A Secure Decentralized Trustless E-Voting System Based on Smart Contract

E-voting plays a significant role in social activities. The trust of the voting results and the privacy of each voter are always the most important concerns in designing secure e-voting system. In this paper, we design a decentralized trustless e-voting system based on the smart contract. To guarantee the correctness of the voting result, the smart contract on Blockchain is used to provide a trusted public bulletin board and trusted computing environment. To hide the identity of each voter as well as avoid multiple voting, linkable ring signature is used for each voter to group a signing ring. In addition, to make sure that all voters will see the voting result at the same time, or nobody can get it, threshold encryption without trusted third party is used to make secret-key secretly before tally stage. Moreover, the trust (power) of the voting system is separated to all voters. Even though some of them are malicious, the final result will not be influenced. The contract is deployed on the Ethereum private network. Some feasibility and cost analysis on money and time are also provided.