Research On Theory And Application Of Blind Signature

With the development of computer and communication technology, the information industry expands rapidly, the frequency and scale of information communication are all present a growth trend, The digital and information way of life gradually become the normal mode. On the one hand, the construction of information network brought great convenience to our work and daily life; on the other hand, it brought great threat to the ubiquity information. Due to the digital signature could ensure the security of information effectively, more and more attention has been paid to it.With the continuous development of the era and realistic demand, as a special type of digital signature technology, blind signature technology is proposed. In blind signature system, Signer allows the message owner blinding the message firstly and then he signs the blinded message, at last, message owner ublinding the signature, so as to get the signature of the original message. Since it was proposed, blind signature technology has developed more than30years. Blind signature technology is analyzed, improvement and supplement continually by many researchers. To meet the demand of reality, blind signature scheme is combined with other signature scheme, and the new signature scheme is proposed; for it could protect the content of the files, the blind signature is more and more widely applied in electronic commerce and electronic government affairs; but there are still some problems to study in the structure of the scheme and the application in the specific agreement.In this paper, we mainly study the blind signature. Firstly, we introduced the research background, the research status, the security features and the general construction method of blind signature, analysis the existing blind signature scheme; then we proposed the improved identity based blind signature scheme and the improved certificateless blind signature scheme for special application. In this paper, we mainly do the following work:First, we studied the identity-based blind signature scheme, according to the existed blind parameter signature scheme and the realistic demand, we proposed an anonymous signature scheme with identity. In this scheme, key generation center (KGC) transforms the users’ real identity to be blind variable, and users transform blind variable to be his anonymous identity; User could login in the system and manage the group with his anonymous identity, and signed the related information with his real identity. Group members and KGC could validate the signatures and obtain the identity information of the signer, but he can’t get anonymous identity of the signer. The signer could submit his evidence to KGC to prove that his real identity while dispute appeared.Second, we proposed an improved certificateless proxy blind signature on basis of the existing certificateless blind signature scheme. The scheme has characteristics of certificateless signature scheme and proxy blind signature scheme, it could satisfies the security requirements of certificateless proxy blind signature scheme, and has higher efficiency compared with the existed scheme.Third, we introduce the basic characteristics and the model of electronic voting, and design an anonymous electronic voting protocol based on the proxy blind signature scheme, this protocol could achieve the basic functions of electronic voting.