Session Initiation Protocol
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... multimedia
session data such as voice, video, or text messages. The Session
Initiation Protocol (SIP) works in concert with these protocols by
...
... Handley, M., Schulzrinne, H., Schooler, E. and J. Rosenberg, "SIP: Session Initiation Protocol", RFC 2543(-> 3265prop | 3264prop | 3263prop | 3262prop | 3261prop), March 1999. ...