UMTS CS Protocols and Signaling Analysis

Part 1 OverviewTable of Contents i.........................................................................................Chapter 1 Overview 1-1......................................................................................

1.1 Introduction 1-1.......................................................................................1.2 CSCN Interfaces and Protocols 1-1........................................................1.3 Brief Introduction to Interfaces 1-3..........................................................1.4 CSCN Protocol System 1-7.....................................................................

1.4.1 MSOFTX3000 Protocol System 1-7...............................................1.4.2 UMG8900 Protocol System 1-9......................................................1.4.3 HLR9820 Protocol System 1-9.......................................................

1.5 CSCN Protocol Types 1-10.......................................................................1.5.1 SS7 Signaling Protocols 1-10...........................................................1.5.2 BICC Protocol 1-12...........................................................................1.5.3 H.248 Protocol 1-12..........................................................................1.5.4 Nb UP and Iu UP Protocols 1-13......................................................

Part 2 Transport ProtocolsTable of Contents i.........................................................................................Chapter 1 Narrowband MTP 1-1........................................................................

1.1 MTP1 1-1................................................................................................1.2 MTP2 1-1................................................................................................1.3 MTP3 1-2................................................................................................

1.3.1 Functions 1-2..................................................................................1.3.2 Message Format 1-4.......................................................................1.3.3 Signaling Procedures 1-14...............................................................

Chapter 2 Broadband MTP 2-1..........................................................................2.1 Overview 2-1...........................................................................................2.2 MTP3b 2-2..............................................................................................

2.2.1 Introduction of MTP3b 2-2..............................................................2.2.2 MTP3b Message Structure 2-4.......................................................

2.3 SAAL 2-5.................................................................................................2.3.1 SAAL Function Structure 2-5..........................................................2.3.2 SSCOP 2-6.....................................................................................2.3.3 SSCF 2-11........................................................................................2.3.4 LM 2-13.............................................................................................

Chapter 3 SCTP 3-1...........................................................................................3.1 Overview 3-1...........................................................................................

3.1.1 SCTP Concept 3-1..........................................................................3.1.2 Terminology 3-1..............................................................................3.1.3 SCTP Functions 3-3.......................................................................

3.1.4 SCTP Implementation in CSCN 3-4...............................................3.2 SCTP Messages 3-4...............................................................................3.3 Message Procedures 3-5........................................................................

Chapter 4 M3UA 4-1...........................................................................................4.1 Overview 4-1...........................................................................................

4.1.1 Brief Introduction of SIGTRAN 4-1.................................................4.1.2 Introduction of M3UA 4-2................................................................4.1.3 Terminology 4-3..............................................................................4.1.4 M3UA Implementation in CSCN 4-11...............................................4.1.5 Work Modes of M3UA in CSCN 4-11...............................................

4.2 Message Structure 4-12............................................................................4.2.1 M3UA Message Format 4-12............................................................4.2.2 M3UA Messages 4-12......................................................................4.2.3 Message Example 4-14....................................................................

4.3 Message Procedures 4-15........................................................................Chapter 5 SCCP 5-1...........................................................................................

5.1 Overview 5-1...........................................................................................5.1.1 SCCP Functions 5-1.......................................................................5.1.2 SCCP Basic Services 5-1...............................................................5.1.3 SCCP Implementation in CSCN 5-2...............................................

5.2 Message Structure 5-3............................................................................5.2.1 SCCP Message Types 5-4.............................................................5.2.2 SCCP Message Parameters 5-6....................................................5.2.3 Examples of Parameter Formats and Codes 5-8...........................5.2.4 Format Components of SCCP Messages 5-12................................

Chapter 6 TCAP 6-1...........................................................................................6.1 Overview 6-1...........................................................................................6.2 Message Structure 6-3............................................................................

Chapter 7 RTP and RTCP 7-1............................................................................7.1 Brief Introduction 7-1...............................................................................7.2 RTP/RTCP Applications 7-1....................................................................7.3 Packet Format and Meaning 7-2.............................................................

7.3.1 RTP Header Format 7-2.................................................................7.3.2 RTCP Packet Format 7-3...............................................................7.3.3 RTCP Functions 7-4.......................................................................7.3.4 RTCP Transmission Interval 7-4.....................................................

Part 3 Application ProtocolsTable of Contents i.........................................................................................Chapter 1 RANAP and Iu UP 1-1.......................................................................

1.1 Overview 1-1...........................................................................................

1.1.1 Definition and Functions of Iu Interface 1-1....................................1.1.2 Protocol Structure for Iu-CS Interface 1-2......................................1.1.3 Protocol Implementation for Iu-CS Interface 1-3............................

1.2 Introduction of RANAP Protocol 1-3........................................................1.2.1 Structure of the RANAP Protocol Stack 1-3...................................1.2.2 Classification of RANAP Elementary Procedures 1-4....................1.2.3 Description of RANAP Elementary Procedures 1-7........................1.2.4 Typical Procedures 1-21...................................................................

1.3 Introduction of Iu UP Protocol 1-27...........................................................1.3.1 Functions 1-27..................................................................................1.3.2 Operational Modes 1-28...................................................................1.3.3 Transparent Mode (TrM) 1-29..........................................................1.3.4 Support Mode (SMpSDU: Support Mode for predefinedSDU size) 1-30..........................................................................................1.3.5 Elementary Procedures 1-34............................................................

Chapter 2 BSSAP 2-1.........................................................................................2.1 Overview 2-1...........................................................................................

2.1.1 Definition and Functions of the A Interface 2-1...............................2.1.2 BSSAP Implementation in MSOFTX3000 2-1................................2.1.3 Structure of the Protocol Stack 2-2.................................................

2.2 Introduction of BSSAP Protocol 2-3........................................................2.2.1 BSSAP Messages 2-3....................................................................2.2.2 Message Structure 2-4...................................................................2.2.3 BSSMAP Procedures 2-4...............................................................

Chapter 3 MAP 3-1.............................................................................................3.1 Overview 3-1...........................................................................................

3.1.1 Definition of the MAP Interfaces 3-1...............................................3.1.2 Functions of the MAP Interfaces 3-3..............................................3.1.3 MAP Implementation in CSCN 3-4.................................................3.1.4 Structure of the Protocol Stack 3-4.................................................

3.2 Introduction of MAP Protocol 3-5............................................................3.2.1 Message Structure 3-5...................................................................3.2.2 Operation Types 3-5.......................................................................

3.3 Signaling Procedures 3-8........................................................................Chapter 4 H.248/MEGACO 4-1..........................................................................

4.1 Overview 4-1...........................................................................................4.1.1 Definition and Functions of the Mc Interface 4-1............................4.1.2 H.248 Implementation in CSCN 4-1...............................................4.1.3 Structure of the Protocol Stack 4-2.................................................

4.2 Introduction of H.248 Protocol 4-3..........................................................4.2.1 Overview 4-3...................................................................................

4.2.2 Message Structure 4-6...................................................................4.3 Signaling Procedures 4-13........................................................................

Chapter 5 BICC 5-1............................................................................................5.1 Overview 5-1...........................................................................................

