CareBlocks: A Blockchain-based Health Information Sharing Framework for Medical IoT

Blockchain is a continually growing immutable ledger used for bookkeeping all the data recorded over the network in chronological order. In the healthcare sector, the power of blockchain can be harnessed to eliminate the use of a centralized hospital database or cloud to store health data. Since data storage in the third-party systems leads to the loss of the user’s control over their health data and may lead to privacy leakage, we propose CareBlocks, a secure health information sharing framework for medical Internet of Things environments using blockchain. The framework constitutes five layers: data layer, network layer, incentive layer, consensus layer, and application layer, when ordered from the bottom to the top. In CareBlocks, the access to the users’ data is limited only to the user itself, and this is achieved by encrypting the health data, and the data is also protected with fine-grained access control. The users have the authority to decide which doctors can have access to their health-related data, and this preference can be modified anytime by the user. Since it is critical to ensure privacy and high availability to the patient’s records, the IPFS platform has been leveraged to store the patient data where these records are encrypted using secret-key cryptography. The proposed architecture is composed of four sub-blockchains that interact among themselves to provide the desired usability. PatientChain plays the role of storing all the medical records in one place, and DoctorChain similarly stores the diagnosis in an encrypted format. ChemistChain and InsuranceChain allow the patients to make the payment and claim of funds limited only to a few clicks and reduce paperwork. The use of blockchain to store health data also makes the system tamper-resistant, thereby avoiding medical disputes. With PlusCoin, a cryptocurrency unit, CareBlocks enables users to pay their fees to the doctor and the chemist. The proposed blockchain-based framework allows smooth interactions among healthcare entities without losing the integrity and privacy requirements.