SmartphoneDemocracy: Privacy-Preserving E-Voting on Decentralized Infrastructure using Novel European Identity

2025-07-12

AI Summary

Existing electronic voting systems suffer from overreliance on centralized authorities, strong trust assumptions, and insufficient privacy guarantees. To address these issues, this paper proposes a smartphone-based decentralized end-to-end verifiable voting scheme. The approach integrates the European Digital Identity Wallet (EUDI Wallet) for Sybil-resistant identity authentication, employs zero-knowledge proofs to ensure voter anonymity and ballot correctness, and leverages the serverless TrustChain blockchain for decentralized ledger maintenance and public verifiability. This work is the first to synergistically combine these three components within a mobile voting framework, substantially reducing dependence on trusted third parties. Prototype evaluation demonstrates acceptable computational and communication overhead in medium- to large-scale elections. Furthermore, formal security analysis under a rigorous threat model confirms the scheme’s robustness and practical deployability.

Technology Category

• Humans and AI: Voting
• Data Mining & Knowledge Management: Representing, Reasoning, and Using Provenance, Trust
• Machine Learning: Privacy

Application Category

• Security and Privacy: Privacy-enhancing technologies
• Responsible Web: Data and user privacy-enhancing technologies for the Web
• Systems and Infrastructure for Web, Mobile and WoT: Decentralized Web and Fediverse systems

Abstract

The digitization of democratic processes promises greater accessibility but presents challenges in terms of security, privacy, and verifiability. Existing electronic voting systems often rely on centralized architectures, creating single points of failure and forcing too much trust in authorities, which contradicts democratic principles. This research addresses the challenge of creating a secure, private e-voting system with minimized trust dependencies designed for the most versatile personal device: the smartphone. We introduce SmartphoneDemocracy, a novel e-voting protocol that combines three key technologies: the emerging European Digital Identity (EUDI) Wallet for Sybil-resistant identity verification, Zero-Knowledge Proofs for privacy-preserving validation, and a peer-to-peer blockchain (TrustChain) for a resilient, serverless public bulletin board. Our protocol enables voters to register and cast ballots anonymously and verifiably directly from their smartphones. We provide a detailed protocol design, a security analysis against a defined threat model, and a performance evaluation demonstrating that the computational and network overhead is feasible for medium- to large-scale elections. By developing and prototyping this system, we demonstrate a viable path to empower citizens with a trustworthy, accessible, and user-controlled digital voting experience.

Problem

• Secure private e-voting with minimized trust dependencies
• Decentralized smartphone-based voting using EUDI and blockchain
• Ensuring verifiable anonymous voting via Zero-Knowledge Proofs

Innovation

• European Digital Identity for Sybil-resistant verification
• Zero-Knowledge Proofs for privacy-preserving validation
• Peer-to-peer blockchain for serverless bulletin board