A novel key management scheme for dynamic access control in a user hierarchy

Considering the solution of dynamic access problems in a user hierarchy, a novel scheme based on one-way hash function is proposed to manage the cryptographic keys in the paper. The scheme attempts to achieve both efficiency and non-iteration in deriving the successor's secret key. Besides, the other issues in relation with dynamic access control problems, such as adding/deleting classes, adding/deleting relationships and changing secret keys, can be held good to the scheme. In view of security, a competent Central Authority must provide the user a convenient way to change his/her key at any time; therefore, the design toward the algorithm in the paper contains such a function. What weight to mention especially among these characteristics of the scheme is the simplification of procedure in changing the private key, and no other current keys need altering simultaneously.