Source note · Troubleshooting SIP 403 Forbidden from a carrier
RFC 8224 defines 437 Unsupported Credential as sent when the verification service can acquire or already holds the credential named by the info parameter but does not support it.
Checked 2026-09-30
- Vendor
- IETF
- Product
- STIR
- Subsystem
- verification service
- Deployment
- any
- Region
- not restricted
- Release range
- current as of 2026-09-30
- Checked
- 2026-09-30
Sources
- RFC 8224: Authenticated Identity Management in the Session Initiation Protocol (SIP) — IETF / RFC Editor · tier 1 standards and regulators · section 6.2.2
Cite this note
APA
WarmTransfer. (2026, September 30). Troubleshooting SIP 403 Forbidden from a carrier: source note sip-403-forbidden-troubleshooting-rfc8224-437. WarmTransfer. https://warmtransfer.net/knowledge/claims/sip-403-forbidden-troubleshooting-rfc8224-437
BibTeX
@misc{warmtransfer-claim-sip-403-forbidden-troubleshooting-rfc8224-437,
title = {Troubleshooting SIP 403 Forbidden from a carrier: source note sip-403-forbidden-troubleshooting-rfc8224-437},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/claims/sip-403-forbidden-troubleshooting-rfc8224-437},
note = {Source note sip-403-forbidden-troubleshooting-rfc8224-437, checked 2026-09-30}
}