RFC 6026 defines Timer M as 64*T1: the time an INVITE client transaction stays in the Accepted state, waiting for 2xx retransmissions or for further 2xx responses from other branches of a forked INVITE.

Checked 2026-09-25

Vendor
IETF
Product
SIP
Subsystem
timers
Deployment
any
Region
not restricted
Release range
RFC 6026 and later
Checked
2026-09-25

Sources

Cite this note

APA

WarmTransfer. (2026, September 25). Calls that drop after about 30 seconds: source note sip-calls-drop-30-seconds-timer-m. WarmTransfer. https://warmtransfer.net/knowledge/claims/sip-calls-drop-30-seconds-timer-m

BibTeX

@misc{warmtransfer-claim-sip-calls-drop-30-seconds-timer-m,
  title  = {Calls that drop after about 30 seconds: source note sip-calls-drop-30-seconds-timer-m},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/sip-calls-drop-30-seconds-timer-m},
  note   = {Source note sip-calls-drop-30-seconds-timer-m, checked 2026-09-25}
}

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