"It's Your Turn": A Novel Channel Contention Mechanism for Improving Wi-Fi's Reliability

TL;DR

This paper proposes a new channel contention mechanism, “It's Your Turn” (IYT), that extends the existing Distributed Coordination Function (DCF) and aims at improving the reliability of distributed LBT by providing ordered device transmissions thanks to neighboring activity awareness.

Abstract

The next generation of Wi-Fi, i.e., the IEEE 802.11bn (aka Wi-Fi 8), is not only expected to increase its performance and provide extended capabilities but also aims to offer a reliable service. Given that one of the main sources of unreliability in IEEE 802.11 stems from the current distributed channel access, which is based on Listen-Before-Talk (LBT), the development of novel contention schemes gains importance for Wi-Fi 8 and beyond. In this paper, we propose a new channel contention mechanism, "It's Your Turn" (IYT), that extends the existing Distributed Coordination Function (DCF) and aims at improving the reliability of distributed LBT by providing ordered device transmissions thanks to neighboring activity awareness. Using simulation results, we show that our mechanism strives to provide reliable performance by controlling the channel access delay. We prove the versatility of IYT against different topologies, coexistence with legacy devices, and increasing network densities.

Figures (7)

• Figure 1: Channel access and packet transmission diagrams for two overlapping STAs. (a) BEB (b) DB, (c) IYT.
• Figure 2: Toy scenario formed by two BSSs. In (a), no packet losses occur when BSS 1 and BSS 2 transmit concurrently, while in (b), they do.
• Figure 3: CDF of the performance achieved by BEB, DB, and IYT in the 2-BSS toy scenario. (a) Throughput (no losses), (b) channel access delay (no losses), (c) throughput (with losses), (d) channel access delay (with losses).
• Figure 4: CDF of the throughput achieved with different combinations of coexisting mechanisms in the 2-BSS toy scenario. (a) No packet losses, (b) with packet losses. Each line represents the performance of a device implementing a given mechanism (BEB, DB, or IYT) when competing with another device using another mechanism (BEB, DB, or IYT). The throughput values of both BSSs are aggregated in the same line for the legacy case (BEB vs BEB).
• Figure 5: CDF of the throughput achieved by BEB and IYT devices in the 2-BSS toy scenario (no packet losses), for CW$_0\in\{5,6,16\}$ (CW$_0$ is always fixed to 16 for BEB). Each line represents the performance of a device implementing BEB (in red) when competing with another IYT device (in green).