中国联通ims接口规范第一分册： mgw media gateway 媒体网关 mrfc multimedia resource...

QB/CU 193-2007

2007-10-31 发布 2007-10-31 实施

中国联通公司发布

中国联通 IMS 接口规范

第一分册：

Mw/Mg/Mi/Mj/Mk/Gm 接口

China Unicom IMS Interface Technical Specification（Part One）

Mw/Mg/Mi/Mj/Mk/Gm Interface

（V1.0）

中国联通公司企业标准

中国联通 IMS 接口规范第一分册：Mw/Mg/Mi/Mj/Mk/Gm 接口

I

目次

目次 .............................................................................. I 前言 ............................................................................ III 中国联通 IMS 接口规范第一分册：....................................................... 1 MwMgMiMjMkGm 接口 ................................................................. 1 1 范围 ................................................................................ 1 2 规范性引用文件 ...................................................................... 1 3 缩略语 .............................................................................. 2 4 概述 ................................................................................ 3 4.1 IMS 网络架构....................................................................... 3 4.2 定义 .............................................................................. 3 5 M 系列接口的协议 .................................................................... 4 6 接口相关消息和参数的传送 ............................................................ 4 6.1 Mg 接口 ........................................................................... 4 6.1.1 概述 ............................................................................ 4 6.1.2 初始呼叫 ........................................................................ 4 6.1.3 呼叫释放 ....................................................................... 15 6.2 Mi 接口........................................................................... 16 6.2.1 概述 ........................................................................... 16 6.2.2 会话初始化事务的处理 ........................................................... 17 6.2.3 S-CSCF 选择 BGCF .............................................................. 17 6.2.4 PSTN 终结呼叫流程（包括资源预留） .............................................. 18 6.2.5 CS 被叫流程 .................................................................... 21 6.3 Mj 接口........................................................................... 22 6.3.1 概述： ......................................................................... 22 6.3.2 电路交换网被叫流程 ............................................................. 22 6.4 Mk 接口 .......................................................................... 25 6.4.1 概述 ........................................................................... 25 6.4.2 接口流程 ....................................................................... 26 6.5 Mw 接口.......................................................................... 29 6.5.1 注册消息 ....................................................................... 29 6.5.2 会话消息 ....................................................................... 51 6.5.3 会话释放 ...................................................................... 136 6.6 Gm 接口 ......................................................................... 138 6.6.1 概述 .......................................................................... 138 6.6.2 注册/注销...................................................................... 139 6.6.3 会话管理 ...................................................................... 147 6.6.4 安全 .......................................................................... 150 6.6.5 信令压缩 ...................................................................... 151 附录 A （规范性附录） M 系列接口支持的消息....................................... 152

中国联通 IMS 接口规范第一分册：Mw(dd/ff)/Mg(17)/Mi(9)/Mj(49)/Mk(5)/Gm(hh)接口

II

附录 B （规范性附录） M 系列接口支持的消息头..................................... 152 B.1 基本的消息头 .................................................................... 153 B.2 路由相关的消息头 ................................................................ 153 B.3 私有 SIP 消息头（P-header） ....................................................... 154


III

前言

本标准是中国联通IMS接口规范的一部分，该IMS接口规范的名称与结构如下：

1. 《中国联通 IMS 网络技术体制研究报告》 2. 《中国联通 IMS 设备规范第一分册：会话控制类设备》 3. 《中国联通 IMS 设备测试规范第一分册：会话控制类设备》 4. 《中国联通 IMS 设备规范第二分册：用户数据管理类设备》 5. 《中国联通 IMS 设备测试规范第二分册：用户数据管理类设备》 6. 《中国联通 IMS 设备规范第三分册：互通类设备》 7. 《中国联通 IMS 设备测试规范第三分册：互通类设备》 8. 《中国联通 IMS 设备规范第四分册：媒体资源类设备》 9. 《中国联通 IMS 设备测试规范第四分册：媒体资源类设备》 10. 《中国联通 IMS 设备规范第五分册：基于承载的策略控制设备》 11. 《中国联通 IMS 设备测试规范第五分册：基于承载的策略控制设备》 12. 《中国联通 IMS 设备规范第六分册：计费设备》 13. 《中国联通 IMS 设备测试规范第六分册：计费设备》 14. 《中国联通 IMS 设备规范第七分册：业务服务器――与传统电路域语音呼叫连续性设备》 15. 《中国联通 IMS 设备测试规范第七分册：业务服务器――与传统电路域语音呼叫连续性设备》 16. 《中国联通 IMS 设备规范第八分册：业务服务器――短消息网关设备》 17. 《中国联通 IMS 设备测试规范第八分册：业务服务器――短消息网关设备》 18. 《中国联通 IMS 设备规范第九分册：业务服务器－智能网设备》 19. 《中国联通 IMS 设备测试规范第九分册：业务服务器－智能网设备》 20. 《中国联通 IMS 接口规范第一分册：Mw/Mg/Mi/Mj/Mk/Gm 接口》 21. 《中国联通 IMS 接口测试规范第一分册：Mw/Mg/Mi/Mj/Mk/Gm 接口》 22. 《中国联通 IMS 接口规范第二分册：Cx 接口》 23. 《中国联通 IMS 接口测试规范第二分册：Cx 接口》 24. 《中国联通 IMS 接口规范第三分册：Sh 接口》 25. 《中国联通 IMS 接口测试规范第三分册：Sh 接口》 26. 《中国联通 IMS 接口规范第四分册：ISC 接口》 27. 《中国联通 IMS 接口测试规范第四分册：ISC 接口》 28. 《中国联通 IMS 网络安全技术规范》 29. 《中国联通 IMS 网络安全测试规范》 30. 《中国联通 IMS 终端技术规范》 31. 《中国联通 IMS 终端测试规范》 32. 《中国联通 IMS 卡技术规范》 33. 《中国联通 IMS 卡测试规范》

本标准主要依据 3GPP R6、3GPP2 X.S0013 Rev.A、TISPAN Release1 相关的标准进行制定，同时包

含了 3GPPR7、3GPP2 X.S0013 Rev.B 中的部分功能。


IV

本标准由中国联通公司技术部提出并归口。本标准主要起草单位：中国联通研究设计院、中国联通公司技术部本标准主要起草人：王明会、顾旻霞、刘宝庆、杨征、王君珂、符刚、杨艳松、赫罡、朱爱华、蔡

子龙本标准的修改和解释权属中国联通公司。


1

中国联通 IMS 接口规范第一分册：

Mw/Mg/Mi/Mj/Mk/Gm 接口

1 范围

本标准规定了中国联通IMS网络中的SIP相关接口Mw/Mg/Mi/Mj/Mk/Gm的接口定义、接口功能、接口

协议、消息参数等。

本标准适用于中国联通IMS网络中的Mw/Mg/Mi/Mj/Mk/Gm接口，为中国联通IMS网络的规划、设计及

设备招标选型提供技术依据。

2 规范性引用文件

下列文件中的条款通过本标准的引用而成为本标准的条款。凡是注日期的引用文件，其随后所有的

修改单（不包括勘误的内容）或修订版均不适用于本标准，然而，鼓励根据本标准达成协议的各方研究

是否可使用这些文件的最新版本。凡是不注日期的引用文件，其最新版本适用于本标准。（以下3GPP

的规范暂定为2005年12月版，Release 6）

[1] 3GPP TS 23.002 V6.10.0: Network architecture; Stage 2

[2] 3GPP TS 23.218 v6.4.0: IM call model; Stage 2

[3] 3GPP TS23.228 v6.16.0: IP Multimedia Subsystem (IMS)

[4] 3GPP TS24.228 v5.15.0: Signalling flows for the IP multimedia call control based on Session Initiation Protocol (SIP) and Session Description Protocol (SDP)

[5] 3GPP TS24.229 v6.11.0: IP Multimedia Call Control Protocol based on Session Initiation Protocol (SIP) and Session Description Protocol (SDP)

[6] 3GPP TS 29.163 v6.10.0: Interworking between the IM CN subsystem and CS networks

[7] 3GPP TS29.228 v6.11.0: IP Multimedia (IM) Subsystem Cx and Dx interfaces;Signalling flows and message contents

[8] 3GPP TS29.229 v6.9.0: Cx and Dx interfaces based on the Diameter protocol;Protocol details

[9] 3GPP TS 29.332 v6.9.0: "Media Gateway Control Function (MGCF) – IM-Media Gateway (IM-MGW) interface, Stage 3"

[10] 3GPP TS 23.205 V6.7.0: "Bearer-independent circuit-switched core network; Stage 2"

[11] 3GPP TS 32.260v6.8.0: "Telecommunication management; Charging management; IP Multimedia Subsystem (IMS) charging"

[12] 3GPP2 X.S0013-002-A v1.0: All-IP Core Network Multimedia Domain - IP Multimedia Subsystem; Stage 2

[13] ETSI TS 182 006: IP Multimedia Subsystem (IMS); Stage 2 description

[14] IETF RFC 3261: "SIP: Session Initiation Protocol"


2

[15] IETF RFC 2327: "SDP: Session Description Protocol"

[16] IETF RFC 3550: "RTP: A Transport Protocol for Real-Time Applications"

[17] IETF RFC 3588: " Diameter Base Protocol".

3 缩略语

表1 缩略语

缩略语英文全称中文全称

API Application Program Interface 应用程序接口

AS Application Server 应用服务器

BGCF Breakout Gateway Control Function 出口网关控制功能

CDF Charging Data Function 计费数据功能

CDR Charging Data Record 计费数据记录

CGF Charging Gateway Function 计费网关功能

CN Core Network 核心网

CS Circuit Switched 电路交换

CSCF Call Session Control Function 呼叫会话控制功能

DHCP Dynamic Host Configuration Protocol 动态主机配置协议

DNS Domain Name System 域名系统

ENUM E.164 Number E.164 号码

GGSN Gateway GPRS Support Node 网关GPRS 支持节点

HSS Home Subscriber Server 归属用户服务器

IBCF Interconnection Border Control Function 互通边缘控制功能

ICID IMS Charging ID IMS 计费标识

I-CSCF Interrogating-CSCF 查询CSCF

IM IP Multimedia IP 多媒体

IMS IP Multimedia Core Network Subsystem IP多媒体网络子系统

ISIM IMS SIM IMS 用户标识模块

IP Internet Protocol 互联网协议

IM-MGW IP Multimedia Media Gateway Function IP多媒体网关功能

MGCF Media Gateway Control Function 媒体网关控制功能

MGW Media Gateway 媒体网关

MRFC Multimedia Resource Function Controller 多媒体资源控制功能

MRFP Multimedia Resource Function Processing 多媒体资源处理功能

OCS Online Charging System 在线计费系统

OSA Open Services Architecture 开放业务体系

P-CSCF Proxy-CSCF 代理CSCF

PDF Policy Decision Function 策略决策功能

PLMN Public Land Mobile Network 公众陆地移动网

PSI Public Service Identity 公共业务标识

PUI Public User Identity PUI


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PVI Private User Identity PVI

QoS Quality of Service 服务质量

SDP Session Description Protocol 会话描述协议

SGW Signalling Gateway 信令网关

SIP Session Initiated Protocol 会话初始协议

S-CSCF Serving-CSCF 服务CSCF

SGSN Serving GPRS Support Node 服务GPRS 支持节点

SLF Subscription Locator Function 签约位置功能

UE User Equipment 用户设备

URL Uniform Resource Locator 统一资源定位器

4 概述

4.1 IMS 网络架构 IMS总体网络架构如下图所示：

P-CSCF

I/S-CSCF

PCRF

AS (包括 VCC AS) HSS

BGCF

CS Domain

Other IPDomainMRFC

MRFP

IBCF

IM-MGW

MGCF

Other IMS Domain

IPv6/IPv4

CDMA RAN

SGSN/GGSN

TrGW

BGCF/IBCF

I/S-CSCF

SLF

CDMA UE

UMTS/GSM UE

Mw

Mw

Dx

DhISC Cx

Sh

Mw

Rx/Tx

Gx

Iu

Wi

Mb

Mb

Mr

Mp

MkMk

Mm

Mx

Mi

Mg Mj

Mx

Mn

Mm

Gm

WLAN UE

Ix

PDSN

UMTS RAN

WLAN

Gi

Ty

A10/A11

Pi

信令接口

承载或者信令 /承载接口

Ut

SGW

DNS/ENUM

xDSLaccess

xDSL UE

图1 IMS 总体网络架构

4.2 定义 SIP相关接口定义如下：

Mw接口：Mw接口在CSCF之间，基于SIP协议，支持IMS核心网络实体之间的所有信令流程，包括注册、会

话建立、更新、释放等。

Gm接口：Gm接口在终端和IMS网络之间，基于SIP协议，主要传输用户和CSCF之间的登记相关、用户业务

控制、鉴权相关的流程。


4

Mg接口：MGCF和CSCF之间的接口，基于SIP协议，用于描述电路交换网用户呼叫IMS用户流程，MGCF将

ISUP/BICC信令转换成SIP信令并转发SIP信令给CSCF。

Mi接口：BGCF和S-CSCF之间的接口，基于SIP协议，用于选择电路交换网的出口网关MGCF，当S-CSCF发

现会话需要被路由到电路交换网的时候，就使用Mi参考点将会话转发给BGCF。

Mj接口：BGCF和MGCF之间的接口，基于SIP协议，用于描述IMS用户呼叫同一IMS网络电路交换网用户流

程，在同一IMS网络进行BGCF和MGCF之间的消息交换。

Mk接口：BGCF和BGCF/I-CSCF之间的接口，基于SIP协议，用于描述IMS用户呼叫不同IMS网络电路交换网

用户流程，在不同IMS网络进行BGCF和BGCF之间的消息交换。

5 M 系列接口的协议

M系列接口使用SIP协议，基本协议遵照IETF RFC3261，并且应该支持SIP扩展的其他IETF规范，具

体扩展参见附录A和附录B。

6 接口相关消息和参数的传送

6.1 Mg 接口 6.1.1 概述

Mg 接口协议层次模型如下图所示。

IP

TCP/UDP

SIP / SDP

MgS-CSCF MGCF

IP

TCP/UDP

SIP / SDP

.

图2 Mg 接口协议层次模型

6.1.2 初始呼叫 6.1.2.1 电路交换网始发的呼叫

电路交换网发起的呼叫流程图如下所示：


5

MGW MGCF

Home Network

2. H.248 interactionto create connection

4. 100 Trying

5. 183 Session Progress

8. 200 OK

9. H.248 interactionto modify connectionto reserve resources

10. ResourceReservation

12. UPDATE

14. 180 Ringing

15. PRACK

17.ACM

1. IAM

3. INVITE

7. PRACK

11.COT

19.ANM

20. H.248 interaction tomodify connection to

start media flow

21. ACK

CS Networks

6. Bearer related negotiation(if any)

13. 200 OK

16. 200 OK

18. 200 OK

图3 电路交换网发起的呼叫

当 MGCF 在初始 INVITE 请求中收到来源于电路交换网的呼叫指示时，MGCF 必须产生 INVITE 请求给

I-CSCF： - 将 Request-URI 设置成 tel 格式的 E.164 地址 - 将 Supported 头设成 100rel - 根据电路域中的相应信息插入 P-Asserted-Identity 头 - 建立新的唯一的 icid 值并将其插入 P-Charging-Vector 头 - 并插入第二类 orig-ioi，第二类 orig-ioi 必须能够标识 MGCF 所在的网络，不得包含第二类 term-ioi - 说明本地 precondition 的状态 - 在 SDP 中说明 MGW 所支持的编码格式，MGW 最希望采用的编码格式排在最前 - 如果支持 DTMF，将 SDP 中的 MIME 子类型设为"telephone-event"

当发送SDP时，MGCF不能包括"i=", "u=", "e=", "p=", "r="和"z="；当接收SDP时忽略上述参数。

当 MGCF 收到 1XX 或 2XX 初始请求的回应消息时，MGCF 必须保存 P-Charging-Vector 头中的 term-ioi值以标识发送初始请求回应消息的网络。

当 MGCF 收到 INVITE 消息的 183 Session Progress 响应时，必须保存


6

P-Charging-Function-Addresses 头，并检查 SDP 中是否包含 MGW 所支持的 codec 列表

当MGCF收到PRACK的200 OK响应时，必须发送UPDATE请求。

MGCF向I-CSCF发送的INVITE消息示例如下：

INVITE tel:+1-212-555-2222 SIP/2.0 Via: SIP/2.0/UDP mgcf1.home1.net;branch=z9hG4bK779s24.0 Max-Forwards: 70 Route: <sip:icscf1_s.home1.net;lr> P-Asserted-Identity: <tel:+1-212-555-1111> P-Charging-Vector: icid-value="AyretyU0dm+6O2IrT5tAFrbHLso=023551024"; orig-ioi=home1.net Privacy: none From: <tel:+1-212-555-1111>;tag=171828 To: <tel:+1-212-555-2222> Call-ID: cb03a0s09a2sdfglkj490333 Cseq: 127 INVITE Require: precondition Supported: 100rel Contact: <sip:mgcf1.home1.net> Allow: INVITE, ACK, CANCEL, BYE, PRACK, UPDATE Content-Type: application/sdp Content-Length: (…) v=0 o=- 2987933615 2987933615 IN IP6 5555::aaa:bbb:ccc:ddd s=- c=IN IP6 5555::aaa:bbb:ccc:ddd t=0 0 m=audio 3456 RTP/AVP 97 96 b=AS:25.4 a=curr:qos local none a=curr:qos remote none a=des:qos mandatory local sendrecv a=des:qos none remote sendrecv a=rtpmap:97 AMR a=fmtp:97 mode-set=0,2,5,7; mode-change-period=2 a=rtpmap:96 telephone-event a=maxptime:20

Request-URI: 电路交换网用户的E.164号码

Via: MGCF的IP地址或FQDN

P-Asserted-Identity:MGCF插入从电路交换网获得的用户TEL URL

P-Charging-Vector:MGCF插入这个头并生成唯一的icid参数

Cseq:一个随机的起始号码

Contact:MGCF的IP地址或FQDN

SDP MGW所支持的codec列表

IMS域向MGCF回应的100 Trying消息示例如下：

SIP/2.0 100 Trying Via: SIP/2.0/UDP mgcf1.home1.net;branch=z9hG4bK779s24.0 From: To: Call-ID: CSeq: Content-Length: 0

IMS域向MGCF回应的183 Session Progress消息示例如下：

SIP/2.0 183 Session Progress Via: SIP/2.0/UDP mgcf1.home1.net;branch=z9hG4bK779s24.0 Record-Route: <sip:pcscf2.home1.net;lr>, <sip:scscf2.home1.net;lr> P-Asserted-Identity: "John Smith" <tel:+1-212-555-2222> P-Charging-Vector: icid-value="AyretyU0dm+6O2IrT5tAFrbHLso=023551024"; orig-ioi=home1.net;

term-ioi=visit1.net


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P-Charging-Function-Addresses: ccf=[5555::b99:c88:d77:e66]; ccf=[5555::a55:b44:c33:d22]; ecf=[5555::1ff:2ee:3dd:4cc]; ecf=[5555::6aa:7bb:8cc:9dd]

Privacy: none From: To: <tel:+1-212-555-2222>;tag=314159 Call-ID: CSeq: Require: 100rel Contact: <sip:[5555::eee:fff:aaa:bbb]:8805;comp=sigcomp> Allow: INVITE, ACK, CANCEL, BYE, PRACK, UPDATE, REFER, MESSAGE RSeq: 9021 Content-Type: application/sdp Content-Length: (…) v=0 o=- 2987933623 2987933623 IN IP6 5555::eee:fff:aaa:bbb s=- c=IN IP6 5555::eee:fff:aaa:bbb t=0 0 m=audio 6544 RTP/AVP 97 96 b=AS:25.4 a=curr:qos local none a=curr:qos remote none a=des:qos mandatory local sendrecv a=des:qos mandatory remote sendrecv a=conf:qos remote sendrecv a=rtpmap:97 AMR a=fmtp:97 mode-set=0,2,5,7; mode-change-period=2 a=rtpmap:96 telephone-event a=maxptime:20

P-Charging-Function-Addresses: S-CSCF将这个头传给MGCF用于计费

电路交换网向IMS域发送的PRACK消息示例如下：

PRACK sip:[5555::eee:fff:aaa:bbb]:8805;comp=sigcomp SIP/2.0 Via: SIP/2.0/UDP mgcf1.home1.net;branch=z9hG4bK779s24.0 Max-Forwards: 70 Route: <sip:scscf2.home1.net;lr>, <sip:pcscf2.home1.net;lr> From: <tel:+1-212-555-1111>;tag=171828 To: <tel:+1-212-555-2222>;tag=314159 Call-ID: cb03a0s09a2sdfglkj490333 Cseq: 128 PRACK Require: preconditions RAck: 9021 127 INVITE Content-Length: 0

Via: IP 地址或MGCF的FQDN

From:/To:/Call-ID: 同183 Session Progress

Cseq: 大于前一个请求的Cseq值

IMS域向MGCF发送PRACK的200OK响应消息示例如下：

SIP/2.0 200 OK Via: SIP/2.0/UDP mgcf1.home1.net;branch=z9hG4bK779s24.0 From: To: Call-ID: CSeq: Content-Length: 0

电路交换网发送给IMS域的UPDATE消息示例如下：

UPDATE sip:[5555::eee:fff:aaa:bbb]:8805;comp=sigcomp SIP/2.0 Via: SIP/2.0/UDP mgcf1.home1.net;branch=z9hG4bK779s24.0


8

Max-Forwards: 70 Route: <sip:scscf2.home1.net;lr>, <sip:pcscf2.home1.net;lr> From: <tel:+1-212-555-1111>;tag=171828 To: <tel:+1-212-555-2222>;tag=314159 Call-ID: cb03a0s09a2sdfglkj490333 Cseq: 129 UPDATE Content-Type: application/sdp Content-Length: (…) v=0 o=- 2987933615 2987933616 IN IP6 5555::aaa:bbb:ccc:ddd s=- c=IN IP6 5555::aaa:bbb:ccc:ddd t=0 0 m=audio 3456 RTP/AVP 97 96 b=AS:25.4 a=curr:qos local sendrecv a=curr:qos remote none a=des:qos mandatory local sendrecv a=des:qos mandatory remote sendrecv a=rtpmap:97 AMR a=fmtp:97 mode-set=0,2,5,7; mode-change-period=2 a=rtpmap:96 telephone-event a=maxptime:20

Via: IP 地址或MGCF的FQDN

Route: 保存的Route值（不包括第一条）

From:/To:/Call-ID: 同183 Session Progress

Cseq: 大于前一个请求的Cseq值

IMS域向MGCF发送UPDATE的200OK响应消息示例如下：

SIP/2.0 200 OK Via: SIP/2.0/UDP mgcf1.home1.net;branch=z9hG4bK779s24.0 From: To: Call-ID: CSeq: Content-Type: application/sdp Content-Length: (…) v=0 o=- 2987933623 2987933624 IN IP6 5555::aaa:bbb:ccc:ddd s=- c=IN IP6 5555::aaa:bbb:ccc:ddd t=0 0 m=audio 3456 RTP/AVP 97 96 b=AS:25.4 a=curr:qos local sendrecv a=curr:qos remote sendrecv a=des:qos mandatory local sendrecv a=des:qos mandatory remote sendrecv a=rtpmap:97 AMR a=fmtp:97 mode-set=0,2,5,7; mode-change-period=2 a=rtpmap:96 telephone-event a=maxptime:20

IMS域发送给MGCF的180 Ringing消息示例如下：

SIP/2.0 180 Ringing Via: SIP/2.0/UDP mgcf1.home1.net;branch=z9hG4bK779s24.0 Record-Route: <sip:pcscf2.home1.net;lr>, <sip:scscf2.home1.net;lr> Require: 100rel From: To:


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Call-ID: CSeq: 127 INVITE Contact: <sip:[5555::eee:fff:aaa:bbb]:8805;comp=sigcomp> Allow: INVITE, ACK, CANCEL, BYE, PRACK, UPDATE, REFER, MESSAGE RSeq: 9022 Content-Length: 0

电路交换网向IMS域发送对180 Ringing的PRACK响应信息示例如下：

PRACK sip:[5555::eee:fff:aaa:bbb]:8805;comp=sigcomp SIP/2.0 Via: SIP/2.0/UDP mgcf1.home1.net;branch=z9hG4bK779s24.0 Max-Forwards: 70 Route: <sip:scscf2.home1.net;lr>, <sip:pcscf2.home1.net;lr> From: <tel:+1-212-555-1111>;tag=171828 To: <tel:+1-212-555-2222>;tag=314159 Call-ID: cb03a0s09a2sdfglkj490333 Cseq: 130 PRACK RAck: 9022 127 INVITE Content-Length: 0

IMS域向MGCF发送对PRACK的200 OK响应信息示例如下：


IMS域向MGCF发送被叫用户应答的200 OK消息示例如下：

SIP/2.0 200 OK Via: SIP/2.0/UDP mgcf1.home1.net;branch=z9hG4bK779s24.0 Record-Route: <sip:pcscf2.home1.net;lr>, <sip:scscf2.home1.net;lr> From: To: Call-ID: CSeq: 127 INVITE Contact: <sip:[5555::eee:fff:aaa:bbb]:8805;comp=sigcomp> Allow: INVITE, ACK, CANCEL, BYE, PRACK, UPDATE, REFER, MESSAGE Content-Length: 0

电路交换网向IMS域发送对200 OK的ACK应答消息示例如下：

ACK sip:[5555::eee:fff:aaa:bbb]:8805;comp=sigcomp SIP/2.0 Via: SIP/2.0/UDP mgcf1.home1.net;branch=z9hG4bK779s24.0 Max-Forwards: 70 Route: <sip:scscf2.home1.net;lr>, <sip:pcscf2.home1.net;lr> From: To: Call-ID: Cseq: 127 ACK Content-Length: 0

Cseq：其值需要同INVITE中的Cseq值相同。

6.1.2.2 电路交换网终结的呼叫电路交换网终结的呼叫流程图如下所示：


10

MGWMGCF

Terminating Network

3. H.248 interaction to createconnection

2. 100 Trying


8. 200 OK

9. H.248 interaction to modifyconnection to reserve

resources


11. UPDATE

12. 200 OK

15. 180

16. PRACK

17. 200 OK

14. ACM / CPG

4. IAM

1. INVITE

7. PRACK

13. COT/IAM

20. 200 OK

18. ANM

19. H.248 interaction tomodify connection to start

media flow

21. ACK

PSTN/CS domain

5. Bearer related negotiation (in case BICC is used)

图4 电路交换域终结呼叫流程图

当MGCF收到IMS域的INVITE请求，若其中Supported头的值为100rel时，MGCF必须：

a) 存储 P-Charging-Vector header 中的 orig-ioi 参数 b) 向 IMS 域发送 100 Trying 消息 c) MGW 对 codec 没有要求或者找到匹配的 codec 之后向 IMS 域发送 183"Session Progress"

1) Require 头设成 100rel 2) 存储 P-Charging-Function-Addresses 中的参数值 3) 存储 P-Charging-Vector 头中的 icid 值 4) 向 P-Charging-Vector 插入从初始 INVITE 消息中携带的 orig-ioi 参数以及第二类 term-ioi

参数。第二类 term-ioi 参数必须设置为 MGCF 所在的网络，orig-ioi 参数必须设置为前面

所存储的 orig-ioi 值 5) 在 SDP 中说明所选择的 codec，并可以将 MIME 子类型设为"telephone-event"


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d) 如果 MGW 对 codec 有要求而 MGCF 没有在 MGW 找到相匹配的 codec，MGCF 必须 1) 如果 codec 类型可接受但不可用，回应 503 (Service Unavailable) 2) 如果 codec 类型不支持，回应 488(Not Acceptable Here)，并可以在消息体中包含

MGCF/MGW 所支持的 codec 当发送SDP时，MGCF不能包括"i=", "u=", "e=", "p=", "r=", and "z="；当接收SDP时忽略上述参

