Research On Cooperative Hybrid Routing Protocol For Hybrid W Ireless Mesh Network

Hybrid Wireless Mesh Network(WMN)combines the features and advantages of the backbone WMN and the client WMN,which is the most generic WMN.In hybrid WMN,the static mesh router has multiple interfaces with no energy constraints.The dynamic mesh client is different,usually with only one interface,and the energy is limited.As the routing protocol determines the path from the source node to the destination node to forward data packets,the routing protocol can greatly affect the network performance.Designing routing protocol which is adaptive for features of hybrid WMN can effectively improve the network performance.The existing research on routing protocols is aimed at homogeneous networks,such as ad hoc networks and backbone WMN.The current routing protocols designed for hybrid WMN are few and do not take into account the characteristics of mesh clients and mesh routers.These existing routing protocols do not make full use of stable mesh routers.Routing protocols are classified into proactive routing protocol,reactive routing protocol and hybrid routing protocol.Proactive routing protocol can find a good route for static nodes before sending packets.Reactive routing protocol is adaptive for mobile nodes,and only finds a way when some packets are needed to transmit.Therefore,a hybrid routing protocol combining the advantages of proactive and reactive routing protocols is well suited for hybrid WMN.However,the proposed hybrid routing protocol does not consider the network state,so it is of great value to design a hybrid routing protocol which can consider network characteristics and state in hybrid WMN.In this paper,to solve the problem that existing routing protocols designed for hybrid WMN do not consider the characteristics of mesh client and mesh router,an interference and energy-aware cooperative hybrid routing protocol(CHRP)is proposed for hybrid WMN.CHRP combines the advantages of proactive routing protocol and reactive routing protocol,improving the proactive and reactive routing metrics respectively.In the reactive routing protocol,a node-aware routing metric is designed.The channel state,interference and limited mesh client's energy are taken into account.The cross-layer approach is used to get information and avoid the additional overhead.In addition,CHRP also considers the gateway-oriented and client-oriented services in the network,which is closer to the real network scenario.NS3 simulation results show that CHRP has improved network performance in terms of average packet loss rate,network delay,network throughput,average energy consumption of mesh clients and minimum residual energy among mesh clients.On the basis of CHRP,this paper also proposes a load-aware cooperative hybrid routing protocol(LA-CHRP),which solves the problem that the existing hybrid routing protocols designed for hybrid WMN do not consider load in network.Therefore,LA-CHRP can reduce network congestion.LA-CHRP not only considers the characteristics of mesh client and mesh router,but also considers load.Mesh client and mesh router are set different load levels respectively.In the cooperative mechanism,for the gateway-oriented traffic,the load level is considered to use mesh router more reasonably,and only mesh router with good load condition will be selected as the access node.For client-oriented services,LA-CHRP uses node-aware routing metric to use mesh router in priority to make the selected routes more stable.When selecting mesh client,if the remaining energy is sufficient,the mesh client with lower load will be used to forward data packets.NS3 simulation results show that LA-CHRP can help hybrid WMN obtain high throughput,low latency and low packet loss rate in different network scenarios.The research of this paper provides a theoretical basis for cooperative hybrid routing protocol design in hybrid WMN.