Research On Routing Technologies In Heterogeneous Wireless Mesh Network

In recent years, Wireless Mesh Network (WMN) has been developed rapidly. It is one kind of multi-hop wireless self-organization network with some benefits, like flexible networking, broadband, good compatibility and low cost. Now WMN is one hot solution for the bottleneck breakthrough in the scenario of "last mile" broadband wireless access. In addition, heterogeneous property becomes more and more obvious with the fast development of various networks, e.g. cellular mobile communication network, Wireless Local Area Network(WLAN), Wireless Metropolitan Area Network (WMAN). Since WMN has good convergence capability for heterogeneous network, it is of great importance to make some research on the routing technologies.In this thesis, firstly the WMN architecture, features, standardization progress and application services are introduced. Main research work focuses on the analysis of the routing protocols and its further application in heterogeneous convergence field. Then, regarding to the multi-gateway offload balance problem and routing decision optimization, a new routing algorithm based on anycast mechanism is proposed, and implementation is performed through improving AODV (Ad hoc On-demand Distance Vector) protocol.The innovative points in the proposed algorithm include:1. Gateway selection depends on joint performance parameters of both gateway and routing. In contrast to the current routing only selection method, the proposed decision method is more comprehensive and appropriate.2. The selection decision is further optimized by taking account of different QoS demands of various networks in heterogeneous wireless Mesh network, so as to satisfy different QoS requirements.About the simulation platform, current NS2is lack of the support for the heterogeneous network. Therefore, NS2functions are extended in terms of3perspectives:using the multi-channel multi-interface mechanism to realize the convergence; using multi-layer address mechanism to connect the wireless and wired networks; add the gateway function into the model of mobile nodes. As a result, such platform is enabled to provide the data communication among internet, WMN, WSN and WLAN, and much easy to extend.Finally, performance evaluation is done in this new platform. Simulation results reveal that the proposed algorithm can efficiently achieve the offload balance for multi-gateway, and enhance the latency, packet loss rate as well as throughput. Specifically, the WSN data latency is highly reduced, and WLAN packet loss rate is also greatly decreased.