Research On Data Sharing Technology Of Medical Internet Of Things Based On Blockchain

With the development of Internet of things,sensors and other technologies,the data collection range of medical Internet of things devices is wider and the number is larger,which promotes the vigorous development of intelligent medicine,personalized medicine and other fields.Users can realize remote diagnosis of diseases by sharing the health data collected by wearable Internet of things devices,so that users can know their physical condition in time.However,these health data contain sensitive information of users such as blood pressure and heartbeat.Once leaked or maliciously spread,it will bring a lot of inconvenience to users’ personal life.Therefore,it is very important to realize the safe and flexible sharing of health data in the field of intelligent medicine and personalized medicine,and avoid the problem of privacy disclosure in the sharing process.Aiming at the current difficulties and inflexibility of health data sharing and the privacy leakage caused by the transparency of the blockchain,this thesis proposes a blockchain-based medical Internet of Things data sharing scheme to achieve safe and flexible sharing of health data,and also solves the problem of privacy leakage due to the transparency of the blockchain.First,this thesis proposes a key management strategy based on key spanning tree.Users use the key stream generated by the key spanning tree to encrypt the health data stream generated by the Internet of Things device,and share the health data through the corresponding token in the shared key spanning tree according to their own needs.In order to find the token that needs to be shared in the key spanning tree,this thesis designs a token search strategy based on the key spanning tree,which is used to locate the token.Secondly,in order to avoid the leakage of private information such as users’ personal health status and doctor-patient relationship caused by the transparency of the blockchain,this thesis proposes an effective protocol based on the Elgamal encryption mechanism to blind the identities of authorized doctors on the blockchain.Malicious attackers cannot find out the past diagnosis transactions made by the authorized doctor through the blinded identification,cannot establish the doctor-patient relationship between the user and the authorized doctor,cannot infer the areas that the authorized doctor is good at,and cannot know the user’s physical health,thus avoiding the leakage of private information such as the user’s personal health and doctor-patient relationship.In addition,in order to reduce the time spent on verifying the signature information in the blockchain transactions one by one,this thesis uses the batch signature verification scheme based on BLS to batch verify the signature information on the blockchain.Finally,the security analysis and experimental verification of the scheme proposed in this thesis are carried out.The results show that the scheme proposed in this thesis can realize the safe and flexible sharing of health data,and also solve the privacy leakage problem caused by the transparency of the blockchain.In addition,this thesis uses the batch signature verification scheme based on BLS to reduce the time overhead of verifying signature information in blockchain transactions one by one,so that smart medical services can better serve human beings.