BLOCKCHAIN-BASED SECURE DATA SHARING FRAMEWORK FOR CLOUD COMPUTING

Abstract

The rapid growth of cloud computing has enabled flexible data storage and sharing; however, it also introduces significant challenges related to security, privacy, and access control. This paper proposes a blockchain-based secure data sharing framework to address the limitations of traditional cloud architectures. The proposed framework integrates distributed ledger technology with smart contracts to enable automated and transparent authentication and access control mechanisms. Data are stored off-chain, while metadata and access permissions are recorded on the blockchain to ensure integrity and traceability. Mathematical models are developed to evaluate the probability of valid access and the effectiveness of the access control mechanism. Analytical results demonstrate that the proposed approach significantly enhances security, mitigates single point of failure risks, and improves resistance against common attacks. Although the use of blockchain introduces additional latency due to consensus mechanisms, the system maintains high scalability. This study provides an effective and practical solution for secure data sharing in distributed cloud environments.