A Hybrid Trust Model for Enhancing Security in Distributed Systems

We propose a hybrid trust model for enhancing security in distributed applications by combining the "hard" and "soft" trust relationships. The motivation is to compensate for the drawbacks associated with individual hard trust and soft trust models. We develop a formal hybrid trust model for specifying the hybrid trust relationships and associated operations. The new model provides a flexible way for specifying the security relevant trust requirements which compensate the drawbacks of the individual trust models while preserving their advantages. We provide application guidelines on how the hybrid trust relationships can be applied to achieve mutual improvements between the individual models