Subject Review: Cloud Computing Security Based on Cryptography

ABSTRACT The cloud computing providing to users and companies many services and facilities such as less cost, availability and risk management. The services of cloud computing are delivered in pay per usage way and on-demand and it can store huge amount of data. But the security concern is the main reason that makes companies afraid of using cloud computing and store their data on cloud servers. In this paper, we try to review and describe many encryption methods that used to protect data which stored in cloud computing and make a comparison among these methods.