5.1.1 Definition and Functions of the Nc Interface 5-1.............................5.1.2 BICC Implementation in MSOFTX3000 5-1....................................5.1.3 Structure of the Protocol Stack 5-2.................................................

5.2 Introduction of BICC Protocol 5-3...........................................................5.2.1 Basic Concepts 5-3.........................................................................5.2.2 Message Structure 5-12...................................................................

5.3 Signaling Procedures 5-16........................................................................Chapter 6 BSSAP+ 6-1......................................................................................

6.1 Overview 6-1...........................................................................................6.1.1 Definition and Functions of the Interface 6-1..................................6.1.2 BSSAP+ Implementation in MSOFTX3000 6-1..............................6.1.3 Structure of the Protocol Stack 6-2.................................................6.1.4 Message Structure 6-2...................................................................

6.2 Signaling Procedures 6-3........................................................................Chapter 7 CAP 7-1.............................................................................................

7.1 Overview 7-1...........................................................................................7.1.1 Definition and Functions of the Interface 7-1..................................7.1.2 CAP Implementation in MSOFTX3000 7-1.....................................7.1.3 Structure of the Protocol Stack 7-2.................................................7.1.4 Message Structure 7-2...................................................................

7.2 CAP Operations 7-3................................................................................7.2.1 Call Related Operations 7-3...........................................................7.2.2 SMS Related Operations 7-8..........................................................

7.3 Basic Signaling Procedures 7-9..............................................................Chapter 8 ISUP 8-1............................................................................................

8.1 Overview 8-1...........................................................................................8.1.1 Definition and Functions of the Interface 8-1..................................8.1.1 ISUP Implementation in MSOFTX3000 8-2....................................8.1.2 Structure of the Protocol Stack 8-2.................................................

8.2 Message Structure 8-3............................................................................8.3 Signaling Procedures 8-8........................................................................

Chapter 9 Nb UP and IPBCP 9-1.......................................................................9.1 Overview 9-1...........................................................................................

9.1.1 Brief Introduction to the Nb Interface 9-1........................................9.1.2 Definition and Function of the Nb 9-1.............................................9.1.3 Protocol Structure 9-2.....................................................................

9.2 Introduction to the Nb UP 9-4..................................................................

9.2.1 Functions 9-5..................................................................................9.2.2 Operational Modes 9-5...................................................................9.2.3 Elementary Procedures 9-6............................................................

9.3 Introduction to the IPBCP 9-6.................................................................9.3.1 Functions 9-7..................................................................................9.3.2 Primitive and Message Structure 9-7..............................................9.3.3 Elementary Procedures 9-8............................................................

Part 4 Signaling ProceduresTable of Contents i.........................................................................................Chapter 1 MGW Registration Procedures 1-1....................................................

1.1 MGW Registration Procedure 1-1...........................................................1.2 MGW Deregistration Procedure 1-1........................................................

Chapter 2 Mobility Management 2-1..................................................................2.1 Overview 2-1...........................................................................................2.2 Location Management 2-1......................................................................

2.2.1 Basic Procedures 2-2.....................................................................2.2.2 Major Procedures 2-5.....................................................................

2.3 Handover 2-12..........................................................................................2.3.1 Overview 2-12...................................................................................2.3.2 Classification 2-12............................................................................2.3.3 Intra-UMTS Handover 2-14..............................................................2.3.4 Inter-System Handover 2-22.............................................................

2.4 Roaming Restriction 2-30..........................................................................Chapter 3 Security Management 3-1..................................................................

3.1 Overview 3-1...........................................................................................3.2 Authentication 3-1...................................................................................

3.2.1 GSM Authentication 3-1..................................................................3.2.2 UMTS Authentication 3-4................................................................3.2.3 Dual-Mode MS Authentication 3-7..................................................

3.3 Encryption 3-9.........................................................................................3.4 Integrity Protection 3-10............................................................................3.5 TMSI Reallocation 3-11.............................................................................

Chapter 4 Call Procedures 4-1...........................................................................4.1 Mobile Subscriber Calling Mobile Subscriber 4-1...................................

4.1.1 Call Model 4-1.................................................................................4.1.2 Diagram of Call Procedures 4-1.....................................................4.1.3 Calling Procedures (Early Assignment Procedures) 4-4................4.1.4 Called Procedures (Early Assignment Procedures) 4-5.................4.1.5 Disconnection Procedures 4-6........................................................

4.2 Mobile Subscriber Calling PSTN Subscriber 4-6....................................

4.2.1 Call Model 4-6.................................................................................4.2.2 Diagram of Call Procedures 4-7.....................................................4.2.3 Call Procedures 4-9........................................................................

4.3 PSTN Subscriber Calling Mobile Subscriber 4-11....................................4.4 Pre-paging 4-12........................................................................................4.5 Call Forwarding Services 4-13..................................................................

4.5.1 CFU 4-14..........................................................................................4.5.2 CFB 4-15..........................................................................................4.5.3 CFNRy 4-19......................................................................................4.5.4 CFNRc 4-22......................................................................................

Chapter 5 SMS Procedures 5-1.........................................................................5.1 Overview 5-1...........................................................................................5.2 Mobile Originated SMS 5-1.....................................................................5.3 Mobile Terminated SMS 5-2...................................................................5.4 SMS Alerting Procedures 5-3..................................................................

Chapter 6 IN Service Handling Procedures 6-1.................................................6.1 Pre-paid Service Handling Procedures 6-1.............................................

6.1.1 Mobile Pre-paid Subscriber Calling Ordinary WCDMASubscriber 6-1.........................................................................................6.1.2 PSTN or Ordinary WCDMA Subscriber Calling Pre-paidSubscriber 6-2.........................................................................................6.1.3 Pre-Paid Subscriber Calling Pre-paid Subscriber 6-3.....................6.1.4 Pre-paid Subscriber Calling Ordinary WCDMA Subscriberwith CFU to Pre-paid Subscriber 6-5.......................................................6.1.5 Recharge Procedure 6-6................................................................

6.2 Mobile Originated SMS Handling Procedure 6-7....................................6.3 Mobility Management Event Notification Handling Procedure 6-8..........

Chapter 7 Location Service Procedures 7-1.......................................................7.1 Overview 7-1...........................................................................................7.2 General LCS Architecture 7-1.................................................................7.3 General Network Location Procedures 7-3.............................................

7.3.1 Mobile Terminated Location Request 7-3.......................................7.3.2 Mobile Originated Location Request 7-5........................................7.3.3 Network Induced Location Request 7-7..........................................

Part 5 Signaling AnalysisTable of Contents i.........................................................................................Chapter 1 Analysis of Location Update Signaling 1-1........................................

1.1 Overview of Location Update Signaling 1-1............................................1.2 IMSI Attach 1-1.......................................................................................

1.2.1 IMSI Attach Procedure 1-1.............................................................1.2.2 Interface Tracing Example of IMSI Attach 1-2................................

1.2.3 Key Messages of IMSI Attach 1-3..................................................1.3 IMSI Detach 1-15......................................................................................

1.3.1 IMSI Detach Procedure 1-15............................................................1.3.2 Interface Tracing Example of IMSI Detach 1-16...............................1.3.3 Key Messages of IMSI Detach 1-16.................................................

