台湾宜兰大学 VOIP Course-02.pdf

Session Initiation Protocol (SIP) 陳懷恩博士 助理教授兼計算機中心資訊網路組組長 國立宜蘭大學資工系 Email: wechen@.tw TEL: 03-9357400 # 340 Outline Session Initiation Protocol SIP Extensions SIP Operation Examples References QA 2 Session Initiation Protocol Introduction [1/2] SIP: Session Initiation Protocol Originally developed in the MMUSIC working group of the IETF Great interest led to a separate SIP working Group RFC 2543RFC 3261 SIP is used in conjunction with several other IETF protocols, such as SDP and RTP. SIP has been selected as the interfaces between the IP Multimedia Core Network elements. ※ RFC: Request for Comments MMUSIC: Multiparty Multimedia Session Control SDP: Session Description Protocol IETF: Internet Engineering Task Force RTP: Real-time Transport Protocol 4 Introduction [2/2] SIP is a powerful alternative to H.323. More flexible Simpler Easier to implement Better suited to the support of intelligent user devices Better suited to the implementation of advanced features SIP+MGCP/MEGACO will be the dominant VoIP signaling architecture of the future. ※MGCP/MEGACO: Media Gateway Control Protocol VoIP: Voice over IP 5 Architecture SIP is a signaling protocol. Setup a session Find user’s current location Use SDP to carry session information Modify a session Teardown a session SIP signaling is separate fr