Research On The Networking Technology In Software Defined Mobile Ad Hoc Network

Mobile Ad Hoc Network(MANET)is a form of wireless network that can be dynamically organized in a self-organizing manner in an environment without network infrastructure,and has been widely used in military,civil and other fields.With the continuous development of wireless communication technology and multimedia technology,the amount of communication in the network has increased rapidly,and business requirements have become more and more complicated.At present,MANET mostly uses a distributed networking method,due to the local visibility of nodes,it encounters bottlenecks in improving network quality of service and load balancing.Therefore,some researchers have introduced the concept of centralized control of Software-Defined Network(SDN)into MANET,and proposed the concept of SoftwareDefined Mobile Ad Hoc Network(SDMANET).At present,the research of SDMANET is still in its infancy,and there are many key technical problems that need to be solved.For example,existing networking methods cannot be well adapted to large-scale high-speed mobile networks,and have poor networking stability and large control overhead.These problems will lead to unreliable operation of SDMANET's infrastructure,so it is difficult to optimize Qo S based on it.In view of the above problems,this thesis takes the networking technology in SDMANET as the research entry point.The main research work and innovations of this thesis are as follows:Firstly,this thesis proposes a SDMANET networking method based on out-of-band control and backbone network optimization(abbreviated as B-SDMANET).This method takes into account the distributed characteristics of MANET and the characteristics of SDN centralized control.It uses a multi-mode radio station with dual channels as the underlying communication unit,in which data channels and out-of-band control channels are allocated for networking.The use of out-of-band centralized control improves the stability of the network,making it suitable for high-speed mobile MANET networks.In addition,this method uses the dominant set algorithm to select the dominant node in the network as the backbone node.Only the backbone node communicates directly with the SDN controller,reducing the number of nodes in the network that directly communicate with the controller,thereby reducing control overhead.Experiments show that this method can greatly reduce network routing control overhead in large-scale MANET networks.Secondly,this thesis proposes a centralized dynamic TDMA protocol based on backbone network(abbreviated as B-TDMA).The protocol takes advantage of the characteristics of SDN centralized control and uses the SDN controller as the central node of TDMA to unify time synchronization and time slot allocation for out-of-band control network nodes,thereby reducing channel interference in out-of-band control networks.Then,a dynamic slot allocation algorithm based on the backbone network is proposed to reduce the number of slots allocated by the out-of-band control network through the backbone nodes,thereby reducing MAC access delay and improving the out-of-band channel utilization.In this method,the control channel of the non-backbone node is closed to save energy consumption according to the characteristics of the limited energy of MANET.Finally,since there is currently no open source SDMANET simulation platform for experimentation,this thesis uses the RYU controller and Riverbed simulation software to build a B-SDMANET simulation platform,and designs the wireless Open Flow protocol(W-Open Flow)as the southbound interface for the communication between the controller and the switch.This thesis implements the B-SDMANET network node model,B-TDMA process model and W-Open Flow process model in simulation software,and designs multiple simulation scenarios to verify the feasibility and performance of the method in this thesis.Simulation results show that the method in this thesis is not sensitive to network scale,which can effectively reduce network overhead control and MAC access delay in large-scale networks,and improve network stability and MAC throughput.