| For its low cost,flexibility and not limited by time and space,cloud storage service has gradually become users’ first choice to store data.Meanwhile,data transaction is not accomplished through large-scale data transmission between users,but achieved by changing the ownership of data stored in the cloud server.Users lose direct control over this data with this convenience,so it is necessary to ensure the integrity of personal data stored in the cloud server and the security of ownership transaction.Data integrity audit scheme which supports data ownership transaction is the main technology to solve the above problems.Among them,data ownership transaction is completed by the cooperation between the two parties and the cloud server to update the data label.Data integrity audit is achieved through computing homomorphic labels.In order to reduce computing costs for users,third-party auditors(TPAs)are used to replace users join hands with cloud servers to complete data integrity audit tasks.The existing data integrity audit schemes that provide ownership transaction cannot support data ownership batch trading and tracking,both of which affect the practicability and security of this scheme.At the same time,all existing schemes require the participation of trusted TPAs,which leads to security risks brought by malicious or unstable TPAs.This paper focuses on the above issues,and the main results are as follows:(1)We design a scheme named as Provable Data Possession with Traceable Outsourced Data Transfer.The data labels adopted by the existing research schemes do not contain the transaction information of the data,so the owner cannot track all the past owner of a certain data.This results in the data purchased by users cannot be continuously traced to the source,and there are potential security risks of malicious data transfer.To solve this problem,data label which supports traceable ownership transactions by embedding the information of each data ownership transaction into data label,and a data integrity audit schemeTDT-PDP is proposed.Since data label contains all the ownership transaction information,the buyer can track the historical transaction process of this data,ensuring the security of the user’s purchase data,Safety analysis shows that TDT-PDP is proved to be safe under the kCEIDH hypothesis in the stochastic prediction model.Experimental results show that TDT-PDP has similar efficiency to similar schemes which have the function of data ownership transaction.(2)A scheme named as Provable Data Possession with Outsourced Data Batch Transfer is proposed.The data label updating calculation adopted by the existing schemes requires the proprietary information of data,so data owners cannot trade ownership of data in bulk that leads to low efficiency of data ownership transactions.To solve this problem,this paper proposes a data label structure that supports the function of data batch transaction,and designs a data integrity audit scheme where data ownership can be traded in batches--DBT-PDP.Since the data label updating calculation does not involve the proprietary information of data,the ownership of multiple data can be traded in batches,improving the efficiency of data ownership transaction.Safety analysis shows that DBTPDP is proved to be safe under the k-CEIDH hypothesis in the stochastic prediction model.Experiments show that the data ownership transaction efficiency of DBT-PDP is better than other schemes of the same type.(3)We design and implement the integrity audit prototype system of data ownership transaction based on blockchain.Existing blockchainbased data integrity audit schemes solve the threat posed by malicious or unstable third-party auditors(TPAs),but do not support data ownership transactions.In order to solve above the problem,this paper implements third-party auditors’ function of TDT-PDP and DBT-PDP with smart contract on blockchain,and further designs and proposes the integrity audit prototype system of data ownership transaction with these two schemes.The system which can guarantee security under the threat of malicious TPAs will support storage,audit,and ownership transaction functions of TDT-PDP and DBT-PDP. |
