A Privacy Protection Method Based on Key Encapsulation Mechanism in Medical Blockchain

At present, many blockchain technologies have played a role in the storage and sharing of medical data, functions such as on-chain operation and data encryption have not been fully realized in terms of privacy protection. To solve these problems, this paper proposes a medical privacy protection method based on key encapsulation mechanism (KEM) in blockchain. First, the medical data of the patient is symmetrically encrypted, and then the public key of the symmetric cipher is asymmetrically encrypted. Furthermore, the public key of the asymmetric cipher and the encapsulated symmetric key are stored in the smart contract of the blockchain, so as to achieve the purpose of privacy security protection and on-chain operation. Through the experiment of security and throughput, the decentralized medical privacy protection method combined with KEM can realize the security protection of medical data, which has good throughput performance, and good resistance effect in the face of block forgery attack.