The next figure depicts instances of PerformanceCategories that are based on a PerformanceCategorySpecification. For example, a Codec specification has category instances of 243-PCMU, 230-GSM, and so forth.  Any number of category instances can be associated to a specification.<br/>Also shown in the figure is an association between a PerformanceCategory and itself and the association class PerformanceCategoryRelationship. The relationship is governed by the association between a PerformanceCategorySpecification and itself.  It defines associations that exist between categories.  For example, the Codec instance 243-GSM is related to the BearerType instance 999 and the MediaType instance 546.  These relationships further define the Codec instance in the example.<br/>