Direct Routing treats an SBC as healthy if it sent OPTIONS at some point in the last three minutes, which is three times the regular one-minute interval.

Checked 2026-09-24

If options were sent during the last three minutes, the SBC is considered healthy.
Vendor
Microsoft
Product
Teams Phone Direct Routing
Subsystem
SBC health monitoring
Deployment
multi-tenant
Region
not restricted
Release range
current as of 2026-09-24
Checked
2026-09-24

Sources

Cite this note

APA

WarmTransfer. (2026, September 24). SIP OPTIONS pings and trunk keepalives: source note sip-options-keepalive-dr-three-minute-window. WarmTransfer. https://warmtransfer.net/knowledge/claims/sip-options-keepalive-dr-three-minute-window

BibTeX

@misc{warmtransfer-claim-sip-options-keepalive-dr-three-minute-window,
  title  = {SIP OPTIONS pings and trunk keepalives: source note sip-options-keepalive-dr-three-minute-window},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/sip-options-keepalive-dr-three-minute-window},
  note   = {Source note sip-options-keepalive-dr-three-minute-window, checked 2026-09-24}
}

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