Claim record · SIP transactions dialogs and call setup
The branch parameter on the topmost routing header is the transaction identifier and must be unique across space and time for every request a user agent sends.
fact · verified 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
- Status
- fact
- Confidence
- 0.90
- Verified
- 2026-09-15
Sources
- RFC 3261 — SIP: Session Initiation Protocol — IETF / RFC Editor · tier 1 standards and regulators · RFC 3261 section 8.1.1.7
Cite this claim
APA
WarmTransfer. (2026, September 15). SIP transactions dialogs and call setup: claim siptx-branch-identifies-the-transaction. WarmTransfer. https://warmtransfer.net/knowledge/claims/siptx-branch-identifies-the-transaction
BibTeX
@misc{warmtransfer-claim-siptx-branch-identifies-the-transaction,
title = {SIP transactions dialogs and call setup: claim siptx-branch-identifies-the-transaction},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/claims/siptx-branch-identifies-the-transaction},
note = {Claim siptx-branch-identifies-the-transaction, verified 2026-09-15}
}