Abstract: This system proposed an improve data security protection mechanism for cloud using two components. In this system sender sends an encrypted message to a receiver with the help of cloud system. The sender requires to know identity of receiver but no need of other information such as certificate or public key. To decrypt the cipher text, receiver needs two parts. The first thing is a unique personal security device or some hardware device connected to the computer system. Second one is private key or secrete key stored in the computer. Without having these two things cipher text never decrypted. The important thing is the security device lost or stolen, then cipher text cannot be decrypted and hardware device is revoked or cancelled to decrypt cipher text.

Keywords: cloud storage system, cloud security, cloud protection, two-factor data security protection.