Secure Skyline Group Queries Based on Encrypted Dominance Graphs in Cloud Environments

In this paper, we define and investigate the secure skyline group query problem and propose a method named Secure Skyline Group Query processing based on Dominance Graph (DGSSGQ), which aims to efficiently find the skyline groups on encrypted datasets. In DGSSGQ method, we first present the data preprocessing and encryption mechanism based on dominance graphs, which record the dominance relationships between points in the dataset. To save the query processing costs, we further present the maintenance of the encrypted dominance graph. To achieve secure calculation on the encrypted DG, we design Secure Inclusion Protocol (SIP), which enables the determination of the inclusion of the nodes in the DG in a group. Based on the encrypted DG and SIP presented, we propose the secure skyline group query processing method to find the skyline groups. Thorough analysis shows the security and complexity of the proposed query methods, and the results of extensive experiments on real and synthetic datasets illustrate the performance of our proposed methods.