Research On Proxy Signature Schemes

Digital signatures, one of the most important components of cryptography, are the theoretical basis of protecting the integrity and authenticity of information. With the development of the internet, special kinds of digital signatures, which are based on different applications, have been used widely and deeply in practice. As a new kind of singing technology, proxy signature has been applied to the electronic paying system, mobile agent system, electronic voting, electronic auction, electronic commerce and the security of the internet. In the paper, the theory of proxy digital signature and an electronic voting Scheme are studied. The main results are the following:1. The overview of the study of proxy digital signature is presented. Based on bilinear pairings, signing schemes which include proxy signatures, proxy blind signatures, and threshold proxy signatures are analyzed.2. A new proxy signature scheme based on bilinear pairing is proposed, which is unforgeable under CDHP assumption and has strong security.3. An anonymous voting scheme for self-organized group without trusted third party is put forward. The scheme allows participants to anonymously vote on some issue and to securely compute the result of the vote without any interaction among participants. Furthermore, the scheme is convenient to be converted into an anonymous threshold signature.