A P-Asserted-Identity header carries at most two values, and if there are two, one must be a sip or sips URI and the other a tel URI.

Checked 2026-09-25

If there are two values, one value MUST be a sip or sips URI and the other MUST be a tel URI.
Vendor
IETF
Product
SIP
Subsystem
identity headers
Deployment
any
Region
not restricted
Release range
RFC 3325
Checked
2026-09-25

Sources

Cite this note

APA

WarmTransfer. (2026, September 25). Wrong or missing caller ID on outbound calls: source note caller-id-presentation-problems-pai-max-two-values. WarmTransfer. https://warmtransfer.net/knowledge/claims/caller-id-presentation-problems-pai-max-two-values

BibTeX

@misc{warmtransfer-claim-caller-id-presentation-problems-pai-max-two-values,
  title  = {Wrong or missing caller ID on outbound calls: source note caller-id-presentation-problems-pai-max-two-values},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/caller-id-presentation-problems-pai-max-two-values},
  note   = {Source note caller-id-presentation-problems-pai-max-two-values, checked 2026-09-25}
}

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