Basic INVITE

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Opened 2026-10. A row marked confirm has no link, because that page was not verified.

RFC. RFC 3261, SIP last checked 2026-10
RFC. RFC 3550, RTP last checked 2026-10
RFC. RFC 4566, SDP last checked 2026-10
Cisco. Cisco Unified Communications Manager product support last checked 2026-10
Cisco. System Configuration Guide for CUCM, Release 15 last checked 2026-10
Protocol and ports. CUCM 15 TCP and UDP port usage last checked 2026-10
Protocol and ports. IANA SIP parameters last checked 2026-10
Protocol and ports. IANA RTP parameters last checked 2026-10
Community. Cisco Community, Collaboration knowledge base last checked 2026-10
Wikipedia. Session Initiation Protocol (Wikipedia) last checked 2026-10
Wikipedia. Real-time Transport Protocol (Wikipedia) last checked 2026-10
Cisco. Collaboration 12 SRND book. confirm. The historical Collaboration 12 SRND path opened as a product listing, not the design book. Use the Preferred Architecture index, which was opened. last checked 2026-10
RFC. RFC 3264, offer/answer last checked 2026-10
RFC. RFC 3515, SIP REFER last checked 2026-10
Cisco. Cisco Unified Border Element product support last checked 2026-10
Cisco. Understand IOS and IOS XE call routing last checked 2026-10