A time- bound hierarchical access control for multicast systems

This scheme is based on elliptic curve multiplication property, bilinear pairing, one-way hash function, and the time-bound access control. It is applied to construct a time-bound hierarchical access control and key management for a multicast system. The system has many security classes and the CA is a central authority which assigns a group key and time-bound secret keys to every security class and all class members. CA uses different group keys to encrypt different multicast data. Then, the member decrypts the multicast data using a time-bound secret key to obtain a group key. In the security analysis, we consider many different possible malicious attacks by using the time-bound secret key and the group key. Finally, we simulate it to analyze the system security.