Biometric authentication offers enhanced usability for digital payments, but traditional centralized architectures suffer from single points of failure. While blockchain integration promises decentralized trust, existing solutions often store biometric helper data (e.g., fuzzy commitments) directly on-chain. We demonstrate that such transparency, even in permissioned settings, exposes low-entropy biometric inputs to offline brute-force attacks and identity-linkage risks if the immutable ledger is accessed by malicious nodes. To resolve this transparency–privacy paradox, we propose a threshold-based decentralized authentication framework. Unlike prior works, our protocol keeps all sensitive Biometric-Enhanced Key Derivation (BEKD) tokens entirely off-chain, using the blockchain solely for freshness enforcement. We provide a game-based security analysis of brute-force resistance, unforgeability, and unlinkability. Our experimental results demonstrate that our scheme’s gas cost is acceptable, offering a robust solution for self-sovereign biometric identity.
Hui Cui, Haoze Cheng, James Boorman· Pragmatic Cybersecurity· 0 citations
For national statistics offices (NSOs), data sharing is essential for the production of official statistics, yet it must comply with stringent confidentiality and governance mandates. Blockchain technology has emerged as a promising means to enable trusted and auditable data exchange under these constraints, motivating a growing body of research across public-sector domains. This paper presents an up-to-date survey of blockchain-based data-sharing solutions in government and NSO contexts, reviewing studies published between 2018 and 2026. Given the limited research specific to official statistics, this survey evaluates public-sector solutions with particular attention to their alignment with NSOs’ strict privacy and data governance requirements. Departing from prior reviews that primarily organise the literature by technical architectures or application domains, the survey adopts the Five Safes framework as a unifying analytical lens. Through this governance-focused synthesis, the survey identifies recurring architectural patterns and design principles that support secure and accountable data sharing, including permissioned or consortium blockchains, hybrid on/off-chain storage, selective integration of privacy-enhancing technologies, and smart contracts to automate governance functions such as access control and workflow management. Building on these insights, the paper outlines two distinct reference architectures that distil best practices from existing studies for blockchain-enabled data sharing under public-sector constraints, and highlights open challenges—most notably scalability and integration with legacy systems—pointing to future research directions towards solutions that combine strong security assurances with practical governance compliance.
I. Sandyawan, Fatih Sigmanova, Zoey Ziyi Li et al.· Mathematics· 0 citations