Blockchain-based certificateless public auditing with privacy-preserving for cloud-based cyber-physical systems

Cloud-server is an effective and flexible way to manage the massive amounts of data produced by cyber-physical systems. It is a better option to outsource these data to the cloud. When data is outsourced to the cloud, users lose control over it, compromising the data's integrity. Many public auditing schemes were proposed to address this issue, where trusted third-party auditors (TPAs) verify the integrity of data on behalf of the users. However, trusted TPAs are vulnerable and may not provide correct auditing results on time. Moreover, there is no trust nowadays. Blockchain-based auditing schemes were introduced to prevent trusted third parties from overcoming this issue. However, most blockchain-based public auditing schemes suffer from the key-escrow issue. To overcome the key-escrow problem and malicious auditors, in this article, a blockchain-based certificateless public auditing with privacy-preserving for cloud-based cyber-physical systems is constructed. The proposed scheme is secure against type I, II, III, and IV adversaries in the random oracle model. Further, the original proof of the data is masked using a random function to achieve data privacy when data is transferred between the cloud-server and verifier. The performance analysis shows that the proposed scheme has higher efficiency and is suitable for cyber-physical systems.