Microsoft states that TLS between its SIP endpoints and customer or partner SBCs for Direct Routing and Operator Connect is mutual TLS, with the Microsoft side presenting a client certificate.

Checked 2026-09-25

Vendor
Microsoft
Product
Teams Phone Direct Routing
Subsystem
mutual TLS
Deployment
multi-tenant
Region
not restricted
Release range
as stated in entry dated 2025-12-12
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-mtls-both-directions. WarmTransfer. https://warmtransfer.net/knowledge/claims/sip-tls-handshake-failures-dr-mtls-both-directions

BibTeX

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

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