For Microsoft 365, Office 365 and GCC, the SBC connects over SIP/TLS to destination port 5061 on sip.pstnhub.microsoft.com, sip2.pstnhub.microsoft.com and sip3.pstnhub.microsoft.com, in that priority order.

Checked 2026-09-25

Vendor
Microsoft
Product
Teams Phone Direct Routing
Subsystem
SIP signaling
Deployment
multi-tenant
Region
global (commercial and gcc; gcc high and dod use different fqdns)
Release range
current as of 2026-09-25
Checked
2026-09-25

Sources

Cite this note

APA

WarmTransfer. (2026, September 25). Unified CM and Teams Phone coexistence during a migration: source note cucm-teams-coexistence-dr-sip-signaling. WarmTransfer. https://warmtransfer.net/knowledge/claims/cucm-teams-coexistence-dr-sip-signaling

BibTeX

@misc{warmtransfer-claim-cucm-teams-coexistence-dr-sip-signaling,
  title  = {Unified CM and Teams Phone coexistence during a migration: source note cucm-teams-coexistence-dr-sip-signaling},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/cucm-teams-coexistence-dr-sip-signaling},
  note   = {Source note cucm-teams-coexistence-dr-sip-signaling, checked 2026-09-25}
}

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