RFC 3261 defines 488 Not Acceptable Here in section 21.4.26 as a 4xx rejection of the session description offered in the request, scoped to the addressed resource, with 606 Not Acceptable in section 21.6.4 as its global-failure counterpart.

Checked 2026-09-25

Vendor
IETF
Product
SIP
Subsystem
response codes
Deployment
any
Region
not restricted
Release range
RFC 3261
Checked
2026-09-25

Sources

Cite this note

APA

WarmTransfer. (2026, September 25). SIP 488 and codec negotiation failures: source note sip-488-codec-failures-rfc3261-488-defined. WarmTransfer. https://warmtransfer.net/knowledge/claims/sip-488-codec-failures-rfc3261-488-defined

BibTeX

@misc{warmtransfer-claim-sip-488-codec-failures-rfc3261-488-defined,
  title  = {SIP 488 and codec negotiation failures: source note sip-488-codec-failures-rfc3261-488-defined},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/sip-488-codec-failures-rfc3261-488-defined},
  note   = {Source note sip-488-codec-failures-rfc3261-488-defined, checked 2026-09-25}
}

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