摘要： 在基于角色的访问控制（RBAC）模型的实现系统中，考虑到查询操作远多于修改操作，文章引入缓存机制，通过记录历史数据以提高后续查找的效率。讨论了4 种缓存策略，给出了相应的缓存算法，并对算法的优劣进行了比较。在一个实际的访问控制系统WebDaemon 中使用了缓存机制，证明查询效率得到了明显的提高。

关键词: 基于角色的访问控制；缓存；网络安全

Abstract: In implementations of role-based access control (RBAC) models, considering that query operations are far more than modification operations, this paper introduces cache strategy to improve the overall efficiency of subsequent queries by using historical queries. Four cache strategies are discussed, and the algorithms are given to each cache strategy respectively, and then it compares these cache algorithms. It uses cache mechanism in WebDaemon, a role-based access control system, which improves query efficiency remarkably.

Key words: Role-based access control; Cache; Network security