Research Of Grid Trust Mechanism

Grid is a brand-new research field currently. The grid technology is a significant science advance after Internet. The research of grid origins from the high performance computation,magnanimous data processing and expensive scientific resources flexible sharing demand in modern science exploration. Compare to traditional network, the grid has many new characteristics as an important future infrastructure. The dynamic characteristic of grid brings the complicated security problem to the grid system implementation. At present, there is not an integrated solution to satisfy these security demands. In this paper, the existing core foundation technology of grid security is firstly presented, and the important significance of security for grid computation is brought forward. Then the security demand under grid environment is analyzed, and the grid system framework based on trust evaluation.As the most important part in trust mechanism, the trust model emphasizes on the credibility of members and data. Though notifying and limiting the improper behaviors in grid, trust model guarantees the use of network more reasonable for users. The trust model not only can encourage good behaviors in network, but also can accelerate well development of the system.The existing trust model based on trust domain designs the trust relation of nodes in grid, but it doesn't give the detailed and general analysis to the following questions: It is not considered that nodes trust is whether a relation of service providing quality or a relation of resource-consuming; The transaction context is not considered yet; The independent trust of nodes is not fully incarnated and each transaction must be strictly in accordance with the sequence of decision of trust; The weight of reference trust is not given; The impact that trust value changing as time attenuation is not considered. Based on the existing research, this paper gives an improving study aiming at the trust model based on trust domain. In the new model, each node saves the trust value of node that is higher than the trust threshold of itself, and the trust data of all nodes in this domain are saved by intra-domain agent. The inter-domain agent is responsible for maintaining the intra-domain agents. The intra-domain agents under the same inter-domain agent are trustable to each other. The new model divides the relation of trust into the service providing quality relation and resource-consuming relation, and brings in some amend-factors to improve accuracy of computing trust value. This paper introduces the basic idea and structure of the model framework, defines the role level for entity of security service level, and discusses several topics that the method of calculating,...