面向Web服务的动态可信性评估模型

网络化软件是由分布在互联网上多源异构的Web服务构成，但受其所处动态开放网络环境的影响，服务可信性处在不断变化之中.针对传统Web服务可信性难以适应动态评估的问题，提出了一种基于信息熵权重和带修正指标的动态信任评估模型（Dynamic Trustworthy Evaluation based on Information Entropy and Correction Metrics，DTEIECM）.首先，该模型充分挖掘模糊矩阵中的客观信息，利用信息熵对易受人为因素影响的主观权重进行修正.同时，考虑到所处运行环境对当前服务可信性的影响，增加了修正指标和受反馈影响的外部指标，以提高评估模型的自适应性.最后，通过对一个商务订单管理系统中的地图服务进行实例分析，结果表明DTMIECM模型在可信性度量中具有可行性，而且能够适应多变的环境并重新配置服务组合，有利于提高整个系统的可信度.

Dynamic Trustworthy Evaluation Model for Web Service

The networked software is composed of heterogeneous Web services which are distributed on the Internet. Service trustworthiness is in constant change under the influence of dynamic and open environment. To solve the problem that Web service trustworthy evaluation is difficult to adapt dynamic environment, this study developed a dynamic trustworthy evaluation based on information entropy and correction metrics. It mined deeply the objective information in fuzzy matrix and modified the subjective weights that are susceptible to human factors. Considering the impact of the running environment on the trustworthiness of the current service, it added correction metrics and external metrics affected by feedback to improve self-adaptability of the evaluation model. Finally, simulation experiments based on a map service show that the DTMIECM model possesses feasibility in trustworthy measurement. It can adapt to unstable environment and reconfigure service to improve trustworthiness of the whole system.