The Session Initiation Protocol: Providing advanced telephony services across the Internet
- 14 August 2002
- journal article
- Published by Institute of Electrical and Electronics Engineers (IEEE) in Bell Labs Technical Journal
- Vol. 3 (4) , 144-160
- https://doi.org/10.1002/bltj.2133
Abstract
During the past few years, Internet telephony has evolved from a toy for the technically savvy to a technology that, in the not too distant future, may replace the existing circuit-switched telephone network. Supporting the widespread use of Internet telephony requires a host of standardized protocols to ensure quality of service (QoS), transport audio and video data, provide directory services, and enable signaling. Signaling protocols are of particular interest because they are the basis for advanced services such as mobility, universal numbers, multiparty conferencing, voice mail, and automatic call distribution. Two signaling protocols have emerged to fill this need: the ITU-T H.323 suite of protocols and session initiation protocol (SIP), developed by the Internet Engineering Task Force (IETF). In this paper we examine how SIP is used in Internet telephony. We present an overview of the protocol and its architecture, and describe how it can be used to provide a number of advanced services. Our discussion of some of SIP's strengths - its simplicity, scalability, extensibility, and modularity - also analyzes why these are critical components for an IP telephony signaling protocol. SIP will prove to be a valuable tool, not just for end-to-end IP services, but also for controlling existing phone services.Keywords
This publication has 22 references indexed in Scilit:
- Internet telephony gateway locationPublished by Institute of Electrical and Electronics Engineers (IEEE) ,2002
- Signaling for Internet telephonyPublished by Institute of Electrical and Electronics Engineers (IEEE) ,2002
- YESSIRACM SIGCOMM Computer Communication Review, 1999
- The mailto URL schemePublished by RFC Editor ,1998
- Real Time Streaming Protocol (RTSP)Published by RFC Editor ,1998
- SDP: Session Description ProtocolPublished by RFC Editor ,1998
- Network performance effects of HTTP/1.1, CSS1, and PNGACM SIGCOMM Computer Communication Review, 1997
- Resource ReSerVation Protocol (RSVP) -- Version 1 Message Processing RulesPublished by RFC Editor ,1997
- MIME (Multipurpose Internet Mail Extensions): Mechanisms for Specifying and Describing the Format of Internet Message BodiesPublished by RFC Editor ,1992
- Domain names - concepts and facilitiesPublished by RFC Editor ,1987