A Secure and Decentralized Architecture for Medical Data Management in IoMT Using Blockchain and IPFS.

Abstract

In this thesis, we propose a practical and secure architecture for managing medical data in the context of the Internet of Medical Things (IoMT), leveraging blockchain technology, smart contracts, and digital signatures to ensure data integrity, traceability, and non-repudiation. The system allows medical records to be signed by doctors using their digital wallets and stored in a tamper-proof way via IPFS. A smart contract registers the hash and content identifier (CID) of each medical file on the blockchain. To address concerns related to data privacy and access control, the system integrates Lit Proto- col to encrypt files before uploading them to IPFS, allowing only authorized parties to decrypt and view the data under specific conditions. As a real-world application, we present a case study involving Algerian social security institutions (CASNOS and CNAS), demonstrating how our solution can prevent fraud and manipulation of medical records—particularly in sensitive scenarios such as recruitment processes in national companies. By ensuring that every medical file is verifiable, unalterable, and accessible only to authorized entities, this work contributes to building a transparent, secure, and decentralized healthcare ecosystem that empowers both institutions and individuals while safeguarding medical data.