Source note · Setting up an Oracle SBC for Teams Direct Routing

Every OPTIONS and INVITE sent to the Microsoft SIP proxy must carry the paired SBC FQDN as the Contact URI host with transport=tls; a Contact whose host is an IP address is refused with 403 Forbidden.

Checked 2026-09-30

Vendor: Microsoft
Product: Microsoft Teams Phone Direct Routing
Subsystem: SIP headers
Deployment: multi-tenant
Region: not restricted
Release range: current as of 2026-09-30
Checked: 2026-09-30

Sources

Teams Phone System Direct Routing: SIP protocol — Microsoft · tier 2 current vendor documentation · Detailed requirements for Contact header and Request-URI, Contact header

Cite this note

APA

WarmTransfer. (2026, September 30). Setting up an Oracle SBC for Teams Direct Routing: source note oracle-sbc-teams-direct-routing-setup-contact-fqdn. WarmTransfer. https://warmtransfer.net/knowledge/claims/oracle-sbc-teams-direct-routing-setup-contact-fqdn

BibTeX

@misc{warmtransfer-claim-oracle-sbc-teams-direct-routing-setup-contact-fqdn,
  title  = {Setting up an Oracle SBC for Teams Direct Routing: source note oracle-sbc-teams-direct-routing-setup-contact-fqdn},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/oracle-sbc-teams-direct-routing-setup-contact-fqdn},
  note   = {Source note oracle-sbc-teams-direct-routing-setup-contact-fqdn, checked 2026-09-30}
}

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