Analysis and design of distributed hierarchical access control for multimedia networks

To efficiently and effectively achieve the hierarchical access control for multimedia networks, in this paper we propose a distributed key management scheme whereby each SG (service group) maintains an SG server and give detailed analysis. In the proposed scheme, the server for a SG is utilized to manage the key tree and provide the related session keys for all the users in this SG. A detailed case study is provided, and we show that the communication overhead can be greatly reduced by O (n_O · log_dn_O), where n_O is the number of users in a SG, compared with employing an integrated key graph to the hierarchical access control problem. At the same time, the storage overhead for all users can be reduced by O(N), where N is the total number of users.