PPsky: Privacy-Preserving Skyline Queries with Secret Sharing in eHealthcare

Applying skyline queries to medical data can considerably benefit medical analysis in eHealthcare. However, as medical data often involves sensitive personal data, privacy concerns have become a significant impediment to the development of eHealthcare. Although several privacy-preserving skyline query schemes in eHealthcare have been put forth, they need a trusted platform to generate and assign secret keys for the multi-source scenario. In addition, those schemes incur non-trivial computational costs on resource-limited entities. To address these limitations, we propose a novel privacy-preserving skyline query scheme, named PPsky, based on arithmetic secret sharing, in which a series of secure protocols are designed to handle the basic operations in skyline queries. Security analysis illustrates that our PPsky scheme is privacy-preserving, and the evaluation results also validate the efficiency of our PPsky scheme.