Research On Shared Data Access Control Based On Blockchain

Due to the rapid growth of data information,the era of big data has arrived,and data sharing among various departments and organizations has become an important way of information exchange.A good data interaction method can provide users with convenient data sharing and ensure the security of the access process.In practical applications,data access can be performed directly between different organizations,and cloud servers can also be used for storage and sharing.These methods improve the efficiency of retrieval and expand the storage space to a certain extent,but there are hidden dangers in the security of the access process.The centralized management method cannot effectively resist the risk of external attacks,which may lead to the valuable shared data being fully disclosed.Therefore,how to protect the confidentiality of data,resist various security risks and reduce the risk of privacy leakage are the primary considerations in the process of sharing data.This paper studies the data access control model from three aspects: decentralization,user credit and attribute encryption.main tasks as follows:Aiming at the current problem that user rights cannot be dynamically changed over time and security problems in access control contracts,an access control model based on role-based access control model and based on blockchain and user credit is proposed.First,the role publishing organization distributes roles to relevant users,and stores the access control strategy in the blockchain through a smart contract.The contract sets an access credit threshold,and the contract information is verifiable by any service providing organization in the system,Traceable and not tamperable.Secondly,the model evaluates the final credit based on the user's current credit,historical credit and recommended credit,and obtains the access rights of the corresponding role according to the final credit.Finally,when the user's credit reaches the credit threshold set by the contract,the user can access the corresponding service organization.The experimental results show that the model has certain fine-grained,dynamic and security in security access control.In order to improve the security of shared data and reduce the computational overhead during the access process,an access control scheme based on blockchain and layered attribute encryption is proposed.The scheme includes a data owner,a data visitor,a trusted authorization center,Cloud service providers,proxy servers and smart contracts.This scheme can guarantee the security in data transmission,reduce the encryption and decryption overhead and storage consumption of the system,and can also reduce the user's decryption overhead through a proxy server.The verification analysis proves that it has certain feasibility and practicability.In short,the research of shared data access control based on blockchain proposed in this paper can provide a decentralized management method and a secure access control model for the shared data platform,which can not only improve the operating efficiency of the system,but also effectively solve Existing problems,and more practical.