Front Controller Pattern

Intent: A pattern where a system that processes user requests provides a single point of access to all of the clients (see the Wikipedia definition at http://en.wikipedia.org/wiki/Front_Controller_pattern). It doesn't appear in the GangOfFour book but seems pretty useful and similar to the MediatorPattern - Arieh Bibliowicz

How does this compare to ClientServer systems based on RDBMS?

CategoryPattern | CategoryStructuralPatterns