of implementations. CIM represents a managed environment as a collection of interrelated systems, each of which is composed of a set of discrete elements. The man- agement schema consists of management platforms and management appli- cations, like configuration management, performance management, and change management. The CIM schema supplies a set of classes with proper- ties and associations thus creating a conceptual framework centered on the schema class. The core and common model discussed later in this chapter, make up the CIM schema. 3. Class: The properties and the methods common to a particular kind of object are defined in CIM class. Each CIM class represents a managed element and is scoped by the schema in which it belongs. The class name should be unique for the schema in which the class belongs. Fundamentals of EMS, NMS and OSS/BSS 4. Property: It contains the properties describing the data of the CIM class. CIM property will have a name, data type, value, and an optional default value. Each property must be unique within the class. 5. Method: Methods describe the behavior of the class. A method can be invoked and includes a name, return type, optional input parameters, and optional output parameters. Methods must be unique within the class, as a class can have zero or more methods. Methods with these characteristics are termed CIM methods. The method parameter and return type must be one of the CIM supported data types. The IN or OUT qualifier specifies the parameter type to be input or output. 6. Qualifier: Values providing additional information about classes, associa- tions, indications, methods, method parameters, properties, or references are called a CIM qualifier. A qualifier can be used only with a qualifier type definition and the data type and value must match to that of the qualifier type. Qualifiers have a name, type, value, scope, flavor, and an optional default value. The scope of a qualifier is determined by the namespace in which it is present. The qualifier type definition is unique