CuViBox on-premise is the CuViBox version you can try and install in your own servers.

CuViBox cloud is the web that you get when you access or your account subdomain

Apart of the user plan management, billing, account management,.. CuViBox on-premise and CuViBox on-cloud are exactly the same, they share code and features. 

If your enterprise privacy policies don't allow you to use the cloud version, you can still download and install CuViBox on-premise.