数

当MGCF收到电路交换网用户被叫振铃的指示，必须通过IMS域向主叫UE发送180 Ringing消息。

当 MGCF 收到电路交换网被叫用户应答的指示时，必须通过 IMS 域向主叫 UE 发送 200OK 消息。如果

从电路交换网域中收到了相应的信息，200OK 消息必须中包括 P-Asserted-Identity 头域。 IMS域向MGCF发送的INVITE消息示例如下：

INVITE tel:+1-212-555-2222 SIP/2.0 Via: SIP/2.0/UDP bgcf1.home1.net;branch=z9hG4bK6546q2.1, SIP/2.0/UDP

scscf1.home1.net;branch=z9hG4bK332b23.1, SIP/2.0/UDP pcscf1.home1.net;branch=z9hG4bK431h23.1, SIP/2.0/UDP [5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7

Max-Forwards: 67 Record-Route: <sip:scscf1.home1.net;lr>, <sip:pcscf1.home1.net;lr> P-Asserted-Identity: "John Doe" <tel:+1-212-555-1111> P-Charging-Vector: icid-value="AyretyU0dm+6O2IrT5tAFrbHLso=023551024" P-Charging-Function-Addresses: ccf=[5555::b99:c88:d77:e66]; ccf=[5555::a55:b44:c33:d22];

ecf=[5555::1ff:2ee:3dd:4cc]; ecf=[5555::6aa:7bb:8cc:9dd] Privacy: none From: <sip:[email protected]>;tag=171828 To: <tel:+1-212-555-2222> Call-ID: cb03a0s09a2sdfglkj490333 Cseq: 127 INVITE Require: precondition Supported: 100rel Contact: <sip:[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp> Allow: INVITE, ACK, CANCEL, BYE, PRACK, UPDATE, REFER, MESSAGE Content-Type: application/sdp Content-Length: (…) v=0 o=- 2987933615 2987933615 IN IP6 5555::aaa:bbb:ccc:ddd s=- c=IN IP6 5555::aaa:bbb:ccc:ddd t=0 0 m=video 3400 RTP/AVP 98 99 b=AS:75 a=curr:qos local none a=curr:qos remote none a=des:qos mandatory local sendrecv a=des:qos none remote sendrecv a=rtpmap:98 H263 a=fmtp:98 profile-level-id=0 a=rtpmap:99 MP4V-ES m=audio 3456 RTP/AVP 97 96 b=AS:25.4 a=curr:qos local none a=curr:qos remote none a=des:qos mandatory local sendrecv a=des:qos none remote sendrecv a=rtpmap:97 AMR

a=fmtp:97 mode-set=0,2,5,7; mode-change-period=2

a=rtpmap:96 telephone-event

a=maxptime:20

P-Charging-Vector: S-CSCF 把这个参数传给 MGCF 用于计费。如果 S-CSCF 和 MGCF 属于不同网络，

则必须包括 orig-ioi，并且在 183 Session Progress 消息中包括 term-ioi； P-Charging-Function-Addresses: 如果 MGCF 和 S-CSCF 在同一网络，S-CSCF 插入这个头以向 MGCF


12

提供计费地址信息；如果两者不在同一网络则不包括这个头。

MGCF向IMS域发送对INVITE的100 Trying响应消息示例如下：

SIP/2.0 100 Trying Via: SIP/2.0/UDP bgcf1.home1.net;branch=z9hG4bK6546q2.1, SIP/2.0/UDP


From: To: Call-ID: CSeq: Content-Length: 0

MGCF向IMS域发送的183Session Progress消息示例如下：

SIP/2.0 183 Session Progress Via: SIP/2.0/UDP bgcf1.home1.net;branch=z9hG4bK6546q2.1, SIP/2.0/UDP


Record-Route: <sip:scscf1.home1.net;lr>, <sip:pcscf1.home1.net;lr> P-Asserted-Identity: <tel:+1-212-555-2222> P-Charging-Vector: Privacy: none From: To: <tel:+1-212-555-2222>;tag=314159 Call-ID: CSeq: Require: 100rel Contact: <sip:mgcf1.home1.net> Allow: INVITE, ACK, CANCEL, BYE, PRACK, UPDATE RSeq: 9021 Content-Type: application/sdp Content-Length: (…) v=0 o=- 2987933623 2987933623 IN IP6 5555::eee:fff:aaa:bbb s=- c=IN IP6 5555::eee:fff:aaa:bbb t=0 0 m=video 0 RTP/AVP 98 99 m=audio 6544 RTP/AVP 97 96 b=AS:25.4 a=curr:qos local none a=curr:qos remote none a=des:qos mandatory local sendrecv a=des:qos none remote sendrecv a=conf:qos remote sendrecv a=rtpmap:97 AMR a=fmtp:97 mode-set=0,2,5,7; mode-change-period=2 a=rtpmap:96 telephone-event a=maxptime:20

IMS域向电路交换网发送的PRACK消息示例如下：

注：其中没有包括SDP消息是因为这个示例中只有一种媒体流和一种编码方式。

PRACK sip:mgcf1.home1.net SIP/2.0 Via: SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1, SIP/2.0/UDP

pcscf1.home1.net;branch=z9hG4bK431h23.1, SIP/2.0/UDP [5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7

Max-Forwards: 68 From: <sip:[email protected]>;tag=171828 To: <tel:+1-212-555-2222>;tag=314159 Call-ID: cb03a0s09a2sdfglkj490333 Cseq: 128 PRACK


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RAck: 9021 127 INVITE Content-Length: 0

MGCF向IMS域发送对PRACK的200 OK响应消息示例如下：

SIP/2.0 200 OK Via: SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1, SIP/2.0/UDP



IMS域发送给电路交换网的UPDATE消息示例如下：

UPDATE sip:mgcf1.home1.net SIP/2.0 Via: SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1, SIP/2.0/UDP


Max-Forwards: 68 From: <sip:[email protected]>;tag=171828 To: <tel:+1-212-555-2222>;tag=314159 Call-ID: cb03a0s09a2sdfglkj490333 Cseq: 129 UPDATE Content-Type: application/sdp Content-Length: (…) v=0 o=- 2987933615 2987933616 IN IP6 5555::aaa:bbb:ccc:ddd s=- c=IN IP6 5555::aaa:bbb:ccc:ddd t=0 0 m=video 0 RTP/AVP 98 99 m=audio 3456 RTP/AVP 97 96 b=AS:25.4 a=curr:qos local sendrecv a=curr:qos remote none a=des:qos mandatory local sendrecv a=des:qos mandatory remote sendrecv a=rtpmap:97 AMR a=fmtp:97 mode-set=0,2,5,7; mode-change-period=2 a=rtpmap:96 telephone-event a=maxptime:20

MGCF向IMS域发送对UPTDATE的200 OK响应消息示例如下：



From: To: Call-ID: CSeq: Content-Type: application/sdp Content-Length: (…) v=0 o=- 2987933623 2987933623 IN IP6 5555::aaa:bbb:ccc:ddd s=- c=IN IP6 5555::aaa:bbb:ccc:ddd t=0 0 m=video 0 RTP/AVP 98 99 m=audio 6544 RTP/AVP 97 96 b=AS:25.4


14

a=curr:qos local sendrecv a=curr:qos remote sendrecv a=des:qos mandatory local sendrecv a=des:qos mandatory remote sendrecv a=rtpmap:97 AMR a=fmtp:97 mode-set=0,2,5,7; mode-change-period=2 a=rtpmap:96 telephone-event a=maxptime:20

MGCF向IMS域发送180 Ringing消息示例如下：

SIP/2.0 180 Ringing Via: SIP/2.0/UDP bgcf1.home1.net;branch=z9hG4bK6546q2.1, SIP/2.0/UDP


Record-Route: <sip:scscf1.home1.net;lr>, <sip:pcscf1.home1.net;lr> Require: 100rel From: To: Call-ID: CSeq: 127 INVITE Contact: <sip:mgcf1.home1.net> Allow: INVITE, ACK, CANCEL, BYE, PRACK, UPDATE RSeq: 9022 Content-Length: 0

注：只有ACM消息只是被叫在振铃的情况下，才会产生180 Ringing消息。

IMS域向电路交换网发送对180的PRACK响应消息示例如下：



Max-Forwards: 68 From: <sip:[email protected]>;tag=171828 To: <tel:+1-212-555-2222>;tag=314159 Call-ID: cb03a0s09a2sdfglkj490333 Cseq: 130 PRACK RAck: 9022 127 INVITE Content-Length: 0

MGCF向IMS域发送对PRACK的200 OK响应消息示例如下：




MGCF向IMS域发送被叫用户应答的200 OK消息示例如下：

SIP/2.0 200 OK Via: SIP/2.0/UDP bgcf1.home1.net;branch=z9hG4bK6546q2.1, SIP/2.0/UDP


Record-Route: <sip:scscf1.home1.net;lr>, <sip:pcscf1.home1.net;lr> From: To: Call-ID: CSeq: 127 INVITE


15

Contact: <sip:mgcf1.home1.net> Allow: INVITE, ACK, CANCEL, BYE, PRACK, UPDATE Content-Length: 0

IMS域向电路交换网发送对200 OK的ACK响应消息示例如下：

ACK sip:mgcf1.home1.net SIP/2.0 Via: SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1, SIP/2.0/UDP


Max-Forwards: 68 From: To: Call-ID: Cseq: 127 ACK Content-Length: 0

6.1.3 呼叫释放 6.1.3.1 电路交换网发起的呼叫释放

当电路交换网收到呼叫释放指示时，MGCF必须通过IMS域向UE发送BYE消息。

S-CSCFUE

Home Network

MGCFIP-CAN

Visited Network

4. Release Resources

12. Rls Response

1.REL

10. SIP OK

MGW

PSTN Network

7. Hangup

P-CSCF/PCF

13. SIP OK

2. Hangup

5. Rls Response

9. Hangup

3. RLC

11. Release resources14. SIP OK

6. Service Control

8. Remove authorisationfor bearer resources

图5 电路交换网发起的呼叫释放

6.1.3.2 IMS 域发起的呼叫释放当从IMS域收到BYE消息时，MGCF必须向电路交换网发起呼叫释放请求。


16

图6 IMS 域发起的呼叫释放

6.1.3.3 MGW 发起的呼叫释放当从MGW收到承载丢失的指示时，MGCF必须通过IMS域向UE发送BYE消息。

图7 MGW 发起的呼叫释放

6.2 Mi 接口 6.2.1 概述

Mi 接口位于 BGCF 与 S-CSCF 之间，用于选择电路域的出口网关 MGCF. S-CSCF 转发 SIP 请求或者

响应消息到 BGCF，进而路由到电路交换网。

Mi 接口协议栈如下图所示：


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IP

TCP/UDP

SIP / SDP

Mi S-CSCF BGCF

IP

TCP/UDP

SIP / SDP

图8 Mi 接口协议层次模型

S-CSCF 将不能直接查询到下一跳路由的 SIP 初始 Invite 消息传递给 BGCF。S-CSCF 应该支持

Request-URI E.164 地址翻译功能，如果该翻译成功，会话按照返回的 SIP URI.路由。如果翻译失败，

会话将路由至 BGCF。

BGCF不需要支持 Path 和 Service-Route头域的要求。

6.2.2 会话初始化事务的处理 BGCF 接收到 INVITE 消息后, 应该将该请求消息转发到本网内的 MGCF 。S-CSCF 与 BGCF 间寻址可

以通过网络配置策略完成，通常 S-CSCF 通过静态配置的本地 BGCF 完成 MGCF 的选择.

BGCF 不需要记录INVITE 消息的Record-Route. 由于BGCF 的下一个转接网元可能是一个具有UA功能的 MGCF, BGCF 不要按照 RFC 3323 实现 privacy。

BGCF收到Mi 接口的SIP初始 Invite 消息，

a) 首先分析 SIP Invite 的 Request-URI 的电话号码，比较事先配置的编号方案选择 MGCF 或者

BGCF。为了成功完成选择，每个 Request-URI 的电话号码都应该与特定的 MGCF 或者 BGCF 相关

联.

b) BGCF 应该检查 SDP 内容，比如，audio 和 video。如果 SIP INVITE 中 m=video, BGCF 应该

选择支持 video 的 MGCF；如果 m=audio only, 可以选择只支持 audio 的 MGCF 。

c) 如果一个 non-video 会话被 SIP UPDATE 或者 SIP re-INVITE 消息更新为 m=video 的会话，该

请求可能被拒绝因为已选择的 MGCF 不支持 video。

6.2.3 S-CSCF 选择 BGCF 当 S-CSCF 判断该会话应该路由至电路交换网时，S-CSCF 会将 Invite 消息转交给本网络的 BGCF。

BGCF 根据本地策略选择互通的目的网络。该选择的流程如下图所示

Receipt of SIPinvite

S-CSCF determines ifthe session is to be continued in IM CN

or in GSTN?

Continue withSIP routing

BGCF selects network

BGCF selects &forwards

the signallingto the MGCF

BGCF forwardssignalling tothe selected

network

Same network

To GSTN via Network

Other networkContinued viaIM CN subsystem


18

图9 S-CSCF 选择 BGCF

6.2.4 PSTN 终结呼叫流程（包括资源预留） PSTN终结呼叫流程如下图所示：

S-CSCF BGCF

1. Invite (Initial SDP Offer)


8. Response Conf (Opt SDP)

11. Conf Ack (Opt SDP)



15. Reservation Conf16. Reservation Conf

17. Reservation Conf18. Reservation Conf

14. Reservation Conf

Originating Home NetworkOriginatingNetwork

TerminatingNetwork


5. Offer Response6. Offer Response

7. Offer Response



19. Reservation Conf

28. ACK

26. ACK27. ACK

23. 200 OK24. 200 OK

25. 200 OK

20. Ringing21. Ringing

22. Ringing

2. Service Control

图10 PSTN 终结呼叫流程示例（本网）

1.UE发送SIP INVITE给S-CSCF#1 ，本消息应带有初始媒体描述。

2.S-CSCF#1执行本地业务控制；

3.S-CSCF#1分析目的地址，确定该呼叫终结于PSTN, SIP请求消息转交给BGCF.

4.BGCF判断下一跳为本网MGCF，选择下一跳，将SIP INVITE消息转交MGCF.

5-7.被叫媒体能力沿路由返回

8.发起方回应Response Confirmation并确认SDP Offer

9-10.S-CSCF#1 按照建立的路由转交SDP Offer

11-13.被叫方响应回复的SDP offer

14-16.完成资源预留，发起方发送 S-CSCF#1 预留消息

17-19.终结方按照已有的信令路由回应预留确认


19

20-22.终结方返回给 BGCF 振铃消息，BGCF 进一步转发给SCSCF#1

23. 终结方回复SIP 200-OK 给 BGCF

24-25.The BGCF发送信息给S-CSCF#1，进一步转交给发起方

26-28.ACK按照已有路由转交给被叫方。

各消息具体内容示例如下：

INVITE (S-CSCF to BGCF)：

INVITE tel:+1-212-555-2222 SIP/2.0 Via: SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1, SIP/2.0/UDP


Max-Forwards: 68 Route: <sip:bgcf1.home1.net;lr> Record-Route: <sip:scscf1.home1.net;lr>, <sip:pcscf1.home1.net;lr> P-Asserted-Identity: P-Charging-Vector: P-Charging-Function-Addresses: ccf=[5555::b99:c88:d77:e66]; ccf=[5555::a55:b44:c33:d22];

ecf=[5555::1ff:2ee:3dd:4cc]; ecf=[5555::6aa:7bb:8cc:9dd] Privacy: From: To: Call-ID: Cseq: Require: Supported: Contact: Allow: Content-Type: Content-Length: (…) v= o= s= c= t= m= b= a= a= a= a= a= a= a= m= b= a= a= a= a= a= a= a= a=

100 Trying (BGCF to S-CSCF)：

SIP/2.0 100 Trying Via: SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1, SIP/2.0/UDP


From: To: Call-ID: CSeq:


20

Content-Length: 0

183 Session Progress (BGCF to S-CSCF)：

SIP/2.0 183 Session Progress Via: SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1, SIP/2.0/UDP

pcscf1.home1.net;branch=z9hG4bK431h23.1, SIP/2.0/UDP [5555::aaa:bbb:ccc:ddd]:1357;comp=sigcopm;branch=z9hG4bKnashds7

Record-Route: P-Asserted-Identity: P-Charging-Vector: Privacy: From: To: Call-ID: CSeq: Require: Contact: Allow: RSeq: Content-Type: Content-Length: v= o= s= c= t= m= m= b= a= a= a= a= a= a= a= a= a=

180 Ringing (BGCF to S-CSCF)：

SIP/2.0 180 Ringing Via: SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1, SIP/2.0/UDP


Record-Route: From: To: Call-ID: CSeq: Require: Contact: Allow: RSeq: Content-Length:

200 OK (BGCF to S-CSCF)：



Record-Route:


21

From: To: Call-ID: CSeq: Contact: Allow: Content-Length:

6.2.5 CS 被叫流程

S-CSCF BGCF



Terminating Home NetworkOriginatingNetwork


2. Service Control

MGCF

5. Session SetupContinues

图11 呼叫终结于 CS 注册用户

1. SIP Invite路由至 S-CSCF。

2. S-CSCF进行本地业务控制。

3. S-CSCF 分析地址，判断将该会话消息路由至BGCF。

4. BGCF 转交 SIP INVITE给合适的MGCF或者外网的 BGCF。

5. 以下流程参照7.2.3。

INVITE (S-CSCF to BGCF)：

INVITE tel:+1-212-555-2222 SIP/2.0 Via: SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1, SIP/2.0/UDP


Max-Forwards: 68 Route: <sip:bgcf1.home1.net;lr> Record-Route: <sip:scscf1.home1.net;lr>, <sip:pcscf1.home1.net;lr> P-Asserted-Identity: P-Charging-Vector: P-Charging-Function-Addresses: ccf=[5555::b99:c88:d77:e66]; ccf=[5555::a55:b44:c33:d22];

ecf=[5555::1ff:2ee:3dd:4cc]; ecf=[5555::6aa:7bb:8cc:9dd] Privacy: From: To: Call-ID: Cseq: Require: Supported: Contact: Allow: Content-Type: Content-Length: (…) v= o= s= c=


22

t= m= b= a= a= a= a= a= a= a= m= b= a= a= a= a= a= a= a= a=

6.3 Mj 接口 6.3.1 概述：

Mj 接口位于 BGCF 与 MGCF 之间，用于在 BGCF 和 MGCF 之间发送请求或者响应.BGCF 转发 SIP 请求

或者响应消息到 MGCF，进而路由到电路交换网。

Mj接口协议栈如下图所示：

IP

TCP/UDP

SIP / SDP

Mj BGCF MGCF

IP

TCP/UDP

SIP / SDP

图12 Mj 接口协议层次模型

Mj接口使用SIP协议，基本协议遵照IETF RFC3261，及其SIP扩展的其他IETF规范。Mj接口相关消息

和参数的传递还需遵循如下规定：

1) Mj接口不应支持Service-Route和Path消息头；

2) 当BGCF转发任何对话相关或独立事务处理的SIP请求/响应(除ACK/CANCEL请求及其响应)至

MGCF时, 可以插入以前存储的P-Charging-Vector和P-Charging-Function-Address；

3) BGCF在转发INVITE请求至MGCF时, 不需要添加Record-Route消息头；如果需要添加

Record-Route消息头, BGCF可以根据RFC4028要求进行会话的刷新 (Refreshment)；

4) BGCF在转发INVITE请求至MGCF时, BGCF应不执行RFC 3323中关于Privacy的相关处理；

5) BGCF应存储收到的P-Charging-Vector中的icid参数, P-Charging-Function-Address；

6) 除上述规定和RFC 3261中Stateful Proxy的相关处理外, BGCF应能透传收到的SIP消息和响应。

6.3.2 电路交换网被叫流程 Mj 接口的会话流程如下图所示：


23

4. INVITE

19. 180 Ringing

S-CSCF MGCF

8. 183 SessionProgress

11. PRACK

22. PRACK

26. 200 OK

15. UPDATE

29. ACK

BGCF

6. INVITE


1. INVITE


21. 180 Ringing

28. 200 OK

Home NetworkOriginating Network

20. 180 Ringing

27. 200 OK

2. 100 Trying

7. 100 Trying

12. PRACK

5. 100 Trying

13. 200 OK14. 200 OK

16. UPDATE

17. 200 OK18. 200 OK

23. PRACK

24. 200 OK25. 200 OK

30. ACK

3. Evaluation ofinitial filter criterias

图13 电路交换网被叫流程图

在上面的流程图中，BGCF收到来自S-CSCF发送来的Invite消息后，BGCF会分析目的地址，分配一个

MGCF来处理会话请求，并将Invite请求转发给MGCF。

Invite 消息（BGCF to MGCF）中字段如下：



Max-Forwards: 67 Route: <sip:mgcf1.home1.net;lr> Record-Route: P-Asserted-Identity: P-Charging-Vector: P-Charging-Function-Addresses: Privacy: From: To: Call-ID: Cseq:


24

Require: Supported: Contact: Allow: Content-Type: Content-Length: v= o= s= c= t= m= b= a= a= a= a= a= a= a= m= b= a= a= a= a= a= a= a= a=

MGCF 收到 BGCF 的 Invite 消息后，临时回应一个 100 Trying 消息（MGCF to BGCF）：




MGCF 返回 183 Session Progress 消息给 BGCF：



Record-Route: <sip:scscf1.home1.net;lr>, <sip:pcscf1.home1.net;lr> P-Asserted-Identity: "John Smith" <tel:+1-212-555-2222> P-Charging-Vector: icid-value="AyretyU0dm+6O2IrT5tAFrbHLso=023551024"; term-ioi=home1.net Privacy: none From: To: <tel:+1-212-555-2222>;tag=314159 Call-ID: CSeq: Require: 100rel Contact: <sip:mgcf1.home1.net> Allow: INVITE, ACK, CANCEL, BYE, PRACK, UPDATE RSeq: 9021 Content-Type: application/sdp Content-Length: (…)


25

v=0 o=- 2987933623 2987933623 IN IP6 5555::eee:fff:aaa:bbb s=- c=IN IP6 5555::eee:fff:aaa:bbb t=0 0 m=video 0 RTP/AVP 98 99 m=audio 6544 RTP/AVP 97 96 b=AS:25.4 a=curr:qos local none a=curr:qos remote none a=des:qos mandatory local sendrecv a=des:qos mandatory remote sendrecv a=conf:qos remote sendrecv a=rtpmap:97 AMR a=fmtp:97 mode-set=0,2,5,7;mode-change-period =2 a=rtpmap:96 telephone-event a=maxptime:20

在流程 19 步中， MGCF 发送一个 180 Ringing 回应消息给 BGCF：



Record-Route: <sip:scscf1.home1.net;lr>, <sip:pcscf1.home1.net;lr> From: To: Call-ID: CSeq: 127 INVITE Require: 100rel Contact: <sip:mgcf1.home1.net> Allow: INVITE, ACK, CANCEL, BYE, PRACK, UPDATE RSeq: 9022 Content-Length: 0

MGCF 返回 200 OK（26 步）给 BGCF：



Record-Route: <sip:scscf1.home1.net;lr>, <sip:pcscf1.home1.net;lr> From: To: Call-ID: CSeq: 127 INVITE Contact: <sip:mgcf1.home1.net> Allow: INVITE, ACK, CANCEL, BYE, PRACK, UPDATE Content-Length: 0

6.4 Mk 接口 6.4.1 概述

Mk接口使用SIP协议，基本协议遵照IETF RFC3261，及其SIP扩展的其他IETF规范，不支持Path和

Service-Route头字段的应用，同时不能应用RFC 3323中与与私密性相关的处理流程。

当BGCF接收到请求时，将根据从其它协议或数据库获得的信息，决定请求的路由。如果需要将请求

前转到其他网络，则通过Mk接口将请求前转到其他网络的BGCF。如果根据本地策略要求IBCF功能，这将

请求先前转到本网络的IBCF，再由IBCF前转到其他网络。

BGCF应该保存接收到的P-Charging-Function-Addresses头字段和P-Charging-Vector头字段icid

参数中的值，可以在前转接到后续请求和响应（除了ACK和CANCEL请求和响应）之前，插入保存的值。


26

在向下一个BGCF前转时，BGCF不需要修改Request-URI，同时不需要在INVITE请求插入Record-Route。

如果BGCF要求应用Record-Route，则BGCF要求会话定时刷新功能，以避免会话挂起。

6.4.2 接口流程 Mk 接口的流程如下图所示：

4. INVITE

22. 180 (Ringing)

S-CSCF MGCF

10. 183 (SessionProgress)

14. PRACK

26. PRACK

30. 200 (OK)

18. UPDATE

34. ACK

BGCF#1 BGCF#2

6. INVITE


1. INVITE


25. 180 (Ringing)

33. 200 (OK)

Terminating NetworkOriginating Network

24. 180 (Ringing)

32. 200 (OK)

2. 100 (Trying)

7. 100 (Trying)

5. 100 (Trying)

16. 200 (OK)17. 200 (OK)

21. 200 (OK)

28. 200 (OK)29. 200 (OK)


8. INVITE9. 100 (Trying)


15. PRACK

19. UPDATE

20. 200 (OK)

23. 180 (Ringing)

27. PRACK

31. 200 (OK)

35. ACK

Home Network

图14 Mk 接口流程

1.INVITE请求由UE通过主叫流程发送到S-CSCF#1，这个INVITE请求中的SDP应包含发起方提供的媒

体描述；

2. S-CSCF#1 发送 100trying 临时响应给 UE；

3.S-CSCF#1 触发适合这个会话要建立的服务逻辑；


27

4.S-CSCF#1 通过分析目的地址，发现被叫用户为电路交换网用户，S-CSCF#1 就把 INVITE 请求发送

到 BGCF#1；

5.BGCF#1 发送 100trying 临时响应给 S-CSCF#1；

6.BGCF#1分析后发现被叫用户属于它域用户，就把INVITE请求发给BGCF#2。如果需要拓扑隐藏，

INVITE请求需要发往I-CSCF；

7.BGCF#2 发送 100trying 临时响应给 BGCF#1；

8.BGCF#2 在本域内选择一个合适的 MGCF，并将 INVITE 请求发给 MGCF；

9.MGCF 发送 100trying 临时响应给 BGCF#2；

10.MGCF 发送 183 Session Progress 消息给 BGCF#2，183 Session Progress 消息包含被叫的媒体

流能力；

11. BGCF#2 发送 183 Session Progress 会话过程临时响应给 BGCF#1；

12. BGCF#1 进一步转发 183 Session Progress 消息给 S-CSCF#1；

13.S-CSCF#1 转发 183 Session Progress 消息给 UE；

14.主叫方发送PRACK消息给S-CSCF#1,因为在SDP的offer/answer协商结果只使用一种媒体流和编

码格式，所以PRACK没有携带SDP；

15.S-CSCF#1 转发 PRACK 消息给 MGCF；

16.MGCF 发送响应 PRACK 的 200OK 给 S-CSCF#1；

17.S-CSCF#1 转发 200OK 给发起方；

18.当发起方完成资源预留后，就沿着主叫流程发送 UPDATE 消息给 S-CSCF#1；

19.S-CSCF#1 转发 UPDATE 消息给 MGCF；

20. MGCF 发送响应 UPDATE 的 200OK 给 S-CSCF#1；

21. S-CSCF#1 转发 200OK 给发起方；

22.MGCF 会发送 180 ringing 给 BGCF#2,表明被叫正在振铃；

23.BGCF#2 转发 180 ringing 给 BGCF#1；

24.BGCF#1 进一步转发 180 ringing 给 S-CSCF#1；

25.S-CSCF#1 沿着主叫流程发送 180 ringing 给主叫方；

26.主叫方发送 PRACK 临时消息给 S-CSCF#1，来响应 180 ringing；

27.S-CSCF#1 转发 PRACK 给 MGCF；

28.MGCF 发送 200OK 消息给 S-CSCF#1，以响应 PRACK 消息；

29.S-CSCF#1 进一步转发最终响应 200OK 消息给主叫方；

30.当被叫用户接受了来话请求后，MGCF 发送最终响应 200OK 消息给 BGCF#2；

31.BGCF#2 转发最终响应 200OK 给 BGCF#1；

32.BGCF#1 进一步转发最终响应 200OK 给 S-CSCF#1；

33.S-CSCF#1 发送最终响应 200OK 给主叫方；

34.主叫方发送最终应答消息 ACK 给 S-CSCF#1；

35.S-CSCF#1 转发最终应答消息 ACK 给 MGCF；

Mk 接口的各消息具体内容如下：

INVIE 消息（BGCF#1 to BGCF#2）



Max-Forwards: 67 Route: <sip:bgcf2.home2.net;lr> Record-Route:


