Verifiable Top-kQuery Processing in Tiered Mobile Sensor Networks

Abstract

Verifiable top-kquery processing in tiered sensor networks, which refers to verifying the authenticity and the completeness of top-kquery results received by the network owner in tiered sensor networks, has received attention in very recent years. However, the existing solutions of this problem are only fit for static sensor network. In this paper, we try to solve the problem in a tiered mobile sensor network model, where not only static sensor nodes but also mobile sensor nodes existed. Based on the tiered mobile sensor network model, we propose a novel verifiable scheme named VTMSN for fine-grained top-kqueries. The main idea of VTMSN is as follows: it maps each of the positions where sensor nodes are in a static state to a virtual node and then establishes relationships among data items of each virtual node with their score orders, which are encrypted along with the scores of the data items and the time epochs using the distinct symmetric keys kept by each sensor node and the network owner. Both theory analysis and simulation results show the efficiency and the security of VTMSN.

A Comparative Study on Two Typical Schemes for Securing Spatial-Temporal Top-k Queries in Two-Tiered Mobile Wireless Sensor Networks

“…They cannot ensure the security of spatial-temporal Top- k queries in TMWSNs because of the special attacking models, whereby data items generated in the queried region are replaced with those generated by the same sensor node/nodes but not in the same region, exploited by the adversaries. To the best of our knowledge, VTMSN [ 9 ] and EVTopk [ 8 ] are the only two schemes that have been proposed to achieve the integrity preservation of the spatial-temporal Top- k queries in TMWSNs in recent years. In the following, we will review the two schemes in greater detail and compare them thoroughly through computer security theory and extensive simulations.…”

“…Here, the word “replacement” refers to the following two options: (1) replace the qualified Top- k data items with forged ones; (2) replace the qualified Top- k data items with real but unqualified data items. If the malicious storage node takes the first option, both schemes can detect the incomplete Top- k query results with a 100% probability according to Theorem 1 in [ 8 ] and Theorem 6 in [ 9 ] as long as no sensor node is captured by the adversaries; if the storage node takes the second option, according to Theorem 1 in [ 8 ] and Theorem 9 in [ 9 ], both schemes are also able to detect the corresponding incomplete Top- k query results. It is notable here that the methods for the two schemes prevent the storage node from replacing the qualified Top- k data items with data items that are not generated in the queried region.…”

“…It is notable here that the methods for the two schemes prevent the storage node from replacing the qualified Top- k data items with data items that are not generated in the queried region. The key idea of the methods used in the two schemes is to bind each data item with the location where it was generated using symmetric encryption [ 9 ] or a one-way hash chain [ 8 ]. By preventing the malicious storage node from undermining the binding relationship between each data item and its location, the two schemes are able to determine whether a data item is generated in the queried region or not.…”

“…In recent years, a novel paradigm of MEC, namely two-tiered mobile wireless sensor networks (TMWSNs) [ 8 , 9 ], has arisen and, because of the high robustness and scalability of its in-nature two-tiered network architecture, has attracted researchers’ attention [ 10 , 11 ]. As shown in Figure 1 , a TMWSN model, which is different from traditional flat wireless sensor networks (WSNs) [ 12 , 13 , 14 , 15 ], consists of two layers [ 16 ].…”

“…This paper focuses on the integrity preservation of spatial-temporal Top- k queries [ 17 ] in TMWSNs, where the selected top k data items should satisfy not only the time but also the geographic requirement [ 18 ] of a given Top- k query, and compares two typical schemes, namely VTMSN [ 9 ] and EVTopk [ 8 ]. The motivations of this paper are two-fold: It is a much more challenging problem to secure spatial-temporal Top- k queries in a mobile scenario than a static one in two-tiered wireless sensor networks, since malicious storage nodes may return false and/or incomplete Top- k query results to the sink with many more attacking options in a mobile scenario than a static one.…”