Patient Medical Records: Implementation of a Security Solution Based on the Hyperledger Fabric Blockchain

In this paper, we have developed a solution for securing patient medical records based on blockchain. In our approach, we first carried out a comparative study of different blockchains. This comparative study, based on the Ethereum, Corda and Hyperledger Fabric blockchains, enabled us to select Hyperledger Fabric as the development framework for our blockchain. The criteria justifying our choice are essentially: the modularity of the architecture, the variety of programming languages for smarts contracts, the possibility of creating private channels between members of a network, high access control and data confidentiality, and a flexible consensus model. These criteria are crucial as they guarantee both the robustness and flexibility of the network in a shared medical record context. The proposed solution is a decentralized application that exchanges data in a consortium-type blockchain network, with three different organizations in a healthcare pathway: a hospital, a pharmacy and a laboratory. Other organizations can be added to the network taking into account the need to share and secure healthcare information. Our solution uses the IPFS (Interplanetary File System) protocol for distributed document storage, increasing data security and availability. To facilitate exchanges between network nodes, particular emphasis was also placed on the choice of consensus algorithm. First we chose the Solo Orderer algorithm, which uses a single Ordering Service node to process transactions and add them to blocks, and then we used the Kafka orderer algorithm, which offers high scalability and robust resilience in production environments. The choice of these two consensus algorithms enabled us to set up and deploy a blockchain network that stores and secures sensitive data from medical analyses or examinations in a patient's care pathway.