Abstract: The data management and ownership separation in cloud storage systems lead to the difficulties of data security and privacy protection. The traditional cloud storage data privacy protection mechanism based on simple encryption technologies brings larger extra overhead in the actual process of data manipulation. In order to achieve low overhead of the data privacy protection mechanism for cloud storage systems, this paper proposed a novel data privacy protection mechanism based on data partition and classification. The mechanism reasonably partitions the original data into two block; one is small, which is deployed locally, and the other one is large, which is deployed remotely, and then according to different security requirements of data, the data dyeing and data encryption technologies are adopted jointly in order to protect the cloud data privacy, improve flexibility and reduce overhead at the same time.

Key words: Cloud storage, Privacy protection, Data partition, Data classification