Relationships Among e-Voting, e-Auction, e-Cheque, and e-Cash

This paper illustrates how a transformation technique can be used to demonstrate the relationship among e-voting, e-auction, e-cheque, and e-cash, even though they serve distinct purposes. Initially, we examine the definitions of e-cheque and e-cash schemes, along with their respective security models. Subsequently, we develop a systematic framework to transform e-cheque into e-cash, supported by formal proof demonstrating the security of the conversion. As a corollary, we further exemplify this integration with a generic transformation framework to obtain e-cash from e-voting directly by combining an existing transformation of e-voting into e-cheque and the transformation of e-cheque into e-cash which we established earlier. We apply our transformation framework to Li et al.’s transformed e-cheque scheme and Li et al.’s e-voting scheme to obtain a concrete, secure e-cash scheme that is IND-CCEA, IND-CIA, and EUF-CIA as an instance. Finally, we examine how our result contributes to the integration and relationship between e-voting, e-auction, e-cheque, and e-cash systems.