An adaptable and scalable group access control scheme for managing wireless sensor networks

Access control is a prime technology to prevent unauthorized access to private information, which is one of the essential issues appearing in secure group communication (SGC) of wireless sensor networks (WSNs). Many studies have made good progress on access control; however, their methods are inadequate to cope with this new issue for SGC-based WSNs since of their inflexibility, inefficiency, insecurity, or small-scale. This paper, based on cryptographic theory, develops a scheme to manage the group access key used in SGC-based WSNs. In comparison with previous studies, the proposed method provides two main advantages. First, regarding adaptability, the administrator can assign access privilege flexibly, regardless of whether the relation among entities is hierarchical, peer-to-peer or heterogeneous. Second, regarding scalability, when an entity joins or leaves such a WSN, the administrator can re-generate the secure filter function alone and then send it to the entities (i.e., sensor nodes or base stations). While receiving this new secure filter function, the existing entities merely need to compute hash computation once to obtain the updating group access key, despite operating in an incremental system with a large number of entities.