BRA-PS: A Blockchain Reference Architecture for Public Sector Citizen-Centric Applications

Public sector organizations face growing pressure to modernize service delivery through digitalization while ensuring transparency, interoperability, and citizen trust. Although blockchain technology offers promising capabilities for addressing these challenges, the absence of clear architectural guidelines for public sector contexts limits effective adoption. This study proposes BRA-PS, a Blockchain Reference Architecture for Public Sector Citizen-Centric Applications, developed from a realworld digitalization project in Quebec, Canada. The architecture organizes components into six layers (presentation, business, communication, smart contract, blockchain, and data) with cross-cutting concerns addressing governance, access control, security, and monitoring. A key design principle is the publicprivate workflow separation, which enables inter-organizational collaboration while preserving each organization’s operational autonomy and data confidentiality. We validated the architecture through a case study involving a vehicle registration process between two public agencies, supported by a proof-of-concept implementation using Hyperledger Fabric. An Architecture Tradeoff Analysis Method (ATAM) evaluation, conducted with a panel of five domain experts, identified six architectural risks, including IPFS confidentiality exposure and smart contract inflexibility, six non-risks, six sensitivity points, and six trade-offs across three key quality attributes: autonomy, collaboration, and functional suitability. The results confirm that BRA-PS effectively guides implementation decisions and stakeholder alignment. Practical recommendations derived from the evaluation provide actionable guidance for blockchain adoption in public sector services.