hardware state notification including BIST results sent towards the OMC-R

Module state updated at the OMC-R and displayed on the HMI

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Module hot extraction

When a module is extracted, a notification is sent to the OMC-R. This notification is a statechange to disabled, {notInstalled}. The module state is then updated at the HMI.

Note.

For OMU and MMS modules, a button needs to be pushed before extracting them. After a few

seconds, the path finding LED starts blinking. Those modules can then be safely extracted.

7.8.4 OBJECT MODEL AT OMC-R

bsc3Geqpt

cc

cn

mms omu tmu

mms

in

8k lsacem

iem

atm

Figure 11: Hardware object tree

New hardware objects are introduced into the OMC-R BSS Q3 object model for each type ofboard to manage in a BSC3000. These objects will be used by the different OMC-Rapplications (configuration, fault, performance), exactly like the other Q3 objects. Forexample, a fault related to a hardware module will be notified directly on the correspondinghardware object. These hardware objects will be made visible both in the internal Q3interface (MD/OMC-R) and in the external one (MD/NMS) as it can be seen in the following

figure.

If installed, the DS512 links are bound to the 8k-SRT object.

Note that the PEC codes of the boards installed in a BSC3000 can be obtained from the MMIof the OMC-R (via a Display command on the corresponding objects).

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7.8.5 LED DISPLAY

All BSC3000 modules have the same 2 LED's on the upper part of each modules front panelto ease on-site maintenance and reduce the risk of human error. The table below gives thedescription of the LED, the possible combinations and meaning.

Red Green Meaning

Not powered

Module diagnostics running (BIST)

Module is active

Module is passive (1)

Alarm state

Path finding (2)

: Unlighted LED : Winking LED

(1): indicates that a board does not have any active processes

(2): indicates that a board is flagged for replacement or for any other reason,

in order to avoid errors by the maintenance staff

7.9. SOFTWARE UPGRADE

7.9.1 SOFTWARE DELIVERY

For each version and edition, the complete BSS software is delivered on CD-ROM media (2CD-ROMs). This volume can be used at the OMC or TML level. It is sufficient for allupgrades from any authorized version (typically N-2 and N-1 versions).

7.9.2 BSC DOWNLOADING FROM THE OMC-R

The downloading of a new version or edition of software can be done remotely duringdaylight hours, without any operational impact. Only modified files in the new version aredownloaded.

Note: There is no PROM memory on BSC3000 hardware module, with the exception

of the ATM SWT module. All firmware is in flash EPROM and can be modified anddownloaded remotely by the system.

The complete BSS software (BSC, TCU and BTS) is downloaded from the OMC-R to theBSC.

Note: The OMC and BSC3000 are connected through Ethernet and IP protocol. Thethroughput is up to 10/100 Mbit/s if the OMC is locally connected to the BSC. Whenthe BSC is remote, a minimum throughput of 256 kbit/s is necessary for the efficiencyof OMC-BSC communication.

It is also possible to download the BSC software locally from the TML.

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7.9.3 UPGRADE EXECUTION

Before any upgrade procedure, the equipment must check its hardware (flash memory

checksum).

The execution of the upgrade is ordered by the OMC and controlled by the BSC (in the OMUmodule), after the complete transfer of new files. Only the modules that have modifiedsoftware are downloaded again.

There are 2 upgrade procedures:

1- On-line upgrade (no downtime) :

If, between the current SW version and the new SW version, theres no change in BSCdatabase (or MIB) format and no change to BSC internal SW interfaces, then the type 4upgrade mechanism shall be used.

This type 4 upgrade applies most often for patch or some edition upgrades (minorupgrade).

The principle is to sequentially upgrade each module, starting with the passive one and thenswact to the other. The passive module becomes active with the new SW, the activebecomes passive and is then upgraded with the new SW.

The main feature of this type 4 mechanism is that theres no BSC3000 downtime (samebehaviour as on the BSC 2G). More precisely, theres no impact on established calls notinvolved in a Hand-Over.

2 - Off-line upgrade (entails a BSC downt ime) :

When theres a change in BSC database (or MIB) format or a change on BSC internal SW

interfaces (between current and new SW versions) , then the type 6/7 upgrade mechanism

shall be used.

This type6/7 upgrade applies most often for version or some edition upgrades (major

upgrade).

The principle is to build on line the new MIB (only if theres a change in MIB format), andthen to re-start the BSC3000 with the new SW and the new MIB.

In this case, theres a global service downtime.

The following table provides a comparison between BSC 2G and BSC3000 upgrademechanisms :

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7.9.4 BTS S/W DOWNLOADING

In BSSV16.0, S/W downloading to the BTSs can either be done off-line (as in previousreleases) or on-line (background downloading). Depending on the BTS type/configuration

either one or both of those options are available.

