Reputation-based Trust Model in Grid Security System

The security problem is a hot topic in grid research due to the dynamics and uncertainty of grid system. There are three entities defined as users, applications and resources in grid environment. In such situation, users are vulnerable to risk because of potential incomplete or distorted information provided by malicious resources, and as grid system grows tremendously in size, the possibility of users to attack the network by providing aggressive or vicious applications will increase greatly. Trust management is an effective method to maintain the credibility of the system and keep honesty of entities. This paper presents a trust model, which is used to compute and compare the trustworthiness of entities in the same autonomous and different domains. This model provides different methods to deal with the problems of users and related resources belonging to the same or different domains. Furthermore, a simulation experiment is provided to evaluate the trust model, and the simulation result shows it is effective to resolve the security problems in grid environment.