Research On Rogue Access Point Indoor Positioning Based On Reference Points Optimization

With the popularity of smart devices and the rapid development of wireless technology,wireless access points are widely deployed.Along with this,the security problems of wireless communication are becoming more and more prominent,especially the privacy leakage caused by rogue APs.The current solutions mainly focus on the rogue AP detection,but the detection algorithm usually requires a tedious verification process and does not solve the problem from the source.Therefore,rogue AP localization is an urgent matter for maintaining wireless security.However,the existing rogue AP positioning algorithms either need to deploy dedicated hardware facilities in advance,or the positioning accuracy is not high.To this end,we designed and implemented an AP real-time positioning system,which can accurately localize rogue APs with minimal infrastructure costs.We summarize the main content of this paper as follows:(1)Considering that the range-based positioning algorithm usually randomly selects several positions as reference points and ignores the influence of the reference points selection on the positioning results.Therefore,we dynamically select the reference point with the strongest signal strength for position estimation based on RSSI gradient direction.And the position coordinates of the reference point can be obtained dynamically by the distance measurement algorithm.Experiments show that the reference point determined by this method is relatively closer to the rogue AP,and the RSSI observation value is relatively less interfered by the indoor complex environment,which helps to further improve the positioning accuracy.(2)In order to estimate the location of the rogue AP,we use an improved gradient descent algorithm to search for the least squares solution.The algorithm can be divided into two stages: Firstly,without the reliability information of the reference point,the objective function is minimized to obtain a preliminary estimate of the location of the rogue AP.Then,the distance residuals of each reference point are calculated based on the preliminary estimated value,and we assign different weights according to the ranging error of each reference point,so as to reduce the influence of the reference point with greater signal attenuation on the positioning accuracy.Finally,we compare the proposed positioning method based on reference point optimization with the existing method based on random selection of reference points.Experimental results show that our proposed solution can effectively alleviate the positioning error caused by RSSI attenuation and achieve higher positioning accuracy.