Proposal, Implementation, and Evaluation of a QoS-Aware Routing Mechanism for Multi-channel Multi-interface Ad-Hoc Networks

Without any control mechanism, a wireless ad-hoc network is easily congested and the perceived quality of applications considerably deteriorates. Therefore, we need QoS control mechanisms to accommodate real-time multimedia application such as video conferencing, VoIP (Voice over IP), and remote monitoring while satisfying application QoS requirements. In this paper, we propose a new routing mechanism to support real-time multimedia communication by efficiently utilize the limited wireless network capacity. Our mechanism considers a wireless ad-hoc network composed of nodes equipped with multiple network interfaces to each of which a different wireless channel can be assigned. By embedding information about channel usage in control messages of OLSRv2, each node obtains a view of topology and bandwidth information of the whole network. Then, a source node determines a logical path on which application QoS requirements are satisfied. Through experiments on a simulator, our mechanism could achieve the packet delivery ratio of about 95% at the end-to-end delay of about 10ms. In addition, real-time traffic was more evenly distributed over the whole network.