Research And Design Of Proxy Blind Signature Scheme

The popularization of computer network has brought great convenience topeople’s daily life, and takes us into an informational society. With the developmentof computer network technology, the information security problems have becomeincreasingly prominent. The technology of digital signature ensures the authenticityof information transmission. However, the general signature, which is a simplesimulation of handwritten signature, can not meet the practical need any more, underthe various application backgrounds, many digital signature schemes with specialproperties have emerged, and proxy blind signature is a typical one. As thecombination of proxy signature and blind signature, proxy blind signature plays animportant role in electronic commerce.In this thesis, proxy blind signature schemes are analyzed and studied, the mainresults are described as follows.Firstly, a kind of identity-based proxy blind signature scheme is analyzed, and itis found that the scheme can’t satisfy the unlinkability property. The proxy signercould make a linkage between a message signature and the corresponding blindmessage signature. An improved identity-based proxy blind signature scheme isproposed, which can resolve the security problems existing in the original scheme,and retains the merits of the original scheme. It has some application value.Secondly, combining proxy blind signature with certificateless signature scheme,a certificateless proxy blind signature scheme is proposed. This scheme can overcomethe problem of the certificate management in the certificate-based public keycryptosystem and the inherent key escrow problem in the identity-based public keycryptosystem, being able to prevent forging signatures by un-trusted key managementagencies. A security analysis of the scheme is given, the following analysis show thatthis scheme not only has all the properties of proxy blind signature, but also with abetter performance.Thirdly, a proxy blind signature scheme with designated message recoveryreceiver was constructed. The designated receiver can recover messages from signature directly, enabling a reduction of system’s communication and animprovement in the communication efficiency. The results of safety analysis showedthat the scheme possessed higher security feature and gained a certain practical valueconsequently.At the end of this paper, we summarize the whole of the thesis and theprospective developing of proxy blind signature scheme in the future.