Unified CM documents a restriction: when several non-secure SIP trunks with different listening ports point to the same destination or port, they may use the wrong port in a mid-call INVITE and the call drops.

Checked 2026-09-24

When multiple non-secure SIP trunks with different listening ports point to the same destination or port, they may incorrectly use the port in the mid call INVITE.
Vendor
Cisco
Product
Unified Communications Manager
Subsystem
SIP trunk restrictions
Deployment
on-premises
Region
not restricted
Release range
Release 15 and SUs
Checked
2026-09-24

Sources

Cite this note

APA

WarmTransfer. (2026, September 24). Unified CM SIP trunks and security profiles: source note cucm-sip-trunks-nonsecure-multiport-call-drop. WarmTransfer. https://warmtransfer.net/knowledge/claims/cucm-sip-trunks-nonsecure-multiport-call-drop

BibTeX

@misc{warmtransfer-claim-cucm-sip-trunks-nonsecure-multiport-call-drop,
  title  = {Unified CM SIP trunks and security profiles: source note cucm-sip-trunks-nonsecure-multiport-call-drop},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/cucm-sip-trunks-nonsecure-multiport-call-drop},
  note   = {Source note cucm-sip-trunks-nonsecure-multiport-call-drop, checked 2026-09-24}
}

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