Data Security Protection in Cloud Computing by using Encryption

Cloud computing is a paradigm for offer information technology services on the internet, such as hardware, software, networking and also the storage can be accessed anywhere at any time on a pay-per-use basis. however, storing private data onto servers of the cloud is a challenging matter. therefore, cryptography technique and authentication are used in this model to ensure confidentiality and proper access control of sensitive data. therefore, in this paper i proposed a model to protect data in cloud computing. in this model the algorithm of the rivest- shamir- adleman (rsa) is applied to the private data. furthermore, the protocol of challenge-handshake -authentication-protocol (chap) is used to improve the security of the authentication as well. the results show this model is secure and practical.