Efficient Sub-/Inter-Group Key Distribution for ad hoc Networks

People need to communicate each other in many emerging networks, i.e., in ad hoc networks. To ensure the security for group communication, group key management as a fundamental cryptographic primitive has been proposed. Although many proposals with regard to group key managemet have been introduced, they cannot be efficiently applied to realize secure subgroup and intergroup communications. In this paper, we propose two group key distribution schemes providing efficient solutions to these two problems. Our protocols do not require interaction between users. Storage and computation analyses show that our proposals are secure and efficient, compared with existing schemes. Based on those basic schemes, we further present extensions for multipartite groups, by which the efficiency is greatly improved in this scenario.