The Analysis And Improvement Of A New ID-based Proxy Blind Digital Signature

With the rapid development of computer internet technology and communication technology, the degree of society informatization is increasingly high. The fields of political, military, diplomatic, commercial, financial, especially the electronic commerce, electronic checks, electronic shopping, electronic publishing and the protection of intellectual property rights are closely related to information security.Information security is related to national security, social stability and the well-being of the people. The relationship of information security and the military, diplomatic, political, economic, financial, especially the daily life of people is increasingly close, and the importance of information security is growing with day.So far, the cryptography technology has become a core technology to solve the problem of information security. Not only is it used for traditional fields for data encryption and intrusion behavior against the enemy, but also is used for the authentication of digital information and the security of product for individual and enterprise that are related to information security.The digital signature,one of the core technology of the many application fields of the information security, has gradually replaced the traditional handwritten signatures that are based on written documents, and it has extensive uses in the fields of e-government, e-commerce trade, bank financial system, the network orders ticket system, e-mail, electronic publishing and the protection of intellectual property rights.In the actual work and life, ordinary digital signature has been unable to meet the various special needs, so the digital signatures with a variety of special properties are emerging, for example, the proxy digital signature, a special digital signature that has the basic function of digital signature and the proxy function of digital signature, what’s more, there is another one example, the blind digital signature, a digital signature with special property that can make the signed message a secret to the signer and the signer cannot track for the information content so that to ensure the safety of the signed message. Proxy digital signature and blind digital signature have played a decisive role in electronic commerce and electronic voting.Proxy blind digital signature gathers the advantages of the above two digital signatures, and it has the important application value in the modern information society, and it gains the attention of cryptography field as soon as it is put forward. Proxy blind digital signature has the both properties of proxy digital signature and blind digital signature, that is to say, the proxy signer not only can accept the authorization of original signer to complete the digital signature, but also the proxy signer can make the digital signature when he doesn’t know the signed message, so that to ensure the concealment of the signed message.By analyzing the security risks of a new ID-based proxy blind digital signature, this paper puts forward a safer and more efficient proxy blind digital signature based on certificateless public key cryptosystem. Compared with the original scheme, there exist no problems of the management of public key certification and the key escrow, so the safety of the scheme has been greatly improved.