28

P-Asserted-Identity: P-Charging-Vector: Privacy: From: To: Call-ID: Cseq: Require: Supported: Contact: Allow: Content-Type: Content-Length: v= o= s= c= t= m= b= a= a= a= a= a= a= a= m= b= a= a= a= a= a= a= a= a=

183 Session Progress 消息（BGCF#2 to BGCF#1）



Record-Route: P-Asserted-Identity: P-Charging-Vector: Privacy: From: To: Call-ID: CSeq: Require: Contact: Allow: RSeq: Content-Type: Content-Length: v= o= s= c= t= m= m= b=


29

a= a= a= a= a= a= a= a= a=

180 ringing（BGCF#2 to BGCF#1）




200 OK（BGCF#2 to BGCF#1）

SIP/2.0 200 OK Via: SIP/2.0/UDP bgcf1.home.net;branch=z9hG4bK6546q2.1, SIP/2.0/UDP


Record-Route: From: To: Call-ID: CSeq: Contact: Allow: Content-Length:

6.5 Mw 接口 6.5.1 注册消息 6.5.1.1 用户初始注册


30

UE P-CSCF(pcscf1)

DNS I-CSCF(icscf1_1)

S-CSCF(scscf1)

HSS

Visited Network (visited1.net) Home Network (home1.net)

1. REGISTER

2. DNS: DNS-Q

3. REGISTER

5. REGISTER

18. Cx: S-CSCFregistratio

nnotification

19. 200 OK

20. 200 OK

21.200 OK

4. Cx: User registration status query

6.Authenticatio

n

8. 401Unauthorized

9. 401 Unauthorized

10. 401 Unauthorized

12. REGISTER

13. DNS: DNS-Q

14. REGISTER

16. REGISTER


7.Vector

Selection

11.of Response

andsession keys

17.Authentication

图15 用户初始注册流程


31

Register 消息（P-CSCF to I-CSCF）

REGISTER sip:registrar.home1.net SIP/2.0 Via: SIP/2.0/UDP pcscf1.visited1.net;branch=z9hG4bK240f34.1, SIP/2.0/UDP

[5555::aaa:bbb:ccc:ddd];comp=sigcomp;branch=z9hG4bKnashds7 Max-Forwards: 69 P-Access-Network-Info: Path: <sip:[email protected];lr> Require: path P-Visited-Network-ID: "Visited Network Number 1" P-Charging-Vector: icid-value="AyretyU0dm+6O2IrT5tAFrbHLso=023551024" From: To: Contact: Call-ID: Authorization: Digest username="[email protected]", realm="registrar.home1.net",

nonce="", uri="sip:registrar.home1.net", response="", integrity-protected="no" CSeq: Supported: Content-Length:

Path:P-CSCF 的地址，用于通知 S-CSCF 被叫请求的路由地址。

Require:此头域能保证接受端能正确处理 Path 头域，如果接受端不支持 Path 头域，就会返回 420

消息并携带 Unsupported 头域，指示不支持 Path 头域。这个响应表明路由表配置错误以及请求被路由

到了 IMS 域外。 P-Visited-Network-ID:P-CSCF 所在归属网络的网络。

P-Charging-Vector:P-CSCF 插入此头域作为 ICID 参数，ICID 参数是唯一的。

Register（I-CSCF to S-CSCF）：

REGISTER sip:scscf1.home1.net SIP/2.0 Via: SIP/2.0/UDP icscf1_p.home1.net;branch=z9hG4bK351g45.1, SIP/2.0/UDP

pcscf1.visited1.net;branch=z9hG4bK240f34.1, SIP/2.0/UDP [5555::aaa:bbb:ccc:ddd];comp=sigcomp;branch=z9hG4bKnashds7

Max-Forwards: 68 P-Access-Network-Info: Path: Require: P-Visited-Network-ID: P-Charging-Vector: From: To: Contact: Call-ID: Authorization: CSeq: Supported: Content-Length:

P-Access-Network-Info:包含从 UE 携带的信息。

Path:I-CSCF 不更改 Path 头域的值，S-CSCF 保存 Path 头域值，作为被叫请求的 URI。

401 未授权响应 (S-CSCF to I-CSCF)

SIP/2.0 401 Unauthorized Via: SIP/2.0/UDP icscf1_p.home1.net;branch=z9hG4bK351g45.1, SIP/2.0/UDP


From: <sip:[email protected]>;tag=4fa3 To: <sip:[email protected]>; tag=5ef4 Call-ID: apb03a0s09dkjdfglkj49111 WWW-Authenticate: Digest realm="registrar.home1.net", nonce=base64(RAND + AUTN + server specific

data), algorithm=AKAv1-MD5, ik="00112233445566778899aabbccddeeff", ck="ffeeddccbbaa11223344556677889900"

CSeq: 1 REGISTER


32

Content-Length: 0

WWW-Authenticate：S-CSCF 挑战用户，nonce 主要包括 AKA RAND、AKA AUTN 和其它数据。

IK 和 CK 数据也在此消息中。

401 未授权响应 (I-CSCF to P-CSCF)

SIP/2.0 401 Unauthorized Via: SIP/2.0/UDP pcscf1.visited1.net;branch=z9hG4bK240f34.1, SIP/2.0/UDP

[5555::aaa:bbb:ccc:ddd];comp=sigcomp;branch=z9hG4bKnashds7 From: To: Call-ID: WWW-Authenticate: CSeq: Content-Length:

REGISTER 请求 (P-CSCF to I-CSCF)


[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 Max-Forwards: 69 P-Access-Network-Info: Path: <sip:[email protected];lr> Require: path P-Visited-Network-ID: "Visited Network Number 1" P-Charging-Vector: icid-value="AyretyU0dm+6O2IrT5tAFrbHLso=023551024" From: To: Contact: Call-ID: Authorization: Digest username="[email protected]", realm="registrar.home1.net",

nonce=base64(RAND + AUTN + server specific data), algorithm=AKAv1-MD5, uri="sip:registrar.home1.net", response="6629fae49393a05397450978507c4ef1", integrity-protected="yes"

CSeq: Supported: Content-Length:


REGISTER 请求 (I-CSCF to S-CSCF) ：


pcscf1.visited1.net;branch=z9hG4bK240f34.1, SIP/2.0/UDP [5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7

Max-Forwards: 68 P-Access-Network-Info: Path: Require: P-Visited-Network-ID: P-Charging-Vector: From: To: Contact: Call-ID: Authorization: CSeq: Supported: Content-Length:


P-Charging-Vector:S-CSCF 保存 ICID 参数的内容，用于计费。

200 OK 响应 (S-CSCF to I-CSCF)


33

SIP/2.0 200 OK Via: SIP/2.0/UDP icscf1_p.home1.net;branch=z9hG4bK351g45.1, SIP/2.0/UDP


Path: <sip:[email protected];lr> Service-Route: <sip:[email protected];lr> From: To: Call-ID: Contact: <sip:[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp>;expires=600000 CSeq: Date: Wed, 11 July 2001 08:49:37 GMT P-Associated-URI: <sip:[email protected]>, <sip:[email protected]>,

<sip:[email protected];user=phone> Content-Length:

Service-Route:S-CSCF 插入 Service-Route 头域，用于区分请求是从主叫方还是从被叫方发出的。

头域值为 S-CSCF 的 URI。

200 OK 响应(I-CSCF to P-CSCF)

SIP/2.0 200 OK Via: SIP/2.0/UDP pcscf1.visited1.net;branch=z9hG4bK240f34.1, SIP/2.0/UDP

[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 Path: Service-Route: From: To: Call-ID: Contact: CSeq: Date: P-Associated-URI: Content-Length:

6.5.1.2 UE 发起的重注册

UE P-CSCF(pcscf1)


S-CSCF(scscf1)

HSS


1. REGISTER

2. DNS: DNS-Q

3. REGISTER

5. REGISTER

7. 200 OK

8. 200 OK9. 200 OK


6. Update registration timer


34

图16 UE 发起的重注册流程

REGISTER 请求(P-CSCF to I-CSCF)


[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 P-Access-Network-Info: Max-Forwards: 69 Path: <sip:[email protected];lr> Require: path P-Visited-Network-ID: "Visited Network Number 1" P-Charging-Vector: icid-value="AyretyU0dm+6O2IrT5tAFrbHLso=023551024" From: To: Contact: Call-ID: Authorization: Digest username="[email protected]", realm="registrar.home1.net",

nonce=base64(RAND + AUTN + server specific data), algorithm=AKAv1-MD5, uri="sip:registrar.home1.net", response="6629fae49393a05397450978507c4ef1", integrity-protected="yes"

CSeq: Supported: Content-Length:


Require:此头域能保证接收端能正确处理 Path 头域，如果接收端不支持 Path 头域，就会返回 420

消息并携带 Unsupported 头域，指示不支持 Path 头域。这个响应表明路由表配置错误以及请求被路由到

了 IMS 域外。 P-Visited-Network-ID:P-CSCF 所在归属网络的网络标识。


REGISTER 请求 (I-CSCF to S-CSCF)



P-Access-Network-Info: Max-Forwards: 68 Path: Require: P-Visited-Network-ID: P-Charging-Vector: From: To: Contact: Call-ID: Authorization: CSeq: Supported: Content-Length:



P-Visited-Network-ID:P-CSCF 所在归属网络的网络标识。

200 OK response (S-CSCF to I-CSCF)

SIP/2.0 200 OK Via: SIP/2.0/UDP icscf1_p.home1.net;branch=z9hG4bK351g45.1, SIP/2.0/UDP


Path: Service-Route: <sip:[email protected];lr>


35

From: To: Call-ID: Contact: <sip:[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp>;expires=600000 CSeq: Date: Wed, 11 July 2001 08:49:37 GMT P-Associated-URI: <sip:[email protected]>, <sip:[email protected]>,

<sip:[email protected];user=phone> Content-Length:

Service-Route:S-CSCF 插入 Service-Route 头域，用于区分请求是从主叫方还是从被叫方发出的。

头域值为 S-CSCF 的 URI

200 OK 响应(I-CSCF to P-CSCF)


[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 Path: Service-Route: From: To: Call-ID: Contact: CSeq: Date: P-Associated-URI: Content-Length:

6.5.1.3 UE 订阅用户注册状态事件

UE I-CSCF(icscf1_p)

S-CSCF(scscf1)


P-CSCF(pcscf1)

DNS

4. 202 (OK)

1. SUBSCRIBE

2. SUBSCRIBE

3. 200 (OK)

6. NOTIFY

5. NOTIFY

7. 200 (OK)

8. 200 (OK)

图17 UE 订阅用户注册状态事件流程

SUBSCRIBE 请求(P-CSCF to S-CSCF)

SUBSCRIBE sip:[email protected] SIP/2.0 Via: SIP/2.0/UDP pcscf1.visited1.net;branch=z9hG4bK240f34.1, SIP/2.0/UDP

[5555::aaa:bbb:ccc:ddd].1357;comp=sigcomp;branch=z9hG4bKnashds7 Max-Forwards: 69 Route: <sip:[email protected];lr> Record-Route: <sip:pcscf1.home1.net;lr>


36

P-Asserted-Identity: "John Doe" <sip:[email protected]> P-Access-Network-Info: P-Charging-Vector: icid-value="AyretyU0dm+6O2IrT5tAFrbHLso=023551024" Privacy: From: To: Call-ID: CSeq: Event: Expires: Accept: Contact: Content-Length:

P-Asserted-Identity:P-CSCF 插入 P-Asserted-Identity 头域，值为 SIP URI 的值，并删除

P-Preferred-Identity 头域。



200 (OK) response (S-CSCF to P-CSCF)


[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 Record-Route: <sip:pcscf1.home1.net;lr> P-Asserted-Identity: <sip:scscf1.home1.net> Privacy: none From: To: <sip:[email protected]>;tag=151170 Call-ID: CSeq: Expires: Contact: <sip:scscf1.home1.net> Content-Length:

Expires:如果 SUBSCIRBE 消息中 Expires 的值与 REGISTER 消息中的对应值不同，则 200 OK 中的

Expires 设置为 REGISTER 中 Expires 的值。

NOTIFY request (S-CSCF to P-CSCF)

NOTIFY sip:[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp SIP/2.0 Via: SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1 Max-Forwards: 70 Route: <sip:pcscf1.home1.net;lr> From: <sip:[email protected]>;tag=31415 To: <sip:[email protected]>;tag=151170 Call-ID: CSeq: 42 NOTIFY Subscription-State: active;expires=600000 Event: reg Content-Type: application/reginfo+xml Contact: <sip:scscf1.home1.net> Content-Length: (...) <?xml version="1.0"?> <reginfo xmlns="urn:ietf:params:xml:ns:reginfo" version="1" state="full"> <registration aor="sip:[email protected]" id="a7" state="active"> <contact id="76" state="active" event="registered"> <uri>sip:[5555::aaa:bbb:ccc:ddd]</uri> </contact> </registration> <registration aor="sip:[email protected]" id="a8" state="active"> <contact id="77" state="active" event="created"> <uri>sip:[5555::aaa:bbb:ccc:ddd]</uri> </contact> </registration>


37

<registration aor="tel:+358504821437" id="a9" state="active"> <contact id="78" state="active" event="created"> <uri>sip:[5555::aaa:bbb:ccc:ddd]</uri> </contact> </registration> </reginfo>

From:与 To 头域值相同，在队 SUBSCRIBE 的 200 OK 响应中填充。

Content-Type:如果 SUBSCRIBE 请求中有 Accept 头域，就设置为 Accept 头域的值，否则就设置为

"application/reginfo+xml"。

200 (OK) response (P-CSCF to S-CSCF)

SIP/2.0 200 OK Via: SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1 P-Access-Network-Info: From: To: Call-ID: CSeq: Content-Length:

6.5.1.4 P-CSCF 订阅注册状态事件

UE I-CSCF(icscf1_p)

S-CSCF(scscf1)


P-CSCF(pcscf1)

DNS

2. SUBSCRIBE

5. 200 (OK)

7. NOTIFY

8. 200 (OK)

1. DNS: DNS-Q

HSS

3. Cx: User location query

4. SUBSCRIBE

6. 200 (OK)

图18 P-CSCF 订阅注册状态事件流程

SUBSCRIBE 请求(P-CSCF to I-CSCF)

SUBSCRIBE sip:[email protected] SIP/2.0 Via: SIP/2.0/UDP pcscf1.visited1.net;branch=z9hG4bK240f34.1 Max-Forwards: 70 P-Asserted-Identity: <sip:pcscf1.visited1.net> Privacy: none From: <sip:pcscf1.visited1.net>;tag=31415 To: <sip:[email protected]> Call-ID: dre36d2v32gnlgiiomm72445 CSeq: 61 SUBSCRIBE Event: reg Expires: 600000


38

Accept: application/reginfo+xml Contact: <sip:pcscf1.visited1.net> Content-Length: 0

From:标识 P-CSCF 的 SIP URI。

Contact:NOTIFY 请求发送的地址。

Event:值设为‘reg'，表明为注册事件包。

Accept:值设为"application/reginfo+xml"。

SUBSCRIBE 请求(I-CSCF to S-CSCF)

SUBSCRIBE sip:[email protected] SIP/2.0 Via: SIP/2.0/UDP icscf1_p.home1.net;branch=z9hG4bK871y12.1, SIP/2.0/UDP

pcscf1.visited1.net;branch=z9hG4bK240f34.1 Max-Forwards: 69 Route: <sip:scscf1.home1.net;lr> P-Asserted-Identity: Privacy: From: To: Call-ID: CSeq: Event: Expires: Accept: Contact: Content-Length:

200 (OK) 响应 (S-CSCF to I-CSCF)

SIP/2.0 200 OK Via: SIP/2.0/UDP icscf1_s.home1.net;branch=z9hG4bK871y12.1, SIP/2.0/UDP

pcscf1.visited1.net;branch=z9hG4bK240f34.1 P-Asserted-Identity: <sip:scscf1.home1.net> Privacy: From: To: <sip:[email protected]>;tag=151170 Call-ID: CSeq: Contact: <sip:scscf1.home1.net> Expires: Content-Length:

Expires:如果 SUBSCIRBE 消息中 Expires 的值与 REGISTER 消息中的对应值不同，则 200 OK 中的

Expires 设置为 REGISTER 中 Expires 的值。

200 (OK) 响应(I-CSCF to P-CSCF)

SIP/2.0 200 OK Via: SIP/2.0/UDP pcscf1.visited1.net;branch=z9hG4bK240f34.1 P-Asserted-Identity: Privacy: From: To: Call-ID: CSeq: Contact: Expires: Content-Length:

NOTIFY 请求(S-CSCF to P-CSCF)

NOTIFY sip:pcscf1.visited1.net SIP/2.0 Via: SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1 Max-Forwards: 70 From: <sip:[email protected]>;tag=151170


39

To: <sip:[email protected]>;tag=31415 Call-ID: dre36d2v32gnlgiiomm72445 CSeq: 42 NOTIFY Subscription-State: active;expires=600000 Event: reg Content-Type: application/reginfo+xml Contact: <sip:scscf1.home1.net> Content-Length: (...) <?xml version="1.0"?> <reginfo xmlns="urn:ietf:params:xml:ns:reginfo" version="1" state="full"> <registration aor="sip:[email protected]" id="a7" state="active"> <contact id="76" state="active" event="registered"> <uri>sip:[5555::aaa:bbb:ccc:ddd]</uri> </contact> </registration> <registration aor="sip:[email protected]" id="a8" state="active"> <contact id="77" state="active" event="created"> <uri>sip:[5555::aaa:bbb:ccc:ddd]</uri> </contact> </registration> <registration aor="tel:+358504821437" id="a9" state="active"> <contact id="78" state="active" event="created"> <uri>sip:[5555::aaa:bbb:ccc:ddd]</uri> </contact> </registration> </reginfo>

From:与 To 头域值相同，在队 SUBSCRIBE 的 200 OK 响应中填充。



200 (OK) 响应(P-CSCF to S-CSCF)

SIP/2.0 200 OK Via: SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1 From: To: Call-ID: CSeq: Content-Type: Content-Length: 0

6.5.1.5 网络发起的注销事件 6.5.1.5.1 S-CSCF 发起的网络注销


40

UE I-CSCF(icscf1_p)

S-CSCF(scscf1)


P-CSCF(pcscf1)

DNS

1. SUBSCRIBE

2. NOTIFY

5. 200 (OK)

HSS

1. event occurs

3. NOTIFY

4. 200 (OK)

6. NOTIFY

7. 200 (OK)

8. S-CSCF deregistration notification

图19 S-CSCF 发起的网络注销流程

NOTIFY 请求 (S-CSCF to P-CSCF)

NOTIFY sip:[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp SIP/2.0 Via: SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1 Max-Forwards: 70 Route: <sip:pcscf1.visited1.net;lr> From: <sip:[email protected]>;tag=151170 To: <sip:[email protected]>;tag=31415 Call-ID: b89rjhnedlrfjflslj40a222 CSeq: 43 NOTIFY Subscription-State: terminated Event: reg Content-Type: application/reginfo+xml Contact: sip:scscf1.home1.net Content-Length: (...) <?xml version="1.0"?> <reginfo xmlns="urn:ietf:params:xml:ns:reginfo" version="1" state="full"> <registration aor="sip:[email protected]" id="as9" state="terminated"> <contact id="76" state="terminated" event="deactivated"> <uri>sip:[5555::aaa:bbb:ccc:ddd]</uri> </contact> </registration> <registration aor="sip:[email protected]" id="as10" state="terminated"> <contact id="77" state="terminated" event="deactivated"> <uri>sip:[5555::aaa:bbb:ccc:ddd]</uri> </contact> </registration> <registration aor="tel:+358504821437" id="as11" state="terminated"> <contact id="78" state="terminated" event="deactivated"> <uri>sip:[5555::aaa:bbb:ccc:ddd]</uri> </contact> </registration> </reginfo>


41

200 (OK) 响应 (P-CSCF to S-CSCF)


P-Access-Network-Info: 包含从 UE 携带的信息。


NOTIFY sip:pcscf1.visited1.net SIP/2.0 Via: SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1 Max-Forwards: 70 From: <sip:[email protected]>;tag=151170 To: <sip:pcscf1.visited1.net>;tag=31415 Call-ID: dre36d2v32gnlgiiomm72445 CSeq: 43 NOTIFY Subscription-State: terminated Event: reg Content-Type: application/reginfo+xml Contact: sip:scscf1.home1.net Content-Length: (...) <?xml version="1.0"?> <reginfo xmlns="urn:ietf:params:xml:ns:reginfo" version="1" state="full"> <registration aor="sip:[email protected]" id="as9" state="terminated"> <contact id="76" state="terminated" event="deactivated"> <uri>sip:[5555::aaa:bbb:ccc:ddd]</uri> </contact> </registration> <registration aor="sip:[email protected]" id="as10" state="terminated"> <contact id="77" state="terminated" event="deactivated"> <uri>sip:[5555::aaa:bbb:ccc:ddd]</uri> </contact> </registration> <registration aor="tel:+358504821437" id="as11" state="terminated"> <contact id="78" state="terminated" event="deactivated"> <uri>sip:[5555::aaa:bbb:ccc:ddd]</uri> </contact> </registration> </reginfo>


SIP/2.0 200 OK Via: SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1 From: To: Call-ID: CSeq: Content-Length: 0

6.5.1.5.2 HSS 发起的网络注销


42

UE P-CSCF(pcscf1)

DNS I-CSCF(icscf1_p)

S-CSCF(scscf1)

HSS


2. Cx: Deregister

1. Event occurs

3. NOTIFY4. NOTIFY

5. 200 (OK)6. 200 (OK)

7. NOTIFY

8. 200 (OK)9. Cx: Deregister

response

图20 HSS 发起的网络注销流程图


NOTIFY sip:[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp SIP/2.0 Via: SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1 Max-Forwards: 70 Route: <sip:pcscf1.visited1.net;lr> From: <sip:[email protected]>;tag=151170 To: <sip:[email protected]>;tag=31415 Call-ID: b89rjhnedlrfjflslj40a222 CSeq: 43 NOTIFY Subscription-State: terminated Event: reg Content-Type: application/reginfo+xml Contact: <sip:scscf1.home1.net> Content-Length: (...) <?xml version="1.0"?> <reginfo xmlns="urn:ietf:params:xml:ns:reginfo" version="1" state="full"> <registration aor="sip:[email protected]" id="as9" state="terminated"> <contact id="76" state="terminated" event="deactivated"> <uri>sip:[5555::aaa:bbb:ccc:ddd]</uri> </contact> </registration> <registration aor="sip:[email protected]" id="as10" state="terminated"> <contact id="77" state="terminated" event="deactivated">


43

<uri>sip:[5555::aaa:bbb:ccc:ddd]</uri> </contact> </registration> <registration aor="tel:+358504821437" id="as11" state="terminated"> <contact id="78" state="terminated" event="deactivated"> <uri>sip:[5555::aaa:bbb:ccc:ddd]</uri> </contact> </registration> </reginfo>





NOTIFY sip:pcscf1.visited1.net SIP/2.0 Via: SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1 Max-Forwards: 70 From: <sip:[email protected]>;tag=151170 To: <sip:pcscf1.visited1.net>;tag=31415 Call-ID: dre36d2v32gnlgiiomm72445 CSeq: 43 NOTIFY Subscription-State: terminated Event: reg Contact: <sip:scscf1.home1.net> Content-Type: application/reginfo+xml Content-Length: (...) <?xml version="1.0"?> <reginfo xmlns="urn:ietf:params:xml:ns:reginfo" version="1" state="full"> <registration aor="sip:[email protected]" id="as9" state="terminated"> <contact id="76" state="terminated" event="deactivated"> <uri>sip:[5555::aaa:bbb:ccc:ddd]</uri> </contact> </registration> <registration aor="sip:[email protected]" id="as10" state="terminated"> <contact id="77" state="terminated" event="deactivated"> <uri>sip:[5555::aaa:bbb:ccc:ddd]</uri> </contact> </registration> <registration aor="tel:+358504821437" id="as11" state="terminated"> <contact id="78" state="terminated" event="deactivated"> <uri>sip:[5555::aaa:bbb:ccc:ddd]</uri> </contact> </registration> </reginfo>


SIP/2.0 200 OK Via: SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1 From: To:


44

Call-ID: CSeq: Content-Length: 0

6.5.1.5.3 网络发起的注销（UE 漫游向新网络注册，假设前一个注册没有终止）

UE P-CSCF(pcscf2)


S-CSCF(scscf1)

HSS

NEW Visited Network (visited2.net) Home Network (home1.net)

1. REGISTER

2. DNS: DNS-Q

3. REGISTER

5. REGISTER

7. 200 (OK)

10. 200 (OK)

11. 200 (OK)

Old Visited Network

(visited1.net)

8. NOTIFY

P-CSCF(pcscf1)

9.200 (OK)


6. Cx: S-CSCF registration notification

图21 网络发起的注销

NOTIFY 请求 (S-CSCF to Old P-CSCF)

NOTIFY sip:pcscf1.visited1.net SIP/2.0 Via: SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1 Max-Forwards: 70 From: <sip:[email protected]>;tag=151170 To: <sip:pcscf1.visited1.net>;tag=31415 Call-ID: dre36d2v32gnlgiiomm72445 CSeq: 43 NOTIFY Subscription-State: terminated Event: reg Content-Type: application/reginfo+xml Contact: <sip:scscf1.home1.net> Content-Length: (...) <?xml version="1.0"?> <reginfo xmlns="urn:ietf:params:xml:ns:reginfo" version="1" state="full"> <registration aor="sip:[email protected]" id="as9"


45

state="terminated"> <contact id="76" state="terminated" event="deactivated"> <uri>sip:[5555::aaa:bbb:ccc:ddd]</uri> </contact> </registration> <registration aor="sip:[email protected]" id="as10" state="terminated"> <contact id="77" state="terminated" event="deactivated"> <uri>sip:[5555::aaa:bbb:ccc:ddd]</uri> </contact> </registration> <registration aor="tel:+358504821437" id="as11" state="terminated"> <contact id="78" state="terminated" event="deactivated"> <uri>sip:[5555::aaa:bbb:ccc:ddd]</uri> </contact> </registration> </reginfo>

200 (OK) 响应 (Old P-CSCF to S-CSCF)

SIP/2.0 200 OK Via: SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1 From: To: Call-ID: CSeq: Content-Length: 0

6.5.1.6 网络发起的重认证

UE I-CSCF(icscf1_p)

S-CSCF(scscf1)


P-CSCF(pcscf1)

DNS

3. SIP NOTIFY

2. SIP NOTIFY

4. SIP 200 (OK)

5. SIP 200 (OK)

1.Network-initiated re-authentication

6. initiate Re-authentication

图22 网络发起的重认证流程


NOTIFY sip:[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp SIP/2.0 Via: SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1 Max-Forwards: 70 Route: <sip:pcscf1.visited1.net;lr> From: <sip:[email protected]>;tag=31415 To: <sip:[email protected]>;tag=151170 Call-ID: b89rjhnedlrfjflslj40a222 CSeq: 43 NOTIFY Subscription-State: active;expires=3200 Event: reg Content-Type: application/reginfo+xml


46

Contact: sip:scscf1.home1.net Content-Length: (...) <?xml version="1.0"?> <reginfo xmlns="urn:ietf:params:xml:ns:reginfo" version="1" state="partial"> <registration aor="sip:[email protected]" id="as9" state="active"> <contact id="76" state="active" event="shortened" expires="600"> <uri>sip:[5555::aaa:bbb:ccc:ddd]</uri> </contact> </registration> </reginfo>

From:与 To 头域值相同，在对 SUBSCRIBE 的 200 OK 响应中填充。



200 OK 响应 (P-CSCF to S-CSCF)



6.5.1.7 异常流程

Mw接口的注册异常流程主要有三种情况：

6.5.1.7.1 重注册失败


47

UE I-CSCF(icscf1_p)

S-CSCF(scscf1)


P-CSCF(pcscf1)

DNS

5. REGISTER

HSSS-CSCF(scscf2)

6. Timeout of Re-Register


1. REGISTER

15. REGISTER

2. DNS: DNS-Q

15. DNS: DNS-Q

3. REGISTER

17. REGISTER



8. REGISTER

19. REGISTER

11. 401 (Unauthorized)



