DBT-PDP: Provable data possession with outsourced data batch transfer based on blockchain

In the scenario of large-scale data ownership transactions, existing data integrity auditing schemes are faced with security risks from malicious third-party auditors and are inefficient in both calculation and communication, which greatly affects their practicability. This paper proposes a data integrity audit scheme based on blockchain where data ownership can be traded in batches. A data tag structure which supports data ownership batch transaction is adopted in our scheme. The update process of data tag does not involve the unique information of each data, so that any user can complete ownership transactions of multiple data in a single transaction through a single transaction auxiliary information. At the same time, smart contract is introduced into our scheme to perform data integrity audit belongs to third-party auditors, therefore our scheme can free from potential security risks of malicious third-party auditors. Safety analysis shows that our scheme is proved to be safe under the stochastic prediction model and k-CEIDH hypothesis. Compared with similar schemes, the experiment shows that communication overhead and computing time of data ownership transaction in our scheme is lower. Meanwhile, the communication overhead and computing time of our scheme is similar to that of similar schemes in data integrity audit.