Source note · Calls that drop after about 30 seconds
The Teams Direct Routing SIP proxy always offers the session timer on non-bypass calls, does not offer it on media-bypass calls, and does not require the SBC to use it.
Checked 2026-09-25
Use of the Session Timer by the SBC isn't mandatory.
- Vendor
- Microsoft
- Product
- Teams Phone Direct Routing
- Subsystem
- SIP proxy
- 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 · Section 'Session timer'
Cite this note
APA
WarmTransfer. (2026, September 25). Calls that drop after about 30 seconds: source note sip-calls-drop-30-seconds-msdr-session-timer. WarmTransfer. https://warmtransfer.net/knowledge/claims/sip-calls-drop-30-seconds-msdr-session-timer
BibTeX
@misc{warmtransfer-claim-sip-calls-drop-30-seconds-msdr-session-timer,
title = {Calls that drop after about 30 seconds: source note sip-calls-drop-30-seconds-msdr-session-timer},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/claims/sip-calls-drop-30-seconds-msdr-session-timer},
note = {Source note sip-calls-drop-30-seconds-msdr-session-timer, checked 2026-09-25}
}