9. Cx: Authentication

10. Autentication Vector Selection

20. Authentication


22. 200 (OK)

23. 200 (OK)

24. 200 (OK)

14. Generation of Response and session keys


48

图23 重注册失败




P-Access-Network-Info: Max-Forwards: 68 Path: <sip:icscf1_p.home1.net;lr>, <sip:[email protected];lr> Require: path P-Visited-Network-ID: "Visited Network Number 1" From: <sip:[email protected]>;tag=4fa3 To: <sip:[email protected]> Contact: <sip:[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp>;expires=600000 Call-ID: apb03a0s09dkjdfglkj49111 Authorization: Digest username="[email protected]", realm="registrar.home1.net",

nonce=base64(RAND + AUTN + server specific data), algorithm=AKAv1-MD5, uri="sip:registar.home1.net", response="0a1b04c89e54f09ab45e84d30e29f83a", integrity-protected="yes"

CSeq: 10 REGISTER Supported: path Content-Length: 0

REGISTER 请求(I-CSCF to S-CSCF)

REGISTER sip:scscf2.home1.net SIP/2.0 Via: P-Access-Network-Info: Max-Forwards: 68 Path: Require: P-Visited-Network-ID: From: To: Contact: Call-ID: Authorization: CSeq: Supported: Content-Length:




Max-Forwards: 68 P-Access-Network-Info: Path: <sip:icscf1_p.home1.net;lr>, <sip:[email protected];lr> Require: P-Visited-Network-ID: From: To: Contact: Call-ID: Authorization: CSeq: Supported: Content-Length:

Path:S-CSCF 保存 Path 头域，用于会话路由。

6.5.1.7.2 用户未注册，用户不允许漫游/用户未知


49

UEI-CSCF S-CSCF


P-CSCF DNS

1. REGISTER

HSS

3. REGISTER

2. DNS: DNS-Q

4. Cx: User Registration Status Query

5. Roaming not allowed / user

unknown

6. 403 (Forbidden)

7. 403 (Forbidden)

图24 用户未注册，用户不允许漫游/用户未知

由于用户不允许漫游和用户未知的情形下，信令流程是相同的，只有 I-CSCF 对两种情况的处理有

所不同，当 I-CSCF 发现用户不允许漫游和用户未知时，I-CSCF 将发送 403 Forbidden 消息给 UE，在

403 消息中，I-CSCF 插入 warning 头，warning 头的内容包括 I-CSCF 所在的域名和错误原因和错误代

码 399。

I-CSCF 发送给 P-CSCF 的 403 Forbidden 消息示例如下：

SIP/2.0 403 Forbidden Via: SIP/2.0/UDP pcscf1.visited1.net;branch=z9hG4bK240f34.1, SIP/2.0/UDP

[5555::aaa:bbb:ccc:ddd];comp=sigcomp;branch=z9hG4bKnashds7 Warning: 399 home1.net "Roaming not allowed from this network" From: To: Call-ID: Cseq: Content-Length: 0

6.5.1.7.3 用户注册失败-用户鉴权失败


50

UE P-CSCF(pcscf1)


S-CSCF(scscf1)

HSS


1. REGISTER

2. DNS: DNS-Q

3. REGISTER

5. REGISTER



6. Cx: Authentication




12. REGISTER

13. DNS: DNS-Q

14. REGISTER

16. REGISTER


7. Autentication Vector Selection

11. Generation of Response and

session keys

17. Authentication

19. 403 (Forbidden)

20. 403 (Forbidden)

21.403 (Forbidden)

图25 用户注册失败流程


51

第 20 步：S-CSCF 向 I-CSCF 发送 403（Forbidden）消息指示 I-CSCF 鉴权失败，响应中没有包含安

全参数，S-CSCF在403中插入warning头域指示拒绝用户注册请求的原因，Warning头域内容包括S-CSCF

所在的域名和错误原因和错误代码 399。

S-CSCF 向 I-CSCF 发送的 403（Forbidden）消息示例如下：

SIP/2.0 403 Forbidden Via: SIP/2.0/UDP icscf1_p.home1.net;branch=z9hG4bK351g45.1, SIP/2.0/UDP


Warning: 399 home1.net "Authentication failed" From: <sip:[email protected]>;tag=4fa3 To: <sip:[email protected]>; tag=5ef4 Call-ID: apb03a0s09dkjdfglkj49111 CSeq: 3 REGISTER Content-Length: 0

I-CSCF 转发 S-CSCF 发来的 403（Forbidden）消息给 P-CSCF。403（Forbidden）消息示例如下：

SIP/2.0 403 Forbidden Via: SIP/2.0/UDP pcscf1.visited1.net;branch=z9hG4bK240f34.1, SIP/2.0/UDP

[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 Warning: 399 home1.net "Authentication failed" From: To: Call-ID: CSeq: Content-Length:

6.5.2 会话消息 6.5.2.1 MO 流程 6.5.2.1.1 IMS 用户主叫（漫游）


52

1. INVITE

27. 180 (Ringing)

3. INVITE

UE#1 P-CSCF S-CSCF

8. 183 (Session Progress)

11. 183 (Session Progress)12. PRACK

16. 200 (OK)

25. 180 (Ringing)

28. PRACK

31. 200 (OK)

35. 200 (OK)

37. 200 (OK)

19. UPDATE

22. 200 (OK)

38. ACK

6. INVITE

26. 180 (Ringing)


34. 200 (OK)


5. Evaluation of InitialFilter Criterias

2. 100 (Trying)

4. 100 (Trying)

7. 100 (Trying)

14. PRACK 15. PRACK

17. 200 (OK)18. 200 (OK)

20. UPDATE 21. UPDATE

23. 200 (OK)24. 200 (OK)

29. PRACK 30. PRACK

32. 200 (OK)33. 200 (OK)

39. ACK40. ACK

Visited Network Home Network

10. Authorize QoS resources

36. Approval of QoS commit

图26 IMS 域用户主叫（漫游）

INVITE (P-CSCF to S-CSCF)

INVITE tel:+1-212-555-2222 SIP/2.0 Via: SIP/2.0/UDP pcscf1.visited1.net;branch=z9hG4bK240f34.1, SIP/2.0/UDP

[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 Max-Forwards: 69 Route: <sip:scscf1.home1.net;lr> Record-Route: <sip:pcscf1.visited1.net;lr> P-Asserted-Identity: "John Doe" <sip:[email protected]> P-Access-Network-Info: P-Charging-Vector: icid-value="AyretyU0dm+6O2IrT5tAFrbHLso=023551024" Privacy: From: To: Call-ID: Cseq: Require: precondition Supported: Contact: Allow: Content-Type: Content-Length: (…) v= o= s= c= t= m= b= a= a=


53

a= a= a= a= a= m= b= a= a= a= a= a= a= a= a=




100 Trying (S-CSCF to P-CSCF)

SIP/2.0 100 Trying Via: SIP/2.0/UDP pcscf1.visited1.net;branch=z9hG4bK240f34.1, SIP/2.0/UDP

[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 From: To: Call-ID: CSeq: Content-Length: 0

183 Session Progress (S-CSCF to P-CSCF)

SIP/2.0 183 Session Progress Via: SIP/2.0/UDP pcscf1.visited1.net;branch=z9hG4bK240f34.1, SIP/2.0/UDP

[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 Record-Route: P-Asserted-Identity: P-Charging-Vector: icid-value="AyretyU0dm+6O2IrT5tAFrbHLso=023551024" Privacy: From: To: Call-ID: CSeq: Require: Contact: Allow: RSeq: Content-Type: Content-Length: v= o= s= c= t= m= b= a= a= a= a= a= a= a= a= m=


54

b= a= a= a= a= a= a= a= a= a=

PRACK (P-CSCF to S-CSCF)

PRACK sip:[5555::eee:fff:aaa:bbb]:8805;comp=sigcomp SIP/2.0 Via: SIP/2.0/UDP pcscf1.visited1.net;branch=z9hG4bK240f34.1, SIP/2.0/UDP

[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 Max-Forwards: 69 P-Access-Network-Info: Route: <sip:scscf1.home1.net;lr>, <sip:scscf2.home2.net;lr>, <sip:pcscf2.visited2.net;lr> From: To: Call-ID: Cseq: Require: precondition RAck: Content-Type: Content-Length: v= o= s= c= t= m= b= a= a= a= a= a= a= m= b= a= a= a= a= a= a= a= a=

200 OK (S-CSCF to P-CSCF)


[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 From: To: Call-ID: CSeq: Content-Type: Content-Length: v= o= s=


55

c= t= m= b= a= a= a= a= a= a= a= m= b= a= a= a= a= a= a= a= a= a=

UPDATE (P-CSCF to S-CSCF)

UPDATE sip:[5555::eee:fff:aaa:bbb]:8805;comp=sigcomp SIP/2.0 Via: SIP/2.0/UDP pcscf1.visited1.net;branch=z9hG4bK240f34.1, SIP/2.0/UDP

[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 Max-Forwards: 69 P-Access-Network-Info: P-Charging-Vector: icid-value="AyretyU0dm+6O2IrT5tAFrbHLso=023551024";

ggsn=[5555::4b4:3c3:2d2:1e1]; auth-token=2A96B3AF30D1; pdp-info="pdp-item=1; pdp-sig=no; gcid= A93D238CAF; flow-id=({1,1},{1,2}), pdp-item=2; pdp-sig=no; gcid=F312D5E3BC; flow-id=({2,1},{2,2})"

Route: <sip:scscf1.home1.net;lr>, <sip:scscf2.home2.net;lr>, <sip:pcscf2.visited2.net;lr> From: To: Call-ID: Cseq: Content-Type: Content-Length: v= o= s= c= t= m= b= a= a= a= a= a= a= m= b= a= a= a= a= a= a= a= a=

P-Charging-Vector:P-CSCF 在此头域中增加 GPRS 访问网络的信息，这些信息由 S-CSCF 保存和删

除。


56



[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 From: To: Call-ID: CSeq: Content-Type: Content-Length: v= o= s= c= t= m= b= a= a= a= a= a= a= m= b= a= a= a= a= a= a= a= a=

180 Ringing (S-CSCF to P-CSCF)

SIP/2.0 180 Ringing Via: SIP/2.0/UDP pcscf1.visited1.net;branch=z9hG4bK240f34.1, SIP/2.0/UDP

[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 Record-Route: From: To: Call-ID: CSeq: Require: Contact: Allow: RSeq: Content-Length:


PRACK sip:[5555::eee:fff:aaa:bbb]:8805;comp=sigcomp SIP/2.0 Via: SIP/2.0/UDP pcscf1.visited1.net;branch=z9hG4bK240f34.1, SIP/2.0/UDP

[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 Max-Forwards: 69 P-Access-Network-Info: Route: <sip:scscf1.home1.net;lr>, <sip:scscf2.home2.net;lr>, <sip:pcscf2.visited2.net;lr> From: To: Call-ID: Cseq: RAck: Content-Length:


57



[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 From: To: Call-ID: CSeq: Content-Length:



[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 Record-Route: From: To: Call-ID: CSeq: Contact: Content-Length:

ACK (P-CSCF to S-CSCF)

ACK sip:[5555::eee:fff:aaa:bbb]:8805;comp=sigcomp SIP/2.0 Via: SIP/2.0/UDP pcscf1.visited1.net;branch=z9hG4bK240f34.1, SIP/2.0/UDP

[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 Max-Forwards: 69 Route: <sip:scscf1.home1.net;lr>, <sip:scscf2.home2.net;lr>, <sip:pcscf2.visited2.net;lr> From: To: Call-ID: Cseq: Content-Length:

6.5.2.1.2 被叫侧失败（漫游）


58

1. INVITE

27. 180 (Ringing)

3. INVITE

UE#1 P-CSCF S-CSCF



12. PRACK

16. 200 (OK)

25. 180 (Ringing)

28. PRACK

31. 200 (OK)

36. xxx (Error)

39. xxx (Error)

19. UPDATE

23. 200 (OK)

40. ACK

6. INVITE

26. 180 (Ringing)

9.183 (SessionProgress)

34. xxx (Error)



10. Authorize QoS Resources

2. 100 (Trying)

4. 100 (Trying)

7. 100 (Trying)

14. PRACK15. PRACK

17. 200 (OK)18. 200 (OK)

21. UPDATE22. UPDATE

24. 200 (OK)25. 200 (OK)

29. PRACK30. PRACK

32. 200 (OK)33. 200 (OK)

37. ACK

35. ACK


38. Revoke QoS Resources

图27 被叫侧失败流程（漫游）

xxx Error (S-CSCF to P-CSCF)

xxx Error 消息可能是"486 (Busy Here)", "403 (Forbidden)", "480 (Temporarily Unavailable)"

等消息。下图为 486（Busy here）示例：

SIP/2.0 486 Busy Here Via: SIP/2.0/UDP pcscf1.visited1.net;branch=z9hG4bK240f34.1, SIP/2.0/UDP

[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 From: To: Call-ID: CSeq: Retry-After: 3600 Content-Length: 0


ACK tel:+1-212-555-2222 SIP/2.0 Via: SIP/2.0/UDP pcscf1.visited1.net;branch=z9hG4bK240f34.1 Max-Forwards: 70 Route: <sip:scscf1.home1.net;lr> From: To: Call-ID: CSeq: 127 ACK Content-Length: 0


59

6.5.2.1.3 会话放弃或者资源失败（漫游）

1. INVITE

27. 180 (Ringing)

3. INVITE

UE#1 P-CSCF S-CSCF



12. PRACK

16. 200 (OK)

25. 180 (Ringing)

28. PRACK

31. 200 (OK)

38. 200 (OK)

35. 200 (OK)

19. UPDATE

22. 200 (OK)

34. CANCEL

6. INVITE

26. 180 (Ringing)

9.183 (SessionProgress)

40. 200 (OK)




2. 100 (Trying)

4. 100 (Trying)

7. 100 (Trying)

14. PRACK15. PRACK

17. 200 (OK)18. 200 (OK)


23. 200 (OK)24. 200 (OK)

29. PRACK30. PRACK

32. 200 (OK)33. 200 (OK)

37. CANCEL

39. CANCEL



41. 487 (RequestTeminated)

43. 487 (RequestTerminated)


42. ACK

44. ACK

46. ACK

图28 会话放弃或者资源失败（漫游）

CANCEL (P-CSCF to S-CSCF)

CANCEL tel:+1-212-555-2222 SIP/2.0 Via: SIP/2.0/UDP pcscf1.visited1.net;branch=z9hG4bK240f34.1 Max-Forwards: 70 Route: <sip:scscf1.home1.net;lr> From: To: Call-ID: Cseq: Content-Length:


SIP/2.0 200 OK Via: SIP/2.0/UDP pcscf1.visited1.net;branch=z9hG4bK240f34.1 From: To: Call-ID: CSeq: Content-Length: 0


60

487 请求终止 (S-CSCF to P-CSCF)

SIP/2.0 487 Request Terminated Via: SIP/2.0/UDP pcscf1.visited1.net;branch=z9hG4bK240f34.1, SIP/2.0/UDP



ACK tel:+1-212-555-2222 SIP/2.0 Via: SIP/2.0/UDP pcscf1.visited1.net;branch=z9hG4bK240f34.1 Max-Forwards: 70 Route: <sip:scscf1.home1.net;lr> From: To: Call-ID: CSeq: 127 ACK Content-Length: 0

6.5.2.1.4 IMS 用户发起呼叫（位于归属网络）

1. INVITE

27. 180 (Ringing)

3. INVITE

UE P-CSCF S-CSCF



12. PRACK

18. 200 (OK)

26. 180 (Ringing)

28. PRACK

33. 200 (OK)

35. 200 (OK)

37. 200 (OK)

19. UPDATE

22. 200 (OK)

38. ACK

5. Evaluation of InitialFilter Criteria

6. INVITE

34. 200 (OK)

Home Network

25. 180 (Ringing)



2. 100 (Trying)

4. 100 (Trying)

7. 100 (Trying)

14. PRACK15. PRACK


24. 200 (OK)23. 200 (OK)

17. 200 (OK)16. 200 (OK)

29. PRACK 30. PRACK

32. 200 (OK) 31. 200 (OK)

39. ACK40. ACK


36. Approval of QoSCommit

图29 IMS 域用户发起呼叫（位于归属网络）


61

INVITE (P-CSCF to S-CSCF)

INVITE tel:+1-212-555-2222 SIP/2.0 Via: SIP/2.0/UDP pcscf1.home1.net;branch=z9hG4bK431h23.1, SIP/2.0/UDP

[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 Max-Forwards: 69 Record-Route: <sip:pcscf1.home1.net;lr> Route: <sip:scscf1.home1.net;lr> P-Asserted-Identity: "John Doe" <tel:+1-212-555-1111> P-Access-Network-Info: P-Charging-Vector: icid-value="AyretyU0dm+6O2IrT5tAFrbHLso=023551024" Privacy: From: To: Call-ID: Cseq: Require: precondition Supported: Contact: Allow: Content-Type: Content-Length: (…) v= o= s= c= t= m= b= a= a= a= a= a= a= a= m= b= a= a= a= a= a= a= a= a=


P-Preferred-Identity 头域。



100 Trying (S-CSCF to P-CSCF)

SIP/2.0 100 Trying Via: SIP/2.0/UDP pcscf1.home1.net;branch=z9hG4bK431h23.1, SIP/2.0/UDP


183 Session Progress (S-CSCF to P-CSCF)

SIP/2.0 183 Session Progress


62

Via: SIP/2.0/UDP pcscf1.home1.net;branch=z9hG4bK431h23.1, SIP/2.0/UDP [5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7

Record-Route: P-Asserted-Identity: P-Charging-Vector: icid-value="AyretyU0dm+6O2IrT5tAFrbHLso=023551024" Privacy: From: To: Call-ID: CSeq: Require: Contact: Allow: RSeq: Content-Type: Content-Length: v= o= s= c= t= m= b= a= a= a= a= a= a= a= a= m= b= a= a= a= a= a= a= a= a= a=


PRACK sip:[5555::eee:fff:aaa:bbb]:8805;comp=sigcomp SIP/2.0 Via: SIP/2.0/UDP pcscf1.home1.net;branch=z9hG4bK431h23.1, SIP/2.0/UDP

[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 Max-Forwards: 69 P-Access-Network-Info: Route: <sip:scscf1.home1.net;lr>, <sip:scscf2.home2.net;lr>, <sip:pcscf2.home2.net;lr> From: To: Call-ID: Cseq: Require: precondition RAck: Content-Type: Content-Length: v= o= s= c= t= m= b=


63

a= a= a= a= a= a= m= b= a= a= a= a= a= a= a= a=


SIP/2.0 200 OK Via: SIP/2.0/UDP pcscf1.home1.net;branch=z9hG4bK431h23.1, SIP/2.0/UDP

[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 From: To: Call-ID: CSeq: Content-Type: Content-Length: v= o= s= c= t= m= b= a= a= a= a= a= a= a= m= b= a= a= a= a= a= a= a= a= a=

UPDATE (P-CSCF to S-CSCF)

UPDATE sip:[5555::eee:fff:aaa:bbb]:8805;comp=sigcomp SIP/2.0 Via: SIP/2.0/UDP pcscf1.home1.net;branch=z9hG4bK431h23.1, SIP/2.0/UDP

[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 Max-Forwards: 69 P-Access-Network-Info: P-Charging-Vector: icid-value="AyretyU0dm+6O2IrT5tAFrbHLso=023551024";

ggsn=[5555::4b4:3c3:2d2:1e1]; auth-token=2A96B3AF30D1; pdp-info="pdp-item=1; pdp-sig=no; gcid=A93D238CAF; flow-id=({1,1},{1,2}), pdp-item=2; pdp-sig=no; gcid=F312D5E3BC; flow-id=({2,1},{2,2})"

Route: <sip:scscf1.home1.net;lr>, <sip:scscf2.home2.net;lr>, <sip:pcscf2.home2.net;lr>


64

From: To: Call-ID: Cseq: Content-Type: Content-Length: v= o= s= c= t= m= b= a= a= a= a= a= a= m= b= a= a= a= a= a= a= a= a=



[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 From: To: Call-ID: CSeq: Content-Type: Content-Length: v= o= s= c= t= m= b= a= a= a= a= a= a= m= b= a= a= a= a= a= a= a= a=


65

180 Ringing (S-CSCF to P-CSCF)

SIP/2.0 180 Ringing Via: SIP/2.0/UDP pcscf1.home1.net;branch=z9hG4bK431h23.1, SIP/2.0/UDP



PRACK sip:[5555::eee:fff:aaa:bbb]:8805;comp=sigcomp SIP/2.0 Via: SIP/2.0/UDP pcscf1.home1.net;branch=z9hG4bK431h23.1, SIP/2.0/UDP

[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 Max-Forwards: 69 P-Access-Network-Info: 3GPP-UTRAN-TDD; utran-cell-id-3gpp=234151D0FCE11 Route: <sip:scscf1.home1.net;lr>, <sip:scscf2.home2.net;lr>, <sip:pcscf2.home2.net;lr> From: To: Call-ID: Cseq: RAck: Content-Length:






[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 Record-Route: From: To: Call-ID: CSeq: Contact: Allow: Content-Length:


ACK sip:[5555::eee:fff:aaa:bbb]:8805;comp=sigcomp SIP/2.0 Via: SIP/2.0/UDP pcscf1.home1.net;branch=z9hG4bK431h23.1, SIP/2.0/UDP

[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 Max-Forwards: 69 Route: <sip:scscf1.home1.net;lr>,<sip:scscf2.home2.net;lr>, <sip:pcscf2.home2.net;lr> From: To:


66

Call-ID: Cseq: Content-Length:

6.5.2.1.5 被叫侧失败（位于归属网络，IMS 始发呼叫）

1. INVITE

27. 180 (Ringing)

3. INVITE

UE#1 P-CSCF S-CSCF



12. PRACK

16. 200 (OK)

25. 180 (Ringing)

28. PRACK

31. 200 (OK)

36. xxx (Error)

39. xxx (Error)

19. UPDATE

23. 200 (OK)

40. ACK

6. INVITE

26. 180 (Ringing)

9.183 (Session Progress)

34. xxx (Error)

13. Resource Reservation

5. Evaluation of Initial Filter Criterias


2. 100 (Trying)

4. 100 (Trying)

7. 100 (Trying)

14. PRACK15. PRACK

17. 200 (OK)18. 200 (OK)


24. 200 (OK)25. 200 (OK)

29. PRACK30. PRACK

32. 200 (OK)33. 200 (OK)

37. ACK

35. ACK

Home Network


图30 被叫侧失败流程（位于归属网络，IMS 始发呼叫）

xxx Error (S-CSCF to P-CSCF)

xxx Error 消息可能是"486 (Busy Here)", "403 (Forbidden)", "480 (Temporarily Unavailable)"

等消息。下图为 486（Busy here）示例：

SIP/2.0 486 Busy Here Via: SIP/2.0/UDP pcscf1.home1.net;branch=z9hG4bK431h23.1, SIP/2.0/UDP

[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 From: To: Call-ID: CSeq: Retry-After: 3600 Content-Length: 0


67


ACK tel:+1-212-555-2222 SIP/2.0 Via: SIP/2.0/UDP pcscf1.home1.net;branch=z9hG4bK431h23.1 Max-Forwards: 70 Route: <sip:scscf1.home1.net;lr> From: To: Call-ID: CSeq: 127 ACK Content-Length: 0

6.5.2.1.6 会话放弃或者资源失败（位于归属网络，IMS 始发呼叫）

1. INVITE

27. 180 (Ringing)

3. INVITE

UE P-CSCF S-CSCF


11. 183(SessionProgress)

12. PRACK

18. 200 (OK)

26. 180 (Ringing)

28. PRACK

33. 200 (OK)

19. UPDATE

22. 200 (OK)


6. INVITE8. 183 (Session

Progress)

Home Network

25. 180 (Ringing)



2. 100 (Trying)

4. 100 (Trying)

7. 100 (Trying)

14. PRACK15. PRACK


24. 200 (OK)23. 200 (OK)

17. 200 (OK)16. 200 (OK)

29. PRACK30. PRACK

32. 200 (OK)31. 200 (OK)

38. 200 (OK)

35. 200 (OK)34. CANCEL

40. 200 (OK)

37. CANCEL

39. CANCEL

36. Revoke QoSResources




42. ACK

44. ACK

46. ACK

图31 会话放弃或者资源失败（位于归属网络，IMS 始发呼叫）

CANCEL (P-CSCF to S-CSCF)

CANCEL tel:+1-212-555-2222 SIP/2.0 Via: SIP/2.0/UDP pcscf1.home1.net;branch=z9hG4bK431h23.1


68

Max-Forwards: 70 Route: <sip:scfcf1.home1.net;l From: To: Call-ID: Cseq: Content-Length:


SIP/2.0 200 OK Via: SIP/2.0/UDP pcscf1.home1.net;branch=z9hG4bK431h23.1 From: To: Call-ID: CSeq: Content-Length: 0

487 请求终止(S-CSCF to P-CSCF)

SIP/2.0 487 Request Terminated Via: SIP/2.0/UDP pcscf1.home1.net;branch=z9hG4bK431h23.1, SIP/2.0/UDP

[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 From: To: Contact: Call-ID: CSeq: Content-Length: 0


ACK tel:+1-212-555-2222 SIP/2.0 Via: SIP/2.0/UDP pcscf1.home1.net;branch=z9hG4bK431h23.1 Max-Forwards: 70 Route: <sip:scscf1.home1.net;lr> From: To: Call-ID: CSeq: 127 ACK Content-Length: 0

6.5.2.1.7 电路交换网用户向 IMS 用户发起的会话


69

MGW MGCF

Home Network

2. H.248 interactionto create connection

4. 100 Trying


8. 200 OK

9. H.248 interactionto modify connectionto reserve resources


12. UPDATE

14. 180 Ringing

15. PRACK

17.ACM

1. IAM

3. INVITE

7. PRACK

11.COT

19.ANM

20. H.248 interaction tomodify connection to

start media flow

21. ACK

CS Networks

6. Bearer related negotiation(if any)

13. 200 OK

16. 200 OK

18. 200 OK

图32 电路交换网用户向 IMS 用户发起的会话

INVITE (CS-O to S-S)

INVITE tel:+1-212-555-2222 SIP/2.0 Via: SIP/2.0/UDP mgcf1.home1.net;branch=z9hG4bK779s24.0 Max-Forwards: 70 Route: <sip:icscf1_s.home1.net;lr> P-Asserted-Identity: <tel:+1-212-555-1111> P-Charging-Vector: icid-value="AyretyU0dm+6O2IrT5tAFrbHLso=023551024"; orig-ioi=home1.net Privacy: none From: <tel:+1-212-555-1111>;tag=171828 To: <tel:+1-212-555-2222> Call-ID: cb03a0s09a2sdfglkj490333 Cseq: 127 INVITE Require: precondition Supported: 100rel Contact: <sip:mgcf1.home1.net> Allow: INVITE, ACK, CANCEL, BYE, PRACK, UPDATE Content-Type: application/sdp Content-Length: (…) v=0 o=- 2987933615 2987933615 IN IP6 5555::aaa:bbb:ccc:ddd s=- c=IN IP6 5555::aaa:bbb:ccc:ddd t=0 0 m=audio 3456 RTP/AVP 97 96 b=AS:25.4 a=curr:qos local none a=curr:qos remote none


70

a=des:qos mandatory local sendrecv a=des:qos none remote sendrecv a=rtpmap:97 AMR a=fmtp:97 mode-set=0,2,5,7; mode-change-period=2 a=rtpmap:96 telephone-event a=maxptime:20

Request-URI:用户的 E.164 号码

Via:主叫 MGCF 的 IP 地址或者 FQDN。

P-Asserted-Identity:订阅用户的 TEL URL。

P-Charging-Vector:MGCF 插入此头域作为 ICID 参数，ICID 参数是唯一的。

Cseq:随机开始的数。

Contact:包含 MGCF 的 IP 地址或者 FQDN 的 SIP URI。

SDP:包含 MGW 支持的编码集。

100 Trying (S-S to CS-O)

SIP/2.0 100 Trying Via: SIP/2.0/UDP mgcf1.home1.net;branch=z9hG4bK779s24.0 From: To: Call-ID: CSeq: Content-Length: 0

