The Research Of Multipath Routing Protocols For Multi-channel Wireless Mesh Networks

As a new network technology, Wireless Mesh Networks have the advantages of self-organizing, self-configuring, self-healing and the integration with other heterogeneous networks. In the networks, packets are forwarded on wireless multi-hop routing to or from the gateways connected to the Internet. Traditional routing protocols have some limitation in adapting to dynamic changes in WMNs, which does not help to the network capacity, then the concept of On-demand Multipath Routing was proposed to solve this problem.Firstly, a On-demand Multipath Routing Protocol(ODMR_q) is presented in this paper on the basis of Q-learning algorithm. If the primary route is broken at some points, the routing protocol can transmit data packets by alternate routes which are established in the routing discovery process. The Q-learning algorithm can adjust routing survival time according to network status, which can decrease the routing control overhead and optimize the network throughput.Secondly, we study the on-demand multipath routing with the multi-channel case, efficient channel assignment allow making full use of the channel spectrum and thereby reducing interference among wireless links. Simultaneously, we introduce a new weighted end-to-end delay(WEED) metric taking not only the queuing delay and transmission delay, but also the channel diversity and intra/inter-flow interference into account, which can represent the end-to-end performance accurately.Finally, simulating the routing protocols using the OPNET software verifies the performance of these proposed protocols, simulations reveal that the modified protocols can enhance the network performance to a great extent in Wireless Mesh Networks.