云计算环境下服务信任评估方法研究

Research on Service Trust Evaluation Approach under Cloud Computing Environment

云计算环境中,服务资源广域分布、复杂多变,服务实体之间的信任关系因不确定性强而难以有效建立与维护。传统的服务信任评估方法无法全面反映信任的随机性和模糊性特征。在研究云模型理论的基础上,提出一种基于加权多属性云的服务信任评估方法。引入时间衰减因子来反映服务信任的时效性,并以多属性信任云来细化信任评估的粒度。计算用户评价相似度,确定推荐实体的推荐可靠性和权重,防止不法分子的合谋欺骗和恶意攻击。通过云相似度计算确定服务的信任等级,为用户的服务选择提供安全决策。仿真结果表明,该方法明显提高了服务交互成功率,并能有效适用于云计算环境下的服务信任评估。

In cloud computing,the resources of service are widely distributed,complex and fickle.The trust relationship among service entities is hard to establish and maintain with high uncertainty.The characteristics of randomness and fuzziness of services cannot be responded by traditional trust evaluation approach comprehensively,so a service trust evaluation method based on weighted multi-attribute cloud was proposed.Time decay factor was introduced to reflect the timeliness of trust,and multi-attribute trust cloud was used to refine the evaluation granularity.In order to prevent conspiracy to defraud and malicious attacks,the reliability and weight of recommender were confirmed by similarity of evaluation,and the trust rating was confirmed by cloud similarity calculation to provide security decisions for the user＇s services selection.Simulation results show that this method can improve the success rate of services interaction obviously,and it can be applied to service trust evaluation under cloud computing environment.