Source note · SDP offer answer and codec negotiation

If the answerer has no media format in common for an offered stream it must reject that stream by setting the port to zero, and if there is no format in common for any stream the entire offered session is rejected.

Checked 2026-09-15

If the answerer has no media formats in common for a particular offered stream, the answerer MUST reject that media stream by setting the port to zero.

Vendor: IETF
Product: SIP
Subsystem: SDP offer/answer
Deployment: not restricted
Region: not restricted
Release range: RFC 3264
Checked: 2026-09-15

Sources

RFC 3264 — An Offer/Answer Model with the Session Description Protocol (SDP) — IETF / RFC Editor · tier 1 standards and regulators · RFC 3264 section 6.1 Unicast Streams

Cite this note

APA

WarmTransfer. (2026, September 15). SDP offer answer and codec negotiation: source note sdp-oa-no-common-format-is-a-port-zero-rejection. WarmTransfer. https://warmtransfer.net/knowledge/claims/sdp-oa-no-common-format-is-a-port-zero-rejection

BibTeX

@misc{warmtransfer-claim-sdp-oa-no-common-format-is-a-port-zero-rejection,
  title  = {SDP offer answer and codec negotiation: source note sdp-oa-no-common-format-is-a-port-zero-rejection},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/sdp-oa-no-common-format-is-a-port-zero-rejection},
  note   = {Source note sdp-oa-no-common-format-is-a-port-zero-rejection, checked 2026-09-15}
}

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