Multipath Qos Routing Algorithms In Wireless Mesh Networks

Wireless Mesh Networks is one of the most important evolution trends for traditional wireless telecommunication. As a broadband wireless network technology characterized with self-organization and multi-hop, Wireless Mesh Networks have many advantages such as high speed, easy to setup and low cost. Wireless Mesh Networks technology can overcome shadow Effect and signal fading, it can increase coverage of wireless networks, and work with minimum wired network support in a wide range area. Wireless Mesh Networks can support different wireless access technology, such as IEEE802.11, IEEE802.15, and IEEE802.16, and provide convergence with different kinds of networks. Wireless mesh network has the ability of self-organization and self-repair, traffic can be routed via the neighbor if one node is out of usage.Routing is one of the key functions of wireless mesh networks, and routing protocol study is the hot topics in wireless mesh network research area. Compare to routing in traditional wireless networks, a series of new issues need to be solved in Wireless Mesh Networks. The limited band, the defect of wireless channel, multi-hop, and dynamic topology introduced new challenges to design high performance routing protocol. It makes sense to do academic research and application study. The target of this thesis is to analyze and research the routing protocols in Wireless Mesh networks.Firstly, this thesis introduces the background knowledge, network framework and characteristics of Wireless Mesh Networks. It discusses the factors that impact the design of routing in Wireless Mesh Networks, also compare the popular routing protocols.The thesis discussed the Ad hoc On-Demand Distance Vector routing protocol and analyze the shortage of routing metrics and routing path redundancy, then raise a multi-path QoS routing protocol named AODV-MM based on AODV routing protocol. It use end to end ETX to replace the minimum hop count as the link metric to make the path selection more reasonable because it consider the impact of link layer. In order to improve the routing reliability and redundancy, AODV-MM adds the support to multi-path. The simulation result on NS-2 platform shows that the AODV-MM improves the average packet loss, average packet delay and the network throughput. AODV-MM is more suitable to be used in Wireless Mesh Networks in which reliable data transmission is needed.