A Machine Checkable Logic of Knowledge for Specifying Security Properties of Electronic Commerce Protocols

A number of researchers have proposed various tools for checking security protocols. Most of these tools work by comparing the set of possible traces (as expressed by some model of computation) to the set of correct traces (often expressed as a set of relationships between events in a trace). In this paper we propose a new logic of knowledge in which one can express relationships between events, variables, and knowledge. This logic has a precise semantics with respect to a well deened model of computation and can be checked automatically. In addition, the fact that we can express properties about knowledge allows us to express security properties speciic to electronic commerce, including anonymity.