Web service-based trust management in cloud environments

Trust is one of the most concerned obstacles for the adoption and growth of cloud computing. Although several solutions have been proposed recently in managing trust feedbacks in cloud environments, how to determine the credibility of trust feedbacks is mostly neglected. In addition, guaranteeing the availability of the trust management service is a difficult problem due to the unpredictable number of cloud service consumers and the highly dynamic nature of cloud environments. In this chapter, we propose a framework that uses Web services to improve ways on trust management in cloud environments. In particular, we introduce an adaptive credibility model that distinguishes between credible and malicious feedbacks by considering the cloud service consumers’ capability and majority consensus of their feedbacks. We also present a replication determination model that dynamically decides the optimal replica number of the trust management service so that the trust management service can be always maintained at a desired availability level. The approaches have been validated by a prototype system and experimental results.Talal H. Noor and Quan Z. Shen