1. A system for generating an enhancement of a request ontology, the system comprising: a memory unit configured to provide the request ontology and to store the request ontology with the enhancement; and a processing unit configured to: identify a service specification being represented by a class of the request ontology, the service specification describing a capability of a service, compute a set of instances that are specified by the service specification and by a requirement specification describing at least one characteristic for selecting the service that is independent of the class of the request ontology, enhance the request ontology with a generated class representing the computed set of instances specified by the service specification and by the requirement specification, wherein the generated class represents a condition part of a selection rule based on the at least one characteristic for selecting the service, and generate an action part of the selection rule using an identification of the service so that a relation between the generated class and the service is represented by the selection rule having the condition part and the action part, wherein the condition part of the selection rule specifies a condition based on the at least one characteristic for selecting the service and the action part of the selection rule specifies an action to be executed when the condition of the condition part is fulfilled.