1.4 Normal Updating 1-19...............................................................................1.4.1 Normal Updating Procedure 1-19.....................................................1.4.2 Interface Tracing Example of Normal Updating 1-19........................1.4.3 Main Tracing Messages of Normal Updating 1-20...........................1.4.4 Normal Updating Failure Procedure 1-30.........................................1.4.5 Interface Tracing Example of Normal Updating Failure 1-30............1.4.6 Main Tracing Messages of Normal Updating 1-30...........................

Chapter 2 Analysis of Relocation Signaling 2-1.................................................2.1 Overview of Relocation Signaling 2-1.....................................................

2.1.1 Relocation Procedure 2-1...............................................................2.1.2 Interface Tracing Example of Relocation 2-1..................................2.1.3 Key Messages of Relocation 2-2....................................................2.1.4 Relocation Failure Messages 2-6...................................................2.1.5 Interface Tracing Example of Relocation Failure 2-7......................2.1.6 Key Messages of Relocation Failure 2-7........................................

Chapter 3 Analysis of Call Signaling 3-1............................................................3.1 Intra-Office Calls 3-1...............................................................................

3.1.1 Intra-Office Call Procedure 3-1.......................................................3.1.2 Interface Tracing Example of Intra-Office Call 3-2..........................3.1.3 Key Messages of Intra-Office Call 3-2............................................3.1.4 Call Failure Procedure 3-21..............................................................3.1.5 Call Failure Messages Traced 3-22..................................................

Chapter 4 Analysis of Iu Interface Protocol 4-1..................................................4.1 Overview 4-1...........................................................................................4.2 Q.AAL2 Protocol Application 4-1.............................................................

4.2.1 The process of Normal Establishment 4-2......................................4.2.2 Establishment Failure 4-2...............................................................4.2.3 Normal Release 4-4........................................................................4.2.4 Example of Q.AAL2 Trace 4-5........................................................4.2.5 Examples of Important Messages of Q.AAL2 4-5...........................

4.3 Iu UP Application 4-9..............................................................................4.3.2 Major Functions of Iu UP 4-9..........................................................4.3.3 Example of lu UP Trace in Voice Call 4-10.......................................

4.4 Basic Signaling Procedure at Iu Interface 4-11.........................................4.4.2 Voice Call Establishment and Release 4-11.....................................4.4.3 VP Call Establishment and Release 4-12.........................................

4.4.4 Examples of Iu UP Important Messages 4-12..................................4.5 Case Analysis of Iu Interface Fault 4-14...................................................

4.5.1 Overview 4-14...................................................................................4.5.2 Unsuccessful Q.AAL2 Signaling Establishment 4-15.......................4.5.3 Unsuccessful Iu UP Initialization 4-17..............................................

Appendix A Abbreviations A-1............................................................................

HUAWEI

1. Overview

2. Transport Protocols

3. Application Protocols

4. Signaling Procedures

5. Signaling Analysis

HUAWEI UMTS Circuit-Switched Core Network Protocols and Signaling Analysis

V100R001

HUAWEI UMTS Circuit-Switched Core Network

Protocols and Signaling Analysis

Manual Version T2-030240-20041020-C-1.00

Product Version V100R001

BOM 31026440

Huawei Technologies Co., Ltd. provides customers with comprehensive technical support and service. Please feel free to contact our local office or company headquarters.

Huawei Technologies Co., Ltd.

Address: Administration Building, Huawei Technologies Co., Ltd.,

Bantian, Longgang District, Shenzhen, P. R. China

Postal Code: 518129

Website: http://www.huawei.com

Email: [email protected]

Copyright 2004 Huawei Technologies Co., Ltd.

All Rights Reserved

No part of this manual may be reproduced or transmitted in any form or by any means without prior written consent of Huawei Technologies Co., Ltd.

Trademarks

, HUAWEI, C&C08, EAST8000, HONET, , ViewPoint, INtess, ETS, DMC,

TELLIN, InfoLink, Netkey, Quidway, SYNLOCK, Radium, M900/M1800, TELESIGHT, Quidview, Musa, Airbridge, Tellwin, Inmedia, VRP, DOPRA, iTELLIN, HUAWEI OptiX, C&C08 iNET, NETENGINE, OptiX, iSite, U-SYS, iMUSE, OpenEye, Lansway, SmartAX, infoX, TopEng are trademarks of Huawei Technologies Co., Ltd.

All other trademarks mentioned in this manual are the property of their respective holders.

Notice

The information in this manual is subject to change without notice. Every effort has been made in the preparation of this manual to ensure accuracy of the contents, but all statements, information, and recommendations in this manual do not constitute the warranty of any kind, express or implied.

Summary of Updates

This section provides the update history of this manual and introduces the contents of subsequent updates.

Update History

This manual is updated for a major product version to maintain consistency with system hardware or software versions and to incorporate customer suggestions.

Manual Version Notes

T2-030240-20041020-C-1.00 Initial commercial release

Updates of Contents

None.

About This Manual

Release Notes

The manual applies to UMTS circuit-switched core network V100R001.

Organization

The manual focuses on functions, hierarchical architecture, and message structures of protocols and signaling processes in the UMTS circuit-switched core network.

There are five parts and an appendix in the manual.

z PART 1 Overview profiles the external interfaces and the running protocols of the interfaces in the UMTS circuit-switched core network.

z PART 2 Transport Protocols details the transport protocols used in the UMTS circuit-switched core network, including narrowband MTP, broadband MTP, SCTP, SIGTRAN, SCCP, TCAP, RTP, and RTCP.

z PART 3 Application Protocols focuses on the application protocols used in the UMTS circuit-switched core network, including H.248/MEGACO, ISUP, CAP, MAP, BSSAP, BSSAP+, RANAP, BICC, Iu UP, Nb UP, and IPBCP.

z PART 4 Signaling Procedures presents typical service procedures. z PART 5 Signaling Analysis describes the method of analyzing signaling

procedures through interface tracing, which is helpful for troubleshooting and handling.

z Appendix lists the acronyms and abbreviations used in the manual.

Intended Audience

The manual is intended for the following readers:

z Marketing technical specialists z Project engineering technicians z Operation and maintenance personnel

Conventions

The manual uses the following conventions:

I. General conventions

Convention Description

Arial Normal paragraphs are in Arial.

Arial Narrow Warnings, Cautions, Notes and Tips are in Arial Narrow.

Boldface Headings are in Boldface.

Courier New Terminal Display is in Courier New.

II. Symbols

Eye-catching symbols are also used in the manual to highlight the points worthy of special attention during the operation. They are defined as follows:

Caution Means reader be extremely careful during the operation.

Note Means a complementary description.

