The Right of Transparency for Citizens in the Context of GDPR Using Blockchain: A Proposed Architecture

Amid intense contemporary debates over the need for greater control over personal data, the Brazilian State legislates on the subject and gives rise to the General Data Protection Regulation (GDPR). Taking advantage of this debate to ensure transparency - a fundamental right provided in the Federal Constitution and regulated through the Access to Information Act (ATIA), we have investigated the use of blockchain to maintain traceability of queries carried out by public entities to citizens' data. More specifically, we propose a blockchain-based system platform for querying a citizen's data and storing the trace of queries in the blockchain. The generated history can then be consulted by the citizen, obtaining the name of the organization that carried out the search and what data was searched. To demonstrate the technical and operational feasibility of the proposal, we have implemented a web/blockchain-based system and carried out functional and performance tests, including overhead comparisons with the introduction of blockchain registration. The results were analysed and discussed in the work.