Microsoft says inbound History-Info is preserved when ForwardCallHistory is enabled and that History-Info should be used for loop prevention on forwarded calls.
Checked 2026-10-02
- Vendor
- Microsoft
- Product
- Teams Phone Direct Routing
- Subsystem
- SIP proxy
- Deployment
- multi-tenant
- Region
- not restricted
- Release range
- current as of 2026-10-02
- Checked
- 2026-10-02
Sources
- Teams Phone System Direct Routing: SIP protocol — Microsoft · tier 2 current vendor documentation · Call forwarding; History-Info header
Cite this note
APA
WarmTransfer. (2026, October 2). SIP identity headers: P-Asserted-Identity and Diversion and History-Info: source note sip-identity-headers-teams-hi-loop-prevention. WarmTransfer. https://warmtransfer.net/knowledge/claims/sip-identity-headers-teams-hi-loop-prevention
BibTeX
@misc{warmtransfer-claim-sip-identity-headers-teams-hi-loop-prevention,
title = {SIP identity headers: P-Asserted-Identity and Diversion and History-Info: source note sip-identity-headers-teams-hi-loop-prevention},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/claims/sip-identity-headers-teams-hi-loop-prevention},
note = {Source note sip-identity-headers-teams-hi-loop-prevention, checked 2026-10-02}
}