# Secure Multidimensional Queries in Tiered Sensor Networks

## TL;DR

This paper introduces secure schemes for multidimensional queries in tiered sensor networks, focusing on reducing communication overhead and addressing security threats from node compromises.

## Contribution

It proposes novel secure query schemes for range, top-k, and skyline queries, including the first solutions for securing top-k and skyline queries in tiered sensor networks.

## Key findings

- SRQ achieves lowest communication overhead among prior works.
- First secure top-k query scheme in tiered sensor networks.
- First secure skyline query scheme in tiered sensor networks.

## Abstract

In this paper, aiming at securing range query, top-k query, and skyline query in tiered sensor networks, we propose the Secure Range Query (SRQ), Secure Top-$k$ Query (STQ), and Secure Skyline Query (SSQ) schemes, respectively. In particular, SRQ, by using our proposed \emph{prime aggregation} technique, has the lowest communication overhead among prior works, while STQ and SSQ, to our knowledge, are the first proposals in tiered sensor networks for securing top-$k$ and skyline queries, respectively. Moreover, the relatively unexplored issue of the security impact of sensor node compromises on multidimensional queries is studied; two attacks incurred from the sensor node compromises, \emph{collusion attack} and \emph{false-incrimination attack}, are investigated in this paper. After developing a novel technique called \emph{subtree sampling}, we also explore methods of efficiently mitigating the threat of sensor node compromises. Performance analyses regarding the probability for detecting incomplete query-results and communication cost of the proposed schemes are also studied.