Study On Group Signature Schemes And Their Applications In E-commerce

This paper presented some research results in group signature schemes and their applications in e-commerce. Firstly, this paper introduces the research background, significance and the actuality of research about group signature scheme. Secondly, we described the fundamental concepts and properties of group signature scheme and some general digital signatures that can be used to construct group signature amply, and presented a group signature scheme based on the integer factorization. Thirdly, we explained the fundamental concepts and properties of authorized group signature in detail and propounded a secure authorized group signature based upon the discrete logarithm. Finally, we illuminated electronic payment system in e-commerce and designed a simple and high secure electronic cash system with multiple banks based on group signature.The main contributions of this paper are:1. The general method used to construct group signature and a new group signature scheme based on Guillou-Quisquater signature scheme were presented. The scheme is designed simply,the length of group signature won't increase as group member increases and can revoke effectively any group member.2. Based on the idea of authorized group signature, a modification of the scheme presented by SHI Rong-Hua was made, and a secure authorized group signature scheme is presented,which satisfies the fundamental secure properties, and besides, enhances the validity of signature for the length of group signature won't increase as group member increases.3. A simple and high secure electronic cash system with multiple banks was presented, which has overcome the limitation of existing electronic cash system scheme. It satisfies the fundamental secure properties of the electronic cash system with multiple banks, and besides, the realization process of the scheme is easier than e-cash protocol based on the blind group signature. Furthermore,we add some information of the user's consumption into the scheme to enhance the security of protocol, which can make user's issuing bank supervise some doubtful business.