Dynamic Channel Bonding in Spatially Distributed High-Density WLANs

Abstract

In this paper, we discuss the effects on throughput and fairness of dynamic channel bonding (DCB) in spatially distributed high-density wireless local area networks (WLANs). First, we present an analytical framework based on continuous-time Markov networks (CTMNs) for depicting the behavior of different DCB policies in spatially distributed scenarios, where nodes are not required to be within the carrier sense range of each other. Then, we assess the performance of DCB in high-density IEEE 802.11ac/ax WLANs by means of simulations. We show that there may be critical interrelations among nodes in the spatial domain -even if they are located outside the carrier sense range of each other -in a chain reaction manner. Results also reveal that, while always selecting the widest available channel normally maximizes the individual long-term throughput, it often generates unfair situations where other WLANs starve. Moreover, we show that there are scenarios where DCB with stochastic channel width selection improves the latter approach both in terms of individual throughput and fairness. It follows that there is not a unique optimal DCB policy for every case. Instead, smarter bandwidth adaptation is required in the challenging scenarios of next-generation WLANs.

Online Primary Channel Selection for Dynamic Channel Bonding in High-Density WLANs

“…However, the algorithm can be easily extended to consider other parameters such as latency. 3 We rely just on data from the last iteration for lowering memory demands and enabling fast adaptability in dynamic environments. Fig.…”

“…Although much has been understood from the works on CA and DCB in the literature, little has been assessed with respect to combining CA with DCB altogether in WLANs, particularly for high-density (HD) deployments. Nevertheless, while DCB has shown a tremendous potential to outperform traditional single-channel (SC) [1]- [3], its performance is severely tied to the CA. Especially, the primary channel selection is critical since it runs the backoff procedure of the carrier sense multiple access with collision avoidance (CSMA/CA) protocol.…”

Potential and pitfalls of Multi-Armed Bandits for decentralized Spatial Reuse in WLANs

“…Regarding the throughput model, we rely on the CTMN-based analytical tool for spatially distributed WLANs presented in (Barrachina-Muñoz et al, 2018b), referred to as SFCTMN. This tool captures the interrelations given in scenarios where nodes operating in the same channel are not required to be within the carrier sense range of each other.…”

AP-initiated multi-user transmissions in IEEE 802.11ax WLANs

“…Other research works related to IEEE 802.11ax development focus on the performance of WLANs in dense scenarios. They include: the evaluation of the dynamic sensitivity control mechanism [10], the use of basic service set (BSS) coloring [11], single-user (SU) performance [12], scheduling [13,14], static and dynamic channel bonding [15,16,17], channel access configuration [18], and more efficient but backward compatible alternatives to the legacy distributed coordination function [19,20].…”