Under RFC 5630 a SIPS URI requires TLS on every hop through to the remote UAS, deprecating RFC 3261's last-hop exception, while a SIP URI sent over TLS is only best-effort protection.

Checked 2026-09-25

Vendor

IETF

Product

SIP

Subsystem

SIPS

Deployment

any

Region

not restricted

Release range

RFC 5630 (October 2009)

Checked

2026-09-25

Sources

• RFC 5630: The Use of the SIPS URI Scheme in the Session Initiation Protocol (SIP) — IETF · tier 1 standards and regulators · Overview of SIPS semantics and last-hop exception text (section numbers not captured)

Cite this note

APA

WarmTransfer. (2026, September 25). SIP TLS handshake failures on trunks: source note sip-tls-handshake-failures-rfc5630-sips-every-hop. WarmTransfer. https://warmtransfer.net/knowledge/claims/sip-tls-handshake-failures-rfc5630-sips-every-hop

BibTeX

@misc{warmtransfer-claim-sip-tls-handshake-failures-rfc5630-sips-every-hop,
  title  = {SIP TLS handshake failures on trunks: source note sip-tls-handshake-failures-rfc5630-sips-every-hop},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/sip-tls-handshake-failures-rfc5630-sips-every-hop},
  note   = {Source note sip-tls-handshake-failures-rfc5630-sips-every-hop, checked 2026-09-25}
}

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