Source note · Call transfer semantics REFER and Replaces
An attended transfer's Refer-To carries an escaped Replaces, which contains both a question mark separating the header from the URI and semicolons separating the dialog tags, so under RFC 8217 that Refer-To must be written in the name-addr form with angle brackets rather than as a bare address.
inferred · Checked 2026-09-16
- Vendor
- IETF
- Product
- Session Initiation Protocol
- Subsystem
- REFER
- Deployment
- not restricted
- Region
- not restricted
- Release range
- Updates RFC 3515
- Status
- inferred
- Checked
- 2026-09-16
Sources
- RFC 8217 — Clarifications for When to Use the name-addr Production in SIP Messages — IETF / RFC Editor · tier 1 standards and regulators · RFC 8217 section 4, read against the attended transfer Refer-To of RFC 5589 section 7.3
Cite this note
APA
WarmTransfer. (2026, September 16). Call transfer semantics REFER and Replaces: source note xfersem-attended-refer-to-needs-brackets. WarmTransfer. https://warmtransfer.net/knowledge/claims/xfersem-attended-refer-to-needs-brackets
BibTeX
@misc{warmtransfer-claim-xfersem-attended-refer-to-needs-brackets,
title = {Call transfer semantics REFER and Replaces: source note xfersem-attended-refer-to-needs-brackets},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/claims/xfersem-attended-refer-to-needs-brackets},
note = {Source note xfersem-attended-refer-to-needs-brackets, checked 2026-09-16}
}