Securing Blockchain-Based E-Voting Through Shamir's Secret Sharing over Ethereum

Smart contracts are one of the main drivers of advances in blockchain technology and its applications, like e-voting. This study proposes the integration of Shamir's Secret Sharing (SSS) algorithm into blockchain-based electronic voting (e-voting) systems powered by smart contracts to enhance voter privacy without compromising integrity. We developed a prototype on Ethereum using Remix IDE and validated the design over a test network using test accounts. We evaluated this integration based on cost, complexity, privacy, and accessibility metrics. We examined existing privacy-enhancing solutions and focused on their application within e-voting systems. Our analysis considers gas fees on Ethereum as well as the computational and data storage overheads caused by SSS. Although the current implementation of secret sharing falls short of preserving privacy (due to inherent transparency of smart contracts), it shows that it can successfully obfuscate the candidate selection of voters. Accessibility is measured through the time required for system access and vote casting. Overall, our results indicate that while integrating SSS increases cost and system complexity, it holds significant potential for enhancing privacy in e-voting systems.