Type-2 Fuzzy Trust Aggregation

Trust is a fundamental concept that is critical in human decision processes in almost all domains, but of particular relevance in the domain of computer security. In many computer systems deployed today, trust is only modeled indirectly through a serious of formal rules and regulations describing when privileges are to be granted or revoked. Recently, research has been conducted into the area of fuzzy trust modeling in order to allow a more intelligent tradeoff analysis by the computer security software. In this paper, we extend this work to support Type-2 fuzzy reasoning. The Type-2 input membership functions can be derived from multiple human experts’ judgments. This allows us to incorporate the inherent imprecision in trust judgments in a mathematically principled manner. Keywords— Computer security, fuzzy systems, trust modeling, Type-2 fuzzy logic.