Source note · Passing call context with SIP UUI and custom headers

RFC 7433 defines only one value for the User-to-User 'encoding' parameter, 'hex'; other encodings are left to future packages.

Checked 2026-10-02

This specification only defines 'encoding=hex'

Vendor: not restricted
Product: not restricted
Subsystem: SIP User-to-User header
Deployment: any
Region: not restricted
Release range: RFC 7433
Checked: 2026-10-02

Sources

RFC 7433: A Mechanism for Transporting User-to-User Call Control Information in SIP — IETF / RFC Editor · tier 1 standards and regulators · Section 4 (encoding parameter)

Cite this note

APA

WarmTransfer. (2026, October 2). Passing call context with SIP UUI and custom headers: source note sip-uui-context-passing-rfc7433-hex-only-encoding. WarmTransfer. https://warmtransfer.net/knowledge/claims/sip-uui-context-passing-rfc7433-hex-only-encoding

BibTeX

@misc{warmtransfer-claim-sip-uui-context-passing-rfc7433-hex-only-encoding,
  title  = {Passing call context with SIP UUI and custom headers: source note sip-uui-context-passing-rfc7433-hex-only-encoding},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/sip-uui-context-passing-rfc7433-hex-only-encoding},
  note   = {Source note sip-uui-context-passing-rfc7433-hex-only-encoding, checked 2026-10-02}
}

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