No abstract

In the past, most medical data were created and managed by hospitals. These days, however, patientscan generate these data by themselves without visiting hospitals. Unlike previous data, the latter isgenerated by patients themselves. To efficiently manage these data without need of the third party,a blockchain-based access control was proposed. If the patient wants to delegate the right of theaccess to his data, he creates a token for the requester and stores it on the blockchain as a form of thetransaction. Moreover, patients can make it invalid and impossible to re-use at any time. However,if the number of the transactions in the blockchain network is exceeded the maximum throughput ofthe system, the system cannot provide a reliable service. Moreover, due to the feature of the publicblockchain, anyone can see the history of the specific data by tracing the transaction stored on theblockchain. In this paper, to solve the scalability problem on the public blockchain based accesscontrol system and its invasion of privacy, we propose a token based personal data management systembased on . When the requester sending a request message, the resource owner creates a tokentransaction for the intermediary’s address and then asks the delivery of the transaction between hisprimary chain and the requester’s sub chain via multiple sub chain. Finally, the relayed transactionfor the access control is stored on the requester’s blockchain. The linkability of transactions on thedifferent blockchain is hidden from the third party user and our system is able to process it veryquickly regardless of the blockchain’s throughput.