Source note · SIP trunk redundancy and failover design
When two or more SBCs in one Direct Routing voice route are healthy and equal, Microsoft distributes calls between them with a Fisher-Yates shuffle.
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
- Monitor Direct Routing — Microsoft · tier 2 current vendor documentation · Monitoring availability of Session Border Controllers using SIP options messages, final paragraph
Cite this note
APA
WarmTransfer. (2026, September 25). SIP trunk redundancy and failover design: source note sip-trunk-redundancy-design-ms-fisher-yates. WarmTransfer. https://warmtransfer.net/knowledge/claims/sip-trunk-redundancy-design-ms-fisher-yates
BibTeX
@misc{warmtransfer-claim-sip-trunk-redundancy-design-ms-fisher-yates,
title = {SIP trunk redundancy and failover design: source note sip-trunk-redundancy-design-ms-fisher-yates},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/claims/sip-trunk-redundancy-design-ms-fisher-yates},
note = {Source note sip-trunk-redundancy-design-ms-fisher-yates, checked 2026-09-25}
}