Performance Analysis of Multi-Channel MAC Protocols in Multi-Hop Ad Hoc Networks

Abstract

In recent years, multi-channel MACs have attracted considerable attention in wireless networking research. Motivation for research into multi-channel MACs is their potential to increase the capacity of wireless ad hoc networks by exploiting multiple orthogonal frequency bands. This potential has been confirmed by several simulation studies that reported promising results for multi-channel MACs. However, the analytical performance of these protocols is not well understood. In this work, we present an analytical framework for modeling the performance multi-channel MACs in multi-hop networks. We employ our framework to investigate the performance of three representative multi channel MACs: Asynchronous Multichannel Coordination Protocol (AMCP), Multi-Channel MAC (MMAC), and Slotted Seeded Channel Hopping (SSCH). The important findings of our analysis are: (1) SSCH outperforms AMCP and MMAC in both 802.11b and 802.11a scenario, (2) AMCP performs worse than MMAC in 802.11b because the overhead of AMCP's control channel is higher than that of MMAC's control interval, and (3) the overhead of AMCP's control channel becomes negligible in an 802.11a scenario and is outweighed by that of MMAC's control interval. For this reason, AMCP delivers better performance than MMAC in 802.11a scenario.