Source note · SIP session timers
The letter x is reserved as the compact form of the Session-Expires header.
Checked 2026-09-25
Note that a compact form, the letter x, has been reserved for Session-Expires.
- Vendor
- IETF
- Product
- SIP
- Subsystem
- Session-Expires header
- 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 4 (Session-Expires Header Field Definition)
Cite this note
APA
WarmTransfer. (2026, September 25). SIP session timers: source note sip-session-timers-compact-form-x. WarmTransfer. https://warmtransfer.net/knowledge/claims/sip-session-timers-compact-form-x
BibTeX
@misc{warmtransfer-claim-sip-session-timers-compact-form-x,
title = {SIP session timers: source note sip-session-timers-compact-form-x},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/claims/sip-session-timers-compact-form-x},
note = {Source note sip-session-timers-compact-form-x, checked 2026-09-25}
}