Between Trust and Secrecy: Decentralized Reputation with Privacy Assurance via Self-Sovereign Digital Identities

• Antonio Mateus de Sousa UFBA
• Allan Edgard S. Freitas IFBA
• Leobino N. Sampaio UFBA

DOI: https://doi.org/10.5753/sbseg.2025.11475

Abstract

While authentication and authorization ensure identity and access control, they do not guarantee essential attributes such as service quality and reliability over time. In this context, reputation serves as a crucial complementary mechanism, reflecting factors like availability, data integrity, and compliance with SLAs. However, centralized approaches reduce system resilience and compromise user sovereignty. The proposed architecture adopts a decentralized model based on Decentralized Digital Identities (DDIs) and blockchain technologies, enabling verifiable and privacy-preserving proof of reputation. The PoC demonstrated that the system effectively penalizes malicious behavior, enhancing the security and robustness of the environment.

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