Enforcing Access Control in Virtual Organizations Using Hierarchical Attribute-Based Encryption

Virtual organizations are dynamic, interorganizational collaborations that involve systems and services belonging to different security domains. Several solutions have been proposed to guarantee the enforcement of the access control policies protecting the information exchanged in a distributed system, but none of them addresses the dynamicity characterizing virtual organizations. In this paper we propose a dynamic hierarchical attribute-based encryption (D-HABE)scheme that allows the institutions in a virtual organization to encrypt information according to a policy in such a way that only users with appropriate attributes can decrypt it. In addition, we introduce a key management scheme that determines which user is entitled to receive which attribute key from which domain authority.