E-Voting with Blockchain: An E-Voting Protocol with Decentralisation and Voter Privacy (1805.10258v2)

Abstract: Technology has positive impacts on many aspects of our social life. Designing a 24hour globally connected architecture enables ease of access to a variety of resources and services. Furthermore, technology like Internet has been a fertile ground for innovation and creativity. One of such disruptive innovation is blockchain -- a keystone of cryptocurrencies. The blockchain technology is presented as a game changer for many of the existing and emerging technologies/services. With its immutability property and decentralised architecture, it is taking centre stage in many services as an equalisation factor to the current parity between consumers and large corporations/governments. One of such potential applications of the blockchain is in e-voting schemes. The objective of such a scheme would be to provide a decentralised architecture to run and support a voting scheme that is open, fair and independently verifiable. In this paper, we propose potentially a new e-voting protocol that utilises the blockchain as a transparent ballot box. The protocol has been designed with adhering to the fundamental e-voting properties in mind as well as offering a degree of decentralisation and allowing for the voter to change/update their vote (within the permissible voting period). The paper highlights the pros and cons of using blockchain for such a proposal from practical point view in both development/deployment and usage contexts. Concluding the paper with a potential roadmap for blockchain technology to be able to support complex applications.

• The paper proposes a novel blockchain-based e-voting protocol designed to balance decentralization, transparency, and voter privacy, notably allowing voters to alter their ballots.
• The protocol employs four phases—initialization, preparation using a blinded token, voting with commitments and alterations, and counting—to ensure eligibility, privacy, fairness, and verifiability.
• Practical implementation faces significant challenges regarding blockchain scalability and smart contract costs, requiring future research and advancements for widespread adoption in electoral processes.

Overview of Blockchain-Based E-Voting Protocol

The paper under discussion presents an intricate examination of blockchain technology applied to electronic voting (e-voting), aiming to tackle issues related to decentralization and voter privacy. The authors propose a novel e-voting protocol leveraging blockchain as a transparent and immutable ballot box. This approach seeks to balance the core properties of e-voting, namely decentralization, transparency, and voter privacy, while also allowing for vote alterations within the permitted voting period.

Core Contributions

1. Protocol Design: The protocol integrates blockchain's inherent features, such as decentralization, immutability, and transparency, to enhance the integrity and verifiability of e-voting processes. Notable is the allowance for voters to change their votes within the election duration, which introduces a nuanced approach to voter coercion-resistance under the concept of "forgiveness."
2. Implementation Challenges: The paper explores the logistical and technological challenges of implementing such a protocol, especially concerning the current limitations of blockchain tech and smart contracts. It highlights issues concerning scalability, computational cost, and privacy safeguards necessary for practical deployment.

Methodology

The proposed protocol is structured into four sequential phases:

• Initialization Phase: Establishes the framework and system parameters for the election, including candidate listing and election timeline, captured in a genesis block.
• Preparation Phase: Voter eligibility is determined, and voters receive a blinded eligibility token signed by a central authority (CA). This token is crucial for maintaining voter anonymity and preventing the CA from linking voter identities to their votes.
• Voting Phase: Voters cast their initial ballots, which are cryptographically committed into the blockchain. Additionally, the protocol innovatively supports altering ballots, where voters can change their vote before the voting period ends.
• Counting Phase: Post-election, votes are unsealed and counted. This phase ensures transparency and allows verification by all blockchain participants.

Security and Verifiability

The protocol adheres to essential e-voting properties: eligibility, privacy, fairness, and verifiability.

• Eligibility is ensured by issuing a blinded eligibility token, preventing unauthorized votes.
• Privacy is safeguarded through cryptographic commitments and anonymous public keys, securing voter choices against identification.
• Fairness is maintained by delaying the ballot opening until the voting phase concludes, preventing undue influence.
• Verifiability is achieved by enabling every participant to audit the ledger's content, confirming the final tally's accuracy and authenticity.

Practical Implications and Future Directions

This research accentuates blockchain's potential in transforming voting systems by decentralizing traditional architectures, thereby fostering trust and widening participation. However, practical challenges, particularly concerning smart contract costs and blockchain scalability, are significant hurdles. Thus, future research should focus on refining blockchain's infrastructure to support complex applications like e-voting more efficiently. This involves developing blockchain networks capable of sustaining high transaction throughput and enhanced privacy protocols to ensure voter anonymity without compromising the system's verifiability.

In conclusion, while current blockchain technology possesses promising elements for e-voting, substantial advancements are essential for its widespread adoption in electoral processes. This paper provides a foundational framework for advancing such technological innovations, potentially steering the future path of democratic participation.