Source note · Early media and ringback behavior

RFC 3959 requires early-session bodies to follow the offer/answer model and allows them in the same messages as session bodies, with specified exceptions.

Checked 2026-09-24

Vendor: IETF
Product: SIP
Subsystem: early media
Deployment: any
Region: not restricted
Release range: RFC 3959
Checked: 2026-09-24

Sources

RFC 3959: The Early Session Disposition Type for the Session Initiation Protocol (SIP) — IETF / RFC Editor · tier 1 standards and regulators · Section 4

Cite this note

APA

WarmTransfer. (2026, September 24). Early media and ringback behavior: source note early-media-ringback-early-session-offer-answer. WarmTransfer. https://warmtransfer.net/knowledge/claims/early-media-ringback-early-session-offer-answer

BibTeX

@misc{warmtransfer-claim-early-media-ringback-early-session-offer-answer,
  title  = {Early media and ringback behavior: source note early-media-ringback-early-session-offer-answer},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/early-media-ringback-early-session-offer-answer},
  note   = {Source note early-media-ringback-early-session-offer-answer, checked 2026-09-24}
}

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