International Journal For Innovative Engineering and Management Research

As more users move their data to the cloud, ensuring data integrity has become a significant concern.Blockchain technology, with its decentralized and immutable nature, has emerged as a promising solution, replacing the need for third-party auditors.This paper introduces a data integrity system built on blockchain expansion technology, aiming to address the high costs associated with blockchain network maintenance and the creation of new blocks, which often arise as the size of the blockchain grows in data integrity audit schemes.The proposed system involves both users and cloud service providers (CSPs) deploying smart contracts on the main chain and sub-chains.By offloading intensive and frequent computing tasks to the sub-chain, the system reduces the load on the main chain.Results from the sub-chain are periodically submitted to the main chain, ensuring the integrity and finality of the data without compromising performance.To enhance the user experience, the concept of non-interactive auditing is introduced, eliminating the need for constant communication between the user and the CSP during the audit process.A reward pool mechanism is also incorporated to promote data security.Through comprehensive analysis in areas such as storage, batch auditing, and data consistency, the effectiveness of the scheme is demonstrated.Experiments conducted on the Ethereum blockchain platform show that the proposed system significantly reduces storage and computational overhead, proving its practical viability.