Implementing Automatic Callback Using Session Initiation Protocol

Lisha Singh Lisha Singh
2013 IOSR Journal of Computer Engineering  
TheSession Initiation Protocol (SIP), is an application-layer control (signaling) protocol for creating, modifying, and terminating sessions with one or more participants. SIP is developed by SIP working group specified by the Internet Engineering Task Force (IETF), peer-to-peer communication protocol to establish, manipulate, and tear down communication sessions at application layer. These sessions include Internet telephone calls, multimedia distribution, and multimedia conferences. SIP
more » ... tions used to create sessions, carry session descriptions that allow participants to agree on a set of compatible media types. The Automatic Callback feature sends a priority ring on phone, indicating the previously busy or unanswered extension you dialed is now available. Callback feature allows to receive Callback notification when a called party line becomes available. Callback provides the ability of the system to suspend the call completion service if the user, who originated Callback, is currently busy and receives call-back notification when the called party becomes available. When the originating user then becomes available, the call completion service resumes for that user.
doi:10.9790/0661-1151220 fatcat:fk3eybrdung4tlpt47uxhqerta