Research On Reliable Topology Control Technology Of Wireless Network

With the rapid development of wireless networks,cloud computing,fog computing,edge computing and network virtualization technologies have prompted the emergence of a new architecture for wireless networks.According to the structure and characteristics of the wireless network,the entire wireless network can be divided into an edge network and a core network.This thesis mainly studies the reliable topology control technology of wireless networks.It includes two aspects: topology control in edge network and virtual topology mapping in core network.In edge networks,nodes can access wireless multi-hop networks through multi-hop and self-organizing.The transmit power of nodes directly affects network topology and performance.Therefore,topology control technology is needed to optimize topology.In core network,networking virtualization enables multiple virtual networks to share the same core network resources,and provides diversified services.Virtual network topology mapping is one of the core technologies of network virtualization.The research content of this thesis is summarized as follows:Firstly,aiming at the topology control problem of edge networks in wireless networks,this thesis takes the reliability and network capacity of wireless multi-hop networks as the optimization target of network topology control,optimizes the network through topology control,and bases on network model,topology optimization objectives,constraints and control methods.This thesis proposes three kinds of topology control algorithms to optimize the network structure,logical sector optimization-based network topology control algorithm,cluster-based sector segmentation network topology control algorithm and connected dominating set-based topology control algorithm.The simulation results show that the topology generated by the logical sector optimization-based network topology control algorithm has the characteristics of reliable network topology structure,and the network can be k-connected as much as possible with less transmit power and links.When the network is dense,cluster-based global sector segmentation network topology control algorithm and connected dominating set-based topology control algorithm have good network topology control effects by constructing virtual backbone network,which can ensure the reliability of the network topology.Then,aiming at the network virtualization problem of wireless core network,based on the core network,this thesis studies and analyzes the reliable mapping method of virtual network.Considering the reliability of topology mapping,the characteristics of node CPU resources and link bandwidth resources,load balancing and link interference,this thesis proposes a multi-path link mapping algorithm based on Multi-Commodity Flow.Ant colony algorithm is used to optimize the solution to obtain a more reasonable mapping scheme.The algorithm takes the cost of virtual network mapping as the objective function,utilizes the way of virtual node and link cooperative mapping,and implements multi-path mapping of virtual links by dynamically adjusting the number of path splits.The simulation shows that the proposed algorithm has good performance in mapping success rate,substrate network revenue,usage rate of resource and load balancing.At the same time,the service is still provided through the backup link when the substrate link is faulty,which enhances the reliability of the topology mapping method.