CIM Concepts

The following sections describe basic CIM terms and concepts that are essential to understanding how network entities and management functions are described and related within the context of CIM. For more detailed information about the Common Information Model and object-oriented modeling practices, including how to model your own schema, refer to the CIM Tutorial provided by the Distributed Management Task Force.

Object-Oriented Modeling

CIM uses the principles of Object-Oriented Modeling, a way to represent an object, entity, concept, or function that has a physical or logical existence. The goal of Object-Oriented Modeling is to set a representation of a physical entity into a framework, or model, to express the qualities and functions of the entity and its relationships with other entities. In the context of CIM, Object-Oriented Modeling is used to model hardware and software elements.

Uniform Modeling Language

Models are expressed in the form of visual representation and language. CIM conventions for rendering the model are based on the diagrammatic concepts of Uniform Modeling Language UML. UML uses shapes to represent physical entities and lines to represent relationships. For example, in UML, classes are represented as rectangles. Each rectangle contains the name of the class it represents. A line between two rectangle represents a relationship between the two. A line that forks to join two classes to a higher-level class represents an association.

CIM diagrams add color to the diagrams to further express relationships:

• Red lines->Associations

• Blue lines->Inheritance relationships

• Green lines->Aggregation