Computer Engineering and Applications Journal

New scheme of fair exchange of digital signatures

Yu Shang

Published Jan 1, 2008• 1 citation

Abstract

Based on the verifiably encrypted signature scheme without random oracles recently proposed by Gorantla et al.,a new scheme of optimistic fair exchange of digital signatures is proposed in this paper.The two players firstly exchange their verifiably encrypted signature on agreed-upon messages then their ordinary signature after the verification of each other's verifiably encrypted signature.If one of them executes the protocol dishonestly,the other can resort to a trusted third party so as to get the purpose of fair exchange of signatures.The proposed scheme has properties of short signature,low computation and verification cost.It can realize exchange of digital signatures fairly and efficiently.

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