Source note · Early media and ringback behavior

RFC 5009 defines the P-Early-Media header so that SIP networks can authorize cut-through of backward and/or forward early media when their early media policies allow it.

Checked 2026-09-24

Vendor: IETF
Product: SIP
Subsystem: early media authorization
Deployment: any
Region: not restricted
Release range: RFC 5009
Checked: 2026-09-24

Sources

RFC 5009: Private Header (P-Header) Extension to the Session Initiation Protocol (SIP) for Authorization of Early Media — IETF / RFC Editor · tier 1 standards and regulators · Section 1 (Introduction)

Cite this note

APA

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

BibTeX

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

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