Research And Simulation Of Multi-constrained Qos Routing Protocol In Wireless Mesh Networks

As the modern technology of networks developes rapidly, the Wireless Mesh Network (WMN) come to spring. WMN is a network with the feature of high transmission rate, self-organization and multi-hops. As a new broadband wireless access system, Wireless Mesh Networks possesses the merits of WLAN and wireless Ad Hoc networks, so it has a great future for application. With the improvement of network Quality of Service requirements and continuous expansion of network scale, QoS routing has become an important research direction in WMN. QoS routing protocol performs great function on the optimization of network performance. So the multi-constrained QoS routing algorithms and related technologies of WMN are studied in this paper.Firstly, the basic knowledge of the WMN, including network topology, the main features, applications, and common routing protocols in WMN are introduced. QoS-related knowledge and Wireless Mesh Network QoS routing protocols have also been studied and summarized.Secondly, taking bandwidth, packet loss rate and the routing hops into account, the factors which affect the performance of WMN are analyzed briefly. And a new routing metric and its calculation method are proposed. On this basis, a multi-constrained QoS routing protocol (MQR) is designed, which can satisfy bandwidth and delay constraints of the data flow.Again, this paper analyzes the lack of flat routing protocols, and makes further improvement about the MQR protocol. Then a clustering-based multi-constrained QoS routing protocol (CMQR) is proposed, which can address the limited scalability of the flat routing protocol effectively.Finally, using simulation tool NS2, this paper carries out simulation analysis on the proposed protocols, and compares them to the other protocols about the packet average delay, packet transmission rate and protocol overhead. Simulation results show that the proposed protocols have lower control overhead, and they can reduce the average packet delay, and improve packet transmission rate effectively.