A Privacy Protection Mechanism for NoSql Database Based on Data Chunks

In SaaS (Software as a Service) applications, the tenants upload their data into the databases of the cloud service provider. Because the data is not directly managed by the tenants, the security of the private information can't be guaranteed. In order to protect tenants' private information, a mechanism based on data chunks is put forward. It can protect tenants' privacy in the clear text. It divides tenants' data into several parts that we called data chunks. However, it is put forward for relational databases. Therefore, this paper proposes a new mechanism for NoSql databases to store the tenants' data by data chunks. In order to improve the efficiency of data reconstruction after storage based on data chunks, an optimization strategy based on memory cache is proposed. It divides the cache into two parts. One is used to store the frequently used data. The other one is used to store the data that is used by next operations. The experimental results prove that this mechanism has availability and feasibility.