International Journal on Computer Science and Technology (IJCST)
The cloud servers managed by cloud providers are not completely trusted by users while the data files stored in the cloud may be responsive and confidential such as business plans. To preserve data privacy a basic solution is to encrypt data files and then upload the encrypted data into the cloud. Regrettably conniving a capable and secure data sharing scheme for groups in the cloud is not an effortless task due to the following challenging issues. Sharing data in a multi owner manner while preserving data and characteristics privacy from an untrusted cloud is often a challenging issue due to the frequent change of the membership.