Source note · Call transfer semantics REFER and Replaces
In a basic transfer the signalling relationship between the Transferor and the Transferee is not terminated, so the call is recoverable if the Transfer Target cannot be reached, and RFC 5589's flows keep that dialog connected on hold throughout the REFER process.
Checked 2026-09-16
- Vendor
- IETF
- Product
- Session Initiation Protocol
- Subsystem
- Basic transfer
- Deployment
- not restricted
- Region
- not restricted
- Release range
- BCP 149
- Checked
- 2026-09-16
Sources
- RFC 5589 — Session Initiation Protocol (SIP) Call Control - Transfer — IETF / RFC Editor · tier 1 standards and regulators · RFC 5589 section 6, opening paragraph and the note preceding Figure 1
Cite this note
APA
WarmTransfer. (2026, September 16). Call transfer semantics REFER and Replaces: source note xfersem-basic-transfer-is-recoverable. WarmTransfer. https://warmtransfer.net/knowledge/claims/xfersem-basic-transfer-is-recoverable
BibTeX
@misc{warmtransfer-claim-xfersem-basic-transfer-is-recoverable,
title = {Call transfer semantics REFER and Replaces: source note xfersem-basic-transfer-is-recoverable},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/claims/xfersem-basic-transfer-is-recoverable},
note = {Source note xfersem-basic-transfer-is-recoverable, checked 2026-09-16}
}