Source note · SDP offer answer and codec negotiation
An fmtp parameter that describes a specific configuration of a media format must appear in the answer with the same value if that format is kept, while an fmtp parameter that is merely a parameter may differ between the two agents.
Checked 2026-09-15
This means that the same fmtp parameters with the same values MUST be present in the answer if the media format they describe is present in the answer.
- 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-configuration-fmtp-must-be-echoed. WarmTransfer. https://warmtransfer.net/knowledge/claims/sdp-oa-configuration-fmtp-must-be-echoed
BibTeX
@misc{warmtransfer-claim-sdp-oa-configuration-fmtp-must-be-echoed,
title = {SDP offer answer and codec negotiation: source note sdp-oa-configuration-fmtp-must-be-echoed},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/claims/sdp-oa-configuration-fmtp-must-be-echoed},
note = {Source note sdp-oa-configuration-fmtp-must-be-echoed, checked 2026-09-15}
}