Constructing Optimistic ID-Based Fair Exchange Protocols via Proxy Signature

Abstract

This paper introduces a natural paradigm for fair exchange protocols, called ID-based partial proxy signature scheme. A security model with precise and formal definitions is presented, and an efficient and provably secure partial proxy signature scheme is proposed. This is a full ID-based optimistic fair exchange protocol. Unlike the vast majority of previously proposed protocols, this approach does not use any zero knowledge proofs, and thus avoids most of the costly computations.