Under RFC 5922 an implementation may examine the certificate CN field only if the certificate has no subjectAltName.

Checked 2026-09-24

If and only if the subjectAltName does not appear in the certificate, the implementation MAY examine the CN field of the certificate.
Vendor
IETF
Product
SIP over TLS
Subsystem
TLS identity
Deployment
any
Region
not restricted
Release range
RFC 5922 (June 2010)
Checked
2026-09-24

Sources

Cite this note

APA

WarmTransfer. (2026, September 24). DNS SRV and service discovery for SIP: source note dns-srv-voice-rfc5922-cn-fallback. WarmTransfer. https://warmtransfer.net/knowledge/claims/dns-srv-voice-rfc5922-cn-fallback

BibTeX

@misc{warmtransfer-claim-dns-srv-voice-rfc5922-cn-fallback,
  title  = {DNS SRV and service discovery for SIP: source note dns-srv-voice-rfc5922-cn-fallback},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/dns-srv-voice-rfc5922-cn-fallback},
  note   = {Source note dns-srv-voice-rfc5922-cn-fallback, checked 2026-09-24}
}

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