Blockchain Integration in Data Space Architectures: the NOUS Project

The exponential growth of data and the emergence of federated digital ecosystems have made data spaces a cornerstone of the European Data Strategy. While these environments enable interoperability and sovereignty, they still rely on implicit trust among autonomous participants. This thesis investigates how blockchain technology can complement governance in data spaces by introducing verifiable mechanisms for integrity, traceability, and accountability. Within the context of the EU NOUS Project, the thesis proposes a blockchain-enabled architecture for data lifecycle management in federated data spaces. The proposed Proof of Concept (PoC) integrates blockchain notarization into the operational workflow of a data space, ensuring that each operation is traceable and immutable. The approach is validated through a top-down methodology, moving from architectural design to practical implementation that combines the data space middleware, EBSI-based blockchain layer, and the MASA use case. The results demonstrate that integrating blockchain strengthens the transparency and trustworthiness of federated data ecosystems. This framework takes shape within Europe's ongoing advancement toward trusted and interoperable data sharing, contributing to the vision of sovereign, accountable, and verifiable digital infrastructures.