RFC 3398 maps ISUP cause 17 (user busy) to SIP 486 Busy Here.

Checked 2026-09-24

Vendor
IETF
Product
SIP-ISUP interworking
Subsystem
cause mapping
Deployment
any
Region
not restricted
Release range
RFC 3398
Checked
2026-09-24

Sources

Cite this note

APA

WarmTransfer. (2026, September 24). Carrier escalation evidence packages: source note carrier-escalation-evidence-isup-cause-17-486. WarmTransfer. https://warmtransfer.net/knowledge/claims/carrier-escalation-evidence-isup-cause-17-486

BibTeX

@misc{warmtransfer-claim-carrier-escalation-evidence-isup-cause-17-486,
  title  = {Carrier escalation evidence packages: source note carrier-escalation-evidence-isup-cause-17-486},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/carrier-escalation-evidence-isup-cause-17-486},
  note   = {Source note carrier-escalation-evidence-isup-cause-17-486, checked 2026-09-24}
}

Read in context