Investigation On One Bandwidth Adjustment-Based Wireless Mesh Network QoS Routing Protocol

Wireless Mesh Network (WMN) is a new broadband wireless network architecture developed from Ad hoc network and designed for civil use. It has the properties of reliability, self-organization and self-healing. The WMN is paid great attentions in academic and industrial fields. In this area, routing protocol and quality of service (QoS) strategy become the research focus, and the routing mechanism with QoS is one of the hottest topics.In the first part of the thesis, an end-to-end available bandwidth algorithm based on data slots statistic is proposed. It provides an accurate available bandwidth metric. Unlike the previous methods which could estimate the available bandwidth just between two intermediate nodes of the network based on data slots statistic; our method is capable of estimating the end-to-end available bandwidth. Introducing with the algorithm, the set of available transmitting slots and available receiving slots can avoid the problems of hiding terminals and exposing terminals effectively; and the heuristic strategy of end-to-end data slots scheduling can maximize available bandwidth. This algorithm has the property of simplicity and good-expansibility, which provides accurate available bandwidth information to the QoS routing.In the second part of the thesis, a QoS routing protocol based on bandwidth adjustment (QBR) is presented. QBR uses available bandwidth as the primary routing metric, and considers the property of applications, the priority of users and the available bandwidth in the network as other routing metrics. The preemption and compression theories are introduced. Four main advantages of QBR are improving the utilization of the network resource, avoiding unnecessary routing rebuilding, achieving network equilibrium and reducing the probability of connection rejection. The simulation results show that QBR has higher packets delivery ratio and improves the transmission quality of the network.