RFC 3261 defines 415 Unsupported Media Type as the server refusing a request because the message body is in a format the server does not support for that method; it concerns the body type (for example the Content-Type) rather than codecs inside SDP.

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-rfc3261-415-meaning. WarmTransfer. https://warmtransfer.net/knowledge/claims/sip-488-codec-failures-rfc3261-415-meaning

BibTeX

@misc{warmtransfer-claim-sip-488-codec-failures-rfc3261-415-meaning,
  title  = {SIP 488 and codec negotiation failures: source note sip-488-codec-failures-rfc3261-415-meaning},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/sip-488-codec-failures-rfc3261-415-meaning},
  note   = {Source note sip-488-codec-failures-rfc3261-415-meaning, checked 2026-09-25}
}

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