Traffic-aware decentralized AP selection for multi-rate in WLANs

AP selection problem is one of the major issues in infrastructure WLANs. Recently, many authors in the literatures have proposed a novel AP selection scheme which can provide better performance (e.g. aggregated throughput, load balancing) than RSS-based legacy scheme. However, they have presented the schemes with non-practical assumptions, e.g. they have assumed that adjacent APs are configured with orthogonal channels and each station transmits the data frame using a single data rate. As we have studied, adjacent BSSs' transmission and multiple transmission rates impact the network's performance. In this paper, we propose a practical traffic-aware AP selection scheme considering the factors previously mentioned. By exploiting the Retry field in the MAC header as feedback about channel conditions, we can infer the network conditions, and each client can select the `best' AP in terms of expected throughput. We demonstrate the effectiveness of our solution by comparing to existing approaches through ns-2 simulation.