RFC 7044 (February 2014) defines the SIP History-Info header, which records how and why a request reached its target through retargeting such as forwarding, and it obsoletes RFC 4244.

Checked 2026-09-25

Vendor
IETF
Product
SIP
Subsystem
History-Info
Deployment
any
Region
not restricted
Release range
RFC 7044 onward
Checked
2026-09-25

Sources

Cite this note

APA

WarmTransfer. (2026, September 25). SIP call forwarding and routing loops: source note sip-forwarding-loops-history-info-purpose. WarmTransfer. https://warmtransfer.net/knowledge/claims/sip-forwarding-loops-history-info-purpose

BibTeX

@misc{warmtransfer-claim-sip-forwarding-loops-history-info-purpose,
  title  = {SIP call forwarding and routing loops: source note sip-forwarding-loops-history-info-purpose},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/sip-forwarding-loops-history-info-purpose},
  note   = {Source note sip-forwarding-loops-history-info-purpose, checked 2026-09-25}
}

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