Context-Aware Optimization on Medium Access Delay for High-Density 802.11n Wi-Fi Network

With demands from increasing population of Wi-Fi devices, diversification of application services, and high-density deployment of APs, we need more care about the Quality of user Experience in 802.11 Wi-Fi networks. In this paper, we propose a context-aware optimization method with bursting transmission to reduce medium access delay of clients in highload scenario and improve effective number of clients in high density scenario of 802.11n network. To determine the time to switch MAC frame transmission modes, we choose the channel utilization rate to indicate the "channel busy time". We switch transmission modes once the channel utilization rate is higher than a fixed threshold. We implement this method on Atheros 9340 chips and evaluate it on the performance of End-to-End transmission delay with TCP scripts instead of Ping commands with Chariot tools in our prototype of 802.11n Wi-Fi APs. The experimental results show the proposed method can improve the effective client number of APs and reduce access delay in the situation of high-density clients.