Microsoft Teams SIP interface client and server certificates chain to one of seven roots (DigiCert Global Root CA, DigiCert Global Root G2, DigiCert Global Root G3, DigiCert TLS ECC P384 Root G5, DigiCert TLS RSA 4096 Root G5, Microsoft ECC Root CA 2017 and Microsoft RSA Root CA 2017), and SBCs must trust all of them.

Checked 2026-09-25

Vendor
Microsoft
Product
Teams Phone Direct Routing
Subsystem
trust store
Deployment
multi-tenant
Region
not restricted
Release range
from entry dated 2025-12-12; in production since end of July 2026
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-supported-roots-2025. WarmTransfer. https://warmtransfer.net/knowledge/claims/sip-tls-handshake-failures-dr-supported-roots-2025

BibTeX

@misc{warmtransfer-claim-sip-tls-handshake-failures-dr-supported-roots-2025,
  title  = {SIP TLS handshake failures on trunks: source note sip-tls-handshake-failures-dr-supported-roots-2025},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/sip-tls-handshake-failures-dr-supported-roots-2025},
  note   = {Source note sip-tls-handshake-failures-dr-supported-roots-2025, checked 2026-09-25}
}

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