Traditional access control mechanisms aim to prevent illegal actions a-priori occurrence, i.e. before granting a request for a document. There are scenarios however where the security decision can not be made on the fly. For these settings we developed a language and a framework for a-posteriori access control. In this paper we show how the framework can be used in a practical scenario. In particular, we work out the example of an Electronic Health Record (EHR) system, we outline the full architecture needed for audit-based access control and we discuss the requirements and limitations of this approach concerning the underlying infrastructure and its users.
M. A. C. Dekker, Sandro Etalle