An efficient hierarchical key management scheme using symmetric encryptions

The concept of hierarchical access control is that a higher privileged user (or higher level) has the ability to access data in lower privileged user (or lower level). Hierarchical key management scheme is used to accomplish this concept. Each user has its secret key which is used to protect data. User at higher level can compute the secret key of a user at lower level, but the counter measurement is infeasible. There have been many proposed solutions. In this paper, we introduce an efficient way using symmetric key cryptosystem to reduce the time of generating and deriving keys in hierarchical key management, and we show that the proposed scheme retains the same security level.