# Requirements

Currently, using the Relu® hosted Engine requires having your own cloud infrastructure. Indeed, the authentication keys used to communicate with the Engine are secret and shouldn’t be exposed to your users. Otherwise, a user could use these keys to impersonate you and send job requests to our cloud on your behalf, leading to costs that you don’t control.

This is how your infrastructure should be set-up:

As shown above, the Relu authentication keys are only stored on your cloud, not on the local desktop apps of your users.