Multidimensional Trust Model Based On Fuzzy Comprehensive Assessment Grid

Trust model has an important position in the network security problem. Along withemergence of grid technology, the user management isn’t central, closed and controllable.Traditional trust model can’t solve security problems faced in the grid. The trust problem in thegrid environment has become a hot issue in the current research on grid safety.Firstly, the research situation of trust model under distributed environment is analyzed;secondly, the advantages and disadvantages of the current trust models and involved issues aresummarized; finally, the multi-dimensional grid trust model based on virtual domain and fuzzycomprehensive evaluation is proposed with the definition and property and computation of thetrust, and the latter model is analyzed.In this paper, the main work is as follows:1. A multidimensional concept of trust is introduced into the trust model based on virtualdomain, a multi-dimensional grid trust model based on trust domain is proposed. Due to thedifferent target nodes have different service contents, so the computation of the trust of therequest nodes is more coincident the requirement of the target nodes from different aspects.2. In multi-dimensional trust model based on virtual domain, for the recommend trustwithin domain, if the neighbor node is known, the trust values of the target nodes is obtaineddirectly through the recommend of neighbor nodes; if the neighbor node is unknown, trust agentcould be a presenter directly, then the recommend node believes the recommended of trustagency totally. So the recommend burden of the trust agent can be reduced greatly. for therecommend trust between domain, the computation of recommend trust can be simplified, andthe consumption of the grid performance is reduced by using the method of the shortest pathmaximum trust.3. Due to the uncertainty and subjectivity of the trust, a multidimensional grid trust modelbased on fuzzy comprehensive evaluation decision is proposed; the uncertainty of grid trust isexpressed by using the fuzzy theory and the trust degree of request node with comprehensiveevaluation decision of fuzzy mathematics. In this model, the weights is computed by usingEuclidean closeness formula, so the trust weights of the recommendation node is more accurateand reasonable, and it can enhance the objectivity of trust values.