Feature Description HUAWEI UMTS Circuit-Switched Core Network Table of contents

i

Table of Contents

Part 1 Overview

Chapter 1 Overview....................................................................................................................... 1-1 1.1 Introduction ........................................................................................................................ 1-1 1.2 CSCN Interfaces and Protocols......................................................................................... 1-1 1.3 Brief Introduction to Interfaces........................................................................................... 1-3 1.4 CSCN Protocol System ..................................................................................................... 1-7

1.4.1 MSOFTX3000 Protocol System.............................................................................. 1-7 1.4.2 UMG8900 Protocol System..................................................................................... 1-9 1.4.3 HLR9820 Protocol System...................................................................................... 1-9

1.5 CSCN Protocol Types...................................................................................................... 1-10 1.5.1 SS7 Signaling Protocols........................................................................................ 1-10 1.5.2 BICC Protocol........................................................................................................ 1-12 1.5.3 H.248 Protocol ...................................................................................................... 1-12 1.5.4 Nb UP and Iu UP Protocols................................................................................... 1-13

Part 2 Transport Protocols

Chapter 1 Narrowband MTP ......................................................................................................... 1-1 1.1 MTP1 ................................................................................................................................. 1-1 1.2 MTP2 ................................................................................................................................. 1-1 1.3 MTP3 ................................................................................................................................. 1-2

1.3.1 Functions................................................................................................................. 1-2 1.3.2 Message Format ..................................................................................................... 1-4 1.3.3 Signaling Procedures ............................................................................................ 1-14

Chapter 2 Broadband MTP ........................................................................................................... 2-1 2.1 Overview ............................................................................................................................ 2-1 2.2 MTP3b ............................................................................................................................... 2-2

2.2.1 Introduction of MTP3b............................................................................................. 2-2 2.2.2 MTP3b Message Structure ..................................................................................... 2-4

2.3 SAAL.................................................................................................................................. 2-5 2.3.1 SAAL Function Structure......................................................................................... 2-5 2.3.2 SSCOP.................................................................................................................... 2-6 2.3.3 SSCF..................................................................................................................... 2-11 2.3.4 LM ......................................................................................................................... 2-13

Chapter 3 SCTP ............................................................................................................................. 3-1 3.1 Overview ............................................................................................................................ 3-1

3.1.1 SCTP Concept ........................................................................................................ 3-1 3.1.2 Terminology............................................................................................................. 3-1


ii

3.1.3 SCTP Functions ...................................................................................................... 3-3 3.1.4 SCTP Implementation in CSCN.............................................................................. 3-4

3.2 SCTP Messages................................................................................................................ 3-4 3.3 Message Procedures......................................................................................................... 3-5

Chapter 4 M3UA............................................................................................................................. 4-1 4.1 Overview ............................................................................................................................ 4-1

4.1.1 Brief Introduction of SIGTRAN................................................................................ 4-1 4.1.2 Introduction of M3UA .............................................................................................. 4-2 4.1.3 Terminology............................................................................................................. 4-3 4.1.4 M3UA Implementation in CSCN............................................................................ 4-11 4.1.5 Work Modes of M3UA in CSCN............................................................................ 4-11

4.2 Message Structure........................................................................................................... 4-12 4.2.1 M3UA Message Format ........................................................................................ 4-12 4.2.2 M3UA Messages................................................................................................... 4-12 4.2.3 Message Example................................................................................................. 4-14

4.3 Message Procedures....................................................................................................... 4-15

Chapter 5 SCCP............................................................................................................................. 5-1 5.1 Overview ............................................................................................................................ 5-1

5.1.1 SCCP Functions...................................................................................................... 5-1 5.1.2 SCCP Basic Services.............................................................................................. 5-1 5.1.3 SCCP Implementation in CSCN.............................................................................. 5-2

5.2 Message Structure............................................................................................................. 5-3 5.2.1 SCCP Message Types............................................................................................ 5-4 5.2.2 SCCP Message Parameters ................................................................................... 5-6 5.2.3 Examples of Parameter Formats and Codes.......................................................... 5-8 5.2.4 Format Components of SCCP Messages............................................................. 5-12

Chapter 6 TCAP ............................................................................................................................. 6-1 6.1 Overview ............................................................................................................................ 6-1 6.2 Message Structure............................................................................................................. 6-3

Chapter 7 RTP and RTCP ............................................................................................................. 7-1 7.1 Brief Introduction................................................................................................................ 7-1 7.2 RTP/RTCP Applications .................................................................................................... 7-1 7.3 Packet Format and Meaning.............................................................................................. 7-2

7.3.1 RTP Header Format................................................................................................ 7-2 7.3.2 RTCP Packet Format .............................................................................................. 7-3 7.3.3 RTCP Functions...................................................................................................... 7-4 7.3.4 RTCP Transmission Interval ................................................................................... 7-4

Part 3 Application Protocols

Chapter 1 RANAP and Iu UP ........................................................................................................ 1-1 1.1 Overview ............................................................................................................................ 1-1

1.1.1 Definition and Functions of Iu Interface .................................................................. 1-1


iii

1.1.2 Protocol Structure for Iu-CS Interface..................................................................... 1-2 1.1.3 Protocol Implementation for Iu-CS Interface........................................................... 1-3

1.2 Introduction of RANAP Protocol ........................................................................................ 1-3 1.2.1 Structure of the RANAP Protocol Stack.................................................................. 1-3 1.2.2 Classification of RANAP Elementary Procedures................................................... 1-4 1.2.3 Description of RANAP Elementary Procedures ...................................................... 1-7 1.2.4 Typical Procedures ............................................................................................... 1-21

1.3 Introduction of Iu UP Protocol.......................................................................................... 1-27 1.3.1 Functions............................................................................................................... 1-27 1.3.2 Operational Modes................................................................................................ 1-28 1.3.3 Transparent Mode (TrM) ....................................................................................... 1-29 1.3.4 Support Mode (SMpSDU: Support Mode for predefined SDU size) ..................... 1-30 1.3.5 Elementary Procedures......................................................................................... 1-34

Chapter 2 BSSAP........................................................................................................................... 2-1 2.1 Overview ............................................................................................................................ 2-1

2.1.1 Definition and Functions of the A Interface ............................................................. 2-1 2.1.2 BSSAP Implementation in MSOFTX3000............................................................... 2-1 2.1.3 Structure of the Protocol Stack ............................................................................... 2-2

2.2 Introduction of BSSAP Protocol......................................................................................... 2-3 2.2.1 BSSAP Messages................................................................................................... 2-3 2.2.2 Message Structure .................................................................................................. 2-4 2.2.3 BSSMAP Procedures.............................................................................................. 2-4

Chapter 3 MAP............................................................................................................................... 3-1 3.1 Overview ............................................................................................................................ 3-1

3.1.1 Definition of the MAP Interfaces.............................................................................. 3-1 3.1.2 Functions of the MAP Interfaces............................................................................. 3-3 3.1.3 MAP Implementation in CSCN................................................................................ 3-4 3.1.4 Structure of the Protocol Stack ............................................................................... 3-4

3.2 Introduction of MAP Protocol ............................................................................................. 3-5 3.2.1 Message Structure .................................................................................................. 3-5 3.2.2 Operation Types...................................................................................................... 3-5

3.3 Signaling Procedures......................................................................................................... 3-8

Chapter 4 H.248/MEGACO ............................................................................................................ 4-1 4.1 Overview ............................................................................................................................ 4-1

4.1.1 Definition and Functions of the Mc Interface........................................................... 4-1 4.1.2 H.248 Implementation in CSCN.............................................................................. 4-1 4.1.3 Structure of the Protocol Stack ............................................................................... 4-2