183 Session Progress (S-S to CS-O)

SIP/2.0 183 Session Progress Via: SIP/2.0/UDP mgcf1.home1.net;branch=z9hG4bK779s24.0 Record-Route: <sip:pcscf2.home1.net;lr>, <sip:scscf2.home1.net;lr> P-Asserted-Identity: "John Smith" <tel:+1-212-555-2222> P-Charging-Vector: icid-value="AyretyU0dm+6O2IrT5tAFrbHLso=023551024"; orig-ioi=home1.net;

term-ioi=visit1.net P-Charging-Function-Addresses: ccf=[5555::b99:c88:d77:e66]; ccf=[5555::a55:b44:c33:d22];

ecf=[5555::1ff:2ee:3dd:4cc]; ecf=[5555::6aa:7bb:8cc:9dd] Privacy: none From: To: <tel:+1-212-555-2222>;tag=314159 Call-ID: CSeq: Require: 100rel Contact: <sip:[5555::eee:fff:aaa:bbb]:8805;comp=sigcomp> Allow: INVITE, ACK, CANCEL, BYE, PRACK, UPDATE, REFER, MESSAGE RSeq: 9021 Content-Type: application/sdp Content-Length: (…) v=0 o=- 2987933623 2987933623 IN IP6 5555::eee:fff:aaa:bbb s=- c=IN IP6 5555::eee:fff:aaa:bbb t=0 0 m=audio 6544 RTP/AVP 97 96 b=AS:25.4 a=curr:qos local none a=curr:qos remote none a=des:qos mandatory local sendrecv a=des:qos mandatory remote sendrecv a=conf:qos remote sendrecv a=rtpmap:97 AMR a=fmtp:97 mode-set=0,2,5,7; mode-change-period=2 a=rtpmap:96 telephone-event a=maxptime:20


71

P-Charging-Function-Addresses:S-CSCF 传给 MGCF 此头域用于计费。

PRACK (CS-O to S-S)

PRACK sip:[5555::eee:fff:aaa:bbb]:8805;comp=sigcomp SIP/2.0 Via: SIP/2.0/UDP mgcf1.home1.net;branch=z9hG4bK779s24.0 Max-Forwards: 70 Route: <sip:scscf2.home1.net;lr>, <sip:pcscf2.home1.net;lr> From: <tel:+1-212-555-1111>;tag=171828 To: <tel:+1-212-555-2222>;tag=314159 Call-ID: cb03a0s09a2sdfglkj490333 Cseq: 128 PRACK Require: preconditions RAck: 9021 127 INVITE Content-Length: 0

Via:MGCF 的 IP 地址或者 FQDN。

From:/To:/Call-ID:复制 183 Session Progress 消息中的相应字段值，包含 tag 参数。

Cseq:取比前一个请求中 Cseq 大的值。

200 OK (S-S to CS-O)


UPDATE (CS-O to S-S)

UPDATE sip:[5555::eee:fff:aaa:bbb]:8805;comp=sigcomp SIP/2.0 Via: SIP/2.0/UDP mgcf1.home1.net;branch=z9hG4bK779s24.0 Max-Forwards: 70 Route: <sip:scscf2.home1.net;lr>, <sip:pcscf2.home1.net;lr> From: <tel:+1-212-555-1111>;tag=171828 To: <tel:+1-212-555-2222>;tag=314159 Call-ID: cb03a0s09a2sdfglkj490333 Cseq: 129 UPDATE Content-Type: application/sdp Content-Length: (…) v=0 o=- 2987933615 2987933616 IN IP6 5555::aaa:bbb:ccc:ddd s=- c=IN IP6 5555::aaa:bbb:ccc:ddd t=0 0 m=audio 3456 RTP/AVP 97 96 b=AS:25.4 a=curr:qos local sendrecv a=curr:qos remote none a=des:qos mandatory local sendrecv a=des:qos mandatory remote sendrecv a=rtpmap:97 AMR a=fmtp:97 mode-set=0,2,5,7; mode-change-period=2 a=rtpmap:96 telephone-event a=maxptime:20

Via:主叫 MGCF 的 IP 地址或 FQDN。

Route:取保存的 Route 头域值，不包括第一个值。

From:/To:/Call-ID:复制 183 Session Progress 消息中的相应字段值，包含 tag 参数。

Cseq:取比前一个请求中 Cseq 大的值。


72


SIP/2.0 200 OK Via: SIP/2.0/UDP mgcf1.home1.net;branch=z9hG4bK779s24.0 From: To: Call-ID: CSeq: Content-Type: application/sdp Content-Length: (…) v=0 o=- 2987933623 2987933624 IN IP6 5555::aaa:bbb:ccc:ddd s=- c=IN IP6 5555::aaa:bbb:ccc:ddd t=0 0 m=audio 3456 RTP/AVP 97 96 b=AS:25.4 a=curr:qos local sendrecv a=curr:qos remote sendrecv a=des:qos mandatory local sendrecv a=des:qos mandatory remote sendrecv a=rtpmap:97 AMR a=fmtp:97 mode-set=0,2,5,7; mode-change-period=2 a=rtpmap:96 telephone-event a=maxptime:20

180 Ringing (S-S to CS-O)

SIP/2.0 180 Ringing Via: SIP/2.0/UDP mgcf1.home1.net;branch=z9hG4bK779s24.0 Record-Route: <sip:pcscf2.home1.net;lr>, <sip:scscf2.home1.net;lr> Require: 100rel From: To: Call-ID: CSeq: 127 INVITE Contact: <sip:[5555::eee:fff:aaa:bbb]:8805;comp=sigcomp> Allow: INVITE, ACK, CANCEL, BYE, PRACK, UPDATE, REFER, MESSAGE RSeq: 9022 Content-Length: 0

PRACK (CS-O to S-S)

PRACK sip:[5555::eee:fff:aaa:bbb]:8805;comp=sigcomp SIP/2.0 Via: SIP/2.0/UDP mgcf1.home1.net;branch=z9hG4bK779s24.0 Max-Forwards: 70 Route: <sip:scscf2.home1.net;lr>, <sip:pcscf2.home1.net;lr> From: <tel:+1-212-555-1111>;tag=171828 To: <tel:+1-212-555-2222>;tag=314159 Call-ID: cb03a0s09a2sdfglkj490333 Cseq: 130 PRACK RAck: 9022 127 INVITE Content-Length: 0


SIP/2.0 200 OK Via: SIP/2.0/UDP mgcf1.home1.net;branch=z9hG4bK779s24.0 From: To: Call-ID: CSeq:


73

Content-Length: 0


SIP/2.0 200 OK Via: SIP/2.0/UDP mgcf1.home1.net;branch=z9hG4bK779s24.0 Record-Route: <sip:pcscf2.home1.net;lr>, <sip:scscf2.home1.net;lr> From: To: Call-ID: CSeq: 127 INVITE Contact: <sip:[5555::eee:fff:aaa:bbb]:8805;comp=sigcomp> Allow: INVITE, ACK, CANCEL, BYE, PRACK, UPDATE, REFER, MESSAGE Content-Length: 0

ACK (CS-O to S-S)

ACK sip:[5555::eee:fff:aaa:bbb]:8805;comp=sigcomp SIP/2.0 Via: SIP/2.0/UDP mgcf1.home1.net;branch=z9hG4bK779s24.0 Max-Forwards: 70 Route: <sip:scscf2.home1.net;lr>, <sip:pcscf2.home1.net;lr> From: To: Call-ID: Cseq: 127 ACK Content-Length: 0

Cseq:与主叫流程的 INVITE 消息[流程图中第三步]中的 Cseq 值相同。

6.5.2.1.8 被叫侧失败（电路交换网用户始发呼叫）

1. IAM

16. IP-ACM

2. IP-IAM

PSTN T-SGW MGW

7. PRACK8. 200 OK

13. 180 Ringing14. PRACK15. 200 OK

20. IP-REL21. REL

11. UPDATE12. 200 OK

19. ACK

MGCF

4. INVITE

6. 183 SDP

18. xxx Error

17. ACM

Home Network


3. H.248 interaction tocreate connection

5. 100 Trying

9. H.248 interaction tomodify connection

to reserve resources

22. H.248 interaction todelete connection


74

图33 被叫侧失败流程（电路交换网用户始发呼叫）

xxx Error (S-S to CS-O)

被叫流程检测到错误，返回 4XX 响应。

错误响应可能是"486 Busy", "403 Service Denied", "480 Temporarily Unavailable"或者其他

消息，"486 Busy"消息示例如下：

SIP/2.0 486 Busy Here Via: SIP/2.0/UDP mgcf1.home1.net;branch=z9hG4bK779s24.0 From: <tel:+1-212-555-1111>;tag=171828 To: <tel:+1-212-555-2222>;tag=314159 Call-ID: cb03a0s09a2sdfglkj490333 Cseq: 127 INVITE Retry-After: 3600 Content-Length: 0

ACK (CS-O to S-S)

ACK tel:+1-212-555-2222 SIP/2.0 Via: SIP/2.0/UDP mgcf1.home1.net;branch=z9hG4bK779s24.0 Max-Forwards: 70 Route: <sip:icscf1_s.home1.net;lr> From: To: Call-ID: CSeq: 127 ACK Content-Length: 0

6.5.2.1.9 会话放弃或者资源失败（电路交换网用户始发呼叫）


75

1. IAM

16. IP-ACM

2. IP-IAM

PSTN T-SGW MGW

7. PRACK8. 200 OK

13. 180 Ringing14. PRACK15. 200 OK

11. UPDATE12. 200 OK

20. CANCEL

MGCF

4. INVITE

6. 183 SDP

21. 200 OK

17. ACM

Home Network


3. H.248 interaction tocreate connection

5. 100 Trying

9. H.248 interaction tomodify connection

to reserve resources

22. H.248 interaction todelete connection

18. REL19. IP-REL

23. 487Cancelled

24. ACK

图34 会话放弃或者资源失败（电路交换网用户始发呼叫）

CANCEL (CS-O to S-S)

CANCEL tel:+1-212-555-2222 SIP/2.0 Via: SIP/2.0/UDP mgcf1.home1.net;branch=z9hG4bK779s24.0 Max-Forwards: 70 Route: <sip:icscf1_s.home1.net;lr> From: <tel:+1-212-555-1111>;tag=171828 To: <tel:+1-212-555-2222> Call-ID: cb03a0s09a2sdfglkj490333 Cseq: 127 CANCEL Content-Length: 0



487 请求终止 (S-S to CS-O)

SIP/2.0 487 Request Terminated


76

Via: SIP/2.0/UDP mgcf1.home1.net;branch=z9hG4bK779s24.0 From: To: Call-ID: Cseq: 127 INVITE Retry-After: 3600 Content-Length: 0

ACK (CS-O to S-S)

ACK tel:+1-212-555-2222 SIP/2.0 Via: SIP/2.0/UDP mgcf1.home1.net;branch=z9hG4bK779s24.0 Route: <sip:icscf1_s.home1.net;lr> Max-Forwards: 70 From: To: Call-ID: CSeq: 127 ACK Content-Length: 0

6.5.2.2 S-S 流程 6.5.2.2.1 主被叫分属不同网络运营商

4. INVITE

29. 180 Ringing

S-CSCF#1 S-CSCF#2


16. PRACK

19. 200 OK

32 PRACK

35. 200 OK

39. 200 OK

22. UPDATE

25. 200 OK

42. ACK

I-CSCF HSS

7 INVITE


1. INVITE


10. INVITE


28. 180 Ringing

31. 180 Ringing

38. 200 OK

41. 200 OK

Home Network#2Originating Network Terminating Network

30. 180 Ringing

40. 200 OK

2. 100 Trying

8. 100 Trying

11. 100 Trying

17. PRACK 18. PRACK

5. 100 Trying

20. 200 OK21. 200 OK


26. 200 OK27. 200 OK

33. PRACK 34. PRACK

36. 200 OK37. 200 OK

43. ACK44. ACK

3. Evaluation ofinitial filte criterias

9. Evaluation ofnitial filtr criterias

Home Network#1



77

图35 主被叫分属不同网络运营商

INVITE (S-CSCF to I-CSCF)

INVITE sip:[email protected] SIP/2.0 Via: SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1, SIP/2.0/UDP


Max-Forwards: 68 Record-Route: <sip:scscf1.home1.net;lr>, <sip:pcscf1.visited1.net;lr> P-Asserted-Identity: "John Doe" <sip:[email protected]>, <tel:+1-212-555-1111> P-Charging-Vector: icid-value="AyretyU0dm+6O2IrT5tAFrbHLso=023551024"; orig-ioi=home1.net Privacy: From: To: Call-ID: Cseq: Require: Supported: Contact: Allow: Content-Type: Content-Length: (…) v= o= s= c= t= m= b= a= a= a= a= a= a= a= m= b= a= a= a= a= a= a= a= a=

Request-URI:当发往 S-CSCF 的 INVITE 请求中的 Reques-URI 包含 TEL-URL 时，必须将 TEL-URL 转

换成可路由的 SIP-URL 格式，S-CSCF 使用 ENUM-DNS 协议（参考 RFC 2916）或者合适的转换数据库来完

成转换，ENUM 数据库的内容不在此规范中。

P-Asserted-Identity: S-CSCF 在 P-Asserted-Identity 插入相应的 TEL URL，当 INVITE 消息发向

MGCF 时，目地网络可以知道这个地址。

P-Charging-Vector:S-CSCF 所在网络的标识以及 IOI 参数。

100 Trying (I-CSCF to S-CSCF)





78

Content-Length: 0

INVITE (I-CSCF to S-CSCF)

INVITE sip:[email protected] SIP/2.0 Via: SIP/2.0/UDP icscf2_s.home2.net;branch=z9hG4bK871y12.1, SIP/2.0/UDP

scscf1.home1.net;branch=z9hG4bK332b23.1, SIP/2.0/UDP pcscf1.visited1.net;branch=z9hG4bK240f34.1, SIP/2.0/UDP [5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7

Max-Forwards: 67 Route: <sip:scscf2.home2.net;lr> Record-Route: <sip:scscf1.home1.net;lr>, <sip:pcscf1.visited1.net;lr> P-Asserted-Identity: P-Charging-Vector: Privacy: From: To: Call-ID: Cseq: Require: Supported: Contact: Allow: Content-Type: Content-Length: v= o= s= c= t= m= b= a= a= a= a= a= a= a= m= b= a= a= a= a= a= a= a= a=

100 Trying (S-CSCF to I-CSCF)

SIP/2.0 100 Trying Via: SIP/2.0/UDP icscf2_s.home2.net;branch=z9hG4bK871y12.1, SIP/2.0/UDP



183 Session Progress (S-CSCF to I-CSCF)


79

SIP/2.0 183 Session Progress Via: SIP/2.0/UDP icscf2_s.home2.net;branch=z9hG4bK871y12.1, SIP/2.0/UDP


Record-Route: P-Asserted-Identity: "John Smith" <sip:[email protected]>, <tel:+1-212-555-2222> P-Charging-Vector: icid-value="AyretyU0dm+6O2IrT5tAFrbHLso=023551024"; orig-ioi=home1.net;

term-ioi=home2.net P-Charging-Function-Addresses: ccf=[5555::b99:c88:d77:e66]; ccf=[5555::a55:b44:c33:d22];

ecf=[5555::1ff:2ee:3dd:4cc]; ecf=[5555::6aa:7bb:8cc:9dd] Privacy: From: To: Call-ID: CSeq: Require: Contact: Allow: RSeq: Content-Type: Content-Length: v= o= s= c= t= m= b= a= a= a= a= a= a= a= a= m= b= a= a= a= a= a= a= a= a= a=

P-Asserted-Identity:S-CSCF 在 P-Asserted-Identity 插入相应的 TEL URL，当 INVITE 消息发向

MGCF 时，目地网络可以知道这个地址。

P-Charging-Vector:S-CSCF 所在网络的标识以及 IOI 参数。

P-Charging-Function-Addresses:S-CSCF 传送此头域给 I-CSCF 用于计费。

183 Session Progress (I-CSCF to S-CSCF)



Record-Route: P-Asserted-Identity: P-Charging-Vector: Privacy: From: To:


80

Call-ID: CSeq: Require: Contact: Allow: RSeq: Content-Type: Content-Length: v= o= s= c= t= m= b= a= a= a= a= a= a= a= a= m= b= a= a= a= a= a= a= a= a= a=

PRACK (S-CSCF to S-CSCF)

PRACK sip:[5555::eee:fff:aaa:bbb]:8805;comp=sigcomp SIP/2.0 Via: SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1, SIP/2.0/UDP


Max-Forwards: 68 Route: <sip:scscf2.home2.net;lr>, <sip:pcscf2.visited2.net;lr> From: To: Call-ID: Cseq: Require: RAck: Content-Type: Content-Length: v= o= s= c= t= m= b= a= a= a= a= a= a= m= b=


81

a= a= a= a= a= a= a= a=

200 OK (S-CSCF to S-CSCF)



From: To: Call-ID: CSeq: Content-Type: Content-Length: v= o= s= c= t= m= b= a= a= a= a= a= a= a= m= b= a= a= a= a= a= a= a= a= a=

UPDATE (S-CSCF to S-CSCF)

UPDATE sip:[5555::eee:fff:aaa:bbb]:8805;comp=sigcomp SIP/2.0 Via: SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1, SIP/2.0/UDP


Max-Forwards: 68 Route: <sip:scscf2.home2.net;lr>, <sip:pcscf2.visited2.net;lr> P-Charging-Vector: icid-value="AyretyU0dm+6O2IrT5tAFrbHLso=023551024"; orig-ioi=home1.net;

term-ioi=home2.net From: To: Call-ID: Cseq: Content-Type: Content-Length: v= o=


82

s= c= t= m= b= a= a= a= a= a= a= m= b= a= a= a= a= a= a= a= a=




From: To: Call-ID: CSeq: Content-Type: Content-Length: v= o= s= c= t= m= b= a= a= a= a= a= a= m= b= a= a= a= a= a= a= a= a=

180 Ringing (S-CSCF to I-CSCF)

SIP/2.0 180 Ringing Via: SIP/2.0/UDP icscf2_s.home2.net;branch=z9hG4bK871y12.1, SIP/2.0/UDP


Record-Route:


83

P-Charging-Vector: icid-value="AyretyU0dm+6O2IrT5tAFrbHLso=023551024"; orig-ioi=home1.net; term-ioi=home2.net

From: To: Call-ID: CSeq: Require: Contact: Allow: RSeq: Content-Length:

180 Ringing (I-CSCF to S-CSCF)

SIP/2.0 180 Ringing Via: SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1, SIP/2.0/UDP


Record-Route: P-Charging-Vector: From: To: Call-ID: CSeq: Require: Contact: Allow: RSeq: Content-Length:




Max-Forwards: 68 Route: <sip:scscf2.home2.net;lr>, <sip:pcscf2.visited2.net;lr> From: To: Call-ID: Cseq: RAck: Content-Length:




From: To: Call-ID: CSeq: Content-Length:

200 OK (S-CSCF to I-CSCF)



Record-Route:


84

P-Charging-Vector: icid-value="AyretyU0dm+6O2IrT5tAFrbHLso=023551024"; orig-ioi=home1.net; term-ioi=home2.net


200 OK (I-CSCF to S-CSCF)



Record-Route: P-Charging-Vector: From: To: Call-ID: CSeq: Contact: Allow: Content-Length:

ACK (S-CSCF to S-CSCF)

ACK sip:[5555::eee:fff:aaa:bbb]:8805;comp=sigcomp SIP/2.0 Via: SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1, SIP/2.0/UDP


Max-Forwards: 68 Route: <sip:scscf2.home2.net;lr>, <sip:pcscf2.visited2.net;lr> From: To: Call-ID: Cseq: Content-Length:

6.5.2.2.2 被叫侧失败（主被叫处在不同运营商）


85

4. INVITE

29. 180 Ringing

S-CSCF#1 S-CSCF#2

13. 183 SDP

16. PRACK

19. 200 OK

32. PRACK

35. 200 OK

40. xxx Error

22. UPDATE

25. 200 OK

45. ACK

I-CSCF HSS

7. INVITE

14. 183 SDP

1. INVITE

15. 183 SDP

10. INVITE

12. 183 SDP

28. 180 Ringing

31. 180 Ringing

38. xxx Error

44. xxx Error


30. 180 Ringing

42. xxx Error

2. 100 Trying

8. 100 Trying

11. 100 Trying

17. PRACK18. PRACK

5. 100 Trying

20. 200 OK21. 200 OK

23.UPDATE 24. UPDATE

26. 200 OK27. 200 OK

33. PRACK34. PRACK

36. 200 OK37. 200 OK

43. ACK

39. ACK



Home Network#1

41. ACK

6. Cx: User locationquery

图36 被叫侧失败流程（主被叫处在不同运营商）

xxx Error (S-CSCF to I-CSCF)



SIP/2.0 486 Busy Here Via: SIP/2.0/UDP icscf2_s.home2.net;branch=z9hG4bK871y12.1, SIP/2.0/UDP


From: To: Call-ID: CSeq: Retry-After: 3600 Content-Length: 0

ACK (I-CSCF to S-CSCF)


86

ACK sip:[email protected] SIP/2.0 Via: SIP/2.0/UDP icscf2_s.home1.net;branch=z9hG4bK332b23.1 Max-Forwards: 70 Route: <sip:scscf2.home2.net;lr> From: To: Call-ID: CSeq: 127 ACK Content-Length: 0

xxx Error (I-CSCF to S-CSCF)



SIP/2.0 486 Busy Here Via: SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1, SIP/2.0/UDP



ACK (S-CSCF to I-CSCF)

ACK sip:[email protected] SIP/2.0 Via: SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1 Max-Forwards: 70 From: To: Call-ID: CSeq: 127 ACK Content-Length: 0

6.5.2.2.3 主叫侧失败（主被叫处在不同运营商）


87

4. INVITE

29. 180 Ringing

S-CSCF#1 S-CSCF#2

13. 183

16. PRACK

19. 200 OK

32. PRACK

35. 200 OK

43. 200 OK

22. UPDATE

25. 200 OK

38. CANCEL

I-CSCF HSS

7. INVITE

14. 183

1. INVITE

15. 183

10. INVITE

12. 183

28. 180 Ringing

31. 180 Ringing

45. 200 OK

39. 200 OK


30. 180 Ringing

41. 200 OK

2. 100 Trying

8. 100 Trying

11. 100 Trying

17. PRACK18. PRACK

5. 100 Trying

20. 200 OK21. 200 OK

23.UPDATE 24. UPDATE

26. 200 OK27. 200 OK

33. PRACK34. PRACK

36. 200 OK37. 200 OK

40. CANCEL

44. CANCEL

3. Evaluation of initialfilter criterias


Home Network#1

42. CANCEL

46. 487 Cancelled47. ACK





图37 主叫侧失败流程（主被叫处在不同运营商）

CANCEL (S-CSCF to I-CSCF)

CANCEL sip:[email protected] SIP/2.0 Via: SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1 Max-Forwards: 70 From: To: Call-ID: Cseq: Content-Length:


SIP/2.0 200 OK Via: SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1


88

From: To: Call-ID: CSeq: 127 CANCEL Content-Length: 0

CANCEL (I-CSCF to S-CSCF)

CANCEL sip:[email protected] SIP/2.0 Via: SIP/2.0/UDP icscf2_s.home2.net;branch=z9hG4bK871y12.1 Max-Forwards: 70 Route: <sip:scscf2.home2.net;lr> From: To: Call-ID: Cseq: Content-Length:


SIP/2.0 200 OK Via: SIP/2.0/UDP icscf2_s.home2.net;branch=z9hG4bK871y12.1 From: To: Call-ID: CSeq: 127 CANCEL Content-Length: 0

487 Request Terminated (S-CSCF to I-CSCF)

SIP/2.0 487 Request Terminated Via: SIP/2.0/UDP icscf2_s.home2.net;branch=z9hG4bK871y12.1, SIP/2.0/UDP




ACK sip:[email protected] SIP/2.0 Via: SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1 Max-Forwards: 70 Route: <sip:scscf2.home2.net;lr> From: To: Call-ID: CSeq: 127 ACK Content-Length: 0

487 Request Terminated (I-CSCF to S-CSCF)

SIP/2.0 487 Request Terminated Via: SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1, SIP/2.0/UDP




89

Retry-After: 3600 Content-Length: 0



6.5.2.2.4 主被叫属于同一运营商

4. INVITE

29. 180 Ringing

S-CSCF#1 S-CSCF#2


16. PRACK

19. 200 OK

32. PRACK

35. 200 OK

39. 200 OK

22. UPDATE

25. 200 OK

42. ACK

I-CSCF HSS

7. INVITE


1. INVITE


10. INVITE


28. 180 Ringing

31. 180 Ringing

38. 200 OK

41. 200 OK

Home NetworkOriginating Network Terminating Network

30. 180 Ringing

40. 200 OK

2. 100Trying

8. 100 Trying

11. 100 Trying

17. PRACK 18. PRACK

5. 100Trying

20. 200 OK21. 200 OK


26. 200 OK27. 200 OK

33. PRACK 34. PRACK

36. 200 OK37. 200 OK

43. ACK44. ACK

3. Evaluation ofFilter Criteria

9. Evaluation ofFilter Criterial


图38 主被叫属于同一运营商





90

Max-Forwards: 68 Route: <sip:icscf2_s.home1.net;lr> Record-Route: <sip:scscf1.home1.net;lr>, <sip:pcscf1.home1.net;lr> P-Asserted-Identity: P-Charging-Vector: icid-value="AyretyU0dm+6O2IrT5tAFrbHLso=023551024"; orig-ioi=home1.net Privacy: From: To: Call-ID: Cseq: Require: Supported: Contact: Allow: Content-Type: Content-Length: (…) v= o= s= c= t= m= b= a= a= a= a= a= a= a= m= b= a= a= a= a= a= a= a= a=

Request-URI:当发往 S-CSCF 的 INVITE 请求中的 Reques-URI 包含 TEL-URL 时，必须将 TEL-URL 转

换成可路由的 SIP-URL 格式，S-CSCF 使用 ENUM-DNS 协议（参考 RFC 2916）或者合适的转换数据库来完

成转换，ENUM 数据库的内容不在此规范中。

P-Charging-Vector:S-CSCF 所在网络的标识以及主叫 IOI 参数。









91

Max-Forwards: 67 Route: <sip:scscf2.home1.net;lr> Record-Route: <sip:scscf1.home1.net;lr>, <sip:pcscf1.home1.net;lr> Supported: P-Asserted-Identity: P-Charging-Vector: Privacy: From: To: Call-ID: Cseq: Require: Supported: Contact: Allow: Content-Type: Content-Length: v= o= s= c= t= m= b= a= a= a= a= a= a= a= m= b= a= a= a= a= a= a= a= a=





183 Session Progress (S-CSCF to I-CSCF)

SIP/2.0 183 Session Progress Via: SIP/2.0/UDP icscf2_s.home1.net;branch=z9hG4bK871y12.1, SIP/2.0/UDP


Record-Route: P-Asserted-Identity: P-Charging-Vector: icid-value="AyretyU0dm+6O2IrT5tAFrbHLso=023551024"; orig-ioi=home1.net;

term-ioi=home1.net


92

P-Charging-Function-Addresses: ccf=[5555::b99:c88:d77:e66]; ccf=[5555::a55:b44:c33:d22]; ecf=[5555::1ff:2ee:3dd:4cc]; ecf=[5555::6aa:7bb:8cc:9dd]

Privacy: From: To: Call-ID: CSeq: Require: Contact: Allow: RSeq: Content-Type: Content-Length: v= o= s= c= t= m= b= a= a= a= a= a= a= a= a= m= b= a= a= a= a= a= a= a= a= a=

P-Charging-Vector:S-CSCF 所在网络的标识以及被叫 IOI 参数。

P-Charging-Function-Addresses:S-CSCF 传给 I-CSCF 此头域用于计费。

183 Session Progress (I-CSCF to S-CSCF)



Record-Route: P-Asserted-Identity: P-Charging-Vector: Privacy: From: To: Call-ID: CSeq: Require: Contact: Allow: RSeq: Content-Type: Content-Length: v= o= s= c=


