Source note · SIP call forwarding and routing loops

Microsoft's Direct Routing SIP guidance says the History-Info header should be used for loop prevention in call-forwarding scenarios.

Checked 2026-09-25

The History-Info header should be used for loop-prevention.

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

Sources

Teams Phone System Direct Routing: SIP protocol — Microsoft · tier 2 current vendor documentation · Call forwarding section, final bullet

Cite this note

APA

WarmTransfer. (2026, September 25). SIP call forwarding and routing loops: source note sip-forwarding-loops-teams-dr-hi-loop-prevention. WarmTransfer. https://warmtransfer.net/knowledge/claims/sip-forwarding-loops-teams-dr-hi-loop-prevention

BibTeX

@misc{warmtransfer-claim-sip-forwarding-loops-teams-dr-hi-loop-prevention,
  title  = {SIP call forwarding and routing loops: source note sip-forwarding-loops-teams-dr-hi-loop-prevention},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/sip-forwarding-loops-teams-dr-hi-loop-prevention},
  note   = {Source note sip-forwarding-loops-teams-dr-hi-loop-prevention, checked 2026-09-25}
}

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