Modern technical move ahead have given increase to the recognition and accomplishment of cloud. This novel standard is ahead an increasing awareness, since it gives cost proficient designs that sustain the communication, storage space, and exhaustive computing of data. On the other hand, these shows potential storage space examines bring many difficult design concerns; significantly due to the failure of data organize. These confronts, explicitly data privacy and data reliability, have major control on the safety measures and concerts of the cloud structure. Some threat representations take for granted that the cloud service provider cannot be believed, and consequently security exclusives suggest a high level protection declaration, such as storing encrypted data in cloud servers. Additional assume that cloud providers can be confidences, and that probable threats come mainly from external attackers and additional malicious cloud users.
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Public key, Cloud Computing, Public Key Encryption, Attacks, Data Sharing.