Key distribution scheme based on two cryptosystems for hierarchical access control
Bing Hu, Ye Wu, Suili Feng, Xiaoliang Wang, Xing Xie · 2006 8th International Conference Advanced Communication Technology · 2006
To combine the merits of symmetric key cryptosystem and public-key cryptosystem, the authors present a key distribution scheme based on both the Rabin public-key system and the Chinese remainder theorem (CRT) for conditional access system (CAS) in digital TV broadcast, in order to solve dynamic access control problems in user hierarchies. Due to the simplicity of key generation and derivation, the proposed scheme can greatly reduce the encrypting computation and transportation load in the meantime acquire high security. Dynamic access control problems, such as adding/deleting group, adding/deleting relationships and changing secret keys, are easily solved. The proposed scheme is also very suitable for the pay-per-view method