SIP user agents should also indicate which methods and features they sup-
port using the Allow, Supported, Allow-Events, and Accept-Content
header fields.Summary
The basic operation and functions of the SIP protocol have been covered in this
overview chapter. The following chapters will use these basic functions of SIP
to build networks and implement services and features.References
[1] “Guidelines for Authors of Extensions to SIP” by J. Rosenberg. Internet
Draft, IETF, November 2002.
[2] “Hypertext Transfer Protocol — HTTP/1.1” R. Fielding, et al. IETF RFC
2616, 1999.
[3] “Simple Mail Transfer Protocol” by J. Postel. IETF RFC 821, 1982.
[4] “Session Timers in SIP” by S. Donovan and J. Rosenberg. Internet Draft,
IETF, February 2004.
[5] “The Internet Multimedia Conferencing Architecture” by M. Handley, J.
Crowcroft, C. Borman, and J. Ott. IETF Internet-Draft, Work in Progress,
July 2000.
[6] “SIP: Session Initiation Protocol” by J. Rosenberg, H. Schulzrinne, G.
Camarillo, A. Johnston, J. Peterson, R. Sparks, M. Handley, and E. Schooler.
RFC 3261, June 2002.
[7] SIP: Understanding the Session Initiation Protocolby A. Johnston, 2nd Edition,
Artech House: Boston, 2004.
[8] “RFC 1121: Requirements for Internet Hosts — Communication Layers” by
R. Braden, IETF, 1989.
[9] “A DNS RR for specifying the location of services (DNS SRV)” by A. Gul-
brandsen. IETF RFC 2782, 2000.
[10] “E.164 number and DNS,” P. Faltstrom. IETF RFC 2916, 2000.
[11] “SCTP as a Transport for SIP” by J. Rosenberg and H. Schulzrinne. IETF
Internet-Draft, Work in Progress, November 2004.
[12] “SDP: Session Description Protocol” by M. Handley and V. Jacobson. IETF
RFC 2327, 1998.
[13] “Requirements for Session Description and Capability Negotiation” by D.
Kutscher, et al. IETF Internet Draft, Work in Progress.
[14] “The SIPINFOMethod” by S. Donovan. IETF RFC 2976, 2000.
[15] “The Session Initiation Protocol (SIP) Refer Method” by R. Sparks. RFC
3515, April 2003.132 Chapter 6