As part of the access control process an authorization decision needs to be taken based on a certain authorization model. Depending on the environment different models are applicable (e.g., RBAC in organizations, MAC in the military field). An authorization model contains all necessary elements needed for the decision (e.g., subjects, objects, and roles) as well as their relations. As these elements are usually inherent in the software architecture of an access control module, such modules limit themselves to the use of a certain specific authorization model. A later change of the model consequently results in a substantial effort for revising the software architecture of the given module. Rule-based systems are well suited to represent authorization models by mapping them to facts and rules, which can be modified in a flexible manner. In this paper
we present a generic authorization module, which can take authorization decisions on the basis of arbitrary models utilizing rule-based technology.
The implementation of the popular RBAC and ABAC (attribute-based access control) models is demonstrated.