Practical strong designated verifier signature schemes based on double discrete logarithms

Abstract

We notice that a strong designated verifier signature (SDVS) scheme can easily be realized by any secure one-way and two-party authenticated key agreement scheme. So any SDVS scheme without lower communication/computation cost or enhanced security comparing to these one-way and two-party authenticated key agreement schemes may have less advantage in practical use. In this paper, we introduce an SDVS scheme which realizes low communication/computation cost and is more efficient than current one-way key agreement schemes and SDVS schemes. In addition, we show how to remove a hash function used in this scheme where in this modified scheme, an enhanced security will be provided such that the consistency of a signature cannot be ascertained by any third party even if the signer's private key is revealed. We will prove the security of our schemes using random oracle models. © Springer-Verlag Berlin Heidelberg 2005.