93

t= m= b= a= a= a= a= a= a= a= a= m= b= a= a= a= a= a= a= a= a= a=




Max-Forwards: 68 Route: <sip:scscf2.home1.net;lr>, <sip:pcscf2.home1.net;lr> From: To: Call-ID: Cseq: Require: RAck: Content-Type: Content-Length: v= o= s= c= t= m= b= a= a= a= a= a= a= m= b= a= a= a= a= a= a= a= a=


SIP/2.0 200 OK


94

Via: SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1, SIP/2.0/UDP pcscf1.home1.net;branch=z9hG4bK431h23.1, SIP/2.0/UDP [5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7

From: To: Call-ID: CSeq: Content-Type: Content-Length: v= o= s= c= t= m= b= a= a= a= a= a= a= a= m= b= a= a= a= a= a= a= a= a= a=

UPDATE (S-CSCF to S-CSCF)

UPDATE sip:[5555::eee:fff:aaa:bbb]:8805;comp=sigcomp SIP/2.0 Via: SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1, SIP/2.0/UDP


Max-Forwards: 68 Route: <sip:scscf2.home1.net;lr>, <sip:pcscf2.home1.net;lr> From: To: Call-ID: Cseq: Content-Type: Content-Length: v= o= s= c= t= m= b= a= a= a= a= a= a= m= b= a= a=


95

a= a= a= a= a= a=




From: To: Call-ID: CSeq: Content-Type: Content-Length: v= o= s= c= t= m= b= a= a= a= a= a= a= m= b= a= a= a= a= a= a= a= a=

180 Ringing (S-CSCF to I-CSCF)

SIP/2.0 180 Ringing Via: SIP/2.0/UDP icscf2_s.home1.net;branch=z9hG4bK871y12.1, SIP/2.0/UDP



180 Ringing (I-CSCF to S-CSCF)

SIP/2.0 180 Ringing


96

Via: SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1, SIP/2.0/UDP pcscf1.home1.net;branch=z9hG4bK431h23.1, SIP/2.0/UDP [5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7





Max-Forwards: 68 Route: <sip:scscf2.home1.net;lr>, <sip:pcscf2.home1.net;lr> From: To: Call-ID: Cseq: RAck: Content-Length:








Record-Route: From: To: Call-ID: CSeq: Contact: Allow: Content-Length:




Record-Route:


97


ACK (S-CSCF to S-CSCF)

ACK sip:[5555::eee:fff:aaa:bbb]:8805;comp=sigcomp SIP/2.0 Via: SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1, SIP/2.0/UDP


Max-Forwards: 68 Route: <sip:scsf2.home1.net;lr>, <sip:pcscf2.home1.net;lr> From: To: Call-ID: Cseq: Content-Length:

6.5.2.2.5 被叫 UE 忙、不能或者不愿意应答会话（主被叫在同一运营商）

S-CSCF#1 HSS S-CSCF#2

10. INVITE


2. 100 Trying

Home Network

11. 486 Busy Here

12. ACK

17. 486 BusyHere

I-CSCF1. INVITE

4. INVITE

7. INVITE8. 100 Trying

5. 100 Trying

13. 486 Busy Here

15. 486 Busy Here

16. ACK

14. ACK

18. ACK



图39 被叫 UE 忙、不能或者不愿意应答会话（主被叫在同一运营商）

486 Busy Here (S-CSCF to I-CSCF)



SIP/2.0 486 Busy Here Via: SIP/2.0/UDP icscf2_s.home1.net;branch=z9hG4bK871y12.1, SIP/2.0/UDP

scscf1.home1.net;branch=z9hG4bK332b23.1, SIP/2.0/UDP pcscf1.home1.net;branch=z9hG4bK431h23.1, SIP/2.0/UDP [5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7)

From: To:


98

Call-ID: CSeq: Retry-After: 3600 Content-Length: 0


ACK sip:[email protected] SIP/2.0 Via: SIP/2.0/UDP icscf2_s.home1.net;branch=z9hG4bK871y12.1 Max-Forwards: 70 Route: <sip:scscf2.home1.net;lr> From: To: Call-ID: CSeq: 127 ACK Content-Length: 0

486 Busy Here (I-CSCF to S-CSCF)

SIP/2.0 486 Busy Here Via: SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1, SIP/2.0/UDP

pcscf1.home1.net;branch=z9hG4bK431h23.1, SIP/2.0/UDP [5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7)

From: To: Call-ID: CSeq: Contact: Retry-After: 3600 Content-Length: 0



6.5.2.2.6 同一个域内电路交换网用户做被叫的流程


99

4. INVITE

19. 180 Ringing

S-CSCF MGCF


11. PRACK

22. PRACK

26. 200 OK

15. UPDATE

29. ACK

BGCF

6. INVITE


1. INVITE


21. 180 Ringing

28. 200 OK

Home NetworkOriginating Network

20. 180 Ringing

27. 200 OK

2. 100 Trying

7. 100 Trying

12. PRACK

5. 100 Trying

13. 200 OK14. 200 OK

16. UPDATE

17. 200 OK18. 200 OK

23. PRACK

24. 200 OK25. 200 OK

30. ACK


图40 同一个域内电路交换网用户做被叫的流程

INVITE (MO to S-S#3)


[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 Max-Forwards: 69 Route: <sip:scscf1.home1.net;lr> Record-Route: <sip:pcscf1.home1.net;lr> P-Asserted-Identity: "John Doe" <tel:+1-212-555-1111> P-Access-Network-Info: 3GPP-UTRAN-TDD; utran-cell-id-3gpp=234151D0FCE11 P-Charging-Vector: icid-value="AyretyU0dm+6O2IrT5tAFrbHLso=023551024" Privacy: none From: <sip:[email protected]>;tag=171828 To: <tel:+1-212-555-2222> Call-ID: cb03a0s09a2sdfglkj490333 Cseq: 127 INVITE Require: precondition Supported: 100rel Contact: <sip:[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp> Allow: INVITE, ACK, CANCEL, BYE, PRACK, UPDATE, REFER, MESSAGE Content-Type: application/sdp Content-Length: (…) v=0


100

o=- 2987933615 2987933615 IN IP6 5555::aaa:bbb:ccc:ddd s=- c=IN IP6 5555::aaa:bbb:ccc:ddd t=0 0 m=video 3400 RTP/AVP 98 99 b=AS:75 a=curr:qos local none a=curr:qos remote none a=des:qos mandatory local sendrecv a=des:qos none remote sendrecv a=rtpmap:98 H263 a=fmtp:98 profile-level-id=0 a=rtpmap:99 MP4V-ES m=audio 3456 RTP/AVP 97 96 b=AS:25.4 a=curr:qos local none a=curr:qos remote none a=des:qos mandatory local sendrecv a=des:qos none remote sendrecv a=rtpmap:97 AMR a=fmtp:97 mode-set=0,2,5,7; mode-change-period=2 a=rtpmap:96 telephone-event a=maxptime:20

100 Trying (S-S#3 to MO)



183 Session Progress (S-S#3 to MO)

SIP/2.0 183 Session Progress Via: SIP/2.0/UDP pcscf1.home1.net;branch=z9hG4bK431h23.1, SIP/2.0/UDP

[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 Record-Route: P-Asserted-Identity: P-Charging-Vector: icid-value="AyretyU0dm+6O2IrT5tAFrbHLso=023551024" Privacy: From: To: Call-ID: CSeq: Require: Contact: Allow: RSeq: Content-Type: Content-Length: v= o= s= c= t= m= m= b= a= a= a= a=


101

a= a= a= a= a=

PRACK (MO to S-S#3)

PRACK sip:mgcf1.home1.net SIP/2.0 Via: SIP/2.0/UDP pcscf1.home1.net;branch=z9hG4bK431h23.1, SIP/2.0/UDP

[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 Max-Forwards: 69 P-Access-Network-Info: 3GPP-UTRAN-TDD; utran-cell-id-3gpp=234151D0FCE11 Route: <sip:scscf1.home1.net;lr> From: <sip:[email protected]>;tag=171828 To: <tel:+1-212-555-2222>;tag=314159 Call-ID: cb03a0s09a2sdfglkj490333 Cseq: 128 PRACK Require: precondition RAck: 9021 127 INVITE Content-Length: 0

200 OK (S-S#3 to MO)



UPDATE (MO to S-S#3)

UPDATE sip:mgcf1.home1.net SIP/2.0 Via: SIP/2.0/UDP pcscf1.home1.net;branch=z9hG4bK431h23.1, SIP/2.0/UDP

[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 Max-Forwards: 69 P-Access-Network-Info: 3GPP-UTRAN-TDD; utran-cell-id-3gpp=234151D0FCE11 Route: <sip:scscf1.home1.net;lr> P-Charging-Vector: icid-value="AyretyU0dm+6O2IrT5tAFrbHLso=023551024";


From: <sip:[email protected]>;tag=171828 To: <tel:+1-212-555-2222>;tag=314159 Call-ID: cb03a0s09a2sdfglkj490333 Cseq: 129 UPDATE Content-Type: application/sdp Content-Length: (…) v=0 o=- 2987933615 2987933616 IN IP6 5555::aaa:bbb:ccc:ddd s=- c=IN IP6 5555::aaa:bbb:ccc:ddd t=0 0 m=video 0 RTP/AVP 98 99 m=audio 3456 RTP/AVP 97 96 b=AS:25.4 a=curr:qos local sendrecv a=curr:qos remote none a=des:qos mandatory local sendrecv a=des:qos mandatory remote sendrecv a=rtpmap:97 AMR a=fmtp:97 mode-set=0,2,5,7; mode-change-period=2


102

a=rtpmap:96 telephone-event a=maxptime:20

P-Charging-Vector: P-CSCF 在此头域中增加 GPRS 访问网络的信息，这些信息由 S-CSCF 保存和删

除。



[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 From: To: Call-ID: CSeq: Content-Type: Content-Length: v= o= s= c= t= m= m= b= a= a= a= a= a= a= a= a=

180 Ringing (S-S#3 to MO)



PRACK (MO to S-S#3)


[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 Max-Forwards: 69 P-Access-Network-Info: 3GPP-UTRAN-TDD; utran-cell-id-3gpp=234151D0FCE11 Route: <sip:scscf1.home1.net;lr> From: <sip:[email protected]>;tag=171828 To: <tel:+1-212-555-2222>;tag=314159 Call-ID: cb03a0s09a2sdfglkj490333 Cseq: 130 PRACK RAck: 9022 127 INVITE Content-Length: 0


103







ACK (MO to S-S#3)

ACK sip:mgcf1.home1.net SIP/2.0 Via: SIP/2.0/UDP pcscf1.home1.net;branch=z9hG4bK431h23.1, SIP/2.0/UDP

[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 Max-Forwards: 69 Route: <sip:scsf1.home1.net;lr> From: <sip:[email protected]>;tag=171828 To: <tel:+1-212-555-2222>;tag=314159 Call-ID: cb03a0s09a2sdfglkj490333 Cseq: 127 ACK Content-Length: 0

6.5.2.2.7 不同域间会话，电路交换网用户做被叫


104

4. INVITE

22. 180 (Ringing)

S-CSCF MGCF


14. PRACK

26. PRACK

30. 200 (OK)

18. UPDATE

34. ACK

BGCF#1 BGCF#2

6. INVITE


1. INVITE


25. 180 (Ringing)

33. 200 (OK)

Terminating NetworkOriginating Network

24. 180 (Ringing)

32. 200 (OK)

2. 100 (Trying)

7. 100 (Trying)

5. 100 (Trying)

16. 200 (OK)17. 200 (OK)

21. 200 (OK)

28. 200 (OK)29. 200 (OK)


8. INVITE9. 100 (Trying)


15. PRACK

19. UPDATE

20. 200 (OK)

23. 180 (Ringing)

27. PRACK

31. 200 (OK)

35. ACK

Home Network

图41 不同域间会话，电路交换网用户做被叫

INVITE (MO to S-S#4)


[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 Max-Forwards: 69 Route: <sip:scscf1.home1.net;lr> Record-Route: <sip:pcscf1.home1.net;lr> P-Asserted-Identity: "John Doe" <tel:+1-212-555-1111> P-Access-Network-Info: 3GPP-UTRAN-TDD; utran-cell-id-3gpp=234151D0FCE11 P-Charging-Vector: icid-value="AyretyU0dm+6O2IrT5tAFrbHLso=023551024" Privacy: none From: <sip:[email protected]>;tag=171828 To: <tel:+1-212-555-2222> Call-ID: cb03a0s09a2sdfglkj490333 Cseq: 127 INVITE Require: precondition Supported: 100rel Contact: <sip:[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp> Allow: INVITE, ACK, CANCEL, BYE, PRACK, UPDATE, REFER, MESSAGE


105

Content-Type: application/sdp Content-Length: (…) v=0 o=- 2987933615 2987933615 IN IP6 5555::aaa:bbb:ccc:ddd s=- c=IN IP6 5555::aaa:bbb:ccc:ddd t=0 0 m=video 3400 RTP/AVP 98 99 b=AS:75 a=curr:qos local none a=curr:qos remote none a=des:qos mandatory local sendrecv a=des:qos none remote sendrecv a=rtpmap:98 H263 a=fmtp:98 profile-level-id=0 a=rtpmap:99 MP4V-ES m=audio 3456 RTP/AVP 97 96 b=AS:25.4 a=curr:qos local none a=curr:qos remote none a=des:qos mandatory local sendrecv a=des:qos none remote sendrecv a=rtpmap:97 AMR a=fmtp:97 mode-set=0,2,5,7; mode-change-period=2 a=rtpmap:96 telephone-event a=maxptime:20

100 Trying (S-S#4 to MO)



183 Session Progress (S-S#4 to MO)

SIP/2.0 183 Session Progress Via: SIP/2.0/UDP pcscf1.home1.net;branch=z9hG4bK431h23.1, SIP/2.0/UDP

[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 Record-Route: P-Asserted-Identity: P-Charging-Vector: icid-value="AyretyU0dm+6O2IrT5tAFrbHLso=023551024" Privacy: From: To: Call-ID: CSeq: Require: Contact: Allow: RSeq: Content-Type: Content-Length: v= o= s= c= t= m= m= b=


106

a= a= a= a= a= a= a= a= a=

PRACK (MO to S-S#4)


[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 Max-Forwards: 69 P-Access-Network-Info: 3GPP-UTRAN-TDD; utran-cell-id-3gpp=234151D0FCE11 Route: <sip:scscf1.home1.net;lr> From: <sip:[email protected]>;tag=171828 To: <tel:+1-212-555-2222>;tag=314159 Call-ID: cb03a0s09a2sdfglkj490333 Cseq: 128 PRACK Require: precondition RAck: 9021 127 INVITE Content-Length: 0




UPDATE (MO to S-S#4)

UPDATE sip:mgcf2.home2.net SIP/2.0 Via: SIP/2.0/UDP pcscf1.home1.net;branch=z9hG4bK431h23.1, SIP/2.0/UDP

[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 Max-Forwards: 69 P-Access-Network-Info: 3GPP-UTRAN-TDD; utran-cell-id-3gpp=234151D0FCE11 Route: <sip:scscf1.home1.net;lr> P-Charging-Vector: icid-value="AyretyU0dm+6O2IrT5tAFrbHLso=023551024";


From: <sip:[email protected]>;tag=171828 To: <tel:+1-212-555-2222>;tag=314159 Call-ID: cb03a0s09a2sdfglkj490333 Cseq: 129 UPDATE Content-Type: application/sdp Content-Length: (…) v=0 o=- 2987933615 2987933616 IN IP6 5555::aaa:bbb:ccc:ddd s=- c=IN IP6 5555::aaa:bbb:ccc:ddd t=0 0 m=video 0 RTP/AVP 98 99 m=audio 3456 RTP/AVP 97 96 b=AS:25.4 a=curr:qos local sendrecv


107

a=curr:qos remote none a=des:qos mandatory local sendrecv a=des:qos mandatory remote sendrecv a=rtpmap:97 AMR a=fmtp:97 mode-set=0,2,5,7; mode-change-period=2 a=rtpmap:96 telephone-event a=maxptime:20

P-Charging-Vector: P-CSCF 在此头域中增加 GPRS 访问网络的信息，这些信息由 S-CSCF 保存和删

除。



[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 From: To: Call-ID: CSeq: Content-Type: Content-Length: v= o= s= c= t= m= m= b= a= a= a= a= a= a= a= a=

180 Ringing (S-S#4 to MO)



PRACK (MO to S-S#4)


[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 Max-Forwards: 69 P-Access-Network-Info: 3GPP-UTRAN-TDD; utran-cell-id-3gpp=234151D0FCE11 Route: <sip:scscf1.home1.net;lr> From: <sip:[email protected]>;tag=171828 To: <tel:+1-212-555-2222>;tag=314159


108

Call-ID: cb03a0s09a2sdfglkj490333 Cseq: 130 PRACK RAck: 9022 127 INVITE Content-Length: 0







ACK (MO to S-S#4)

ACK sip:mgcf2.home2.net SIP/2.0 Via: SIP/2.0/UDP pcscf1.home1.net;branch=z9hG4bK431h23.1, SIP/2.0/UDP

[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 Max-Forwards: 69 Route: <sip:scscf1.home1.net;lr> From: <sip:[email protected]>;tag=171828 To: <tel:+1-212-555-2222>;tag=314159 Call-ID: cb03a0s09a2sdfglkj490333 Cseq: 127 ACK Content-Length: 0

6.5.2.3 MT 流程 6.5.2.3.1 IMS 域用户漫游


109

4. INVITE

25. 180 (Ringing)26. 180 (Ringing)

S-CSCF P-CSCF

7. 100 (Trying)


12. PRACK

17. 200 (OK)

28. PRACK

31. 200 (OK)

34. 200 (OK)

36. 200 (OK)

19. UPDATE

UE#2

6. INVITE

38. ACK

1. INVITE


27. 180 (Ringing)

37. 200 (OK)



2. 100 (Trying)

5. 100 (Trying)


13. PRACK14. PRACK15. 200 (OK)

16. 200 (OK)

21. UPDATE22. 200 (OK)

24. 200 (OK)

29. PRACK30. PRACK

32. 200 (OK)33. 200 (OK)

39. ACK40. ACK

20. UPDATE

23. 200 (OK)

Home Network Visited Network



图42 IMS 域用户漫游

INVITE (S-CSCF to P-CSCF)

INVITE sip:[5555::eee:fff:aaa:bbb]:8805;comp=sigcomp SIP/2.0 Via: SIP/2.0/UDP scscf2.home2.net;branch=z9hG4bK764z87.1, SIP/2.0/UDP

icscf2_s.home2.net;branch=z9hG4bK871y12.1, SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1, SIP/2.0/UDP pcscf1.visited1.net;branch=z9hG4bK240f34.1, SIP/2.0/UDP [5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7

Max-Forwards: 66 Route: <sip:pcscf2.visited2.net;lr> Record-Route: <sip:scscf2.home2.net;lr>, <sip:scscf1.home1.net;lr>,

<sip:pcscf1.visited1.net;lr> P-Asserted-Identity: P-Charging-Vector: icid-value="AyretyU0dm+6O2IrT5tAFrbHLso=023551024" Privacy: From: To: Call-ID: Cseq: Require: Supported: Contact: Allow: P-Called-Party-ID: <sip:[email protected]> Content-Type: Content-Length: (…) v= o= s= c= t=


110

m= b= a= a= a= a= a= a= a= m= b= a= a= a= a= a= a= a= a=

Route:从注册时保存的 Paht 头域中取值。

P-Called-Party-ID:被叫 URL 以及参数。

Via:/Record-Route:S-CSCF 添加。

100 Trying (P-CSCF to S-CSCF)

SIP/2.0 100 Trying Via: SIP/2.0/UDP scscf2.home2.net;branch=z9hG4bK764z87.1, SIP/2.0/UDP



183 Session Progress(P-CSCF to S-CSCF)

SIP/2.0 183 Session Progress Via: SIP/2.0/UDP scscf2.home2.net;branch=z9hG4bK764z87.1, SIP/2.0/UDP

icscf2_s.home2.net;branch=z9hG4bK871y12.1, SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1, SIP/2.0/UDP pcscf1.visited1.net;branch=z9hG4bK240f34.1, SIP/2.0/UDP [5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7)

Record-Route: <sip:pcscf2.visited2.net;lr>, <sip:scscf2.home2.net;lr>, <sip:scscf1.home1.net;lr>, <sip:pcscf1.visited1.net;lr>

P-Asserted-Identity: "John Smith" <sip:[email protected]> P-Access-Network-Info: P-Charging-Vector: icid-value="AyretyU0dm+6O2IrT5tAFrbHLso=023551024" Privacy: From: To: Call-ID: CSeq: Require: Contact: Allow: RSeq: Content-Type: Content-Length: v= o= s= c=


111

t= m= b= a= a= a= a= a= a= a= a= m= b= a= a= a= a= a= a= a= a= a=

Record-Route:P-CSCF 重新改写了 Record-Route 头，在它自己的 SIP URI 中增加了在安全一致性

协商中确定的端口号和 comp=sigcomp 参数。

P-Asserted-Identity:P-CSCF 插入用户默认的 SIP URI。

P-Access-Network-Info:包含从 UE 得到的信息。

PRACK (S-CSCF to P-CSCF)

PRACK sip:[5555::eee:fff:aaa:bbb]:8805;comp=sigcomp SIP/2.0 Via: SIP/2.0/UDP scscf2.home2.net;branch=z9hG4bK764z87.1, SIP/2.0/UDP


Max-Forwards: 67 Route: <sip:pcscf2.visited2.net;lr> From: To: Call-ID: Cseq: Require: RAck: Content-Type: Content-Length: v= o= s= c= t= m= b= a= a= a= a= a= a= m= b= a= a= a= a= a= a= a=


112

a=

200 OK (P-CSCF to S-CSCF)

SIP/2.0 200 OK Via: SIP/2.0/UDP scscf2.home2.net;branch=z9hG4bK764z87.1, SIP/2.0/UDP


P-Access-Network-Info: From: To: Call-ID: CSeq: Content-Type: Content-Length: v= o= s= c= t= m= b= a= a= a= a= a= a= a= m= b= a= a= a= a= a= a= a= a= a=

UPDATE (S-CSCF to P-CSCF)

UPDATE sip:[5555::eee:fff:aaa:bbb]:8805;comp=sigcomp SIP/2.0 Via: SIP/2.0/UDP scscf2.home2.net;branch=z9hG4bK764z87.1, SIP/2.0/UDP


Max-Forwards: 67 Route: <sip:pcscf2.visited2.net;lr> From: To: Call-ID: Cseq: Contact: Content-Type: Content-Length: v= o= s= c= t= m= b=


113

a= a= a= a= a= a= m= b= a= a= a= a= a= a= a= a=




P-Access-Network-Info: From: To: Call-ID: CSeq: Content-Type: Content-Length: v= o= s= c= t= m= b= a= a= a= a= a= a= m= b= a= a= a= a= a= a= a= a=

180 Ringing (P-CSCF to S-CSCF)

SIP/2.0 180 Ringing Via: SIP/2.0/UDP scscf2.home2.net;branch=z9hG4bK764z87.1, SIP/2.0/UDP


Record-Route: <sip:pcscf2.visited2.net;lr>,<sip:scscf2.home2.net;lr>, <sip:scscf1.home1.net;lr>, <sip:pcscf1.visited1.net;lr>

P-Access-Network-Info:


114

P-Charging-Vector: icid-value="AyretyU0dm+6O2IrT5tAFrbHLso=023551024"; ggsn=[5555::d6d:c7c:b8b:a9a]; auth-token=2A96B3AF30D1; pdp-info="pdp-item=1; pdp-sig=no; gcid=A93D238CAF; flow-id=({1,1},{1,2}), pdp-item=2; pdp-sig=no; gcid=F312D5E3BC; flow-id=({2,1},{2,2})"







Max-Forwards: 67 Route: <sip:pcscf2.visited2.net;lr> From: To: Call-ID: Cseq: RAck: Content-Length:




P-Access-Network-Info: P-Charging-Vector: icid-value="AyretyU0dm+6O2IrT5tAFrbHLso=023551024";

ggsn=[5555::d6d:c7c:b8b:a9a]; auth-token=2A96B3AF30D1; pdp-info="pdp-item=1; pdp-sig=no; gcid=A93D238CAF; flow-id=({1,1},{1,2}), pdp-item=2; pdp-sig=no; gcid=F312D5E3BC; flow-id=({2,1},{2,2})"





Record-Route: <sip:pcscf2.visited2.net;lr>, <sip:scscf2.home2.net;lr>, <sip:scscf1.home1.net;lr>, <sip:pcscf1.visited1.net;lr>

P-Access-Network-Info: From: To: Call-ID: CSeq: Contact:


115

Allow: Content-Length:




ACK (S-CSCF to P-CSCF)

ACK sip:[5555::eee:fff:aaa:bbb]:8805;comp=sigcomp SIP/2.0 Via: SIP/2.0/UDP scscf2.home2.net;branch=z9hG4bK764z87.1, SIP/2.0/UDP


Max-Forwards: 67 Route: <sip:pcscf2.visited2.net;lr> From: To: Call-ID: Cseq: Content-Length:

6.5.2.3.2 UE 检测失败/资源失败（漫游）

4. INVITE


S-CSCF P-CSCF

7. 100 (Trying)


12. PRACK

17. 200 (OK)

28. PRACK

31. 200 (OK)

34. xxx (Error)

37. xxx (Error)

19. UPDATE

UE#2

6. INVITE

40. ACK

1. INVITE


27. 180 (Ringing)

39. xxx (Error)




2. 100 (Trying)

5. 100 (Trying)


13. PRACK14. PRACK

15. 200 (OK)16. 200 (OK)

21. UPDATE22. 200 (OK)

24. 200 (OK)

29. PRACK30. PRACK

32. 200 (OK)33. 200 (OK)

38. ACK

35. ACK

20. UPDATE

23. 200 (OK)



图43 UE 检测失败/资源失败（漫游）

xxx Error (P-CSCF to S-CSCF)



SIP/2.0 486 Busy Here


116

Via: SIP/2.0/UDP scscf2.home2.net;branch=z9hG4bK764z87.1, SIP/2.0/UDP icscf2_s.home2.net;branch=z9hG4bK871y12.1, SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1, SIP/2.0/UDP pcscf1.home1.net;branch=z9hG4bK431h23.1, SIP/2.0/UDP [5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7

P-Access-Network-Info: From: To: Call-ID: CSeq: Retry-After: 3600 Content-Length: 0



ACK sip:[5555::eee:fff:aaa:bbb]:8805;comp=sigcomp SIP/2.0 Via: SIP/2.0/UDP scscf2.home2.net;branch=z9hG4bK764z87.1 Route: <sip:pcscf2.visited2.net;lr> From: To: Call-ID: CSeq: 127 ACK Content-Length: 0

6.5.2.3.3 主叫侧失败（漫游）

4 . IN V IT E

2 5 . 1 8 0 (R in g in g )2 6 . 1 8 0 (R in g in g )

S -C S C F P -C S C F

7 . 1 0 0 (T ry in g )

1 0 . 1 8 3 (S e s s io nP ro g re s s )

1 2 . P R A C K

1 7 . 2 0 0 (O K )

2 8 . P R A C K

3 1 . 2 0 0 (O K )

4 1 . 4 8 7 (R e q u e s tT e rm in a te d )


1 9 . U P D A T E

U E # 2

6 . IN V IT E

4 6 . A C K

1 . IN V IT E

1 1 . 1 8 3 (S e s s io nP ro g re s s )

2 7 . 1 8 0 (R in g in g )


1 8 . R e s o u rc eR e s e rva tio n

3 . E va lu a tio n o f in it ia lf ilte r c r ite ria s

9 . A u th o rize Q o S R e s o u rc e s

2 . 1 0 0 (T ry in g )

5 . 1 0 0 (T ry in g )

8 . 1 8 3 (S e s s io nP ro g re s s )

1 3 . P R A C K1 4 . P R A C K1 5 . 2 0 0 (O K )

1 6 . 2 0 0 (O K )

2 1 . U P D A T E2 2 . 2 0 0 (O K )

2 4 . 2 0 0 (O K )

2 9 . P R A C K3 0 . P R A C K

3 2 . 2 0 0 (O K )3 3 . 2 0 0 (O K )

4 4 . A C K

4 2 . A C K

2 0 . U P D A T E

2 3 . 2 0 0 (O K )

