Design And Analysis Of Designated Verifier Signature

Along with the development of computer science and internet, especially great spread and application of electronic commerce and E-government, the problem of information security gradually draws much more attentions. Digital signature, its emergence fulfills the actual demands and the advancement of information security, is an information technology which could guarantee messages against any damage in transmitting procedure and settle disputes between the two sides of communication. Since its emergence, based on different mathematic problem, lots of digital signature schemes have been proposed, for instance, RSA signature scheme is based on the problem of integer factorization, ElGamal signature scheme is based on the problem of discrete logarithms. In order to satisfy the actual application requirements of digital signature in transmission network, plenty of other different signature schemes have been presented, for example, proxy signature and blind signature. Designated verifier signature come out as well in this condition, which plays an increasingly important role in privacy protection and online designated authorization.In other ordinary digital signature scheme, anyone could verify the validity of a signature. However, in a designated verifier signature scheme except the designated verifier, nobody could verify the validity of the signature, thus it effectively protects signer's privacy. In this paper, based on achievements made by others, some beneficial trial and exploration in designated verifier signature have been made out. The following are the main research results:1. Study and analyze a digital signature scheme, and discover that the scheme is easy to suffer the replay attack when applied in other network environment, thus propose a highly effective scheme with more widespread application.2. Combining proxy signature with designated verifier signature, a new designated verifier proxy signature scheme is proposed.3. Make some analysis on an improved ID-based designated verifier proxy signature scheme and figure out a security loophole in it, then prove that the security attack is valid.4. A certificateless strong designated verifier signature scheme is presented, which alleviates the key escrow problem of ID-based cryptography and certificate authorities in traditional public key cryptography.