Cryptology ePrint Archive: Report 2018/1100

Correction to "Improving the DGK comparison protocol"

Thijs Veugen

Abstract: At the IEEE Workshop on Information Forensics and Security in 2012, Veugen introduced two ways of improving a well-known secure comparison protocol by Damgård, Geisler and Krøigaard, which uses additively homomorphic encryption. The first new protocol reduced the computational effort of one party by roughly $50\%$. The second one showed how to achieve perfect security towards one party without additional costs, whereas the original version with encrypted inputs only achieved statistical security. However, the second protocol contained a mistake, leading to incorrect outputs in some cases. We show how to correct this mistake, without increasing its computational complexity.

Category / Keywords: Cryptographic protocols / implementation, application

Date: received 13 Nov 2018, last revised 16 Nov 2018

Contact author: thijs veugen at tno nl

Available format(s): PDF | BibTeX Citation

Note: This is a correction of a previous paper.

Version: 20181116:132549 (All versions of this report)

Short URL: ia.cr/2018/1100


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