As a solution to this, we suggest evaluating voting schemes in the universal composability framework. We investigate the popular class of voting schemes based on homomorphic threshold encryption. It turns out that schemes in this class realize an ideal voting functionality that takes the votes as input and outputs the result. This ideal functionality corresponds closely to the well-known ballot box model used today in manual voting. Security properties such as privacy, accuracy and robustness now follow as easy corollaries. We note that some security requirements, for instance incoercibility, are not addressed by our solution.
Security holds in the random oracle model against a non-adaptive adversary. We show with a concrete example that the schemes are not secure against adaptive adversaries. We proceed to sketch how to make them secure against adaptive adversaries in the erasure model with virtually no loss of efficiency. We also sketch how to achieve security against adaptive adversaries in the erasure-free model.Category / Keywords: Voting, homomorphic threshold encryption, universal composability. Publication Info: ACNS 2004, this is a slightly extended version Date: received 4 Jan 2002, last revised 6 Apr 2004 Contact author: jg at brics dk Available formats: Postscript (PS) | Compressed Postscript (PS.GZ) | PDF | BibTeX Citation Note: Major revision. The obsolete version can be found as BRICS tech report RS-01-52 (www.brics.dk). Version: 20040406:120013 (All versions of this report) Discussion forum: Show discussion | Start new discussion