## Cryptology ePrint Archive: Report 2008/181

Proofs of Knowledge with Several Challenge Values

Grzegorz Stachowiak

Abstract: In this paper we consider the problem of increasing the number of possible challenge values from 2 to $s$ in various zero-knowledge cut and choose protocols. First we discuss doing this for graph isomorphism protocol. Then we show how increasing this number improves efficiency of protocols for double discrete logarithm and $e$-th root of discrete logarithm which are potentially very useful tools for constructing complex cryptographic protocols. The practical improvement given by our paper is 2-4 times in terms of both time complexity and transcript size.

Category / Keywords: cryptographic protocols /

Date: received 18 Apr 2008, last revised 1 Jun 2008

Contact author: gst at cs uni wroc pl

Available format(s): PDF | BibTeX Citation

Short URL: ia.cr/2008/181

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