BTS S/W background downloading allows minimising the service interruption.

7.9.5 TCU S/W DOWNLOADING

On-line upgrade with background downloading :

The TCU3000 SW upgrade is executed as a background activity.

The TCU3000 software is downloaded by the BSC3000 through a set of 4 LAPD

connections.The size of the full TCU software is approximately 13 Mo. It is compressed and divided intoseveral files (one set of files per module type : CEM, TRM, LSA), in order to download onlythe modified module software between two versions and to reduce as much as possible the

downloading duration.

The upgrade of TCU modules is done one by one, along with the software download.Theres no impact on the TCU operation except for each TRM module, which is restartedafter its software download (loss of on-going calls processed by this TRM). The unavailabilityof the TRM module (restart) lasts less than 2 minutes. In order to minimize the impact on on-going calls, theres a soft blocking procedure performed on the TRM before being upgraded:no new calls are set-up and on-going calls are maintained for 3 minutes (if not releasedbefore). At the end of the 3 minutes timer, the few remaining calls (if any) are released with

TRM reset.

Off-line upgrade:

From V16.0 onwards, off-line upgrades are performed as follows: the SW is downloaded bythe BSC3000 to the TCU3000 modules in background and is then activated along withTCU3000 start-up.

(The TCU software can also be installed locally from the TML as part of the commissioningprocedure (off-line installation)).

In this case, a global service interruption is incurred.

typical usage BSC 2G BSC3000

m nor upgra e :

type 4 mechanism : BSC chainswact

type 4 mechanism : sequentialmodule per module swact

no BSC 2G downtime no BSC3000 downtime

major upgrade :type 5 mechanism : on-line N+1database build, BSC passivechain SW update, BSC chainswact, BSC passive chain SWupdate

type 6/7 mechanism : on-lineN+1 database build (if required(type 6)), BSC e3 re-start withnew SW

no BSC database formatchange

patch, editionapplication

change in BSC databaseformat (and/or change in

modules SW interfaces forBSC e3 only)

version, edition (patch)upgrade

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7.10. HARDWARE UPGRADE

7.10.1 TMU EXTENSION

The BSC3000 capacity can be upgraded by adding 1 or more TMU modules in the ControlNode. Those modules can be hot-inserted in the equipment without any impact on theservice. The BSC3000 will take them into account and configure them automatically. Whenthe operator puts the new modules in service, the BSC3000 will distribute the call processingon those TMUs as well.

7.10.2 LSA EXTENSION

The BSC3000 connectivity can be increased by adding 1 or more LSA modules. Thosemodules are plug & play as well. However the operator has to configure and connect thenew PCM links.

7.11. UPGRADE OF A BSC 2G BY A BSC3000

A specific procedure allows replacing a BSC 2G by a BSC3000 while minimising as much aspossible the service downtime. This procedure is based on a dedicated tool Multi-sitereparenting, running on the OMC-R. This tools allows to reparent all the BTSs from theBSC2G to the BSC3000 in a single operation and without any impact on the service(example : to reparent 40 sites/ 88 cells/ Trx 219/ AdjcHO 747 takes approximately 4 hours).After the BTSs being created on the BSC3000, they are dis-connected from the BSC2G andre-connected to the BSC3000. One BSC3000 can replace several BSC 2Gs, by usingseveral times the same procedure. It is possible to replace the BSC only or the BSC and

TCU in a single step.

7.12. TML (LOCAL MAITENANCE TERMINAL)

7.12.1 EQUIPMENT AND INTERFACE

The TML hardware is a PC. It works under Windows and behaves like a web browser.

The TML may be connected to the BSC OMU or CEM module through Ethernet connections.The operator can plug into the active or passive modules, provided that the LED status is

correct. The TML can also be plugged into a hub that is hosted in the cabling area interfaceof the BSC3000.

The TML interface is independent from the BSC software evolutions. The TML applicationsoftware is hosted in the OMU and the CEM.

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7.12.2 TML FUNCTIONS

MIB access

The TML accesses the MIB for:

Commissioning data modification -SC number -MC-R link definit ion (IP, direct, through A interface) -CM trunks setup -physical location definition (name, floor)

Software and Hardware marking information consultationInstallation

The TML allows a first BSC installation to be performed. It allows the customizationparameters of the BSC (BSC number, IP address, PCM type, etc.) to be read and modified.

Tests / maintenanceThe configuration information on the different hardware modules can be read from the TML:board identification and states, software version, software & patch markers.

The TML allows a whole set of tests to be performed to check the integrity of the BSCconfiguration: check the proper functioning of a hardware module, check the communicationbetween two hardware modules, and perform loop-back testing (LAPD, PCM, etc.).

