Four timers are scoped to an unreliable transport and become 0 on a reliable one: A and E do not retransmit at all and D I J and K wait 0 seconds instead of their unreliable values.

fact · verified 2026-09-15

Vendor
IETF
Product
Session Initiation Protocol
Subsystem
transaction timers
Deployment
not restricted
Region
not restricted
Release range
current as of 2026-09-15
Status
fact
Confidence
0.90
Verified
2026-09-15

Sources

Cite this claim

APA

WarmTransfer. (2026, September 15). SIP retransmission timers and transaction state: claim siprt-transport-decides-whether-a-timer-runs. WarmTransfer. https://warmtransfer.net/knowledge/claims/siprt-transport-decides-whether-a-timer-runs

BibTeX

@misc{warmtransfer-claim-siprt-transport-decides-whether-a-timer-runs,
  title  = {SIP retransmission timers and transaction state: claim siprt-transport-decides-whether-a-timer-runs},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/siprt-transport-decides-whether-a-timer-runs},
  note   = {Claim siprt-transport-decides-whether-a-timer-runs, verified 2026-09-15}
}

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