Designated Verifier Proxy Signature Scheme Without Bilinear Pairing

Digital signature has become an indispensable security measure of information transmission in information security field recently. A valid digital signature can ensure integrity and reliability of the data, and also you can authenticate the signer’s identity. Proxy signature,a kind of digital signature,occurs when the signer can not sign a message personally due to travel or some other reasons and will pass his right of signing to other people. In recent years, with the flourishing of the e-commerce,the proxy signature is more widely used, such as electronic cash,distributed shared systems, electronic bidding and so on.In the ordinary proxy signature, anyone including the original and the proxy signer can verify the validity of the proxy signature. However, as to the sensitive information,the original signer just hope that only the authorized user can verify the validity of the signature. For example,digital receipt of e-book belongs to this type of signature.Considering the above scenario, the research on designated verifier proxy signature is very necessary.We analyze the current schemes of the designated verifier proxy signature and point out some of the following questions.First,the existing designated verifier proxy signature schemes have been mainly based on traditional public key infrastructure or identity-based public key cryptography, so the key escrow problem and certificate management issues can not be avoided.Second,although the concept of certificateless-based designated verifier proxy signature have been proposed, the bilinear pairing with high computational complexity are used in those schemes,which greatly reduces the efficiency of the program. Third,Statistically, there is no security proof in most of the relevant schemes,which can not guarantee the efficiency and safety of the schemes.In other words, no designated verifier proxy signature schemes could be both efficient and safe so far.For the above analysis,This paper introduces the basic knowledge of proxy signature,including elliptic curve discrete logarithm problem, provable security theory, random oracle model and designated verifier proxy signature. Secondly, I analyzed development situation of the designated verifier proxy signature, and compared the related schemes home and abroad longitudinally.And also,I compared the the complexity and performance of the existing relevant schemes longitudinally.At thesame time,we analyze the pros and cons of each scheme.Finally,in order to avoid those problems we found above, we put forward a new scheme,an efficient designated verifier proxy signature scheme in random oracle model. In the new scheme,we use elliptic curve multiplication to replace bilinear pairing operation, and adopt the method of certificateless-based proxy signature to solve the key escrow problem and certificate management issue.In order to prove the security of the scheme, we also set two games between challenger and attacker to simulate forging the signature.As a result,we construct a new proxy signature method and achieve an efficient and secure proxy signature.Compared with the existing programs, our program is better in computational complexity and performance, which makes the article more suitable for practical application.