Source note · SIP TLS handshake failures on trunks

Cisco says third-party systems that make TLS or mTLS connections to Dedicated Instance UC applications, such as SIP trunks to Unity Connection or Unified CM, must have IdenTrust Public Sector Root CA 1 in their trust store or those connections will fail.

Checked 2026-09-25

Vendor: Cisco
Product: Webex Calling Dedicated Instance
Subsystem: trust store
Deployment: dedicated-instance
Region: not restricted
Release range: certificate renewals from 2026-06-01
Checked: 2026-09-25

Sources

Public CA certificate changes impacting Dedicated Instance — Cisco · tier 2 current vendor documentation · Who is affected; Required actions

Cite this note

APA

WarmTransfer. (2026, September 25). SIP TLS handshake failures on trunks: source note sip-tls-handshake-failures-di-import-new-root. WarmTransfer. https://warmtransfer.net/knowledge/claims/sip-tls-handshake-failures-di-import-new-root

BibTeX

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

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