Microsoft SIP endpoints currently accept SBC certificates that lack the Client Authentication EKU, and Microsoft expects this to continue for the foreseeable future with advance notice of any change.

Checked 2026-09-25

Vendor
Microsoft
Product
Teams Phone Direct Routing
Subsystem
SBC certificate
Deployment
multi-tenant
Region
not restricted
Release range
current as of 2026-09-25
Checked
2026-09-25

Sources

Cite this note

APA

WarmTransfer. (2026, September 25). SIP TLS handshake failures on trunks: source note sip-tls-handshake-failures-dr-client-eku-not-required. WarmTransfer. https://warmtransfer.net/knowledge/claims/sip-tls-handshake-failures-dr-client-eku-not-required

BibTeX

@misc{warmtransfer-claim-sip-tls-handshake-failures-dr-client-eku-not-required,
  title  = {SIP TLS handshake failures on trunks: source note sip-tls-handshake-failures-dr-client-eku-not-required},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/sip-tls-handshake-failures-dr-client-eku-not-required},
  note   = {Source note sip-tls-handshake-failures-dr-client-eku-not-required, checked 2026-09-25}
}

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