Efficient Multiplicative Homomorphic E-Voting

Multiplicative homomorphic e-voting is proposed by Peng et al to overcome some drawbacks of the traditional additive homomorphic e-voting. However, its improvement is limited and it inherits the efficiency bottleneck of additive homomorphic e-voting, costly vote validity check. Moreover, it has a new drawback: grouping the votes and revealing which vote is from which group compromises or at least weakens privacy. In this paper, the two drawbacks of multiplicative homomorphic e-voting are overcome. Firstly, an efficient vote validity check mechanism is designed to remove the efficiency bottleneck of homomorphic e-voting. Secondly, a group shuffling mechanism is designed to shuffle groups of votes and achieve complete privacy. With the two new mechanisms, the new multiplicative homomorphic e-voting scheme is efficient and secure.