Data Security in Cloud Computing A Comprehensive Survey

Cloud Computing is evolving as incredible computing model which has been usually used for storing and retrieving large amounts of data over the Internet so data security is one of the major concerns with cloud computing. This paper describes the different techniques along with few security challenges, advantages and drawbacks. It also provides the analysis of data security issues and privacy protection affairs related to cloud by preventing data access from unauthorized users, managing sensitive data, providing accuracy and consistency of data stored. To deal with these security problems, this paper also proposes a novel data sharing mechanism that concurrently achieves data confidentiality and fine-grained access control on encrypted data and user revocation by combining ciphertext policy attribute-based encryption and proxy re-encryption. This paper also delivers security for cloud data storage through a proper key management system with multiple key managers using Shamir’s key sharing technique and the policy file encryption is done using Elgamal algorithm for secure data transmission.