A Study on Detection Method of Selfish Terminal Using Manipulated MAC Parameters over WLAN

In the wireless LAN based on IEEE802.11, each wireless terminal can obtain fair communication opportunity using CSMA/CA (Carrier Sense Multiple Access with Collision Avoidance). However, because each terminal has MAC parameters such as Contention Window (CW) and Distributed InterFrame Space (DIFS), it is possible that these parameters are manipulated for throughput improvement. This study refers to the terminal using manipulated MAC layer parameters for throughput improvement as a selfish terminal. If the selfish terminal exists, it affects the throughput of normal terminals using default parameters. Therefore, a mechanism to detect the selfish terminal has become one of important technologies. The existing methods try to detect the selfish terminal that always uses the manipulated MAC parameters. However, they did not consider the case when the selfish terminal tries to hide the manipulation (i.e., adaptive cheating). Therefore, in this paper, we propose a detection method for the selfish terminal using adaptive cheating. Next, we evaluate the proposed method by simulation experiments. As a result, we found that the proposal can be used for detection of the selfish terminal with adaptive cheating in the specified environment.