Anti Jamming - Based Medium Access Control Using Adaptive Rapid Channel Hopping in 802.11: AJ-MAC

Abstract

802.11 networks have inherent security weaknesses due to wireless characteristics, especially physical layer jamming. Recent research shows channel hopping is a better way to combat jamming or interference compared to changing 802.11 operational parameters (such as, clear channel assessment threshold, rate, and packet size). However frequent channel hopping decreases network throughput, and intermittent channel hopping raises the jammer’s detection probability. We introduce an Adaptive Rapid Channel Hopping method using Dwell Window (DW) to mitigate these defects. This is a novel concept to adjust transmission time based on the jammer’s ability. That is, if a jammer successfully attacks a channel, the channel’s DW is decreased to reduce the jammer’s detection probability. In the case where there is no jamming, DW is increased to raise network throughput. In addition to this scheme, we introduce a Deception Mechanism that is another novel concept to make a jammer attack an unnecessary channel for a high throughput and a low probability of detection. Numerical analysis and simulation results show that the proposed scheme is more effective than those of prior studies.