A Synthesize Trust Degree Evaluation method in distributed system

With the rapid and profound changes in computing technology, distributed computing, as an important branch of it, is becoming increasingly important, and gradually shifts from academia to specific areas of application. Currently, extensive researches on cloud computing, grid computing, large-scale E-Commerce web sites are all manifestations of a distributed system. Participating entities in a distributed environment have dynamic variable characteristics in the lifetime, which make the reliable operation of the entity and the rational use of resources face a security risk. The paper, stuck to the dynamic characteristics of a distributed environment, has proposed an evaluation model of Dynamic Entity Trust Degree to solve these security issues in a dynamic distributed environment. Based on a few key concepts of the trust mechanism, we quantified and proposed a Synthesize Trust Degree Evaluating Model (STDEM) by using Direct Trust Degree, Indirect Trust Degree, Trust Weight, Trust Attenuation, and specifically quantified the evaluation parameters for every kind of trust degree, providing an assessment for the credibility of the nodes in the distributed system. Parameters of the STDEM model were analyzed through simulation experiments and the STDEM was applied to specific data distributed systems with the validity of the model verified.