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SIP扩展与相关RFC介绍
Version 1.0
2008-9-15
来源:http://blog.csdn.net/netnote/archive/2008/11/26/3379004.aspxSIP扩展可分成几个类型:
增加了消息SUBSCRIBE、NOTIFY,
SUBSCRIBE发起订阅,订阅拥有状态(激活、等待、
事件包,一种扩展机制;事件模板包,一种特殊的事件包;
PUBLISH方法,
Event head;
两种消息交互方式:页面模式与session模式;
页面模式:每个消息是独立的,
Session模式:使用SIP建立session,
与传统电信网络中呼叫建立前信令对应的SIP临时消息,
仅适用于INVITE的临时响应;
本扩展的标识100rel;
RSeq头,类似CSeq;PRACK的RACK头,
不能对100 Trying使用可靠传输机制,
用于不影响当前dialog情况下更新会话描述,
早期阶段(early INVITE-initiated):client获得1xx(
确定阶段:得到2XX应答后;
UPDATE仅用于dialog;
UPDATE携带SDP offer,其2xx应答携带answer;
用于session建立前的资源预留,
Caller在初始SDP中指明本次会话的约束,
SDP中的约束信息如:a=des:qos sptimal e2e send
发送者指引接收者去访问REFER请求中所标识的资源;
REFER与NOTIFY综合使用,实现呼叫转移功能;
呼转的类型:
可能的过程:
成功的呼转并不改变Transferor与Transfe
Path扩展可用于记录REGISTER从UA到regi
如果UA支持path扩展,
用于可信网络中判断终端用户、系统的身份;
RFC3320,信令压缩规范,
URI参数 comp=SigComp
使用request URI与via、route头,指示节点的压缩支持;
提供一种在sip session执行建立操作开始后,
在SIP消息体中包装ISUP消息;使用INFO(RFC 2976)消息传输呼叫中的信令;
MIME类型message/sipfrag;
安全协商,
P-Media-Authorization
UA可以在发出的请求中包含一系列Route头,
Service-Route头,用于UA学习服务路由;
专用于3GPP IMS;
P-Charging-Vector,IMS计费ID(
P-Charging-Function-
P-Visited-Network-ID,
P-Access-Network-Info,
P-Called-Party-ID,
P-Associated-URI,
Session Initiation Protocol (SIP) Basic Call Flow Examples
3rd party call control in sip
新的SDP标准是RFC4566(2006.7),
Early Media and Ringing Tone Generation in the Session Initiation
Session Initiation Protocol (SIP): Locating SIP Servers
URLS for telephone calls
Conventions for the use of the Session Description Protocol (SDP) for ATM Bearer Connections
MIME media types for ISUP and QSIG Objects
A Privacy Mechanism for SIP
The Reason Header Field
RFC 3261: SIP Session initiation protocol.
RFC 3263: Session Initiation Protocol (SIP): Locating SIP Servers.
RFC 2327: SDP Session Description Protocol.
RFC 3420: Internet Media Type message/ipfrag.
RFC 2976: The SIP INFO Method
RFC 2806: URLS for telephone calls
RFC 3108: Conventions for the use of the Session Description Protocol (SDP) for ATM Bearer Connections
RFC 3204: MIME media types for ISUP and QSIG Objects
RFC 3262: Reliability of Provisional Responses in SIP
RFC 3264: An Offer/Answer Model with the Session Description Protocol (SDP)
RFC 3265: SIP-Specific Event Notification
RFC 3310: HTTP Digest Authentication Using AKA
RFC 3311: The SIP UPDATE method
RFC 3313: Media Authorization
RFC 3323: A Privacy Mechanism for SIP
RFC 3325: Asserted Identity within Trusted Networks
RFC 3326: The Reason Header Field
RFC 3327: Extension Header Field for Registering Non-Adjacent Contacts (Path)
RFC 3372 : SIP for Telephones (SIP-T): Context and Architectures
RFC 3428: The SIP MESSAGE method
RFC 3455: Private Header Extensions to SIP for 3GPP
RFC 3515: The SIP REFER method
RFC 3581: An Extension to SIP for Symmetric Response Routing.
RFC 3608: SIP Extension Header Field for Service Route Discovery During Registration
RFC 3842: A Message Summary and Message Waiting Indication Event Package for SIP
RFC 3856: SIP Extensions for Presence
RFC 3891: The SIP "Replaces" Header
RFC 3892: The SIP Referred-By Mechanism
RFC 3959: early session disposition type for SDP
RFC 4028: Session Timers in SIP
ITU-T T.38 Annex D (04/2004) and RFC 3362 for support of T.38 in SIP
IETF draft-levy-sip-diversion-08.
draft-ietf-sipping-kpml-07.
参考文献
[1] Miikka Poikselka等,The IMS IP Multimedia Concepts and Services,机械工业,2007.7;
[2] Dialogic,Dialogic Global Call IP,2008.3;