You can create a new information model or extend an existing one. In general, each information model should accommodate the data about a particular area of your application environment.
Follow these guidelines:
Repository prevents you from reusing a name for a class, interface, or relationship type within the same information model. You can, however, reuse a name in a different information model. When you create a new information model, choose your names carefully. Avoid naming confusion by using a distinctive prefix on all of your names. For example, all of the names in the Microsoft Development Objects Model are prefixed with the characters Mdo.