Research On Educational Resources Grid-Based Trust Mechanism

Construction of educational resources is important assurance to education information's rapid development, but following the number of educational resources increases dramatically. Education Resource Grid came into being in order to avoid coming into lonely information islands of educational resources,causing duplicate construction of educational resources and safeguard the overall sharing of educational resources, and the security problem is the important aspect in the research of Education Resource Grid.The study of Trust Model is in a long time, and has become a core element of the grid security. Trust mechanism can better response Grid's heterogeneity,dynamic,autonomous and so on, and solve the grid security risks more effectively than the traditional security mechanisms. Education Resource Grid is a special form of Grid, having Grid characteristics and the characteristics of its own. In this paper, Trust model is introduced into Education Resource Grid to construct Trust Model of Educational Resource Grid, combined the characteristics of Education Resource Grid, on the basis of improving grid trust model based on trust domain.This paper's main work as follows:(1)This paper researches several classical data grid model and Education Resource Grid. Based on hierarchy of educational resources in real world, this paper constructs multi-level Education Resource Grid based on domain, which adopts the tree structure, combines the level with domain, and is divided into multi-domain structure specifically, summing up the advantages of centralized storage and distributed storage.(2)This chapter presents a modified hierarchical trust model based on trust domains, which focuses the idea of three models, expands and improves the traditional trust model: based on subjective logic, trust domain, fuzzy logic trust model trust. Model is constructed in view of trust model based on domain, maintaining three trust interrelation table: Between-Domain Trust Table,In-Domain Trust Table,Between-Node Trust Table. The trust interrelation combines subjective logic and fuzzy logic, and is divided into direct trust interrelation and indirect trust inter- relation, therefore a new Education Resource Grid is made up. Education nodes in model belong to trust domain based on area, school campuses and branch libraries belong to headquarters, and trust domain nodes in the case of duplication are addressed in the traditional trust model based on trust domain. This model is set to a triple, the elements in the triple are collection of nodes or domain, judgment collection of trust interrelation, collection of model correction factor. The paper sets up model authentication mechanism, describing in detail node processing in Trust Model of Education Resource Grid.(3)This paper establishes the maintenance mechanism of trust value, constructs decay function and malicious node punishment mechanism, and introduces a large number of model correction factors to improve the performance of Trust Model of Educational Resource Grid. Formulas describe in detail trust value between nodes, domains, node-domain of model.Trust's calculation need considering a variety of factors: evaluation of the trust relationship, trust threshold, penalty factor, decay function, containing a node of the incentive mechanism; Indirect trust's calculation simplifies the recommended path, introducing trust factor to distinguish trust closeness and estrangement between recommended nodes and the demand node.(4)Simulation experiments express that this model shows better performance in attacking against malicious nodes, compared with the traditional educational resources grid model without the trust mechanism. The assessment of trust value in this paper has more stable accuracy. This model can improve effectively transaction success rate of EG.