Research On Localization Algorithm And Security In Wireless Sensor Networks

Wireless sensor networks(WSNs)has wide potential application in military,industry,agriculture,and environmental monitoring areas.As one of the vital technologies in WSNs,node localization is the basis of many WSNs-based applications.On the one hand,accurate position information is a key to WSNs-based applications;on the other hand,the resources of sensor nodes are very limited,including energy,storage capacity,etc,and sensor nodes are often deployed in harsh environments.So energy consumption and security can not be ignored in the process of node localization.In this paper,we studied positioning accuracy,energy consumption and security of DV-hop,which is a classical range-free localization algorithm.The main work we have done is as follows:(1)The proposed localization refinement algorithm,called as CVLR,combine a simple search-based method and position correction vectors to resolve the DV-hop's hop-distance ambiguity problem,which can lead to adjacent unknown nodes localized at the same or very close positions.CVLR can make full use of the relative position relationship of 1-hop neighboring nodes(called as CVLR1),or 1-hop and 2-hop neighboring nodes(called as CVLR2),to iteratively refine their localization positions.Simulation results show that the localization accuracy of CVLR1,CVLR2 are obviously higher than that of DV-hop.In fact,the localization accuracy of the two algorithms is increased by 41.12% and 56.61% respectively.(2)Firstly,we analyze the energy consumption of DV-hop,CVLR1 and CVLR2 algorithms.In order to combine the high accuracy of CVLR2 and the low energy consumption of CVLR1,we propose an improved CVLR algorithm(ECVLR)that emphasize to optimize the communication energy dissipation of CVLR2.ECVLR algorithm is still able to benefit from 1-hop and 2-hop neighbors' information to refine its positions;on the other hand,it can drastically reduce communication overhead.Simulation results show that compared with CVLR1,the localization accuracy of ECVLR algorithm is increased by 21.37%,and compared with CVLR2,the energy consumption is decreased by 86.69%.ECVLR algorithm has a good balance between the positioning accuracy and energy consumption,which is a kind of localization algorithm with high energy efficiency.(3)we propose a spoofing attack model with normal nodes compromised in the DV-hop localization procedure and analyze the effects of the spoofing attack.Then,a DV-hop secure localization scheme against the spoofing attack is proposed.Firstly,for the normal nodes,we putforward a detection mechanism,based on transmitting-forwarding information consistency,to detect malicious nodes.Secondly,for the Sink node,we put forward a detection mechanism,based on message forwarding chain,to identify the malicious nodes.Finally,when the Sink node detects that there has spoofing attacks in the networks,it broadcasts malicious nodes and then restarts the position process.The simulation results illustrate that the proposed secure localization scheme can efficiently filter the malicious nodes and the positioning performance of secure localization algorithm is similar to the normal DV-hop positioning.In fact,compared with normal DV-hop,the localization accuracy of secure localization algorithm is only decreased by 0.79%.So the proposed algorithm can effectively solves the impact of the spoofing attack on the DV-hop positioning process.