Source note · Enabling mixed mode and encrypted calling in Unified CM
The CTL file on a phone can be checked under Settings > Security Configuration > Trust List > CTL File and its checksum compared with the output of show ctl.
Checked 2026-09-30
- Vendor
- Cisco
- Product
- Cisco Unified Communications Manager
- Subsystem
- verification
- Deployment
- on-premises
- Region
- not restricted
- Release range
- 10.x and later; phone menu labels vary by model and firmware
- Checked
- 2026-09-30
Sources
- CUCM Cluster Changed from Mixed Mode to Non-Secure Mode Configuration Example — Cisco Systems · tier 2 current vendor documentation · Verify
Cite this note
APA
WarmTransfer. (2026, September 30). Enabling mixed mode and encrypted calling in Unified CM: source note cucm-secure-calling-setup-phone-ctl-checksum. WarmTransfer. https://warmtransfer.net/knowledge/claims/cucm-secure-calling-setup-phone-ctl-checksum
BibTeX
@misc{warmtransfer-claim-cucm-secure-calling-setup-phone-ctl-checksum,
title = {Enabling mixed mode and encrypted calling in Unified CM: source note cucm-secure-calling-setup-phone-ctl-checksum},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/claims/cucm-secure-calling-setup-phone-ctl-checksum},
note = {Source note cucm-secure-calling-setup-phone-ctl-checksum, checked 2026-09-30}
}