Degree Name

Master of Science (Hons.)


School of Information Technology and Computer Science


Electronic Payment Systems that deal with daily shopping and payment over the Internet are one of the most important concerns of today's electronic commerce. There is a large body of research in this field, and in particular, on electronic cash (e-cash) systems. In e-cash systems, protecting customer's privacy has received much attention and many challenging problems relating to the trade-off between multi-party security and system efficiency are proposed. This thesis gives a brief survey of e-cash systems. We investigate various problems raised in building secure and efficient e-cash systems. This includes efficient off-line e-cash, perfect anonymity, revocable anonymity, combining the advantages of on-line and off-line approaches and wallet loss recovery.