Secure and dynamic public audit scheme based on blockchain and red-black tree

Longxia Huang, Xi Peng, Mengmeng Yang

Abstract: In the Cyber-Physical-Social System (CPSS), mobile service applications share and exchange data in the cyberspace and physical world. With the explosive growth of data, cloud storage service is introduced as it has broken through the limitations of local storage space. However, since cloud storage servers may remove some data to deceive users to save space, it is important to check the integrity of data in cloud storage servers. Most existing verification schemes support users to delegate a semi-trusted entity third-party auditor (TPA) to audit the stored data publicly, but it may result in user data security risks for its interests. The security risk is one aspect, what is worse, the high overhead of auditing also limits the the practicality of auditing. To tackle the issues, we put forward a secure dynamic public audit scheme based on blockchain and a red-black tree structure. Unlike relying on any single TPA, every user on the blockchain can act as an auditor to achieve public auditing. Secondly, based on the red-black tree, a new storage structure is proposed to store data signatures, which achieves efficient data storage and auditing. Based on the raised prototype system, we prove the security of our scheme and implement it on Hyperledger Fabric. Many experiments indicate that the scheme achieves the expected efficacy.