CASTTE: A Trust Management for Securing the Grid

It has been a fundamental but challenging problem to gain assurance of the trustworthiness of service providers or requesters and ensure their interests. We present the formal definition of trust management, and then propose a trust management, CASTTE, to secure sensitive services and requesters in grids. CASTTE verifies access trust by using trust negotiation so as to protect sensitive services, and protects sensitive information of the two negotiators effectively by using a negotiation strategy based on protection tree. Furthermore, we utilize trust force to specify provision trust and apply trust force to service selection. This paper implements CASTTE and designs experiments to evaluate its performance. The experimental results show that it can not only protect sensitive services at the cost of little performance of systems, but also identify good services from bad ones effectively.