4.2 Introduction of H.248 Protocol ........................................................................................... 4-3 4.2.1 Overview ................................................................................................................. 4-3 4.2.2 Message Structure .................................................................................................. 4-6

4.3 Signaling Procedures....................................................................................................... 4-13


iv

Chapter 5 BICC .............................................................................................................................. 5-1 5.1 Overview ............................................................................................................................ 5-1

5.1.1 Definition and Functions of the Nc Interface ........................................................... 5-1 5.1.2 BICC Implementation in MSOFTX3000 .................................................................. 5-1 5.1.3 Structure of the Protocol Stack ............................................................................... 5-2

5.2 Introduction of BICC Protocol ............................................................................................ 5-3 5.2.1 Basic Concepts ....................................................................................................... 5-3 5.2.2 Message Structure ................................................................................................ 5-12

5.3 Signaling Procedures....................................................................................................... 5-16

Chapter 6 BSSAP+ ........................................................................................................................ 6-1 6.1 Overview ............................................................................................................................ 6-1

6.1.1 Definition and Functions of the Interface ................................................................ 6-1 6.1.2 BSSAP+ Implementation in MSOFTX3000............................................................. 6-1 6.1.3 Structure of the Protocol Stack ............................................................................... 6-2 6.1.4 Message Structure .................................................................................................. 6-2

6.2 Signaling Procedures......................................................................................................... 6-3

Chapter 7 CAP ............................................................................................................................... 7-1 7.1 Overview ............................................................................................................................ 7-1

7.1.1 Definition and Functions of the Interface ................................................................ 7-1 7.1.2 CAP Implementation in MSOFTX3000 ................................................................... 7-1 7.1.3 Structure of the Protocol Stack ............................................................................... 7-2 7.1.4 Message Structure .................................................................................................. 7-2

7.2 CAP Operations................................................................................................................. 7-3 7.2.1 Call Related Operations .......................................................................................... 7-3 7.2.2 SMS Related Operations ........................................................................................ 7-8

7.3 Basic Signaling Procedures............................................................................................... 7-9

Chapter 8 ISUP............................................................................................................................... 8-1 8.1 Overview ............................................................................................................................ 8-1

8.1.1 Definition and Functions of the Interface ................................................................ 8-1 8.1.1 ISUP Implementation in MSOFTX3000 .................................................................. 8-2 8.1.2 Structure of the Protocol Stack ............................................................................... 8-2

8.2 Message Structure............................................................................................................. 8-3 8.3 Signaling Procedures......................................................................................................... 8-8

Chapter 9 Nb UP and IPBCP......................................................................................................... 9-1 9.1 Overview ............................................................................................................................ 9-1

9.1.1 Brief Introduction to the Nb Interface ...................................................................... 9-1 9.1.2 Definition and Function of the Nb............................................................................ 9-1 9.1.3 Protocol Structure.................................................................................................... 9-2

9.2 Introduction to the Nb UP .................................................................................................. 9-4 9.2.1 Functions................................................................................................................. 9-5 9.2.2 Operational Modes.................................................................................................. 9-5


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9.2.3 Elementary Procedures........................................................................................... 9-6 9.3 Introduction to the IPBCP .................................................................................................. 9-6

9.3.1 Functions................................................................................................................. 9-7 9.3.2 Primitive and Message Structure ............................................................................ 9-7 9.3.3 Elementary Procedures........................................................................................... 9-8

Part 4 Signaling Procedures

Chapter 1 MGW Registration Procedures................................................................................... 1-1 1.1 MGW Registration Procedure............................................................................................ 1-1 1.2 MGW Deregistration Procedure......................................................................................... 1-1

Chapter 2 Mobility Management .................................................................................................. 2-1 2.1 Overview ............................................................................................................................ 2-1 2.2 Location Management ....................................................................................................... 2-1

2.2.1 Basic Procedures .................................................................................................... 2-2 2.2.2 Major Procedures.................................................................................................... 2-5

2.3 Handover ......................................................................................................................... 2-12 2.3.1 Overview ............................................................................................................... 2-12 2.3.2 Classification ......................................................................................................... 2-12 2.3.3 Intra-UMTS Handover ........................................................................................... 2-14 2.3.4 Inter-System Handover ......................................................................................... 2-22

2.4 Roaming Restriction ........................................................................................................ 2-30

Chapter 3 Security Management.................................................................................................. 3-1 3.1 Overview ............................................................................................................................ 3-1 3.2 Authentication .................................................................................................................... 3-1

3.2.1 GSM Authentication ................................................................................................ 3-1 3.2.2 UMTS Authentication .............................................................................................. 3-4 3.2.3 Dual-Mode MS Authentication ................................................................................ 3-7

3.3 Encryption .......................................................................................................................... 3-9 3.4 Integrity Protection........................................................................................................... 3-10 3.5 TMSI Reallocation............................................................................................................ 3-11

Chapter 4 Call Procedures ........................................................................................................... 4-1 4.1 Mobile Subscriber Calling Mobile Subscriber .................................................................... 4-1

4.1.1 Call Model ............................................................................................................... 4-1 4.1.2 Diagram of Call Procedures .................................................................................... 4-1 4.1.3 Calling Procedures (Early Assignment Procedures)............................................... 4-4 4.1.4 Called Procedures (Early Assignment Procedures)................................................ 4-5 4.1.5 Disconnection Procedures ...................................................................................... 4-6

4.2 Mobile Subscriber Calling PSTN Subscriber ..................................................................... 4-6 4.2.1 Call Model ............................................................................................................... 4-6 4.2.2 Diagram of Call Procedures .................................................................................... 4-7 4.2.3 Call Procedures....................................................................................................... 4-9

4.3 PSTN Subscriber Calling Mobile Subscriber ................................................................... 4-11


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4.4 Pre-paging ....................................................................................................................... 4-12 4.5 Call Forwarding Services................................................................................................. 4-13

4.5.1 CFU ....................................................................................................................... 4-14 4.5.2 CFB ....................................................................................................................... 4-15 4.5.3 CFNRy................................................................................................................... 4-19 4.5.4 CFNRc................................................................................................................... 4-22

Chapter 5 SMS Procedures .......................................................................................................... 5-1 5.1 Overview ............................................................................................................................ 5-1 5.2 Mobile Originated SMS...................................................................................................... 5-1 5.3 Mobile Terminated SMS .................................................................................................... 5-2 5.4 SMS Alerting Procedures .................................................................................................. 5-3

Chapter 6 IN Service Handling Procedures ................................................................................ 6-1 6.1 Pre-paid Service Handling Procedures ............................................................................. 6-1

6.1.1 Mobile Pre-paid Subscriber Calling Ordinary WCDMA Subscriber ........................ 6-1 6.1.2 PSTN or Ordinary WCDMA Subscriber Calling Pre-paid Subscriber ..................... 6-2 6.1.3 Pre-Paid Subscriber Calling Pre-paid Subscriber ................................................... 6-3 6.1.4 Pre-paid Subscriber Calling Ordinary WCDMA Subscriber with CFU to Pre-paid Subscriber ........................................................................................................................ 6-5 6.1.5 Recharge Procedure ............................................................................................... 6-6