H o m e N e tw o rk V is ite d N e tw o rk

3 4 . C A N C E L

3 6 . C A N C E L

3 9 . C A N C E L

4 0 . 2 0 0 (O K )

3 7 . 2 0 0 (O K )

3 5 . 2 0 0 (O K )

3 8 . R e vo k e Q o S R e s o u rc e s

图44 主叫侧失败（漫游）


117

CANCEL (S-CSCF to P-CSCF)

CANCEL sip:[5555::eee:fff:aaa:bbb]:8805;comp=sigcomp SIP/2.0 Via: SIP/2.0/UDP scscf2.home2.net;branch=z9hG4bK764z87.1 Route: <sip:pcscf2.visited2.net;lr> From: To: Call-ID: Cseq: Content-Length:


SIP/2.0 200 OK Via: SIP/2.0/UDP scscf2.home2.net;branch=z9hG4bK764z87.1 From: To: Call-ID: CSeq: Content-Length: 0

487 请求终止 (P-CSCF to S-CSCF)

SIP/2.0 487 Request Terminated Via: SIP/2.0/UDP scscf2.home2.net;branch=z9hG4bK764z87.1, SIP/2.0/UDP

icscf2_s.home2.net;branch=z9hG4bK871y12.1, SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1, SIP/2.0/UDP pcscf1.home1.net;branch=z9hG4bK431h23.1, SIP/2.0/UDP [5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7

P-Access-Network-Info: 3GPP-UTRAN-TDD; utran-cell-id-3gpp=234151D0FCE11 From: To: Call-ID: CSeq: Retry-After: 3600 Content-Length: 0


ACK sip:[5555::eee:fff:aaa:bbb]:8805;comp=sigcomp SIP/2.0 Via: SIP/2.0/UDP scscf2.home2.net;branch=z9hG4bK764z87.1 Route: <sip:pcscf2.visited2.net;lr> From: To: Call-ID: CSeq: 127 ACK Content-Length: 0

6.5.2.3.4 IMS 用户，未漫游


118

Home Network

4. INVITE


S-CSCF P-CSCF

7. 100 (Trying)


12. PRACK

17. 200 (OK)

28. PRACK

31. 200 (OK)

34. 200 (OK)

36. 200 (OK)

19. UPDATE

UE#2

6. INVITE

38. ACK

1. INVITE


27. 180 (Ringing)

37. 200 (OK)




2. 100 (Trying)

5. 100 (Trying)


13. PRACK 14. PRACK

15. 200 (OK)16. 200 (OK)

21. UPDATE22. 200 (OK)

24. 200 (OK)

29. PRACK30. PRACK

32. 200 (OK)33. 200 (OK)

39. ACK40. ACK

23. 200 (OK)

20. UPDATE

35. Approval of QoS Commit

图45 IMS 域用户，未漫游




Max-Forwards: 66 Route: <sip:pcscf2.home2.net;lr> Record-Route: <sip:scscf2.home2.net;lr>, <sip:scscf1.home1.net;lr>, <sip:pcscf1.home1.net;lr> P-Asserted-Identity: P-Charging-Vector: icid-value="AyretyU0dm+6O2IrT5tAFrbHLso=023551024" Privacy: From: To: Call-ID: Cseq: Require: Supported: Contact: Allow: P-Called-Party-ID: <sip:[email protected]> Content-Type: Content-Length: v= o=


119

s= c= t= m= b= a= a= a= a= a= a= a= m= b= a= a= a= a= a= a= a= a=

Route:从注册时保存的 Paht 头域中取值。

P-Called-Party-ID:被叫 URL 以及参数。

Via:/Record-Route:S-CSCF 添加。





183 Session Progress (P-CSCF to S-CSCF)

SIP/2.0 183 Session Progress Via: SIP/2.0/UDP scscf2.home2.net;branch=z9hG4bK764z87.1, SIP/2.0/UDP

icscf2_s.home2.net;branch=z9hG4bK871y12.1, SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1, SIP/2.0/UDP pcscf1.home1.net;branch=z9hG4bK431h23.1, SIP/2.0/UDP [5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7)

Record-Route: <sip:pcscf2.home2.net;lr>, <sip:scscf2.home2.net;lr>, <sip:scscf1.home1.net;lr>, <sip:pcscf1.home1.net;lr>

P-Access-Network-Info: P-Asserted-Identity: "John Smith" <sip:[email protected]> P-Charging-Vector: icid-value="AyretyU0dm+6O2IrT5tAFrbHLso=023551024" Privacy: From: To: Call-ID: CSeq: Require: Contact: Allow: RSeq: Content-Type: Content-Length:


120

v= o= s= c= t= m= b= a= a= a= a= a= a= a= a= m= b= a= a= a= a= a= a= a= a= a=


P-Asserted-Identity:P-CSCF 插入用户默认的 SIP URI。






Max-Forwards: 67 Route: <sip:pcscf2.home2.net;lr> From: To: Call-ID: Cseq: Require: RAck: Content-Type: Content-Length: v= o= s= c= t= m= b= a= a= a= a= a= a= m= b= a= a=


121

a= a= a= a= a= a=




P-Access-Network-Info: From: To: Call-ID: CSeq: Content-Type: Content-Length: v= o= s= c= t= m= b= a= a= a= a= a= a= a= m= b= a= a= a= a= a= a= a= a= a=

UPDATE (S-CSCF to P-CSCF)

UPDATE sip:[5555::eee:fff:aaa:bbb]:8805;comp=sigcomp SIP/2.0 Via: SIP/2.0/UDP scscf2.home2.net;branch=z9hG4bK764z87.1, SIP/2.0/UDP


Max-Forwards: 67 Route: <sip:pcscf2.home2.net;lr> From: To: Call-ID: Cseq: Contact: Content-Type: Content-Length: v= o=


122

s= c= t= m= b= a= a= a= a= a= a= m= b= a= a= a= a= a= a= a= a=




P-Access-Network-Info: From: To: Call-ID: CSeq: Content-Type: Content-Length: v= o= s= c= t= m= b= a= a= a= a= a= a= m= b= a= a= a= a= a= a= a= a=

180 Ringing (P-CSCF to S-CSCF)

SIP/2.0 180 Ringing


123

Via: SIP/2.0/UDP scscf2.home2.net;branch=z9hG4bK764z87.1, SIP/2.0/UDP icscf2_s.home2.net;branch=z9hG4bK871y12.1, SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1, SIP/2.0/UDP pcscf1.home1.net;branch=z9hG4bK431h23.1, SIP/2.0/UDP [5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7


P-Charging-Vector: icid-value="AyretyU0dm+6O2IrT5tAFrbHLso=023551024"; ggsn=[5555::d6d:c7c:b8b:a9a]; pdp-sig=no; gcid=309685742; auth-token=86243614; flow-id=3







Max-Forwards: 67 Route: <sip:pcscf2.home2.net;lr> From: To: Call-ID: Cseq: RAck: Content-Length:




P-Access-Network-Info: P-Charging-Vector: icid-value="AyretyU0dm+6O2IrT5tAFrbHLso=023551024";

ggsn=[5555::d6d:c7c:b8b:a9a]; auth-token=2A96B3AF30D1; pdp-info="pdp-item=1; pdp-sig=no; gcid=A93D238CAF; flow-id=({1,1},{1,2}), pdp-item=2; pdp-sig=no; gcid=F312D5E3BC; flow-id=({2,1},{2,2})"



SIP/2.0 200 OK Via: SIP/2.0/UDP scscf2.home2.net;branch=z9hG4bK764z87.1, SIP/2.0/UDP icscf2_s.home2.net,

SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1, SIP/2.0/UDP pcscf1.home1.net;branch=z9hG4bK431h23.1, SIP/2.0/UDP [5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7



124

P-Access-Network-Info: From: To: Call-ID: CSeq: Contact: Allow: Content-Length:




ACK sip:[5555::eee:fff:aaa:bbb]:8805;comp=sigcomp SIP/2.0 Via: SIP/2.0/UDP scscf2.home2.net;branch=z9hG4bK764z87.1, SIP/2.0/UDP


Max-Forwards: 67 Route: <sip:pcscf2.home2.net;lr> From: To: Call-ID: Cseq: Content-Length:

6.5.2.3.5 电路交换网用户做被叫

MGWMGCF

Terminating Network

3. H.248 interaction to createconnection

2. 100 Trying


8. 200 OK

9. H.248 interaction to modifyconnection to reserve

resources


11. UPDATE

12. 200 OK

15. 180

16. PRACK

17. 200 OK

14. ACM / CPG

4. IAM

1. INVITE

7. PRACK

13. COT/IAM

20. 200 OK

18. ANM

19. H.248 interaction tomodify connection to start

media flow

21. ACK

PSTN/CS domain

5. Bearer related negotiation (in case BICC is used)

图46 电路交换网用户做被叫


125

INVITE (S-S to CS-T)



Max-Forwards: 67 Record-Route: <sip:scscf1.home1.net;lr>, <sip:pcscf1.home1.net;lr> P-Asserted-Identity: "John Doe" <tel:+1-212-555-1111> P-Charging-Vector: icid-value="AyretyU0dm+6O2IrT5tAFrbHLso=023551024" P-Charging-Function-Addresses: ccf=[5555::b99:c88:d77:e66]; ccf=[5555::a55:b44:c33:d22];

ecf=[5555::1ff:2ee:3dd:4cc]; ecf=[5555::6aa:7bb:8cc:9dd] Privacy: none From: <sip:[email protected]>;tag=171828 To: <tel:+1-212-555-2222> Call-ID: cb03a0s09a2sdfglkj490333 Cseq: 127 INVITE Require: precondition Supported: 100rel Contact: <sip:[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp> Allow: INVITE, ACK, CANCEL, BYE, PRACK, UPDATE, REFER, MESSAGE Content-Type: application/sdp Content-Length: (…) v=0 o=- 2987933615 2987933615 IN IP6 5555::aaa:bbb:ccc:ddd s=- c=IN IP6 5555::aaa:bbb:ccc:ddd t=0 0 m=video 3400 RTP/AVP 98 99 b=AS:75 a=curr:qos local none a=curr:qos remote none a=des:qos mandatory local sendrecv a=des:qos none remote sendrecv a=rtpmap:98 H263 a=fmtp:98 profile-level-id=0 a=rtpmap:99 MP4V-ES m=audio 3456 RTP/AVP 97 96 b=AS:25.4 a=curr:qos local none a=curr:qos remote none a=des:qos mandatory local sendrecv a=des:qos none remote sendrecv a=rtpmap:97 AMR a=fmtp:97 mode-set=0,2,5,7; mode-change-period=2 a=rtpmap:96 telephone-event a=maxptime:20

P-Charging-Vector:S-CSCF 将此头域传给 MGCF 用于计费，如果 S-CSCF 和 MGCF 属于不同域，则包

含 orig-ioi，而 183 Session Progress 响应中包含 term-ioi。

P-Charging-Function-Addresses:当 S-CSCF 和 MGCF 在同一个域中时，S-CSCF 插入此头域给 MGCF

提供计费功能地址。如果不在同一个域，没有此头域。

100 Trying (CS-T to S-S)





126

Content-Length: 0

183 Session Progress (CS-T to S-S)



Record-Route: <sip:scscf1.home1.net;lr>, <sip:pcscf1.home1.net;lr> P-Asserted-Identity: <tel:+1-212-555-2222> P-Charging-Vector: Privacy: none From: To: <tel:+1-212-555-2222>;tag=314159 Call-ID: CSeq: Require: 100rel Contact: <sip:mgcf1.home1.net> Allow: INVITE, ACK, CANCEL, BYE, PRACK, UPDATE RSeq: 9021 Content-Type: application/sdp Content-Length: (…) v=0 o=- 2987933623 2987933623 IN IP6 5555::eee:fff:aaa:bbb s=- c=IN IP6 5555::eee:fff:aaa:bbb t=0 0 m=video 0 RTP/AVP 98 99 m=audio 6544 RTP/AVP 97 96 b=AS:25.4 a=curr:qos local none a=curr:qos remote none a=des:qos mandatory local sendrecv a=des:qos none remote sendrecv a=conf:qos remote sendrecv a=rtpmap:97 AMR a=fmtp:97 mode-set=0,2,5,7; mode-change-period=2 a=rtpmap:96 telephone-event a=maxptime:20

PRACK (S-S to CS-T)




200 OK (CS-T to S-S)





127

UPDATE (S-S to CS-T)

UPDATE sip:mgcf1.home1.net SIP/2.0 Via: SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1, SIP/2.0/UDP


Max-Forwards: 68 From: <sip:[email protected]>;tag=171828 To: <tel:+1-212-555-2222>;tag=314159 Call-ID: cb03a0s09a2sdfglkj490333 Cseq: 129 UPDATE Content-Type: application/sdp Content-Length: (…) v=0 o=- 2987933615 2987933616 IN IP6 5555::aaa:bbb:ccc:ddd s=- c=IN IP6 5555::aaa:bbb:ccc:ddd t=0 0 m=video 0 RTP/AVP 98 99 m=audio 3456 RTP/AVP 97 96 b=AS:25.4 a=curr:qos local sendrecv a=curr:qos remote none a=des:qos mandatory local sendrecv a=des:qos mandatory remote sendrecv a=rtpmap:97 AMR a=fmtp:97 mode-set=0,2,5,7; mode-change-period=2 a=rtpmap:96 telephone-event a=maxptime:20




From: To: Call-ID: CSeq: Content-Type: application/sdp Content-Length: (…) v=0 o=- 2987933623 2987933623 IN IP6 5555::aaa:bbb:ccc:ddd s=- c=IN IP6 5555::aaa:bbb:ccc:ddd t=0 0 m=video 0 RTP/AVP 98 99 m=audio 6544 RTP/AVP 97 96 b=AS:25.4 a=curr:qos local sendrecv a=curr:qos remote sendrecv a=des:qos mandatory local sendrecv a=des:qos mandatory remote sendrecv a=rtpmap:97 AMR a=fmtp:97 mode-set=0,2,5,7; mode-change-period=2 a=rtpmap:96 telephone-event a=maxptime:20

180 (CS-T to S-S)

SIP/2.0 180 Ringing


128

Via: SIP/2.0/UDP bgcf1.home1.net;branch=z9hG4bK6546q2.1, SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1, SIP/2.0/UDP pcscf1.home1.net;branch=z9hG4bK431h23.1, SIP/2.0/UDP [5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7

Record-Route: <sip:scscf1.home1.net;lr>, <sip:pcscf1.home1.net;lr> Require: 100rel From: To: Call-ID: CSeq: 127 INVITE Contact: <sip:mgcf1.home1.net> Allow: INVITE, ACK, CANCEL, BYE, PRACK, UPDATE RSeq: 9022 Content-Length: 0

PRACK (S-S to CS-T)








200 OK (CS-T to S-S



Record-Route: <sip:scscf1.home1.net;lr>, <sip:pcscf1.home1.net;lr> From: To: Call-ID: CSeq: 127 INVITE Contact: <sip:mgcf1.home1.net> Allow: INVITE, ACK, CANCEL, BYE, PRACK, UPDATE Content-Length: 0

ACK (S-S to CS-T)

ACK sip:mgcf1.home1.net SIP/2.0 Via: SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1, SIP/2.0/UDP


Max-Forwards: 68 From:


129

To: Call-ID: Cseq: 127 ACK Content-Length: 0

6.5.2.3.6 IMS 用户漫游，归属域没有独立 I-CSCF，用户忙、不能或者不愿意应答来话

4. INVITE

S-CSCF P-CSCF

9. 486 Busy Here

UE#2

6. INVITE

1. INVITE

3. Evaluation of initial filtercriterias

2. 100 Trying

5. 100 Trying

7. 486 Busy Here


8. ACK

10. ACK

11. 486 Busy Here12. ACK

图47 IMS 域用户漫游，归属域没有独立 I-CSCF，用户忙、不能或者不愿意应答来话




Max-Forwards: 66 Route: <sip:pcscf2.visited2.net;lr> Record-Route: <sip:scscf2.home2.net;lr>, <sip:scscf1.home1.net;lr>, <sip:pcscf1.home1.net;lr> P-Asserted-Identity: P-Charging-Vector: icid-value="AyretyU0dm+6O2IrT5tAFrbHLso=023551024" Privacy: From: To: Call-ID: Cseq: Require: Supported: Contact: Allow: P-Called-Party-ID: <sip:[email protected]> Content-Type: Content-Length: (…) v= o= s= c= t= m= b= a= a=


130

a= a= a= a= a= m= b= a= a= a= a= a= a= a= a=

P-Called-Party-ID:被叫端 URI 及其参数。

Route:从 Path 头域中取值。

Via:, Record-Route:S-CSCF 添加。





486 Busy Here (P-CSCF to S-CSCF)

SIP/2.0 486 Busy Here Via: SIP/2.0/UDP scscf2.home1.net;branch=z9hG4bK764z87.1, SIP/2.0/UDP

icscf2_s.home1.net;branch=z9hG4bK871y12.1, SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1, SIP/2.0/UDP pcscf1.home1.net;branch=z9hG4bK431h23.1, SIP/2.0/UDP [5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7)

P-Access-Network-Info: From: To: <tel:+1-212-555-2222>;tag=314159 Call-ID: CSeq: Retry-After: 3600 Content-Length: 0



ACK sip:[5555::eee:fff:aaa:bbb]:8805;comp=sigcomp SIP/2.0 Via: SIP/2.0/UDP scscf2.home1.net;branch=z9hG4bK764z87.1 Max-Forwards: 70 From: Route: <sip:pcscf2.visited2.net;lr> To: Call-ID: CSeq: Content-Length: 0

6.5.2.3.7 IMS 用户漫游，归属域没有独立 I-CSCF，S-CSCF 拒绝服务


131

S-CSCF P-CSCF UE#2

1.


Home NetworkVisited

Network

4. 403Forbidden

5. ACK

1. INVITE

2. 100Trying

图48 IMS 域用户漫游，归属域没有独立 I-CSCF，S-CSCF 拒绝服务

INVITE (S-S to MT#1e)



Max-Forwards: 67 Route: <sip:scscf2.home2.net;lr> Record-Route: <sip:scscf1.home1.net;lr>, <sip:pcscf1.home1.net;lr> P-Asserted-Identity: "John Doe" <sip:[email protected]>, <tel:+1-212-555-1111> P-Charging-Vector: icid-value="AyretyU0dm+6O2IrT5tAFrbHLso=023551024"; orig-ioi=home1.net Privacy: none From: <sip:[email protected]>;tag=171828 To: <tel:+1-212-555-2222> Call-ID: cb03a0s09a2sdfglkj490333 Cseq: 127 INVITE Require: precondition Supported: 100rel Contact: <sip:[5555:aaa:bbb:ccc:ddd]:1357;comp=sigcomp> Allow: INVITE, ACK, CANCEL, BYE, PRACK, UPDATE, REFER, MESSAGE Content-Type: application/sdp Content-Length: (…) v=0 o=- 2987933615 2987933615 IN IP6 5555::aaa:bbb:ccc:ddd s=- c=IN IP6 5555::aaa:bbb:ccc:ddd t=0 0 m=video 3400 RTP/AVP 98 99 b=AS:75 a=curr:qos local none a=curr:qos remote none a=des:qos mandatory local sendrecv a=des:qos none remote sendrecv a=rtpmap:98 H263 a=fmtp:98 profile-level-id=0 a=rtpmap:99 MP4V-ES m=audio 3456 RTP/AVP 97 96 b=AS:25.4 a=curr:qos local none a=curr:qos remote none a=des:qos mandatory local sendrecv a=des:qos none remote sendrecv a=rtpmap:97 AMR a=fmtp:97 mode-set=0,2,5,7; mode-change-period=2


132

a=rtpmap:96 telephone-event a=maxptime:20

100 Trying (MT#1e to S-S)




403 Forbidden (MT#1e to S-S)

SIP/2.0 403 Forbidden Via: SIP/2.0/UDP icscf2_s.home2.net;branch=z9hG4bK871y12.1, SIP/2.0/UDP

scscf1.home1.net;branch=z9hG4bK332b23.1, SIP/2.0/UDP pcscf1.home1.net;branch=z9hG4bK431h23.1, SIP/2.0/UDP [5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7)

From: To: <tel:+1-212-555-2222>;tag=314159 Call-ID: CSeq: Content-Length: 0

ACK (S-S to MT#1e)

ACK sip:[email protected] SIP/2.0 Via: SIP/2.0/UDP icscf2_s.home2.net;branch=z9hG4bK871y12.1, SIP/2.0/UDP

scscf1.home1.net;branch=z9hG4bK332b23.1 Max-Forwards: 70 Route: <sip:scscf2.home2.net;lr> From: To: Call-ID: CSeq: Content-Length: 0

6.5.2.3.8 被叫用户未注册，未签约未注册业务

4. INVITE

S-CSCF#1 S-CSCF#2

10. ACK

I-CSCF HSS

7. 404 (Not Found)

1. INVITE

9. 404 (Not Found)

Home Network#2Originating Network

2. 100 (Trying)

5. 100 (Trying)

8. ACK

Home Network#1


3. Evaluate FilterCriteria

图49 被叫用户未注册，未签约未注册业务


133




Max-Forwards: 68 Record-Route: <sip:scscf1.home1.net;lr>, <sip:pcscf1.visited1.net;lr> P-Asserted-Identity: "John Doe" <sip:[email protected]>, <tel:+1-212-555-1111> P-Charging-Vector: icid-value="AyretyU0dm+6O2IrT5tAFrbHLso=023551024"; orig-ioi=home1.net Privacy: From: To: Call-ID: Cseq: Require: Supported: Contact: Allow: Content-Type: Content-Length: (…) v= o= s= c= t= m= b= a= a= a= a= a= a= a= m= b= a= a= a= a= a= a= a= a=





404 Not Found (I-CSCF to S-CSCF)

SIP/2.0 404 Not Found Via: SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1, SIP/2.0/UDP

pcscf1.visited1.net;branch=z9hG4bK240f34.1, SIP/2.0/UDP [5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7)


134



ACK sip:[email protected] SIP/2.0 Via: SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1 Max-Forwards: 70 From: To: Call-ID: Cseq: Content-Length:

6.5.2.3.9 被叫用户未注册，签约未注册业务

4. INVITE

S-CSCF#1 S-CSCF#2I-CSCF HSS

1. INVITE

Home Network#2Originating Network

2. 100 (Trying)

5. 100 (Trying)

Home Network#1

6. Cx: User Locationquery

7. INVITE

8. 100 (Trying)

10. Cx: User Profiledownload


9. Cx: S-CSCFregistration

notification procedure


图50 被叫用户未注册，签约未注册业务




Max-Forwards: 68 Record-Route: <sip:scscf1.home1.net;lr>, <sip:pcscf1.visited1.net;lr> P-Asserted-Identity: "John Doe" <sip:[email protected], <tel:+1-212-555-1111> P-Charging-Vector: icid-value="AyretyU0dm+6O2IrT5tAFrbHLso=023551024"; orig-ioi=home1.net Privacy: From: To: Call-ID: Cseq: Require: Supported: Contact: Allow:


135

Content-Type: Content-Length: (…) v= o= s= c= t= m= b= a= a= a= a= a= a= a= m= b= a= a= a= a= a= a= a= a=







scscf1.home1.net;branch=z9hG4bK332b23.1, SIP/2.0/UDP pcscf1.visited1.net;branch=z9hG4bK240f34.1, SIP/2.0/UDP [5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7)

Max-Forwards: 67 Route: <sip:scscf2.home2.net;lr> Record-Route: <sip:scscf1.home1.net;lr>, <sip:pcscf1.visited1.net;lr> P-Asserted-Identity: P-Charging-Vector: Privacy: From: To: Call-ID: Cseq: Require: Supported: Contact: Allow: Content-Type: Content-Length: v= o= s=


136

c= t= m= b= a= a= a= a= a= a= a= m= b= a= a= a= a= a= a= a= a=





6.5.3 会话释放 6.5.3.1 移动终端发起呼叫释放


137

GPRS GPRS

UE#1 P-CSCF1 S-CSCF1 S-CSCF2 UE#2P-CSCF2

Visited1.net Home1.net Home2.net Visited2.net

1. BYE

7. BYE

6. BYE

5. BYE

9. BYE

10. 200 OK

15. 200 OK

13. 200 OK

16. 200 OK

14. 200 OK

4. Rem ove resource reservation

8. Removeresource

reservation

3. Rls.response

2.Release

PDP

12. Rls.response

11. Release

PDP

图51 移动终端发起呼叫释放流程

BYE (P-CSCF to S-CSCF)

BYE sip:[5555::eee:fff:aaa:bbb]:8805;comp=sigcomp SIP/2.0 Via: SIP/2.0/UDP pcscf1.visited1.net;branch=z9hG4bK240f34.1, SIP/2.0/UDP

[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 Max-Forwards: 69 P-Access-Network-Info: Route: <sip:scscf1.home1.net;lr>, <sip:scscf2.home2.net;lr>, <sip:pcscf2.visited2.net;lr> From: To: Call-ID: CSeq: Content-Length: 0


BYE (S-CSCF to S-CSCF)

BYE sip:[5555::eee:fff:aaa:bbb]:8805;comp=sigcomp SIP/2.0 Via: SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1, SIP/2.0/UDP


Max-Forwards: 68 Route: <sip:scscf2.home2.net;lr>, <sip:pcscf2.visited2.net;lr> From: To: Call-ID: CSeq: Content-Length:

BYE (S-CSCF to P-CSCF)

BYE sip:[5555::eee:fff:aaa:bbb]:8805;comp=sigcomp SIP/2.0


138

Via: SIP/2.0/UDP scscf2.home2.net;branch=z9hG4bK764z87.1, SIP/2.0/UDP scscf1.home1.net;branch=z9hG4bK332b23.1, SIP/2.0/UDP pcscf1.visited1.net;branch=z9hG4bK240f34.1, SIP/2.0/UDP [5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7

Max-Forwards: 67 Route: <sip:pcscf2.visited2.net;lr> From: To: Call-ID: CSeq: Content-Length: 0




P-Access-Network-Info: From: To: Call-ID: CSeq: Content-Length: 0









6.6 Gm 接口本接口所有流程以 AKA 鉴权方式为准。

6.6.1 概述 Gm 接口是 UE 和 P-CSCF 之间的接口，主要负责注册和会话控制。

Gm 接口协议栈如下图所示：


139

SIP/SDP SIP/SDP

IP

TCP/UDP

SigComp

Gm UE P-CSCF

IP

TCP/UDP

SigComp

图52 Gm 接口协议栈

SIP/SDP:3GPP [24.229], [RFC3261] and [RFC2327]/[RFC3266] 以及相关的SIP扩展。

SigComp:[RFC3320]。

6.6.2 注册/注销任何在注册成功前或者注销成功后收到的事务都应该被 UE 拒绝。

6.6.2.1 初始注册注册流程如下图所示。


140

UE P-CSCF(pcscf1)


S-CSCF(scscf1)

HSS


1. REGISTER

2. DNS: DNS-Q

3. REGISTER

5. REGISTER

18.registrationnotification

19. 200 OK

20. 200 OK

21.200 OK


6.Authenticatio

n

8. 401Unauthorized

9. 401 Unauthorized

10. 401 Unauthorized

12. REGISTER

13. DNS: DNS-Q

14. REGISTER

16.REGISTER


7.Vector

Selection

11.of Response

andsession keys

17.Authentication

图53 注册流程

与 Gm 接口相关的消息包括步骤 2，11，12，13 和 22。

2．REGISTER 请求(UE to P-CSCF)

REGISTER sip:registrar.home1.net SIP/2.0 Via: SIP/2.0/UDP [5555::aaa:bbb:ccc:ddd];comp=sigcomp;branch=z9hG4bKnashds7 Max-Forwards: 70 P-Access-Network-Info: 3GPP-UTRAN-TDD; utran-cell-id-3gpp=234151D0FCE11


141

From: <sip:[email protected]>;tag=4fa3 To: <sip:[email protected]> Contact: <sip:[5555::aaa:bbb:ccc:ddd];comp=sigcomp>;expires=600000 Call-ID: apb03a0s09dkjdfglkj49111 Authorization: Digest username="[email protected]", realm="registrar.home1.net",

nonce="", uri="sip:registrar.home1.net", response="" Security-Client: ipsec-3gpp; alg=hmac-sha-1-96; spi-c=23456789; spi-s=12345678; port-c=2468;

port-s=1357 Require: sec-agree Proxy-Require: sec-agree CSeq: 1 REGISTER Supported: path Content-Length: 0

