Architecture Models

  Relations are the main idea relevant for security in this paper. A relation between two entities exists if they exchange any kind of information. An intruder either attacks an existing relation or an existing entity. In the latter case, he must establish a relation with his target. If there are no relations with others, an entity is isolated and thus not subject to attacks (certainly even isolated systems may be subject to attacks. However, this requires physical access to the system and is thus not considered in this paper). If there are relations security may become important.

To recognize attacks it is necessary to identify relations and entities participating in these relations. Knowing these entities it is possible to classify relations as specific forms of interactions. Finally, the functional components of these entities must be identified. These components are the actual points of attacks and thus have to implement security.