Enhanced Blockchain Based Decentralized Public Auditing for Cloud Storage

Considering the development of cloud computing, customers' data may now be accessed remotely from any location via an online cloud server. Thanks to cloud services, users can experience the great ease of on-demand cloud apps, which don't take into account local infrastructure constraints. Since various users may be working together while accessing the data, data sharing becomes essential to achieving beneficial outcomes. In order to ensure that a user's private data cannot be read by unauthorized parties, the current PriCloud security solutions mostly concentrate on authentication. They overlook a small privacy issue, though, which occurs when a user asks the cloud server to look for ways to share data with other users. Additionally, there is PriCloud, which uses blockchain-based private payments and anonymous storage smart contracts to let customers pay their storage providers without giving up their privacy. Whether or not the challenged access request is successful in obtaining the necessary data access rights, it may nevertheless disclose the user's privacy. To address the aforementioned privacy issue for cloud storage, we propose in this work a Privacy-Preserving Authentication Protocol with Shared Authority (PPAPS). The matching method for anonymous access requests in the PP APS allows for shared access authority while taking security and privacy into account. The second stage guarantees a user can access just their own information fields by implementing attribute-based access control. Lastly, the cloud server uses proxy re-encryption to facilitate sharing of data between different users.