NE's Role in an Object Model

NEs in an object model are distinguished by their role and their position. The position of an NE is its location relative to the other NEs in the model while its role is the part it plays in the model.

The DNE allows you to designate to each NE one of a number of roles. The roles that an NE can take is a function of the type of object model that is constructed: in a different model, different roles can be assigned. The role an NE plays is  distinguished graphically by a role indicator in the top right corner of the fields area.

A role is assigned to an NE by adding a graphic to the NE in a particular object model. Fields for NEs are object model-specific, so you can include information specific to the model.

By assigning a role to an NE, you enable the NE for inclusion in a model. NEs are attached to one another in a model according to various rules of connectivity, and whether a pair of NEs can or cannot directly connect one to another is determined by applying these connectivity rules in light of the roles of each of the NEs.