Modeling correlation between QoS attributes for trust computation in cloud computing environments

This paper introduces an approach that handles with the trustworthy cloud service selection issue in Cloud computing environments. Despite the fact that most of the existing trust systems consider several QoS attributes for trust computing, none of them did consider the correlation that may exist among these attributes. However, we demonstrate in this paper that the integration of correlation between QoS attributes in trust computing significantly helps to solve many issues such as predicting missing assessment, detecting malicious feedbacks and improving the accuracy of trust values. The main goal of this paper is to show the significance of correlation between those attributes for trust computing. To do that, we propose combining both the popular Naive Bayes model and the n-gram Markov model to design a more efficient trust model for cloud environments. Our proposed trust model also takes into account the user's requirements, aggregates both the qualitative and quantitative assessment, and considers several sources when computing cloud services' trust values. Experimental results show that our proposed approach outperforms the traditional Naive Bayes trust models.