The Common Information Model categorizes information from general to specific. Specific information, such as a representation of the Solaris environment, extends the model. CIM consists of the following three layers of information:
Core Model - A subset of CIM not specific to any platform.
Common Model - Information model that visually depicts concepts, functionality, and representations of entities related to specific areas of network management, such as systems, devices, and applications.
Extensions - Information models that support the CIM Schema and represent a very specific platform, protocol, or corporate brand.
The Core Model provides the underlying, general assumptions of the managed environment--for example, that specific, requested data must be contained in a location and distributed to requesting applications or users. These assumptions are conveyed as a set of classes and associations that conceptually form the basis of the managed environment. The Core Model is meant to introduce uniformity across schemas intended to represent specific aspects of the managed environment.
For applications developers, the Core Model provides a set of classes, associations, and properties that can be used as a starting point to describe managed systems and determine how to extend the Common Model. The Core Model establishes a conceptual framework for modeling the rest of the managed environment.
The Core Model provides classes and associations to extend specific information about systems, applications, networks, devices, and other network features through the Common Model and extensions.
Areas of network management depicted in the Common Model are independent of a specific technology or implementation but provide the basis for the development of management applications. This model provides a set of base classes for extension into the area of five designated technology-specific schemas: Systems, Devices, Applications, Networks, and Physical.