访问控制策略中信息流的最优化去环方法

摘要

最优化去除访问控制中信息流的环路是许多重要信息系统向多级安全系统迁移时保证系统可用性的重要前提.证明了该问题是NP难题,提出了基于动态规划的最优解算法,利用遗传算法搜索近似最优解.复杂度分析和实验结果表明,对于小规模环境,最优解方法能较快地找出最优解；对于大规模环境,近似最优解算法能有效找出近似解.%Optimal eliminating cycles in Information flow of authorization policies is an important prerequisite to the success of migrating important information systems to multi-level security systems. This paper firstly proves it is a NP-hard problem, then presents optimization algorithm based on dynamic programming and approximate optimization algorithm based on genetic algorithm. Computational complexity analysis and experiments show that the former is fast to find the optimal solution in small-scale environment, the latter is effective to find the approximate optimal solution in large-scale environment.