Routing Strategy Of Software-Defined Flying Ad Hoc Network

With the miniaturization and intelligent of UAV,flying ad hoc network(FANET)has become one of the research hotspots of unmanned aerial vehicle(UAV)cluster technology.FANET has been widely used in military and civilian fields due to its deficiencies,flexible selforganization and other features.With the increase of UAV applications,the tasks that need to be completed by FANET are gradually diversified and complicated,the business requirements in the network are becoming more and more complex,and the communication requirements for the FANET are getting higher and higher.With the limited network resources,the distributed routing protocol of the FANET is gradually difficult to meet the service quality requirements of different services.In order to solve the above problems,the idea of centralized control of the network resources by software-defined network(SDN)was introduced into FANET and proposed the concept of software-defined flying ad hoc network(SD-FANET).However,there are many problems that need to be solved urgently in SD-FANET.For example,the control overhead of the protocol used for topology information collection in the existing network is too large,which is not suitable for flying ad hoc network with limited resources.The centralized network is easy to be unavailable when the control node is damaged.In the centralized routing mode,the controller is easy to becomes the network bottleneck due to the high communication load.In order to solve those problems on SDFANET based on the UAV multi-hop communication environment,this paper conducts the following research:(1)Aiming at the high cost of topology discovery and the destructive problems in centralized networks,this paper designs the networking method of the SD-FANET.In this paper,the data plane and control plane are separated in the UAV multi-hop network.The data plane selection algorithm is implemented to limit the number of nodes that report control information and reduce the control overhead during topology discovery.The controller is selected from the data plane set through the controller selection algorithm,and the failure detection mechanism of the controller is designed to ensure that the network can recover quickly when the controller node fails,and improve destruction resistance of the network.(2)This paper proposes a hybrid routing method based on bandwidth constraints to solve the high communication burden of control nodes in centralized routing.In this method,the nodes in the network independently construct a two-hop neighbor information table as the basic routing table to complete the service transmission within two hops and reduce the routing request load of the control node.The controller uses a bandwidth-constrained routing algorithm to perform routing calculations.The algorithm selects a route based on the service bandwidth requirements and the bandwidth utilization,which can effectively reduce the endto-end delay of service transmission.This paper builds a SD-FANET environment using OPNET simulation software,conducts simulation experiments on the data plane and control plane nodes selection algorithms and the bandwidth-constrained hybrid routing algorithm proposed in this paper,and verifies the feasibility and the performance according to the simulation results.