CAPF listens on TCP 3804 to issue Locally Significant Certificates to IP phones.
Checked 2026-10-01
- Vendor
- Cisco
- Product
- Unified Communications Manager
- Subsystem
- CAPF
- Deployment
- on-premises
- Region
- not restricted
- Release range
- 15 and SUs
- Checked
- 2026-10-01
Sources
- System Configuration Guide for Cisco Unified Communications Manager, Release 15 and SUs - Cisco Unified Communications Manager TCP and UDP Port Usage — Cisco Systems · tier 2 current vendor documentation · Table: Signaling, Media, and Other Communication Between Phones and Cisco Unified Communications Manager, row TCP 3804
Cite this note
APA
WarmTransfer. (2026, October 1). Troubleshooting phone trust and ITL failures in Unified CM: source note cucm-itl-trust-troubleshooting-capf-port-3804. WarmTransfer. https://warmtransfer.net/knowledge/claims/cucm-itl-trust-troubleshooting-capf-port-3804
BibTeX
@misc{warmtransfer-claim-cucm-itl-trust-troubleshooting-capf-port-3804,
title = {Troubleshooting phone trust and ITL failures in Unified CM: source note cucm-itl-trust-troubleshooting-capf-port-3804},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/claims/cucm-itl-trust-troubleshooting-capf-port-3804},
note = {Source note cucm-itl-trust-troubleshooting-capf-port-3804, checked 2026-10-01}
}