A Privacy-Preserving Voting Protocol on Blockchain

As blockchain technologies mature and ecosystems over blockchain evolve, peers on blockchain networks often face situations in which they need to conduct voting for decision-making; as happened in the case of the DAO hard fork event on Ethereum. However, a natively built-in voting mechanism is not available on any of the existing blockchain platforms. Thus, the decision making either is delegated to a few network members who make such decisions offline or is dependent on third party online voting services. In both cases, peers directly or indirectly rely on trusted parties or centralized systems. This is against the basic decentralization principle of blockchain and exposes the election to frauds. To facilitate decision-making in a decentralized and secure manner, we propose a native blockchain voting protocol for peers to vote over their existing blockchain network without the need of any trusted or third party. Our protocol preserves end-to-end privacy and possesses desirable properties such as detectability and correctability against cheating. A reference implementation of our protocol on Hyperledger Fabric that demonstrates the validity and practical applicability of our protocol is also provided.