6.2 Mobile Originated SMS Handling Procedure..................................................................... 6-7 6.3 Mobility Management Event Notification Handling Procedure .......................................... 6-8

Chapter 7 Location Service Procedures ..................................................................................... 7-1 7.1 Overview ............................................................................................................................ 7-1 7.2 General LCS Architecture.................................................................................................. 7-1 7.3 General Network Location Procedures.............................................................................. 7-3

7.3.1 Mobile Terminated Location Request ..................................................................... 7-3 7.3.2 Mobile Originated Location Request ....................................................................... 7-5 7.3.3 Network Induced Location Request ........................................................................ 7-7

Part 5 Signaling Analysis

Chapter 1 Analysis of Location Update Signaling ..................................................................... 1-1 1.1 Overview of Location Update Signaling............................................................................. 1-1 1.2 IMSI Attach ........................................................................................................................ 1-1

1.2.1 IMSI Attach Procedure ............................................................................................ 1-1 1.2.2 Interface Tracing Example of IMSI Attach .............................................................. 1-2 1.2.3 Key Messages of IMSI Attach ................................................................................. 1-3

1.3 IMSI Detach ..................................................................................................................... 1-15 1.3.1 IMSI Detach Procedure......................................................................................... 1-15 1.3.2 Interface Tracing Example of IMSI Detach ........................................................... 1-16 1.3.3 Key Messages of IMSI Detach.............................................................................. 1-16

1.4 Normal Updating.............................................................................................................. 1-19 1.4.1 Normal Updating Procedure.................................................................................. 1-19


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1.4.2 Interface Tracing Example of Normal Updating .................................................... 1-19 1.4.3 Main Tracing Messages of Normal Updating........................................................ 1-20 1.4.4 Normal Updating Failure Procedure...................................................................... 1-30 1.4.5 Interface Tracing Example of Normal Updating Failure........................................ 1-30 1.4.6 Main Tracing Messages of Normal Updating........................................................ 1-30

Chapter 2 Analysis of Relocation Signaling............................................................................... 2-1 2.1 Overview of Relocation Signaling...................................................................................... 2-1

2.1.1 Relocation Procedure.............................................................................................. 2-1 2.1.2 Interface Tracing Example of Relocation ................................................................ 2-1 2.1.3 Key Messages of Relocation................................................................................... 2-2 2.1.4 Relocation Failure Messages.................................................................................. 2-6 2.1.5 Interface Tracing Example of Relocation Failure .................................................... 2-7 2.1.6 Key Messages of Relocation Failure ...................................................................... 2-7

Chapter 3 Analysis of Call Signaling........................................................................................... 3-1 3.1 Intra-Office Calls ................................................................................................................ 3-1

3.1.1 Intra-Office Call Procedure...................................................................................... 3-1 3.1.2 Interface Tracing Example of Intra-Office Call ........................................................ 3-2 3.1.3 Key Messages of Intra-Office Call........................................................................... 3-2 3.1.4 Call Failure Procedure .......................................................................................... 3-21 3.1.5 Call Failure Messages Traced .............................................................................. 3-22

Chapter 4 Analysis of Iu Interface Protocol................................................................................ 4-1 4.1 Overview ............................................................................................................................ 4-1 4.2 Q.AAL2 Protocol Application ............................................................................................. 4-1

4.2.1 The process of Normal Establishment .................................................................... 4-2 4.2.2 Establishment Failure.............................................................................................. 4-2 4.2.3 Normal Release....................................................................................................... 4-4 4.2.4 Example of Q.AAL2 Trace ...................................................................................... 4-5 4.2.5 Examples of Important Messages of Q.AAL2 ......................................................... 4-5

4.3 Iu UP Application ............................................................................................................... 4-9 4.3.2 Major Functions of Iu UP......................................................................................... 4-9 4.3.3 Example of lu UP Trace in Voice Call ................................................................... 4-10

4.4 Basic Signaling Procedure at Iu Interface ....................................................................... 4-11 4.4.2 Voice Call Establishment and Release ................................................................. 4-11 4.4.3 VP Call Establishment and Release ..................................................................... 4-12 4.4.4 Examples of Iu UP Important Messages............................................................... 4-12

4.5 Case Analysis of Iu Interface Fault .................................................................................. 4-14 4.5.1 Overview ............................................................................................................... 4-14 4.5.2 Unsuccessful Q.AAL2 Signaling Establishment.................................................... 4-15 4.5.3 Unsuccessful Iu UP Initialization........................................................................... 4-17

HUAWEI

UMTS Circuit-Switched Core Network Protocols and Signaling Analysis

Part 1 Overview

Protocols and Signaling Analysis HUAWEI UMTS Circuit-Switched Core Network Table of Contents

i

Table of Contents

Chapter 1 Overview....................................................................................................................... 1-1 1.1 Introduction ........................................................................................................................ 1-1 1.2 CSCN Interfaces and Protocols......................................................................................... 1-1 1.3 Brief Introduction to Interfaces........................................................................................... 1-3 1.4 CSCN Protocol System ..................................................................................................... 1-7

1.4.1 MSOFTX3000 Protocol System.............................................................................. 1-7 1.4.2 UMG8900 Protocol System..................................................................................... 1-9 1.4.3 HLR9820 Protocol System...................................................................................... 1-9

1.5 CSCN Protocol Types...................................................................................................... 1-10 1.5.1 SS7 Signaling Protocols........................................................................................ 1-10 1.5.2 BICC Protocol........................................................................................................ 1-12 1.5.3 H.248 Protocol....................................................................................................... 1-12 1.5.4 Nb UP and Iu UP Protocols................................................................................... 1-13

Protocols and Signaling Analysis HUAWEI UMTS Circuit-Switched Core Network Chapter 1 Overview

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Chapter 1 Overview

1.1 Introduction

The universal mobile telecommunications system (UMTS) is distributed into separate physical entities. These entities must cooperate with each other to implement a task, and the devices and subsystems must be interconnected through various interfaces according to the specified protocols.

In the UMTS, signaling refers to the information required by different entities. A signaling system directs entities to cooperate with each other. What embody the signaling messages are interface and protocols:

z An interface represents the connection point between two adjacent network entities.

z A protocol defines the rules for information exchange on interfaces.

Protocols are hierarchical. In general, the application layer protocol is used to describe the protocol over an interface.

This chapter gives a general introduction of the interface types and protocols applying to variors interface of the circuit switched core network (CSCN), including:

z CSCN Interfaces and Protocols z Brief Introduction to Interfaces z CSCN Protocol System z CSCN Protocol System

1.2 CSCN Interfaces and Protocols

The equipment of Huawei WCDMA CSCN involves:

z (G) Mobile switching center (MSC) Server z Media gateway z Home Location Register

MSC Server and MGW can be integrated as an MSC.

As open network entities, the above equipment and external interfaces must adopt open protocols. Figure 1-1 shows the external interfaces and protocols of various CS entities.


