Abstract: With the rapid development of Internet technology, the data of the userís information have raised up largely, so internet storage became more and more important in todayís life. The intelligence and networking development of the electronic products, meeting the needs of the public users or the businesses for portable and high capacity has become the most important in development of the information industry. Cloud storage has become the preferred option to provide portable storage service for ordinary users, solve the requirement of large capacity, the difficulty of management and the requirement of high generic extensions. The security mechanism of cloud storage system is also becoming more and more important. By using AES encryption algorithm the security mechanism of usersí files uploading and downloading has been researched. So in this paper a new algorithm is introduced, regarding the extent of Cloud network, the most important feature of the proposed algorithm is its resistivity against the attacks. The algorithm is designed and implemented in java script in CloudSim environment. The objective of this paper is the development and creation of a new algorithm by implication of some changes in the initial key of AES encryption algorithm.

Keywords: Security, Data security, Cloud computing security, Cryptography, AES Encryption Algorithm, CloudSim.