Verifying Data Integrity in Amazon EC2 Cloud Storage by Privacy Preserving Third Party Audit

Cloud Storage is evolving as a very economical option for both home and professional users for storing their large amount of data remotely on Cloud Server. Cloud storage gives wide range of advantages like user is billed based on usage, user do not need to maintain data as the data is maintained by the cloud service provider, though the data is stored remotely it can be worked and used as if it is present locally and many more. These advantages make cloud storage very appealing still it is facing wide range of internal and external threats. The data loss incidents may take place because of network and software bugs, the CSP (Cloud Service Provider) may reclaim the data storage of rarely accessed or not accessed at all for monetary reasons or may hide the data loss incidents. So gain trust of users in cloud storage in this paper a secure cloud storage system with privacy preserving Third Party Auditing is proposed and implemented. The data is stored on Amazon EC2 instance from Amazon Web Services. The results are extended to do batch auditing for multiple data files.