Self-Sovereign Digital Identity System for Smart Cities: A Pilot Project with Trustchain and Hyperledger Indy in the Municipality of Santa Rosa

• Carla O. Castanho Unijuí / URI
• Marcelo P. Chequin Unijuí
• Sandro Sawicki Unijuí
• Rafael Z. Frantz Unijuí https://orcid.org/0000-0003-3740-7560

DOI: https://doi.org/10.5753/cblockchain.2026.23616

Abstract

In a smart city context increasingly dependent on big tech platforms, this paper presents the implementation and validation of a system integrating Trustchain and Hyperledger Indy for decentralised citizen identification in accessing environmental data in Santa Rosa (RS), Brazil, addressing the need to mitigate centralised data vulnerability while preserving privacy and self-sovereignty. Through a mobile application that requires verifiable credentials, the proposed solution demonstrates the feasibility of the hybrid architecture, consistent performance in digital identity creation and verification metrics, and a stable registration and query workflow, positioning itself as an effective identity management mechanism for smart cities.

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