Research Of Ring Signature And Its Application In E-Cash

Currently, the rapid development of the computer technology and network communication brings people's work and life great changes. E-commerce, E-government and other information activities have become a core component of economic life. As a primary means of authentication in Information security technology, digital signature has been widely used. The first digital signature is only used in the electronic transmission of data to provide data authentication, integrity and non-repudiation. The basic digital signature does not always meet the different needs of practical applications, thus the special nature of the digital signature forms was generated in the context of specific applications, such as the blind signature, group signature and ring signatures.As a kind of simplified group signatures, ring signature overcomes the disadvantage that the right of the administrator in group signatures is too large, and the signer is unconditionally anonymous. Its spontaneous, unconditional anonymity and group characteristics has a special role in building E-commerce, E-government system. Therefore, the research for ring signature scheme has important theoretical and practical significance.Electronic payment system is a core component of E-commerce, its implementation and level of development has been the impact of E-commerce growth rate of the main factors. As an analog of traditional cash in the information space, with incomparable advantages than other E-commerce payments E-cash become the preferred technology in E-commerce online payment technology. The security and anonymity of E-cash are achieved by cryptography, the existing electronic cash protocols have been designed mostly based on blind signatures and group signatures. The ring signature with its good features is one important means in electronic cash protocol design. This paper focuses on how to construct ring signature scheme that can apply to electronic cash protocol.This paper has conducted the following works:1. Firstly, we have introduced the basis cryptography theory that associated with this article, ranging from basic number theory, mathematical difficulties and knowledge of digital signatures; then briefly summary of the ring signature and e-cash research and development status.2. Secondly, we introduce the basic principles and security features of ring signatures, analyze and summarize the method of ring signature scheme design; and also point out that a special digital signature technology is one of the key technologies of the E-cash applications. outlined several specific digital signatures and their application.3. Identity-based ring signature scheme is analyzed and an improved identity-based ring signature scheme is designed; we focus on the linkable ring signature scheme, and improve the identity-based ring signature, and propose a kind of traceability linkable ring signature scheme. The scheme is based on bilinear pairings. Compared with the traditional ring signature, it decreases the calculation of pairing consumption, and realizes the function of repetitive tracking. It is better meet the needs of the electronic cash applications.4. To ensure the special needs under the security of electronic cash, based on the existing ring signature and blind signature scheme, we design a safe and efficient electronic cash system. Compared to the previous electronic cash protocol, the protocol use better of ring signatures features to achieve double-spending behavior of pre-testing, and is able to track the signer's repeat identity information in the case of withdrawal of anonymity.