A Sharded Blockchain Architecture for Healthcare Data

The application of machine learning (ML) techniques to electronic health records (EHR) is gaining more and more attention as a method to extract valuable information that has the potential to enhance the decision-making process within the healthcare domain. A useful approach comes from the federated learning (FL) scenario, which facilitates the decentralised training of machine learning models using datasets that are stored locally, hence eliminating the necessity of data aggregation on a central server. Federated learning also ensures data privacy because the federated devices do not share the actual data and store it locally. It becomes a useful tool when integrated with blockchain technology, which provides some properties such as immutability and traceability that are useful to enhance the security of such applications. With the growing use of IoT healthcare (IoHT) devices, it is becoming challenging to manage them centrally and ensuring the healthcare data privacy. In this work, we propose an architecture to address the scalability issue related to the healthcare data management for federated learning networks with a sharding-based blockchain technique. We discuss some basic properties and report some results also coming from the implementation in Hyperledger Fabric.