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MSC Server

SCP HLR

MGW

GMLC

SMC C/D

Mc

(G)MSC Server

MGW

Mc

Nc/E

Nb

BSC

RNC

A

Iu-CS

C

PSTN

SG

TUP/ISUP

SIGTRAN

CAP/L

Lg

E

CS

SGSNGs

BSC: Base Station Controller CAP: CAMEL Application Part HLR: Home Location Register GMLC: Gateway Mobile Location Cente MGW: Media Gateway RNC: Radio Network Controller SGSN: Serving GPRS Support Node SIGTRAN: Signaling Transport SMC: Short Massgae Center SCP: Service Control Point SG: Signaling Gateway PSTN: Public Switched Telephone

Network

Figure 1-1 CNCS interface

Table 1-1 lists the external interfaces and protocols of various CS network entities.

Table 1-1 Interfaces and protocol of CS network entities

Interconnected entities Interface Signaling and protocols

MSCRNC Iu-CS RANAP, Iu UP

MSCBSC A BSSAP

MSC ServerVLR B Internal protocol

MSC ServerHLR C MAP

VLRHLR D MAP

MSC ServerMGW Mc H.248

MSC ServerMSC Server Nc, E BICC/ISUP, MAP

MSCMSC MSC ServerSMC

E MAP

VLRVLR G MAP

MSC ServerGMLC Lg MAP

SSPSCP CAP, L CAP, MAP

MSCPSTN MSCPLMN

- ISUP/TUP


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Interconnected entities Interface Signaling and protocols

MSC ServerSGSN Gs BSSAP+

MSC ServerSG - SIGTRAN

HLRAuC H Internal protocol

HLRSCP

HLRSGSN

MGWMGW Nb Nb UP

Note: The interface and the protocol adopted between the physical entities have no one-to-one relationship. z One protocol may be adopted over several different interfaces. For instance, the Mobile Application Part (MAP) protocol is adopted on the C, D, E, G, Lg, and L interfaces. z Several interfaces may exist between two entities while different protocols are adopted for each

interface. For instance, both Nc and E interfaces are defined between two MSC Servers, where the Bearer Independent Call Control (BICC) protocol is adopted for the Nc interface and the MAP protocol for the E interface.

1.3 Brief Introduction to Interfaces

I. Iu-CS Interface

Iu-CS interface refers to the interface between the CS and the UMTS terrestial radio access network (UTRAN) in the WCDMA network. It is embodied as the interface between the MSC and the RNC. It comprises:

z Control panel (CP)

The interface between the MSC Server and the RNC, also called lu CP.

z User panel (UP)

The interface between the MGW and the RNC, also celled lu UP.

Iu-CS interface adopts the Radio Access Network Application Part (RANAP) as the protocol of the lu CP, which is used to send the following information:

z UTRAN management z Call handling z Mobility management


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Iu-CS interface adopts the Iu UP protocol to bear and transmit the traffic.

II. A Interface

A interface refers to the interface between the cicuit switched (CS) domain of the GSM network subsystem (NSS) and the base station subsystem (BSS). It is embodied as the interface between the MSC and the BSC.

A interface adopts the Base Station Subsystem Application Part (BSSAP) protocol in the SS7 signaling system. It comprises voice channel and signaling channel. It is used to pass the following information:

z Mobile station (MS) management z Base transceiver station (BTS) management z Mobility management z Call handling

III. B Interface

B interface refers to the interface between the MSC Server and the VLR. It has no specific regulation on the signaling mode. It adopts the internal protocols. Through it:

z MSC Server obtains user informaton from VLR. z When a MS implements the location update, MSC Server notifies VLR to record

the location information. z When a MS activates a specific supplementary service or modifies related

service data, MSC Server notifies HLR to update the data through VLR.

IV. C Interface

C interface refers to the interface between the MSC Server and HLR. It adopts the MAP protocol in the SS7 signaling system. Its functions include:

z When a MS is called, HLR sends routing information to MSC Server. z It is used to pass short messages. z For CAMEL application, it is used to obtain the rouging information, user status,

and subscriptioin information when a MS is called.

V. D Interface

D interface refers to the interface between the VLR and the HLR. It adopts the MAP protocol in the SS7 signaling system. It is used to pass the following information.

z Authentication data z Location update information z User data in call setup z Supplementary data z VLR restoration information


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For CAMEL application, it is used to pass CAMEL user data and provide the mobile station roaming number (MSRN) to the public land mobile network (PLMN) visited.

VI. E Interface

E interface refers to the MAP interface between the MSC Server and the (G) MSC Server or the interface between the MSC Server and SMC. It adopts the MAP protocol in the SS7 signaling system. It is used to pass the following information:

z Switchover information z Short messages z Call control after inter-MSC switchover

VII. F Interface

F interface refers to the interface between the MSC Server and the equipment identity register (EIR). It adopts the MAP protocol in the SS7 signaling system.

When the MSC Server needs to check the validity of the international mobile station equipment identity (IMEI), it must exchange information related to the IMEI with the EIR through F interface.

VIII. G Interface

G interface refers to the interface between the VLRs. It adopts the MAP protocol in the SS7 signaling system. It is used to pass the following information:

z Location update data

When a MS roams to a new VLR, it obtains the IMSI from the former VLR.

z Authentication data

The authentication parameter is sent from the former VLR to the current one.

Because the MSC Server and the VLR are integrated, G and E interfaces are combined as E interface.

IX. Lg Interface

Lg interface refers to the interface between the MSC Server and the GMLC. It is used to support the location service (LCS). It adopts the MAP protocol in the SS7 signaling system. Through it:

z GMLC originates a location request of a destination user to the current MSC Server.

z MSC Server returns a result. z MSC Server reports the location inforamtion of the destination user to GMLC.


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X. L Interface

L interface refers to the MAP interface between the SSP and the SCP. It adopts the MAP protocol in the SS7 signaling system. It is used to report the invoke notification of the supplementary service.

Note: The aboveC, D, E, F, G, Lg, and L interfaces all adopt the MAP prototocl. Sometimes, all these interfaces are called MAP interfaces.

XI. Gs Interface

Gs interface refers to the interface between the MSC Server and the SGSN. It adopts the base station system application part+ (BSSAP+) protocol in the SS7 signaling protocol. Its functions include:

z SGSN sends MS location information to MSC Server. z SGSN receives paging information from MSC Server. z MSC Server announces that the MS is implementing the service handled by

MSC Server.

XII. H Interface

H interface refers to the interface between the HLR and the AuC. It has no specific regulation on the signaling mode. It is used to pass the user authentication and encryption data.

XIII. Mc Interface

Mc interface refers to the interface between the MSC Server and the MGW. It adopts the H.248 protocol. Throug it:

z During call handling process, MSC Server controls static and dynamic resources (including terminal properties, terminal connection relation, and media stream) of various transmission modes (IP/ATM/TDM).

z MSC Server sends status maintenance and management information to the MGW.

XIV. Nc Interface

Nc interface refers to the interface between the MSC Servers. It adopts the bearer independent call controller protocol (BICC). It provides inter-MSC call control ability


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independent of the UP bearer technology and CP signaling transmission technology for the UMTS narrowband CS domain service.

XV. Nb Interface

Nb interface refers to the interface between the MGWs. It is used to bearer control and transmission. The transmission mode of the user data can be RTP/UDP/IP or AAL2.

