In cloud computing security, privacy and data confidentiality plays important role when popularity in terms of cloud computing services is consider. Till now there are various schemes, protocols and architecture for cloud computing privacy and data protection are proposed which are based on data confidentiality, cryptographic solution, cipher text blocks, various transforms, symmetric encryption schemes, attribute-based encryption, trust and reputation, access control, etc., but they are scattered and lacking uniformity without proper security logic. This paper systematically reviews as well as analyze research done in this relevant area. First various shortcomings in cloud computing, architectures, framework and schemes proposed for data confidentiality will be discussed; then existing cryptographic schemes, encryption functions, linear transform, grid storage system, key exposure, secret sharing, AONT (All or Nothing Transform), dispersed storage, trust, block encryption mechanism, attribute-based encryption, access control will be discussed; thirdly propose future direction with research challenges for data confidentiality in cloud computing; finally focus is on concern data confidentiality scheme to overcome the technical deficiency and existing schemes.