Source note · SIP OPTIONS pings and trunk keepalives
Microsoft describes the Direct Routing OPTIONS exchange in this order: the SBC opens TLS to the SIP proxy FQDN, the SBC sends OPTIONS, the proxy identifies the SBC FQDN and answers 200 OK on the same TLS connection, the proxy sends OPTIONS to the Contact FQDN, the SBC answers 200 OK, and the SBC is marked Active in the Teams admin center.
Checked 2026-09-24
- Vendor
- Microsoft
- Product
- Teams Phone Direct Routing
- Subsystem
- SIP proxy
- Deployment
- multi-tenant
- Region
- not restricted
- Release range
- current as of 2026-09-24
- Checked
- 2026-09-24
Sources
- SBC connectivity issues — Microsoft · tier 2 current vendor documentation · section 'Overview of the SIP options process', bullets 1-7
Cite this note
APA
WarmTransfer. (2026, September 24). SIP OPTIONS pings and trunk keepalives: source note sip-options-keepalive-dr-options-sequence. WarmTransfer. https://warmtransfer.net/knowledge/claims/sip-options-keepalive-dr-options-sequence
BibTeX
@misc{warmtransfer-claim-sip-options-keepalive-dr-options-sequence,
title = {SIP OPTIONS pings and trunk keepalives: source note sip-options-keepalive-dr-options-sequence},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/claims/sip-options-keepalive-dr-options-sequence},
note = {Source note sip-options-keepalive-dr-options-sequence, checked 2026-09-24}
}