Source note · SIP transactions dialogs and call setup
The originating user agent must generate an acknowledgement for each 2xx it receives with the same sequence number as the INVITE and the method set to acknowledge.
Checked 2026-09-15
- Vendor
- IETF
- Product
- Session Initiation Protocol
- Subsystem
- transactions
- Deployment
- not restricted
- Region
- not restricted
- Release range
- current as of 2026-09-15
- Checked
- 2026-09-15
Sources
- RFC 3261 — SIP: Session Initiation Protocol — IETF / RFC Editor · tier 1 standards and regulators · RFC 3261 section 13.2.2.4
Cite this note
APA
WarmTransfer. (2026, September 15). SIP transactions dialogs and call setup: source note siptx-uac-sends-an-ack-for-every-2xx. WarmTransfer. https://warmtransfer.net/knowledge/claims/siptx-uac-sends-an-ack-for-every-2xx
BibTeX
@misc{warmtransfer-claim-siptx-uac-sends-an-ack-for-every-2xx,
title = {SIP transactions dialogs and call setup: source note siptx-uac-sends-an-ack-for-every-2xx},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/claims/siptx-uac-sends-an-ack-for-every-2xx},
note = {Source note siptx-uac-sends-an-ack-for-every-2xx, checked 2026-09-15}
}