RFC 3665 Sections 3.8 to 3.11 give reference flows for unsuccessful sessions: no answer, busy, no response from the user agent, and temporarily unavailable.

Checked 2026-09-23

Vendor
IETF
Product
SIP
Subsystem
call-flow-examples
Deployment
multi-tenant, on-premises
Region
not restricted
Release range
December 2003
Checked
2026-09-23

Sources

Cite this note

APA

WarmTransfer. (2026, September 23). SIP trace capture and ladder analysis: source note sip-trace-analysis-rfc3665-failure-flows. WarmTransfer. https://warmtransfer.net/knowledge/claims/sip-trace-analysis-rfc3665-failure-flows

BibTeX

@misc{warmtransfer-claim-sip-trace-analysis-rfc3665-failure-flows,
  title  = {SIP trace capture and ladder analysis: source note sip-trace-analysis-rfc3665-failure-flows},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/sip-trace-analysis-rfc3665-failure-flows},
  note   = {Source note sip-trace-analysis-rfc3665-failure-flows, checked 2026-09-23}
}

Read in context