A trust evaluation method for dynamic distributed environment

In the distributed environment, the involved entities have the feature of dynamic changeable, these changes result in security problems in the entity´s reliable operation and the fair use of resources. To solve the security problems in dynamic distributed environment, in this paper, we propose a model of evaluating the trust degree of the dynamic entity according to distributed environment´s dynamic characteristic. Based on several critical concepts in trust mechanism, quantification is processed by using direct trust degree, indirect trust degree, trust weight, trust attenuation and so on, then a synthesize trust degree evaluating model (STDEM) is given and the evaluation parameters of each kind of trust degree are quantified, thus a scheme for evaluating the nodes´ creditability in the distributed system is provided in this paper. We analyze the parameters used in STDEM model through the simulations, and the effectiveness of model is validated by being applied to a specific distributed data system.