On Selfish Configuration in Wi-Fi Tethering

Due to the ease of setting up a Wi-Fi hotspot and the availability of readily configurable mobile operating systems, Wi-Fi tethering can be abused by misbehaving users to gain an unfair advantage in throughput performance. In this paper, we study the problem of detecting selfish nodes in Wi-Fi tethering environments. In particular, selfish nodes can manipulate carrier sensing thresholds to exploit recent advances in physical-layer concurrent transmission technologies as well as short link distance in a tethered network so as to achieve unfair throughput gains while evading detection. We propose a new MAC-layer detection algorithm based on frame sequence numbers that accurately detects selfish nodes.