Abstract : Data storage over cloud is a demanding service but it is vulnerable for various attacks. It is required to provide strong security to this data. An authenticity of the data on remote storage is necessary but data owners have to trust on cloud storage for their outsourced data. There is a need of some mechanism to check correctness of the data without compromising its confidentiality. We have studied homomorphic algorithms so that can be applied on the cipher text. Aim of the framework designed here is to enable any authentic user or auditor to verify hash value generated by owner with the hash value of encrypted data which is stored at remote storage for assuring authentication of the data. This can be done with strong mathematical cryptographic algorithms those can be used in the public environment and can provide better performance complexity.