Abstract Models

The main elements of abstract models are classes providing an abstraction of the specialties of real environments. This contrasts the components of environmental models, which deal with objects directly mappable to the real world. The dependencies between the classes are specified on the same level of abstraction. It is easy to see that environmental models actually are instantiations of abstract models--of their objects as well as their dependencies.

Simple Abstract Service Dependency Graph 

Abstract models are normally generated by hand--either by the vendor of the corresponding objects in the real world (e.g., the developer of an application provides a model showing the dependencies to other applications and the underlying system), or by the suppliers of management tools that are based on reasoning on such models. Just like environmental models, abstract models are suitable to express knowledge about higher layers, e.g., to model services. They do not depend on environmental specifics, but only express general or principal dependencies.

The model shown in figure looks similar to the previous one. However--as each node now depicts a class--both web clients are covered by a single ``web client'' element. Following object oriented principles, the nodes' and edges' attributes are now replaced by definitions for allowed, resp. needed attributes.