With media bypass, Direct Routing does not strip non-audio m-lines (for example m=video on a forwarded video call), so the SBC must answer each non-audio m-line with port zero per RFC 3264 to reject it.
Checked 2026-09-30
- Vendor
- Microsoft
- Product
- Microsoft Teams Phone Direct Routing
- Subsystem
- SBC SDP handling
- Deployment
- multi-tenant
- Region
- not restricted
- Release range
- current as of 2026-09-30
- Checked
- 2026-09-30
Sources
- Direct Routing support for media bypass - Microsoft Teams — Microsoft Learn · tier 2 current vendor documentation · Scenarios > Handling M lines in SDP
Cite this note
APA
WarmTransfer. (2026, September 30). Setting up media bypass and local media optimization for Teams Direct Routing: source note teams-media-bypass-setup-sdp-mlines. WarmTransfer. https://warmtransfer.net/knowledge/claims/teams-media-bypass-setup-sdp-mlines
BibTeX
@misc{warmtransfer-claim-teams-media-bypass-setup-sdp-mlines,
title = {Setting up media bypass and local media optimization for Teams Direct Routing: source note teams-media-bypass-setup-sdp-mlines},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/claims/teams-media-bypass-setup-sdp-mlines},
note = {Source note teams-media-bypass-setup-sdp-mlines, checked 2026-09-30}
}