Source note · Calls that drop after about 30 seconds
Under RFC 3261, if a UAS retransmits its 2xx response to an INVITE for 64*T1 seconds without receiving an ACK, the dialog is confirmed but the session SHOULD be terminated with a BYE.
Checked 2026-09-25
- Vendor
- IETF
- Product
- SIP
- Subsystem
- INVITE transaction / UAS core
- Deployment
- any
- Region
- not restricted
- Release range
- RFC 3261 as updated by RFC 6026
- Checked
- 2026-09-25
Sources
- RFC 3261 — SIP: Session Initiation Protocol — IETF / RFC Editor · tier 1 standards and regulators · Section 13.3.1.4 (The INVITE is Accepted)
Cite this note
APA
WarmTransfer. (2026, September 25). Calls that drop after about 30 seconds: source note sip-calls-drop-30-seconds-uas-no-ack-bye. WarmTransfer. https://warmtransfer.net/knowledge/claims/sip-calls-drop-30-seconds-uas-no-ack-bye
BibTeX
@misc{warmtransfer-claim-sip-calls-drop-30-seconds-uas-no-ack-bye,
title = {Calls that drop after about 30 seconds: source note sip-calls-drop-30-seconds-uas-no-ack-bye},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/claims/sip-calls-drop-30-seconds-uas-no-ack-bye},
note = {Source note sip-calls-drop-30-seconds-uas-no-ack-bye, checked 2026-09-25}
}