基于环境感知的可信QoS评价与服务选取策略

面向服务计算网络中,迫切需要对服务实体的QoS与可信性做出客观的评价.针对服务实体QoS的评价通常只是基于对用户感知到的QoS一种加权,不能客观反映实际网络环境下服务实体所能够提供的QoS问题,论文结合服务实体实际服务组合环境来表征服务实体的QoS,提出了一种基于环境感知的可信QoS评价与服务选取策略:(1)采用不同负载下的QoS特征向量来表征服务实体的QoS;(2)建立一种受限于可信实体的信任推理与演化机制,有效避免信任演化机制中信任泛化问题;(3)基于可信实体演化推导服务实体的可信度与QoS的特征向量;(4)结合当前的服务负载情况,较为客观地评价服务实体实际所能够提供的QoS.论文最后给出了综合的可信QoS评价与服务选取算法,实验结果表明了策略的有效性.

A Policy for the Trusted QoS Evaluation and Service Selection with Environment Aware

In service-oriented computing networks,it is urgently needed to objectively evaluate service entity’s QoS.In previous studies,service entity’s QoS is only a weighted QoS that is perceived by users.It cannot objectively reflect the QoS that the service entity can provide in actual network environment.Combined with the actual service composition environment of service entities to characterize QoS of the service entity,a policy for the trusted QoS evaluation and service selection with environment aware is proposed:(1) the QoS of service entity is characterized with different load QoS feature vectors;(2) a trust reasoning and evolution mechanism subjected to trusty entity is established to effectively avoid the shortage of creditable generalization in the trust evolution mechanism;(3) the creditability of service entities and QoS feature vector are deduced based on service entities through the trust evolution;(4) combined with the current service load,a more objective evaluation of QoS that service entities actually provide is obtained.Finally,an integrated trusted QoS evaluation and service selection algorithm is given.Experimental results demonstrate the effectiveness of the policy.