under the control of secret key and keeping information secure. The first major event in this history was the definition of the concept of public-key cryptography. What we call public key cryptography was the major issue which was presented in 1976. According to the history of cryptography, Diffie Hellman and Merkle Have become famous as cryptographers who explored the concept of public-key cryptography, while Rivest, Shamir and Adleman developing the new kind of public key cryptography as RSA, the
strategies: hide the existence of the information, or make the information unintelligible. Cryptography is the art and science of keeping information secure from unintended audiences, of encrypting it. Conversely, cryptanalysis is the art and science of breaking encoded data. The branch of mathematics encompassing both cryptography and cryptanalysis is cryptology. Modern cryptography uses sophisticated mathematical equations (algorithms) and secret keys to encrypt and decrypt data.
Based Access Control and Attribute Based Access Control, security to the data stored in cloud is enhanced through the fine grained access control policies. Attribute Based and Role Based Encryption techniques are used as the main encryption primitive. Signature Based authentication is used to improve security. Fine grained access control is provided with authentication