Simulation-based analysis of E2E voting systems

Abstract

End-to-end auditable voting systems are expected to guarantee very interesting, and often sophisticated security properties, including correctness, privacy, fairness, receipt-freeness, ... However, for many well-known protocols, these properties have never been analyzed in a systematic way. In this paper, we investigate the use of techniques from the simulation-based security tradition for the analysis of these protocols, through a case-study on the ThreeBallot protocol. Our analysis shows that the ThreeBallot protocol fails to emulate some natural voting functionality, reflecting the lack of election fairness guarantee from this protocol. Guided by the reasons that make our security proof fail, we propose a simple variant of the ThreeBallot protocol and show that this variant emulates our functionality. © Springer-Verlag Berlin Heidelberg 2007.