Research on Key Management for Multi-privileged Group Communications

In some group-oriented applications, users can access several data resources according to their respective willingness. So, how to effectively access the data resources is a challenge in multi-privileged group communications. Some key management schemes for hierarchical access control are proposed. In this paper, we discuss the challenges of key management. Then, we present a list of evaluation criteria for secure key management for multi-privileged group communications, and investigate the features of some typical schemes. The schemes can be divided into several classes according to some separate dimensions, such as the topology of key model, the rekeying method, the rekeying policy and the encryption method of data resources. We analyze them comparatively regarding to the secure distribution and renewal of key materials.