Non-repudiation Protocols And Their Logic Verification

Electronic commerce on the internet has been one of main activities in contemporary economic life. But E-commerce is based on the internet which has little security. Participants of electronic exchanges can not trust each other. Moreover, their interests and goals are different. For gaining more advantages, they often repudiate what they have done in exchanges. Now, repudiation has become one of the major threats in E-commerce. In order to solve this problem, the internet has to provide non-repudiation service based on non-repudiation protocols. So well-designed non-repudiation protocols will promote the further development of the electronic commerce.This paper mainly introduces non-repudiation protocols from following aspects: background, the current research situation and logic verification method. It also summarizes the basic concepts, classification, properties and formal analysis tools associated with non-repudiation protocols. It analyzes the security weaknesses and the security requirements of several typical non-repudiation protocols. It emphasizes formal analysis of Zhon-Gollmann non-repudiation. It discusses the design of optimistic non-repudiation protocols. In the end, the paper dabbles in fair exchange protocols which are expansions of non-repudiation protocols.The main contributions are as follows:(1) Currently used non-repudiation protocols always involve a trusted third party or semi-trusted Third party. But supposing TTP is ideal to be realized in E-commerce, it is difficult to find a Semi- trusted TTP in some environments. In addition, the TTP can be easily attacked by hackers. If it is spoiled, the communication will collapse, In response to these problems, based on a generalized secrets sharing scheme, a non-repudiation protocol with many third parties is proposed in this paper. It distributes one third party s task to many third parties and reduces the possibility of the third party to be attacked in current protocols. Meanwhile it does not demand high reliability from these third parties, but conformation to the attack model proposed in the paper. Thus, such third parties are easily available.(2)Based on a digital signature with message recovery, we present a new fair non-repudiation protocol with features of security, efficiency and economical use of net...