Constraints validation in privacy-preserving attribute-based access control

Attribute-Based Access Control (ABAC) has been found to be extremely useful and flexible and has drawn a lot of research in recent years. It was observed that in the context of new emerging applications, attributes play an increasingly important role both in defining and enforcing more elaborated and flexible security policies. Recently, NIST has proposed more formal definition of ABAC. In this paper we discuss a general privacy-preserving ABAC model (which combines both authentication and authorization) and propose an approach to handle constraints in such privacy preserving setting.