By default an inbound call that fails the IP trusted list check is silently discarded rather than answered with an error.

Checked 2026-09-25

Vendor
Cisco
Product
Cisco Unified Border Element
Subsystem
toll-fraud prevention
Deployment
on-premises
Region
not restricted
Release range
current as of 2026-09-25
Checked
2026-09-25

Sources

Cite this note

APA

WarmTransfer. (2026, September 25). Setting up CUBE for a carrier SIP trunk: source note cube-carrier-trunk-setup-untrusted-silent-discard. WarmTransfer. https://warmtransfer.net/knowledge/claims/cube-carrier-trunk-setup-untrusted-silent-discard

BibTeX

@misc{warmtransfer-claim-cube-carrier-trunk-setup-untrusted-silent-discard,
  title  = {Setting up CUBE for a carrier SIP trunk: source note cube-carrier-trunk-setup-untrusted-silent-discard},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/cube-carrier-trunk-setup-untrusted-silent-discard},
  note   = {Source note cube-carrier-trunk-setup-untrusted-silent-discard, checked 2026-09-25}
}

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