Architecture and algorithms for an IEEE 802.1 1 -based multi-channel wireless mesh network

TLDR

Although the 2.4 GHz and 5 GHz bands provide multiple non‑overlapping channels, most IEEE 802.11 multi‑hop ad hoc networks use only one channel, limiting their ability to exploit the full spectrum bandwidth and hindering deployment as ISP last‑mile or enterprise backbone networks. This work proposes Hyacinth, a multi‑channel wireless mesh network architecture that equips each node with multiple 802.11 NICs. Hyacinth’s design centers on dynamic channel assignment and routing, employing distributed algorithms that use only local traffic load information to assign channels and forward packets, and a 9‑node prototype built from commodity PCs with two 802.11a NICs was used to evaluate the approach. Simulation results demonstrate that even with just two NICs per node, Hyacinth can increase network throughput by a factor of six to seven compared with conventional single‑channel ad hoc networks.

Abstract

Even though multiple non-overlapped channels exist in the 2.4 GHz and 5 GHz spectrum, most IEEE 802.11-based multi-hop ad hoc networks today use only a single channel. As a result, these networks rarely can fully exploit the aggregate bandwidth available in the radio spectrum provisioned by the standards. This prevents them from being used as an ISP's wireless last-mile access network or as a wireless enterprise backbone network. In this paper, we propose a multi-channel wireless mesh network (WMN) architecture (called Hyacinth) that equips each mesh network node with multiple 802.11 network interface cards (NICs). The central design issues of this multi-channel WMN architecture are channel assignment and routing. We show that intelligent channel assignment is critical to Hyacinth's performance, present distributed algorithms that utilize only local traffic load information to dynamically assign channels and to route packets, and compare their performance against a centralized algorithm that performs the same functions. Through an extensive simulation study, we show that even with just 2 NICs on each node, it is possible to improve the network throughput by a factor of 6 to 7 when compared with the conventional single-channel ad hoc network architecture. We also describe and evaluate a 9-node Hyacinth prototype that Is built using commodity PCs each equipped with two 802.11a NICs.