Proving Coercion-Resistance of Scantegrity II

By now, many voting protocols have been proposed that, among others, are designed to achieve coercion-resistance, i.e., resistance to vote buying and voter coercion. Scantegrity II is among the most prominent and successful such protocols in that it has been used in several elections. However, almost none of the modern voting protocols used in practice, including Scantegrity II, has undergone a rigorous cryptographic analysis. In this paper, we prove that Scantegrity II enjoys an optimal level of coercion-resistance, i.e., the same level of coercion-resistance as an ideal voting protocol (which merely reveals the outcome of the election), except for so-called forced abstention attacks. This result is obtained under the (necessary) assumption that the workstation used in the protocol is honest. Our analysis is based on a rigorous cryptographic definition of coercionresistance we recently proposed. We argue that this definition is in fact the only existing cryptographic definition of coe...

• Type: Journal
• Year: 2010
• Where: ICICS
• Authors: Ralf Küsters, Tomasz Truderung, Andreas Vogt
• Keywords: Communications, ICICS 2010, Rigorous Cryptographic Analysis, Scantegrity II, Voting Protocols