SLS-STQ: a Novel Scheme for Securing Spatial-temporal Top-k Queries in TWSNs-based Edge Computing Systems

A novel network paradigm of edge computing, namely TWSNs (Two-tiered Wireless Sensor Networks), has just been proposed by researchers in recent years for its high scalability and robustness. However, in the TWSNs-based edge computing systems, the storage nodes, which are located at the upper layer of the systems, are prone to be attacked by the adversaries because they play a key role in bridging sensor nodes and Sink, which may lead to the disclosure of all the data stored on them as well as some other potentially devastating results. In this paper, we study the integrity-and-privacy preservation problem for spatial-temporal Top-k queries in the TWSNs-based edge computing systems, and propose a sequence-encryption-based lightweight scheme named SLS-STQ (Sequence-encryption-based Lightweight Scheme for Securing Spatial-temporal Top-k Queries) to solve the problem. In SLS-STQ, three algorithms, namely the report preparation algorithm, the query processing algorithm and the integrity verification algorithm, are designed for the sensor nodes, the storage nodes and Sink respectively. Theoretical analysis shows that SLS-STQ is able to achieve both the integrity validation and the privacy preservation with low computation complexity, and simulation results show that SLS-STQ is much more efficient than the related state-of-the-art schemes.