Attended transfer uses an escaped Replaces header field inside the Refer-To header so that the new Transferee-to-Target dialog replaces the Transferor-to-Target dialog.

Checked 2026-09-30

Vendor
IETF
Product
SIP
Subsystem
call-transfer
Deployment
any
Region
not restricted
Release range
RFC as published; BCP 149
Checked
2026-09-30

Sources

Cite this note

APA

WarmTransfer. (2026, September 30). Troubleshooting calls that drop on hold or transfer: source note sip-reinvite-call-drops-attended-transfer-replaces. WarmTransfer. https://warmtransfer.net/knowledge/claims/sip-reinvite-call-drops-attended-transfer-replaces

BibTeX

@misc{warmtransfer-claim-sip-reinvite-call-drops-attended-transfer-replaces,
  title  = {Troubleshooting calls that drop on hold or transfer: source note sip-reinvite-call-drops-attended-transfer-replaces},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/sip-reinvite-call-drops-attended-transfer-replaces},
  note   = {Source note sip-reinvite-call-drops-attended-transfer-replaces, checked 2026-09-30}
}

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