基于信任度变化趋势的云服务选择模型

针对云服务选择过程中,用户难以选择可信、可用、可靠的云服务问题,本文提出一种基于信任度变化趋势,并结合QoS服务质量的云服务选择模型.首先,信任度的计算分为两部分,一部分根据贝叶斯原理计算信任度值,另一部分是将历史信任度值进行最小二乘的拟合,得到能更准确地反映信任度值的变化趋势值,根据信任度变化趋势值对信任度值进行修正,确定其综合信任度值.然后,根据云服务的QoS量化模型,计算得到客观的QoS值,在此基础上,引入了信息熵的概念来确定可信参数加权的问题,从而得到最优的服务选择.仿真实验表明,该模型能够体现云服务主体信任度的变化,增强云服务选择的预判能力,有效地提高服务选择的成功率.

Cloud Service Selection Model Based on Trust Trend

In order to improve the efficiency of cloud service selection and to guarantee trustworthy, available and reliable cloud service, a new model of cloud service selection based on trust trend was proposed. Base on this model, we firstly calculated the determined trust value in two parts: trust value and trust trend value (TTV). Trust value was calculated with Bayes theorem. Trust trend value was calculated with least squares linear regression. Trust trend value aims to illustrate the trust trend of changes in a given period. Then, we obtained the objective QoS value in the QoS quantitative model of could services. At the same time, the measuring strategy of trust relationship among cloud services was designed based on information entropy. The experiment result shows that this method can reflect changes in trust cloud services, enhance the predictive ability and effectively improve the success rate of cloud service selection.