关键词: 存取控制 离散对数 多项式内插 用户层次结构

Abstract:

In the problem of dynamic access control, we present a secure and efficient scheme, which is based on discrete logarithms and polynomial interpolation  . In our scheme, when a user at a higher level is absent, a certain user at a lower level can replace him and take the part of his privilege, and when t he user at a higher level comes back, he can call back his privileg.

Key words: access control, discrete logarithm, polynomial interpolation, user hierarchy