Understanding channel selection dynamics in dense Wi-Fi networks

This paper aims to explain and analyze a growing problem in dense-urban wireless networks, that of co-existence between low-cost residential access points (APs) and actively-managed service provider APs in overlapping spatial, frequency, and time domains. Through detailed simulations and testbed experiments, the impact of increasing density of highly-adaptive service provider APs on the performance of typical residential APs is measured in terms of their respective channel assignment schemes. Simulation results with dense deployment of up to 500 APs/sq.km. show the benefits of centralized channel assignments, even in the presence of independent APs. In addition, it is shown that for a fixed AP density, an increase in the percentage of AP under the centralized scheme results in an increase in the throughput of surrounding independent APs. The broader implications of the simulation findings are discussed in order to develop a better macro-level understanding of dense Wi-Fi networks.