Abstract
Cloud computing (CC) is a distributed and centralized network of interconnected and interrelated systems that has emerged as an area of incredible impact, potential, and growth in the IT domain. In the last few years, this paradigm has thrived to become the fastest evolutionary segment for business and various industries. Despite the many advantages provided by the cloud, serious challenges related to privacy and security have arisen such as privacy exposure, data loss, manipulation, service-level agreement (SLA) violation, and concerns over the service and deployment models. In this article, a blockchain-based hybrid algorithm is proposed to tackle the privacy inefficiency of existing tools. A novel hybrid technique is used to encrypt data ahead of outsourcing it to data centers, and a unique digital signature is generated at clients and stored on a decentralized set of blocks. A virtual cloud similar to actual cloud service infrastructure was built to test the proposed framework. Despite the additional computational powers needed to run the proposed framework due to blockchain integration, the results show that data integrity and reliability are preserved and user's privacy is increased. Our results are discussed and benchmarked against the standard privacy tests standards such as changes in the stored data, the negligible overheads on cloud performance, and the data records of the blockchain structure.