The TML also provides on-line equipment monitoring capabilities: software spies, traces,

notification decoding, dump decoding.

8. INTERFACES

8.1. ABIS, ATER, AGPRS AND A INTERFACES

The Abis, Ater, Agprs and A interfaces remain unchanged with the BSC3000 both forprotocols and physical links (PCM).

As for BSC 2G, different Abis configurations for BTS connections are possible: star, chainand loop configurations.

With BSC and TCU 2G, each TCU has only 1 PCM for Ater. The TCU3000 can have several

Ater PCMs, because of much higher capacity. Hence the defence mechanisms between theBSC3000 and TCU3000 for PCM failures are more elaborate.

With the BSC3000 & TCU3000, the Ater interface PCMs are dynamically allocated.

8.2. BSC3000 CLOCK SYNCHRONIZATION

The BSC3000 synchronizes itself on Ater PCM links. There can be from 3 to 6 synchronizing

PCM links defined by static configuration at the BSC start-up. Those PCMs are managed bythe second LSA in the lower shelf of the Interface Node (slots 4, 5 & 6). If the BSC3000

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cannot synchronize on those PCM, it switches to its internal clock provided by the CEMmodule. Each change of synchronising PCM induces a notification to the OMC-R.

In order to insure a proper synchronisation, the clock frequency accuracy of the equipment

providing timing to the BSC3000 should be +/- 20 PPM minimum (as per ITU-T G813) andthe clock frequency stability as per ITU-T G813 recommendation.

8.3. BSC3000 / OMC-R INTERFACE

Though the same OMC-R manages both BSC2G and BSC3000, the interface betweenBSC3000 and OMC-R is Ethernet TCP/IP instead of X25 as for BSC 2G. The Ethernet LANcan be 10 Mbit/s or 100 Mbit/s. When the BSC3000 is remote from the OMC-R, the BSC andOMC-R LANs must be interconnected through a network (X25, Frame relay, etc.) with a

minimum throughput of 256 kbit/s.

The BSC3000 offers an object oriented interface to the OMC-R, which is close to the Q3modelisation of the BSS hosted in the OMC-R database.

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9.2. SHIPMENT

The BSC/TCU3000 cabinet is shipped as follows:

For BSC/TCU main frame the modules are shipped in situ (parked position away from thebackplane) within the cabinet. For the SAI frame the modules and doors are not shipped in place. The doors are packaged with

the cabinet but the modules are shipped loose.

The main frame and the SAI frame are shipped horizontally on a wooden pallet which can be movedby means of a fork-lift truck.

Once the main frame is extracted from the package, 4 lifting rings are available at the top of the framefor hoisting purposes.

All the parts of the cabinet are assembled during the on-site installation.

9.3. INSTALLATION

9.3.1 ENVIRONMENTAL CONDITIONS

The BSC3000 is designed to operate in clean rooms. It can not be installed in anenvironment where the equipment is subject to conductive pollution or to dry non-conductivepollution which could become conductive due to expected condensation.

9.3.2 FLOOR

The BSC3000 must be anchored to the floor (no anchoring to the wall). The flooring can be

one of the following types:

Raised floor tiles and a under floor cable management system.

Bare concrete floor.The foot print of the BSC3000 cabinet with cosmetic panels is the following:

Width Depth Foot print

mm in. mm in. m2 in

2

960 37.8 600 23.6 0.576 893

The minimum floor resistance must be 1000 kg/m (1.42 lb/in).

9.3.3 CLEARANCE

In case of cable tray installed under the ceiling, a minimum clearance of 2.5m (98.4 in.) isrequired between the floor and the cable tray.

If the cable tray is located in the raised floor, a minimum clearance of 2.4 m (94.4 in.) isrequired between the floor and the ceiling.

The cabinets can be placed side by side or back to back.

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A minimum distance of 0.3 m (11.8 in.) is required between the cabinet side (hinge hand)and the wall.

An additional area must be provisioned for door opening and for operations on the

equipment (installation, commissioning, maintenance...). A distance of 750mm is neededbetween the cabinet front side and the opposite wall to allow access to the cabinet.

10. REGULATORY COMPLIANCE

10.1. ENVIRONMENTAL CONDITIONS

For climatic and thermal conditions, the BSC3000 is compliant to ETS 300 019-1.3, class3.2, i.e., 5 C to +45 C for the temperature and 5% to 90 % of relative air humidity, inoperating conditions. However, the starting of a BSC3000 can only be performed between+5C and +45C.

For storage conditions, the BSC3000 complies to ETS 300 019-1.1, class 1.2.For transport conditions, the product complies to ETS 300 019-1.2 class 2.2.

10.2. ELECTROMAGNETIC (EMC) AND ELECTROSTATICCONDI