A mutual non-repudiation protocol with privacy

Abstract

Non-repudiation services provide the parties involved in a transaction with protection against the other party by denying that a particular event or action took place. They collect irrefutable evidence to support the resolution of any such disagreement. We address this security issue by first examining the previous work done in this area, and then propose a novel protocol to achieve mutual non-repudiation service, encompassing both mandatory evidence of origin and mandatory evidence of receipt. By using two simple ideas, a conditional signature and a public notice board, the novel protocol can achieve this security service in a simple but effective manner. By applying cryptography technology, this protocol also provides privacy for the parties using the security service.