Source note · SIP session timers
If no refresh arrives, the non-refresher should send BYE slightly before expiry, recommended at the lesser of 32 seconds and one third of the interval before it.
Checked 2026-09-25
The minimum of 32 seconds and one third of the session interval is RECOMMENDED.
- Vendor
- IETF
- Product
- SIP
- Subsystem
- expiry handling
- Deployment
- on-premises, multi-tenant, hybrid
- Region
- not restricted
- Release range
- RFC 4028
- Checked
- 2026-09-25
Sources
- RFC 4028: Session Timers in the Session Initiation Protocol (SIP) — IETF / RFC Editor · tier 1 standards and regulators · Section 10 (Performing Refreshes)
Cite this note
APA
WarmTransfer. (2026, September 25). SIP session timers: source note sip-session-timers-bye-before-expiry. WarmTransfer. https://warmtransfer.net/knowledge/claims/sip-session-timers-bye-before-expiry
BibTeX
@misc{warmtransfer-claim-sip-session-timers-bye-before-expiry,
title = {SIP session timers: source note sip-session-timers-bye-before-expiry},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/claims/sip-session-timers-bye-before-expiry},
note = {Source note sip-session-timers-bye-before-expiry, checked 2026-09-25}
}