  The rapid expansion of user medical records across global systems presents
not only opportunities but also new challenges in maintaining effective
application models that ensure user privacy, controllability, and the ability
to commercialize patient medical records. Moreover, the proliferation of data
analysis models in healthcare institutions necessitates the decentralization
and restorability of medical record data. It is imperative that user medical
data collected from these systems can be easily analyzed and utilized even
years after collection, without the risk of data loss due to numerous factors.
Additionally, medical information must be authorized by the data owner,
granting patients the right to accept or decline data usage requests from
medical research agencies. In response, we propose an innovative solution for
implementing a decentralized system utilizing an EVM-compatible blockchain and
IPFS for decentralized storage. To ensure privacy and control, we employ Proxy
Re-Encryption (PRE), a cryptographic authorized method, within the medical data
marketplace. Our proposed architecture significantly reduces costs associated
with granting read access to healthcare research agencies by minimizing the
encryption and decryption time of stored records. Furthermore, it empowers
users with enhanced control over their health data through tamperproof
blockchain smart contracts and IPFS, safeguarding the integrity and privacy of
their medical records.