UE 发送 REGISTER 请求，需要在相关头域里面填写下列信息

a) Authorization 头域, 包含:

1) 用户指示，设置成用户的私有 ID；

2) 域名指示，设置成归属网络的域名；

3) uri 指示，设置成归属网络的 SIP URI 域名；

4) nonce 指示，设置成空；

5) 响应指示，设置成空；

b) From 头域，设置成将要注册的用户公共 ID 的 SIP URI;

c) To 头域，设置成将要注册的用户公共 ID 的 SIP URI;

d) Contact 头域，SIP URI，包含 UE 的 IP 地址或者 FQDN。如果 REGISTER 请求被 SA 保护，UE 的

保护端口也应该在 Contact 中体现；

e) Via 头域，设置成 UE 的 IP 地址或 FQDN；

f) Expires 头域，或者在 Contact 头中的 expires 参数，设置成 600 000 秒；

g) Request-URI，设成归属网络的 SIP URI 域名;

h) Security-Client 头域，表示了 UE 支持的安全机制，IPSec 算法，以及安全关联所需的参数；

i) Supported 头域，保护可选 tag “path”；

j) 如果安全关联存在，P-Access-Network-Info 头域表示 UE 接入网络的类型和相关信息。

11．401 Unauthorized response (P-CSCF to UE)

SIP/2.0 401 Unauthorized Via: SIP/2.0/UDP [5555::aaa:bbb:ccc:ddd];comp=sigcomp;branch=z9hG4bKnashds7 From: To: Call-ID: WWW-Authenticate: Digest realm="registrar.home1.net", nonce=base64(RAND + AUTN + server specific

data), algorithm=AKAv1-MD5 Security-Server: ipsec-3gpp; q=0.1; alg=hmac-sha-1-96; spi-c=98765432; spi-s=87654321;

port-c=8642; port-s=7531 CSeq: Content-Length:

WWW-Authenticate:包含了鉴权挑战。如果是 AKA 鉴权，P-CSCF 会把从 S-CSCF 收到的该字段中删

除 ik 和 ck 参数，再传给 UE。

Security-Server:q 是参考值，0.1 代表优选 IPSec。其值越低，优先级越高。

12. UE 回复并生成会话密钥

在收到未鉴权响应后，UE 能根据一定的算法算出会话密钥 ik 和 ck。

13. REGISTER request (UE to P-CSCF)

REGISTER sip:registrar.home1.net SIP/2.0


142

Via: SIP/2.0/UDP [5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 Max-Forwards: 70 P-Access-Network-Info: 3GPP-UTRAN-TDD; utran-cell-id-3gpp=234151D0FCE11 From: <sip:[email protected]>;tag=4fa3 To: <sip:[email protected]> Contact: <sip:[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp>;expires=600000 Call-ID: apb03a0s09dkjdfglkj49111 Authorization: Digest username="[email protected]", realm="registrar.home1.net",

nonce=base64(RAND + AUTN + server specific data), algorithm=AKAv1-MD5, uri="sip:registrar.home1.net", response="6629fae49393a05397450978507c4ef1"

Security-Client: ipsec-3gpp; alg=hmac-sha-1-96; spi-c=23456789; spi-s=12345678; port-c=2468; port-s=1357

Security-Verify: ipsec-3gpp; q=0.1; alg=hmac-sha-1-96; spi-c=98765432; spi-s=87654321; port-c=8642; port-s=7531

Require: sec-agree Proxy-Require: sec-agree CSeq: 2 REGISTER Supported: path Content-Length: 0

在收到 401 响应后，UE 需要发起另一个 REGISTER 请求，使用临时的安全关联来保护消息。头域里

面除了与初始请求相同的内容外，增加了 Authortization，Security-Client 和 Security-Verify 头域。

Authorization：包含从收到的 401 响应 WWW-Authenticate 头域中得到的域名，用户私有标识，以

及 UE 通过 RES 和其它参数计算出来的鉴权挑战响应；

Security-Client：与之前 REGISTER 请求的中的 Security-Client 相同；

Security-Verify：反应了接收到 401 响应中的 Security-Server 头域中的安全协定。

22. 200 OK response (P-CSCF to UE)

P-CSCF 保存 Service-Route 并与 UE 相关联。P-CSCF 前转 200OK 到 UE 表示注册成功。

在收到注册的 200 OK 后，UE 将使用新建立的安全关联与 P-CSCF 通信。

SIP/2.0 200 OK Via: SIP/2.0/UDP [5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 Path: Service-Route: <sip:[email protected];lr> From: To: Call-ID: Contact: CSeq: Date: P-Associated-URI: Content-Length:

Service-Route: 该头域是由 S-CSCF 来设置的，P-CSCF 只是转发给 UE。

6.6.2.2 重注册在初始注册完成后，UE 可以在任何时候进行重注册，但是必须用在与 contact 地址相关的那个安

全关联上进行重注册。重注册流程如下图所示。


143

UE P-CSCF(pcscf1)


S-CSCF(scscf1)

HSS


1. REGISTER

2. DNS: DNS-Q

3. REGISTER

5. REGISTER

7. 200 OK

8. 200 OK9. 200 OK


6. Update registration timer

图54 重注册流程

与 Gm 接口接口相关的消息涉及步骤 1 和 9，其中的步骤 1 消息 REGISTER 与 UE 未注册流程中的步

骤 11 的消息格式相同。

6.6.2.3 隐式注册如果是隐式注册，UE 将会在收到的 200OK（对应 REGISTER 请求）中得到多个 PUI，由

P-Associated-URI 标识。UE 需要根据 P-Associated-URI 头域中的信息保存已注册的 URI 列表。

有些 PUI 可能会被禁止，P-Associated-URI 头域中包含的只是未被禁止的 ID。

200 OK response (P-CSCF to UE)

SIP/2.0 200 OK Via: SIP/2.0/UDP [5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 Path: Service-Route: From: To: Call-ID: Contact: CSeq: Date: P-Associated-URI:<sip:[email protected]> P-Associated-URI:<tel:+1234567890> Content-Length:

UE 将使用 P-Associated-URI 的第一个 entry 作为默认的公共标识。

6.6.2.4 注册事件订阅在收到初始注册请求 2xx 响应后，UE 应通过 SUBSCRIBE 向 S-CSCF 订阅 registration state event

package。当注册状态发生变化时，S-CSCF 可以通过 NOTIFY 通知 UE。

UE 可以使用默认的 PUI 或者初始注册时使用的 PUI 进行订阅。

注册事件订阅流程如下图所示。


144

UE I-CSCF(icscf1_p)

S-CSCF(scscf1)


P-CSCF(pcscf1)

DNS

4. 202 (OK)

1. SUBSCRIBE

2. SUBSCRIBE

3. 200 (OK)

6. NOTIFY

5. NOTIFY

7. 200 (OK)

8. 200 (OK)

图55 注册事件订阅流程

与 Gm 接口相关的消息有步骤 1，4，6 和 7。

1.SUBSCRIBE request (UE to P-CSCF)

SUBSCRIBE sip:[email protected] SIP/2.0 Via: SIP/2.0/UDP [5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 Max-Forwards: 70 Route: <sip:pcscf1.visited1.net:7531;lr;comp=sigcomp>, <sip:[email protected];lr> P-Preferred-Identity: "John Doe" <sip:[email protected]> P-Access-Network-Info: 3GPP-UTRAN-TDD; utran-cell-id-3gpp=234151D0FCE11 Privacy: none From: <sip:[email protected]>;tag=31415 To: <sip:[email protected]> Call-ID: b89rjhnedlrfjflslj40a222 Require: sec-agree Proxy-Require: sec-agree CSeq: 61 SUBSCRIBE Event: reg Expires: 600000 Accept: application/reginfo+xml Security-Verify: ipsec-3gpp; q=0.1; alg=hmac-sha-1-96; spi-c=98765432; spi-s=87654321;

port-c=8642; port-s=7531 Contact: <sip:[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp> Content-Length: 0

在发送 SUBSCRIBE 请求时，UE 需要在相关头域里面填写下列信息

a) Request URI，设置成 UE 希望订阅的标识，如 SIP URI；

b) From 头域;

c) To 头域;

d) Event 头域，设成“reg”，表示用户订阅的是注册状态包;

e) Expires 头域，把订阅期限设成 600 000 秒；

f) P-Access-Network-Info 头域，指示接入网络信息；

g) Contact 头域，包含相同的 IP 地址或 FQDN，以及初始注册时使用的保护端口；

h) Accpet 头域，设置成 "application/reginfo+xml"。

4.200 (OK) response (P-CSCF to UE)

SIP/2.0 200 OK Via: SIP/2.0/UDP [5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7


145

Record-Route:<sip:pcscf1.home1.net:7531;lr;comp=sigcomp> P-Asserted-Identity: Privacy: From: To: Call-ID: CSeq: Expires: Contact: Content-Length:

NOTIFY request (P-CSCF to UE)

S-CSCF 发送 NOTIFY 给 UE，通知 UE 注册状态的变化，P-CSCF 转发该 NOTIFY 给 UE。 NOTIFY sip:[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp SIP/2.0 Via: SIP/2.0/UDP pcscf1.visited1.net:7531;comp=sigcomp;branch=z9hG4bK240f34.1, SIP/2.0/UDP

scscf1.home1.net;branch=z9hG4bK332b23.1 Max-Forwards: 69 From: To: Call-ID: CSeq: Subscription-State: active;expires=600000 Event: reg Content-Type: application/reginfo+xml Contact: <sip:scscf1.home1.net> Content-Length: (...) <?xml version="1.0"?> <reginfo xmlns="urn:ietf:params:xml:ns:reginfo" version="1" state="full"> <registration aor="sip:[email protected]" id="a7" state="active"> <contact id="76" state="active" event="registered"> <uri>sip:[5555::aaa:bbb:ccc:ddd]</uri> </contact> </registration> <registration aor="sip:[email protected]" id="a8" state="active"> <contact id="77" state="active" event="created"> <uri>sip:[5555::aaa:bbb:ccc:ddd]</uri> </contact> </registration> <registration aor="tel:+358504821437" id="a9" state="active"> <contact id="78" state="active" event="created"> <uri>sip:[5555::aaa:bbb:ccc:ddd]</uri> </contact> </registration> </reginfo>

NOTIFY 请求中的消息体包含了用户的注册状态，具体格式参见 3GPP TS24.229。

7.200 (OK) response (UE to P-CSCF)

SIP/2.0 200 OK Via: SIP/2.0/UDP pcscf1.visited1.net:7531;comp=sigcomp;branch=z9hG4bK240f34.1, SIP/2.0/UDP

scscf1.home1.net;branch=z9hG4bK332b23.1 P-Access-Network-Info: 3GPP-UTRAN-TDD; utran-cell-id-3gpp=234151D0FCE11 From: To: Call-ID: CSeq: Content-Length: 0

6.6.2.5 注销 a) UE发起的注销

在发起注销前，UE 应该释放与需要注销的 PUI 相关的所有会话。该过程与初始注册的过程相似，

在消息中的增加 Expires:0 或者 Contact 头域的 expires=0。这个 REGISTER 是经过鉴权的。


146

b) 网络发起的注销

当 UE 收到注册事件包的 NOTIFY，表示网络发起注销，<registration>中

1) 状态属性设成"terminated"，并且事件属性设成"rejected" 或 "deactivated"；

或者

2) 状态属性设成"active"并且在<contact>中的状态属性设成"terminated",相关的事件属性设成

"rejected" 或 "deactivated";

注销流程如下图所示：

UE I-CSCF(icscf1_p)

S-CSCF(scscf1)


P-CSCF(pcscf1)

DNS

1. SUBSCRIBE

2. NOTIFY

5. 200 (OK)

HSS

1. event occurs

3. NOTIFY

4. 200 (OK)

6. NOTIFY

7. 200 (OK)

8. S-CSCF deregistration notification

图56 注销流程

网络发起的注销是由 S-CSCF 发起 NOTIFY 通知 UE，与 Gm 接口相关的消息有步骤 3 和 4。

3. SIP NOTIFY request (P-CSCF to UE)

NOTIFY sip:[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp SIP/2.0 Via: SIP/2.0/UDP pcscf1.visited1.net:7531;comp=sigcomp;branch=z9hG4bK240f34.1, SIP/2.0/UDP

scscf1.home1.net;branch=z9hG4bK332b23.1 Max-Forwards: 69 Route: <sip:pcscf1.visited1.net;lr> From: <sip:[email protected]>;tag=151170 To: <sip:[email protected]>;tag=31415 Call-ID: b89rjhnedlrfjflslj40a222 CSeq: 43 NOTIFY Subscription-State: terminated Event: reg Content-Type: application/reginfo+xml Contact: sip:scscf1.home1.net Content-Length: (...) <?xml version="1.0"?> <reginfo xmlns="urn:ietf:params:xml:ns:reginfo" version="1" state="full"> <registration aor="sip:[email protected]" id="as9" state="terminated"> <contact id="76" state="terminated" event="deactivated"> <uri>sip:[5555::aaa:bbb:ccc:ddd]</uri> </contact> </registration> <registration aor="sip:[email protected]" id="as10" state="terminated"> <contact id="77" state="terminated" event="deactivated"> <uri>sip:[5555::aaa:bbb:ccc:ddd]</uri> </contact> </registration>


147

<registration aor="tel:+358504821437" id="as11" state="terminated"> <contact id="78" state="terminated" event="deactivated"> <uri>sip:[5555::aaa:bbb:ccc:ddd]</uri> </contact> </registration> </reginfo>

6.6.3 会话管理 6.6.3.1 MO

对于发起会话的 UE，UE 应在 Via 和 Contact 头域中加入保护的服务器端口，并插入

P-Access-Network-Info 头域。

UE 可以在任意的初始请求中插入 P-Preferred-Identity 头，内容可以包括下面其中之一：

1) 用户注册时使用的 PUI；

2) 在注册状态事件 package 返回的 NOTIFY 中表示隐式注册成功的 PUI；

MO-INVITE 流程如下图所示。

UE 需要支持 precondition 机制。如果 UE 不需要进行本地资源预留，那 UE 发起会话时也可以不带

precondition。

在成功预留资源后，UE 需要在接下来的 SIP 请求中进行确认。如果两端都使用 precondition 机制，

UE 用 PRACK 或者 UPDATE 请求进行确认；如果有一端不支持或者两端都不支持 precondition，那可以用

reINVITE 进行确认。

1. INVITE

27. 180 (Ringing)

3. INVITE

UE#1 P-CSCF S-CSCF


11. 183 (Session Progress)12. PRACK

16. 200 (OK)

25. 180 (Ringing)

28. PRACK

31. 200 (OK)

35. 200 (OK)

37. 200 (OK)

19. UPDATE

22. 200 (OK)

38. ACK

6. INVITE

26. 180 (Ringing)


34. 200 (OK)



2. 100 (Trying)

4. 100 (Trying)

7. 100 (Trying)

14. PRACK 15. PRACK

17. 200 (OK)18. 200 (OK)


23. 200 (OK)24. 200 (OK)

29. PRACK 30. PRACK

32. 200 (OK)33. 200 (OK)

39. ACK40. ACK


10. Authorize QoS resources


图57 MO-INVITE 流程


148

1．INVITE (UE to P-CSCF)

UE 发起 INVITE 请求，其消息格式

INVITE tel:+1-212-555-2222 SIP/2.0 Via: SIP/2.0/UDP [5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 Max-Forwards: 70 Route: <sip:pcscf1.visited1.net:7531;lr;comp=sigcomp>, <sip:scscf1.home1.net;lr> P-Preferred-Identity: "John Doe" <sip:[email protected]> P-Access-Network-Info: 3GPP-UTRAN-TDD; utran-cell-id-3gpp=234151D0FCE11 Privacy: none From: <sip:[email protected]>;tag=171828 To: <tel:+1-212-555-2222> Call-ID: cb03a0s09a2sdfglkj490333 Cseq: 127 INVITE Require: precondition, sec-agree Proxy-Require: sec-agree Supported: 100rel Security-Verify: ipsec-3gpp; q=0.1; alg=hmac-sha-1-96; spi-c=98765432; spi-s=87654321;

port-c=8642; port-s=7531 Contact: <sip:[5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp> Allow: INVITE, ACK, CANCEL, BYE, PRACK, UPDATE, REFER, MESSAGE Content-Type: application/sdp Content-Length: (…) v=0 o=- 2987933615 2987933615 IN IP6 5555::aaa:bbb:ccc:ddd s=- c=IN IP6 5555::aaa:bbb:ccc:ddd t=0 0 m=video 3400 RTP/AVP 98 99 b=AS:75 a=curr:qos local none a=curr:qos remote none a=des:qos mandatory local sendrecv a=des:qos none remote sendrecv a=rtpmap:98 H263 a=fmtp:98 profile-level-id=0 a=rtpmap:99 MP4V-ES m=audio 3456 RTP/AVP 97 96 b=AS:25.4 a=curr:qos local none a=curr:qos remote none a=des:qos mandatory local sendrecv a=des:qos none remote sendrecv a=rtpmap:97 AMR a=fmtp:97 mode-set=0,2,5,7; mode-change-period=2 a=rtpmap:96 telephone-event a=maxptime:20

Request-URI:包含了用户的 E.164 号码。

Via:包含了发起会话 UE 的 IP 地址或者 FQDN。

Route:包含了在 P-CSCF 发现过程中获得的 P-CSCF 地址，加上注册时得到的 Service-Route 里面的

信息。P-CSCF URI 中的端口号时在安全一致性协商中获取的。

Privacy:因为没有要求私密性，参考 RFC 3325 和 RFC 3323 设置成“none”。

P-Preferred-Identity:用户希望在此次对话中使用的标识。.

P-Access-Network-Info:UE 接入网络的类型和其它相关信息。

Security-Verify:包含了接收到的 Security-Server 头域中的安全协定。

Contact:发起会话 UE 的 SIP URI。.

SDP 包含了 UE 能支持并且希望在此次会话中使用的编码媒体参数。

2. 100 Trying (P-CSCF to UE)

P-CSCF 将给所有 INVITE 请求回 100（Trying）临时响应。


149

11. 183 Session Progress (P-CSCF to UE)

SIP/2.0 183 Session Progress Via: SIP/2.0/UDP [5555::aaa:bbb:ccc:ddd]:1357;comp=sigcomp;branch=z9hG4bKnashds7 Record-Route: <sip:pcscf2.visited2.net;lr>, <sip:scscf2.home2.net;lr>,

<sip:scscf1.home1.net;lr>, <sip:pcscf1.visited1.net:7531;lr;comp=sigcomp> P-Asserted-Identity: Privacy: From: To: Call-ID: CSeq: Require: Contact: Allow: RSeq: Content-Type: Content-Length: v= o= s= c= t= m= b= a= a= a= a= a= a= a= a= m= b= a= a= a= a= a= a= a= a= a=



6.6.3.2 MT 在会话被叫侧的 UE，当 UE 发送任意响应时，UE 应在 Contact 中增加被保护的 Server 端口，插入

P-Access-Network-Info 头域。

MT-INVITE 流程如下图所示。

如果被叫侧的 UE 需要从发起侧得到可靠的 alerting 指示，UE 应该发送 180 响应。


150

4. INVITE


S-CSCF P-CSCF

7. 100 (Trying)


12. PRACK

17. 200 (OK)

28. PRACK

31. 200 (OK)

34. 200 (OK)

36. 200 (OK)

19. UPDATE

UE#2

6. INVITE

38. ACK

1. INVITE


27. 180 (Ringing)

37. 200 (OK)



2. 100 (Trying)

5. 100 (Trying)


13. PRACK14. PRACK15. 200 (OK)

16. 200 (OK)

21. UPDATE22. 200 (OK)

24. 200 (OK)

29. PRACK30. PRACK

32. 200 (OK)33. 200 (OK)

39. ACK40. ACK

20. UPDATE

23. 200 (OK)




图58 MT-INVITE 流程

与 Gm 接口相关的消息有步骤 6，7，8，14，15，21，22，25，30，31，34 和 40。

6.6.3.3 匿名功能

当用户希望匿名时，RFC3323 推荐在 From 中匿名方式，如 From: “Anonymous” <sip: [email protected]>; tag=1234567890。但在 SIP From 中设置匿名并不能证实网络需要给

该用户提供私密性，UE 还需要在 SIP 消息中增加 Privacy 头部信息，值为”id”。这样在终结侧的 P-CSCF

就能在发送消息前删除 SIP 消息的 P-Asserted-Identity 和 Privacy 头。

6.6.4 安全 6.6.4.1 鉴权方法

Gm 接口应该支持 IMS AKA 鉴权、Early IMS 鉴权、HTTP Digest 鉴权、CAVE AKA 鉴权等鉴权方

式。

6.6.4.2 安全关联 Gm 接口需要建立安全关联 SA。

P-CSCF 支持通过 IMS AKA 建立 SA 的过程，能够与 UE 协商安全模式来建立 SA 参数，建立 SA 的过

程基于 RFC3329。

能够对于 TCP 和 UDP 进行不同的处理，

UDP 的情况：P-CSCF 在 port_ps（被保护的 server 端口）接收来自 UE 的通过 ESP 保护的请求或相

应消息。P-CSCF 在 port_pc(被保护的 client 端口)发送通过 ESP 保护的请求或响应消息到 UE。


151

TCP 的情况：如果还没有到 UE 的 TCP 连接，P-CSCF 在发送请求前先建立一个由它自己的 port_pc

端口到 UE 的 port_us 端口的 TCP 连接。

P-CSCF 仅允在被保护的端口接收登记消息和错误信息，其它没有到达被保护端口的消息都将被

P-CSCF 拒绝或丢弃。

6.6.4.3 完整性保护如果采用 IMS AKA 鉴权方式，Gm 接口中的 SIP 要求进行完整性保护。

可以采用IPSec ESP（RFC 2406 ）协议来提供UE和P-CSCF间SIP信令的完整性保护，保护IP层的所有

SIP信令。 6.6.5 信令压缩

为了节约链路带宽资源（特别是无线链路带宽资源），Gm 接口如果是无线接入就应该使用信令压缩

技术对 SIP 信令进行压缩处理，以便有效利用带宽，减少传输时延。

UE 支持 RFC3320 中定义的信令压缩，当使用信令压缩时，UE 按照 RFC 3486 压缩 SIP 消息，并将

被压缩的 SIP 请求或响应消息传递到 P-CSCF；另外 UE 将解压从 P-CSCF 收到的被压缩的请求或响应。 P-CSCF 支持 RFC3320[32]中定义的信令压缩，当使用信令压缩时，P-CSCF 按照 RFC3486 [55]压缩

发送到 UE 侧的 SIP 消息；另外 P-CSCF 将解压从 UE 侧收到的 SIP 请求和响应。

信令压缩可采用动态解压或者固定解压。


152

附录 A （规范性附录）

M 系列接口支持的消息

M 些列接口必须支持以下 SIP 消息，并符合相应的 IETF 规范中对各消息的定义。

ACK RFC3261

BYE RFC3261

CANCEL RFC3261

INVITE RFC3261

MESSAGE RFC3428

NOTIFY RFC3265

OPTIONS RFC3261

PRACK RFC3262

PUBLISH RFC3903

REFER RFC3515

REGISTER RFC3261

SUBSCRIBE RFC3265

UPDATE RFC3311

附录 B （规范性附录）

M 系列接口支持的消息头


153

B.1 基本的消息头

（1） To

在非注册消息中，To 消息头定义了消息的逻辑接收者，用户的 record 地址或资源。To 消息头中可

以包含 SIP URI 或者 tel URL。

在注册消息中，To 消息头定义了注册用户的 AOR 记录地址。

具体规定遵循 RFC 3261 中的定义。

（2） From

在非注册消息中，From 消息头定义了消息的逻辑发起者，有可能是用户的 record 地址。From 消息

头中可以包含 SIP URI 或者 tel URL 以及一个 display name。

在注册消息中，From 消息头定义了发起注册实体的 AOR 记录地址。


（3） Call-ID

Call-ID 消息头用于唯一标识一个对话（dialog）。在一个 dialog 中，任何 UA 发送的所有请求和

回应必须相同。


（4） Cseq

Cseq 消息头用于标识 transaction 和对 transaction 进行排序。它由一个序列号和一个方法组成，

方法必须与请求相匹配。


（5） Via

Via 消息头用于指示一个 transaction 的传输层信息，它是消息响应路由的依据。Via 消息头只有

在即将跳到下一跳时才会插入。

Via 消息头中必须包括一个 branch 参数，用于区分当前请求所建立的 transaction。


（6） Max-Forwards

Max-Forwards 消息头用于限制一个请求消息在到达目的地之前所经过的跳（hop）数。Max-Forwards

由一个整数构成，每经过一跳减 1。

UAC 必须向每个 request 插入 Max-Forwards 时，其值一般来说设为 70。


（7） Contact

Contact 消息头提供了 SIP URI，后续请求消息可以用它来联系该当前 UA，一般采用主机地址标识。

Contact 消息头必须存在于任何能够建立 Dialog 的请求中。


（8）其他

B.2 路由相关的消息头

（1） Via

Via 消息头用于对响应消息进行路由。

（2） Route

Route消息头用于对请求消息进行路由，它指定了请求消息必须经过它所设置的一系列的SIP Proxy

列表。

在初始请求中，Route 消息头可以由 UA 和 SIP Proxy 和插入。

在后续请求中，Route 消息头由 UA 插入，主叫 UA 将初始请求过程中获得的 Record-Route 消息头

中的所有条目顺序颠倒插入到 Route 消息头中，被叫 UA 将初始请求过程中获得的 Record-Route 消息头

中的所有条目插入到 Route 消息头中。


154


（3） Record-Route

Record-Route 消息头为后续请求记录 Route 消息头，它由 SIP Proxy 在初始请求中插入，保证了

后继消息仍然需要经过 Record-Route 所设置的一系列的 SIP Proxy 列表。


B.3 私有SIP消息头（P-header）

私有消息头（P-header）是指在有限环境中用于特殊目的（例如计费或路由）的 SIP 消息头。ISC

接口必须支持以下定义的几个 P-header。

（1） P-Asserted-Identity

P-Asserted-Identity 消息头用于传递信任域内主叫用户的标识，表明用户为通过鉴权的用户。当

消息发送给非信任域的 UE 或 SIP 实体时，并且用户申请了 privacy: id，则 P-Asserted-Identity 消

息头必须从消息中删掉。

具体规定遵循 RFC 3325 和 RFC 3323 中的定义。

（2） Privacy

Privacy 消息头用于让 UA 对某个 SIP 消息来设置一个特定的隐私级别，常见的隐私级别

有”id”,”user”,”session”等

具体规定遵循 RFC 3323 的定义。

（3） P-Charging-Vector

P-Charging-Vector 消息头用于在网络实体之间进行计费关联，它包括处理同一会话相关的各个网

元实体产生的 CDR 所需要的通用信息。

P-Charging-Vector 消息头包括 3 类计费关联信息：

a) IMS计费信息ICID（IMS Charging Identifier）：用于将CDR进行计费关联的唯一值。

b) 运营商标识IOI（Inter-Operator Identifiers）：可以由主叫或被叫方产生用于标识各自所在

的运营商网络。

c) 接入网计费信息：包括接入层特定的网络标识，用于将IP-CAN CDR与IM域的CDR进行关联，也就

是说将承载层与会话层相关联。

具体规定遵循 RFC 3455 和 3GPP 24.229 的定义。

（4） P-Charging-Function-Addresses

P-Charging-Function-Addresses 消息头用于给 SIP Proxy 提供一套公共的地址以供 SIP Proxy 传

送计费信息，它包含两个参数：CCF 和 ECF，其中 CCF 是 CDF 的地址，ECF 是 OCF 的地址。

在 IMS 中，P-Charging-Function-Addresses 可以由 S-CSCF 通过 Cx 接口获得，并由 S-CSCF 传递

到其他实体。另外，

P-Charging-Function-Addresses 也可以由 AS 通过 Sh 接口获得。

具体规定遵循 RFC 3455 和 3GPP 24.229 的定义。

中国联通ims接口规范 第一分册： mgw media gateway 媒体网关 mrfc multimedia resource...

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中国联通ims接口规范第一分册： mgw media gateway 媒体网关 mrfc multimedia resource...