Fair Exchange Protocol

With the explosive development of Internet and information technology,e-commerce has been a major platform for modern economic activities. It is gettingmore and more attentions of countries, governments and companies, and it leads tothe requirement of more security and fairness in business. Thus it is urgent topropose a new fair e-payment protocol which is the basis of e-commerce.In this thesis, we first introduce fundamental knowledge and security ofe-commerce and fair exchange, and discuss the important principles of designingfair exchange protocol in detail. And then introduce certificateless signature andanalyze the security model of certificageless signature deeply. We propose a newe-payment protocol for e-check. This protocol based on certificateless concurrentsignature which makes the purchase and payment of digital products have come intoeffect concurrently, applied to the trade of digital products in network environment.Finally, we analyze and research certified mail protocols that proposed by ASW andJianying Zhou respectively, point out some flaws in these two protocols andimprove Jianying Zhou’s scheme.