Public auditing system: Improved remote data possession checking protocol for secure cloud storage

Cloud storage is a one of the services of cloud computing. The data owners move their data from local systems to the cloud servers provided by cloud service providers. By this, users get high quality and on-demand data storage services and user is free from the maintenance load. Beside all these benefits, there are several matters about cloud storage security. Most of the cloud service providers are not completely trustworthy. The actual concern of the cloud users is whether the information stored on cloud is intact. Therefore, it is of great importance for users to know whether their data is kept intact or not, in this paper Improved Remote Data Possession Checking protocol based on homomorphic hash algorithm is proposed. This proposed system supports secure and efficient dynamic operations at block level. Dynamic opreation includes insert, delete, update, and modify. To find the location of each data Merkle Hash Tree is used. A third party auditor can also be called as trusted party auditor checks the user's data stored in cloud storage for its correctness and accuracy. A third party ensures correctness of user's data. Many times verification is allowed without the requiring the verifier to compare against the original data. They incur less computation and communication cost. Enhanced security and performance analysis shows that the proposed scheme is more efficient and strong against replace attack launched by malicious server.