A new offer's origin line must be identical to the previous one except that the version increments by one, and if the version does not increment the SDP must be byte for byte the same, so a repeated version is a no operation that still requires a valid answer.

field report · Checked 2026-09-15

If the version in the origin line does not increment, the SDP MUST be identical to the SDP with that version number.
Vendor
IETF
Product
SIP
Subsystem
SDP offer/answer
Deployment
not restricted
Region
not restricted
Release range
RFC 3264
Status
field report
Checked
2026-09-15

Sources

Cite this note

APA

WarmTransfer. (2026, September 15). SDP offer answer and codec negotiation: source note sdp-oa-version-must-increment-or-be-identical. WarmTransfer. https://warmtransfer.net/knowledge/claims/sdp-oa-version-must-increment-or-be-identical

BibTeX

@misc{warmtransfer-claim-sdp-oa-version-must-increment-or-be-identical,
  title  = {SDP offer answer and codec negotiation: source note sdp-oa-version-must-increment-or-be-identical},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/sdp-oa-version-must-increment-or-be-identical},
  note   = {Source note sdp-oa-version-must-increment-or-be-identical, checked 2026-09-15}
}

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