Proxy Blind Signature Analysis And An Improvement

Nowadays digital signature tecnology is more and more widely applied in many fields, so some special digital signature technology is needed under different situation.This passage do the research mostly in the proxy blind signature, people often need to give their digital signature power to the dependable proxy, permit the proxy exert the power. It includes the signature power. Sometimes in need of the keeping secret, the original signer don't want the proxy signer to know much about the secret of the company, so he need to use the proxy blind signature technology.We do the research from the basic digital signature technology, first we research in the proxy signature, and then we go deep into the proxy blind signature. We deeply research in the proxy blind signature based on the disperse logarithm. And put the disperse-logarithm-thinking into ECC; make the proxy signature scheme and the proxy blind scheme which based on the ECC.When we do the research on the proxy blind signature based on the disperse logarethm, we deeply analysis the Elgamal and the TAN's schemes, we point out that the TAN's schemes can't resist the fake attack, and put forward the improved measure. And we compared the improved schemes with the Elgamal scheme and the TAN's scheme. Pointed out that the Elgamal's scheme can't resist the fake attack, and don't satisfy the"can't trace"and it also can't resist the fake attack. The TAN's schemes satisfy the"can't trace", but it also can't resist the fake attack. The improved schemes not only satisfy the"can't trace", but also can resist the fake attack.This passage also applys the signature based on the disperse logarithm into the ECC, put forward the proxy signature scheme and the proxy blind signature scheme,and compare the basic scheme based on the ECC with which based on the RSA. We make the conclusion that the ECC schemes has the following advantage:strongest security character in one bit, the short secret key, the fast calculating speed, the short signature length, so it will suitable for the smartcard and it will replace RSA and became the proxy blind signature scheme's future.