Session Initiation Protocol
SIP is a agreement developed by the Internet Engineering Task Force (IETF) Multiparty
Multimedia Session Ascendancy (MMUSIC) Working Group as an another to H.323. SIP
features are adjustable with IETF RFC 2543, appear in March 1999; RFC 3261, published
in June 2002; and RFC 3665, appear in December 2003. Because SIP is a common
standard based on the argumentation of the World Wide Web and is actual simple to implement,
it is broadly acclimated with gateways and proxy servers aural account provider networks
for centralized and end-customer signaling.
SIP is a peer-to-peer agreement area user agents (UAs) admit sessions, agnate to H.323.
However, clashing H.323, SIP uses ASCII-text-based letters to communicate. Therefore,
you can apparatus and troubleshoot SIP actual easily.
Because SIP is a peer-to-peer protocol, the Cisco UCM does not ascendancy SIP devices, and
SIP accessories do not annals with Cisco UCM. As with H.323 gateways, alone the IP
address is accessible on Cisco UCM to affirm that advice amid a Cisco
UCM and a SIP articulation aperture is possible.