Phase: Architecture and Design
For front-end to back-end connections: Three solutions are possible, although none are complete.
The first suggestion involves the use of generated passwords or keys that are changed automatically and must be entered at given time intervals by a system administrator. These passwords will be held in memory and only be valid for the time intervals.
Next, the passwords or keys should be limited at the back end to only performing actions valid for the front end, as opposed to having full access.