University of Calcutta
Cloud storage has recently attracted a substantial amount of attention from both industry and academia. Notable commercial cloud storage services include Amazon S3, Google Drive, Dropbox, Microsoft Skydrive, and Apple's iCloud. Compared with traditional storage systems, cloud storage offers several desirable advantages, including high data availability, high data reliability, and dynamic storage space. To provide highly available and reliable storage service, Cloud Storage Providers (CSPs) make tremendous investments in storage hardware and network bandwidth. To be profitable, CSPs need to recover these costs from reasonable charges to cloud users.