End-to-End Verifiable Blockchain Voting Architecture Integrating Decentralized Identity and Threshold Decryption Protocols

Abstract

Secure electronic voting has become a critical requirement for digital governance because conventional paper, electronic, and internet voting systems expose elections to opaque counting, centralized control, and weak independent verification. Blockchain, smart contracts, and privacy-preserving cryptography provide a technical basis for tamper-resistant electoral records and auditable tallying. Existing blockchain voting approaches still insufficiently couple voter anonymity, eligibility verification, scalable transaction processing, and verifiable encrypted tallying within a complete operational architecture. The objective of this work is to develop and evaluate BBSTVS, a secure and transparent blockchain-based voting system for privacy-preserving electronic elections. The system was implemented on the Polygon zkEVM Layer 2 test network using Solidity smart contracts, W3C decentralized identifiers, ElGamal homomorphic encryption, zk-SNARK eligibility proofs, nullifier-based double-vote prevention, and threshold decryption. A simulated election with 100,000 voters was executed to quantify transaction latency, confirmation time, fraud rejection, tally duration, and receipt verification. Vote casting required 1.2 s on average, transaction confirmation occurred within 2 s, and the complete encrypted tally finished in under 8 s. No fraudulent vote was accepted, and every accepted ballot was linked to a verifiable receipt. The architecture supports public auditability while preserving ballot secrecy. Future research should address post-quantum migration, offline participation, and larger multi-region deployment.