Source note · Troubleshooting SIP 403 Forbidden from a carrier
On Teams Direct Routing outbound calls the caller ID is carried in the From and P-Asserted-Identity headers, and the P-Asserted-Identity header contains the phone number of the user who is billed for the call.
Checked 2026-09-30
- Vendor
- Microsoft
- Product
- Teams Phone Direct Routing
- Subsystem
- caller ID
- Deployment
- multi-tenant
- Region
- not restricted
- Release range
- current as of 2026-09-30
- Checked
- 2026-09-30
Sources
- Issues with outbound calls - Microsoft Teams — Microsoft · tier 2 current vendor documentation · Incorrect caller ID displayed to the recipient
Cite this note
APA
WarmTransfer. (2026, September 30). Troubleshooting SIP 403 Forbidden from a carrier: source note sip-403-forbidden-troubleshooting-ms-from-pai. WarmTransfer. https://warmtransfer.net/knowledge/claims/sip-403-forbidden-troubleshooting-ms-from-pai
BibTeX
@misc{warmtransfer-claim-sip-403-forbidden-troubleshooting-ms-from-pai,
title = {Troubleshooting SIP 403 Forbidden from a carrier: source note sip-403-forbidden-troubleshooting-ms-from-pai},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/claims/sip-403-forbidden-troubleshooting-ms-from-pai},
note = {Source note sip-403-forbidden-troubleshooting-ms-from-pai, checked 2026-09-30}
}