SCS: A Secure Cloud Storage Framework with Enhanced Integrity and Auditability Using Consortium Blockchain System

Abstract

The widespread use of cloud storage enables users to access their resources remotely via a self-service model. Utilizing pay-per-use storage services provided by cloud service providers (CSPs) requires users to commit financially to their resources. This paper introduces an SCS framework that provides a secure architecture for cloud storage using a consortium blockchain network to solve the trust issue. This framework substitutes the third-party auditor with peers of a consortium blockchain network, which handles the role of data storage and verification. The storage space is segmented between uncommitted and committed storage, where uncommitted storage is designated for storing unverified documents. In contrast, committed storage is designated for the storage of committed documents. Those data documents that have undergone consensus validation by a specified threshold of peer nodes will be transferred to committed storage. The implementation of the SCS framework is carried out on Hyperledger Fabric. The security analysis proves that SCS effectively safeguards cloud storage against devastating attacks while preserving its integrity and auditability. The performance analysis reveals that the metrics for document upload time, document retrieval time, block acceptance time, execution time, and latency are optimal compared to state-of-the-art techniques.