In this paper we propose a highly efficient SDVS scheme based on pseudorandom functions, which is proved to be secure in the standard model. Compared with the most efficient SDVS scheme secure in the random oracle model, our scheme has almost the same complexity in terms of both the computational cost of generating a signature and signature size. A signature of our scheme is simply the output of a pseudorandom function. The security of the scheme is tightly reduced to the hardness of DDH problem and the security of the pseudorandom function.
Since our scheme is vulnerable to delegatability attacks, the study of which was initiated by Lipmaa, Wang and Bao in ICALP 2005, we then propose another construction of SDVS, which is the \emph{first} one immune to delegatability attacks. The scheme is also very efficient, and has the same signature size with that of Lipmaa-Wang-Bao non-delegatable DVS scheme. We show that it is secure based on discrete logarithm assumption and gap Diffie-Hellman assumption in the random oracle model.
Category / Keywords: public-key cryptography / strong designated verifier signature, non-delegatability, non-transferability, random oracles, standard model, signature scheme Date: received 23 Oct 2009 Contact author: csqhuang at student cityu edu hk Available formats: PDF | BibTeX Citation Version: 20091026:110712 (All versions of this report) Discussion forum: Show discussion | Start new discussion