Predicting external rogue access point in IEEE 802.11 b/g WLAN using RF signal strength

With the widespread use of Wireless Local Area Network(WLAN)s Rogue Access Point(AP)s have become a severe security threat to the WLAN user. In a recent survey, Gartner reported that nearly 20% organizations have rogue access points inside their premises. WLANs have evolved with the rapid development of wireless technologies. Nowadays WLAN is present in almost everywhere from a school to a Multinational Company, a coffee shop to public transport. Their presence has become indispensable in any organization, as they are cost effective and easily deployable. Predicting rogue access points with proper accuracy and using low cost is a very challenging task. In this paper, we propose an external rogue access point prediction mechanism which uses radio frequency(RF) signal strength to predict a rogue access point. The prediction of rogue access points happens in two phases: Distance Calculation and Access Point Prediction. The first phase uses FSPL transmission model to calculate the distances of various APs from the user device by collecting strength of radio frequency signal from each AP. The second phase predicts whether an external AP is rogue or not based on the calculated distance and by comparing it with a threshold distance. We have tested our mechanism by implementing it in an Android based smartphone and it was successfully able to predict rogue APs with acceptable accuracies. The threshold values were decided based on extensive experiments conducted in IIT Guwahati campus.