A survey on blockchain-based integrity auditing for cloud data

With the rapid advancement of cloud computing, cloud storage services have developed rapidly. One issue that has attracted particular attention in such remote storage services is that cloud storage servers are not enough to reliably save and maintain data, which greatly affects users' confidence in purchasing and consuming cloud storage services. Traditional data integrity auditing techniques for cloud data storage are centralized, which faces huge security risks due to single-point-of-failure and vulnerabilities of central auditing servers. Blockchain technology offers a new approach to this problem. Many researchers have endeavored to employ the blockchain for data integrity auditing. Based on the search of relevant papers, we found that existing literature lacks a thorough survey of blockchain-based integrity auditing for cloud data. In this paper, we make an in-depth survey on cloud data integrity auditing based on blockchain. Firstly, we cover essential basic knowledge of integrity auditing for cloud data and blockchain techniques. Then, we propose a series of requirements for evaluating existing Blockchain-based Data Integrity Auditing (BDIA) schemes. Furthermore, we provide a comprehensive review of existing BDIA schemes and evaluate them based on our proposed criteria. Finally, according to our completed review and analysis, we explore some open issues and suggest research directions worthy of further efforts in the future.