RFC 4320 finds that a 408 response to a non-INVITE request always arrives too late to be useful.

Checked 2026-09-25

A 408 to non-INVITE will always arrive too late to be useful
Vendor
not restricted
Product
SIP
Subsystem
transactions
Deployment
any
Region
not restricted
Release range
RFC 4320
Checked
2026-09-25

Sources

Cite this note

APA

WarmTransfer. (2026, September 25). SIP registration failures: source note sip-registration-failures-408-too-late. WarmTransfer. https://warmtransfer.net/knowledge/claims/sip-registration-failures-408-too-late

BibTeX

@misc{warmtransfer-claim-sip-registration-failures-408-too-late,
  title  = {SIP registration failures: source note sip-registration-failures-408-too-late},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/sip-registration-failures-408-too-late},
  note   = {Source note sip-registration-failures-408-too-late, checked 2026-09-25}
}

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