Research On Medical Data Security Sharing Model Based On Blockchain

With the rapid development of medical digitalization,the demand for medical data sharing is increasing.Safe and efficient medical data sharing is of great significance to improve the efficiency of disease treatment and the level of public health.However,there are still some problems in the field of medical data sharing.First,there are data barriers between different medical institutions,which makes it difficult to achieve cross system data sharing.Secondly,data leakage is easy to occur in the process of data sharing,which affects the enthusiasm of data owners.Many medical institutions use cloud servers to share and store medical data,but cloud data is easy to be tampered with by cloud providers or attackers,causing patient privacy disclosure.Blockchain is a distributed database technology characterized by decentralization,tamper resistance,traceability,and data openness and transparency.The above advantages can be used to break the barriers to medical data sharing and solve the problems of data tampering and disclosure.Therefore,this paper uses blockchain technology to study the safe sharing and efficient storage of medical data.The main research contents are as follows:(1)Study the security sharing model of medical data.Aiming at the problems of centralized storage,low sharing efficiency and privacy leakage of medical data,a security sharing model of medical data based on blockchain is proposed.The model uses verifiable random numbers to improve the primary node election strategy,and ensures the reliability of the primary node by random election.In addition,lightning network technology is used to establish offline anonymous transaction channels.Both sides of medical data sharing realize decentralized anonymous communication by attaching data blocks in semi committed transactions and performing mutual signature operations.At the same time,offline channels are used for data sharing,which can achieve rapid transactions while reducing the pressure on the main chain.Secondly,a complete medical data sharing process is designed,which is conducive to the standardization of medical data sharing.The security analysis shows that the model can resist man in the middle attack,replay attack and witch attack while ensuring data integrity.The scheme evaluation and performance analysis show that the model can realize the random selection of master nodes and support the safe sharing of medical data.(2)Study the consensus mechanism of medical data sharing alliance chain.Aiming at the problem of insufficient security and transaction delay of consensus mechanism used in medical data sharing alliance chain,an improved practical Byzantine faulttolerant consensus mechanism suitable for medical data sharing is proposed.The consensus mechanism introduces a random voting algorithm to select nodes,and classifies nodes according to the voting results,which improves the security of system nodes.Secondly,use verifiable delay function to resist hardware acceleration and fast verification to conduct distributed master node election,and use the hash value of the previous block and the user’s private key to generate a random hash value to increase the unpredictability of the master node and ensure consensus security.Finally,the consensus process is simplified into three stages to reduce the communication cost between system nodes and clients.The algorithm evaluation and experimental analysis show that the consensus mechanism has higher performance in security and sharing efficiency.