In Direct Routing, SBCs inside one voice route are tried in random order, and if none in the higher-priority route is available, the next lower-priority route matching the same pattern is tried; if no SBC is available the call is dropped.

Checked 2026-09-25

Vendor
Microsoft
Product
Teams Phone Direct Routing
Subsystem
call routing
Deployment
multi-tenant
Region
not restricted
Release range
current as of 2026-09-25
Checked
2026-09-25

Sources

Cite this note

APA

WarmTransfer. (2026, September 25). SIP trunk redundancy and failover design: source note sip-trunk-redundancy-design-ms-route-priority-backup. WarmTransfer. https://warmtransfer.net/knowledge/claims/sip-trunk-redundancy-design-ms-route-priority-backup

BibTeX

@misc{warmtransfer-claim-sip-trunk-redundancy-design-ms-route-priority-backup,
  title  = {SIP trunk redundancy and failover design: source note sip-trunk-redundancy-design-ms-route-priority-backup},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/sip-trunk-redundancy-design-ms-route-priority-backup},
  note   = {Source note sip-trunk-redundancy-design-ms-route-priority-backup, checked 2026-09-25}
}

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