Design And Implementation Of Multi-gateway Wireless Mesh Network Based On 802.11s

Wireless Mesh Network technology is on developing towards extensive industry applications.WMN has advantages such as multi-hop wireless transmission,self-organized construction,high survivability,high scalability and easy-to-deployment.In the application scenario of Intelligent Transportation System,the WMN has the characteristics including large-scale network,strong terminal mobility,and most convergent traffics.These characteristics easily lead to bottleneck at gateway node.Development of multi-gateway Wireless Mesh Network with load balancing is practical.The paper gives an overview of WMN technology.The implementation methods of multi-gateway and load balancing strategies for WMN are analyzed and compared.On the research background of the paper,a multi-gateway WMN method and its load balancing scheme based on dynamic clustering are proposed based on DEEE802.11s and its default routing protocol HWMP.1.A method of selective BPDU discarding and frame marking is designed to solve the problem of network loops and broadcast storm because of multi-gateway introduced.2.The gateway is used as the cluster head.The gateway MAC address is used as the cluster's identifier and added in the RANN and PREQ frame to realize the cluster selection and the cluster partition of the non-gateway nodes.Thus,the dynamic clustering of the network is realized.3.The processing of PREP and PERR frame is modified to maintain the proactive tree routing,moreover to realize the smooth transition of routing table and gateway load.4.Non-gateway nodes select optical gateway considering both path metric and gateway load to realize load balancing of gateway.5.The one-hop neighbor nodes belonging to different clusters communicate with each other directly to optimize the cross-cluster communication.Finally,the key technologies of this multi-gateway WMN load balancing strategies based on dynamic clustering are implemented via programing on Linux platform.Moreover,the paper set up several networks with different topology for experiment.The experimental results show that the multi-gateway method and its load balancing strategies have achieved the desired effects in the key technologies.These technologies is feasible and practical.