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

## TL;DR

This paper introduces DyWi, a decentralized online primary channel selection algorithm for dynamic channel bonding in high-density WLANs, improving throughput and delay by considering channel activity beyond occupancy.

## Contribution

It proposes a novel, lightweight primary channel selection method that accounts for secondary channel activity, enhancing WLAN performance in dense environments.

## Key findings

- Significant throughput improvement observed in simulations.
- Reduced average delay with the DyWi algorithm.
- Effective in high-density WLAN scenarios.

## Abstract

In order to dynamically adapt the transmission bandwidth in wireless local area networks (WLANs), dynamic channel bonding (DCB) was introduced in IEEE 802.11n. It has been extended since then, and it is expected to be a key element in IEEE 802.11ax and future amendments such as IEEE 802.11be. While DCB is proven to be a compelling mechanism by itself, its performance is deeply tied to the primary channel selection, especially in high-density (HD) deployments, where multiple nodes contend for the spectrum. Traditionally, this primary channel selection relied on picking the most free one without any further consideration. In this paper, in contrast, we propose dynamic-wise (DyWi), a light-weight, decentralized, online primary channel selection algorithm for DCB that maximizes the expected WLAN throughput by considering not only the occupancy of the target primary channel but also the activity of the secondary channels. Even when assuming important delay costs due to primary switching, simulation results show a significant improvement both in terms of average delay and throughput.