A Blockchain-Based Framework for Enhancing Data Integrity and Privacy Protection in Cloud Storage Networks

Abstract

Cloud storage networks have become the default infrastructure for retaining sensitive digital records, yet their reliance on centralized providers exposes data to silent tampering, unauthorized disclosure, and single points of failure. This paper presents a blockchain-based framework that jointly enhances data integrity and privacy protection in cloud storage networks, using healthcare records as the motivating application. The framework is organized into three layers: an access layer through which patients and providers interact with a client application, a control layer in which a permissioned consortium blockchain of five institutions governs four dedicated chaincodes (EHRChain, DiagnosisChain, PolicyChain, and LogChain), and a storage layer built on the InterPlanetary File System (IPFS). Encrypted records are stored off-chain, while only their SHA-256-derived content identifiers and ownership proofs, represented as non-fungible tokens (NFTs), are anchored on-chain....