关键词: 信任评价, 基于任务&mdash, 角色的访问控制, 分布式系统, 模糊数学

Abstract: To realize secure sharing of information in distributed systems,a dynamic multi-step quantified trust evaluation algorithm was presented by combining fuzzy judgment with statistic theory,and a fine-grained Task-Role Based Access Control (T-RBAC) model based on multi-step quantified trust evaluation was constructed.The proposed multi-step quantified trust evaluation algorithm could dynamic measure the multiple elements of trust and assess trust value synthetically with execution context,which made the trust value accord with the characteristic of increasing slowly but decreasing rapidly,and have the ability of security attacks.Experiments and analyses showed that the T-RBAC model could improve the dynamic adaptability of trust with context changes and obtain the secure access control solution for large-scale distributed systems can be obtained.

Key words: trust evaluation, task-role based access control, distributed system, fuzzy mathematics