CUCM Integration Overview_v3.8.4
Velocity integrates with Cisco Unified Call Manager (CUCM) to provide a reliable, secure, and manageable HTTPS service request for successful handshake and communication. The service request must be registered and subscribed with all HTTP/HTTPS supported VoIP Phones connected to CUCM.
It is recommended to use HTTPS since HTTPS uses TLS to encrypt HTTP requests and responses.