Backoff algorithmic design for multi-radio multi-channel wireless networks

Abstract

With the standardization of IEEE 802.11s, wireless mesh networks may likely be deployed in future as the wireless networking infrastructures in cities and rural areas, due to their low budgeting needs upon comparing to those in wired networks. In 802.11, frame collisions occur in shared wireless medium, and the protocol executes truncated binary exponential backoff (BEB) algorithm for frame retransmissions. However, it has been known to give low overall 802.11 throughput performance. With the advent of multi-radio multi-channel 802.11s infrastructure, the traditional BEB algorithm should be modified to run in such a model with multiple frequency channels. In this paper, a novel backoff mechanism is designed to operate in a protocol for multi-channel wireless networks. In our design, a simple frame counting mechanism for detecting neighboring devices within one transmission hop is deployed. Through thorough simulations, the resulting multi-channel backoff algorithm provides sustainable high throughput performance.