XVI. CAP Interface

CAMEL application part (CAP) interface refers to the interface between the SSP and the SCP, between the HLR and SCP. It adopts the CAP protocol in the SS7 signaling system. It is used to realize the signaling exchange between functional entities (SSP, IP, and SCP) of the intelligent network, thus supporting CAMEL services.

XVII. ISUP/TUP Interface

When the MSOFTX3000 functions as the GMSC Server, it provides the interface for the fixed network switching equipment or other mobile network equipment, and controls incoming/outgoing calls through the integrated services digital network user part (ISUP) or the telephone user part (TUP) of the SS7 signaling system.

XVIII. MSC Server and SG Interface

In the UMTS network, this interface is used to pass the switched circuit network (SCN) signaling through the IP network. It adopts the SIGTRAN protocol stack.

1.4 CSCN Protocol System

Huawei CSCN products includs:

z MSC Server (MSOFTX3000) z MGW (UMG8900) z HLR (HLR9820)

Their protocol development complies with the standard protocol specification.

1.4.1 MSOFTX3000 Protocol System

From the view of different protocol functions, MSOFTX3000 protocol system includes:

z SS7 application protocols

ISUP

MAP

CAP


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Radio access network application part (RANAP)

BSSAP

BSSAP+ z BICC protocols z H.248 protocols

The overall architecture of MSOFTX3000 protocol system is illustrated in Figure 1-2.

SCCPTCAP

ISUP

RANAP

BSSAP+

MAP

CAP

SCTP

IP

MAC

MTP3

MTP2

MTP1

MTP3b

SSCF-NNI

SSCOP

ATM

BICC H.248

M3UA

1

2

3

4

5

6

7

OSIlayers

TDM based IP based ATM based

ApplicationProtocols

TransportProtocols

BSSAP

SCCPTCAP

ISUP

RANAP

BSSAP+

MAP

CAP

SCTP

IP

MAC

MTP3

MTP2

MTP1

MTP3b

SSCF-NNI

SSCOP

ATM

BICC H.248

M3UA

1

2

3

4

5

6

7

OSIlayers


ApplicationProtocols

TransportProtocols

BSSAP

Figure 1-2 MSOFTX3000 protocol system

MSOFTX3000 protocol system is hierarchical. For the hierarchical structure of each protocol, Open Systems Interconnection (OSI) can be referenced except that some of the seven OSI layers are combined.

MSOFTX3000 signaling and protocols can be carried through a variety of transport media. For instance, the BICC protocol messages can be conveyed in the following four manners:

z TDM based MTP transmission z IP based SIGTRAN (M3UA/SCTP) transmission z SCTP transmission z ATM based MTP3b transmission

One transport protocol can provide transmission service for multiple application protocol systems.

For convenient description and understanding, MSOFTX3000 protocol system is divided into:

z Application protocols z Transport protocols


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I. Application Protocols

The application protocols are at the top of the protocol stack, implementing the information interaction function on the interfaces between the communication entities. The application protocols use the service provided by the transport protocols at the lower layers.

II. Transport Protocols

The transport protocols refer to all the lower-layer protocols below the application protocols. (The transport protocola mentioned here are protocol stack). They provide message transmission service for the application protocols according to the application protocols requirements.

1.4.2 UMG8900 Protocol System

UMG8900 protocol system includes:

z Media gateway control protocol (H.248) z Protocols over ATM z Protocols over IP z SIGTRAN protocol (based on the signaling gateway function embedded in the

UMG8900)

Figure 1-3 shows the general structure of UMG8900 protocols.

Iu UP

AAL2 SARSSCS

Q.AAL2

MTP-3bSAALAAL2

ATM

STCM3UA

IP

SCTP UDP

H.248

RTP RTCP

Nb UP

ATM-based IP-based

Figure 1-3 UMG8900 protocol system

1.4.3 HLR9820 Protocol System

In CSCN application, HLR9820 protocol system includes the MAP protocol in the SS7 signaling system. It is based on TDM, IP, or ATM, as shown in Figure 1-4.


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MAP

SCCP

SCTP

IP

MAC

MTP3

MTP2

MTP1

MTP3b

SSCF-NNI

SSCOP

ATM

TDM-based

Applicationparts

Message Transfer

Part

M3UA

TCAP

IP-based ATM-based

Figure 1-4 HLR9820 protocol system

1.5 CSCN Protocol Types

Based on the above analysis, the CS product protocols can be divided into:

z SS7 signaling protocols

Apply to MSOFTX3000 and HLR9820, based on TDM, IP, and ATM.

The user part includes TUP/ISUP, MAP, CAP, and BSSAP.

z BICC protocol

Applies to MSOFTX3000 only, based on IP.

z H.248 protocol

Applies to MSOFTX3000 and UMG8900, based on IP.

z Nb UP and Iu UP protocols

Applies to UMG8900 only, Nb UP protocol based on IP and ATM, and Iu UP protocol based on ATM.

1.5.1 SS7 Signaling Protocols

In CSCN, the SS7 application protocols are used on multiple interfaces.

For instance, the RANAP protocol is used on the Iu-CS interface, and BSSAP used on the A interface.


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The SS7 has a 4-layer structure. In view of its functions, the SS7 is divided into User Part and Message Transfer Part. See Figure 1-5.

SCCP

TCAP

ISUP

RANAP

BSSAP+

MAP

CAP

SCTP

IP

MAC

MTP3

MTP2

MTP1

MTP3b

SSCF-NNI

SSCOP

ATM


Application Parts

Message Transfer Part

BSSAP

M3UA

SCCP

TCAP

ISUP

RANAP

BSSAP+

MAP

CAP

SCTP

IP

MAC

MTP3

MTP2

MTP1

MTP3b

SSCF-NNI

SSCOP

ATM


Application Parts

Message Transfer Part

BSSAP

M3UA

Figure 1-5 SS7 signaling protocol

I. MTP Protocol

Message Transfer Part (MTP) protocol enables reliable transport of signaling messages between user functions. MSOFTX3000 provides three approaches for SS7 signaling transport:

z Over narrowband TDM transport network

The Signaling Gateway (SG) built in MSOFTX3000 provides the TDM interface for direct interconnection with the SCN signaling device.

z Over broadband IP network in SS7 MTP3-User Adaptation Layer (M3UA) protocol of SIGTRAN

Applies to MSOFTX3000 interworking with the SCN by means of independent SG.

z Over ATM through Message Transfer Part (broadband) (MTP3b)

Applies to the interface between MSOFTX3000 and Radio Access Network (RAN), namely, the Iu-CS interface, for the purpose of provisioning RANAP message transmission service.

II. User Part Protocol

UP protocol is the functional entity that uses the MTP capability. It is resident at the top of the SS7 and is used to achieve a variety of services and applications. The SS7 UP protocol is composed of several independent user protocols, including:


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z ISUP z MAP z CAP z RANAP z BSSAP z BSSAP+

1.5.2 BICC Protocol

The BICC protocol applies to the Nc interface of the UMTS network for interworking between the MSC Servers. As one of the application layer control protocols, it is used to establish, modify, and terminate calls. It can bear comprehensive PLMN/PSTN/ISDN services.

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