Research On Topology Reconstruction Based On SDN

With the development of the network application,the conventional network gradually cannot meet the requirements of the network application.To a certain extent,the requirements of the network application can be satisfied by the software defined network(SDN)which divides the control function and the forwarding function in the traditional network.SDN receives great development with the OpenFlow protocol put forward.During the SDN development,NetFPGA is emerged,which satisfies the requirement for the flexible forwarding equipment.In this paper,the SDN-based reconstruction of the satellite dynamic network topology is implemented and a dynamic topology routing strategy based on SDN is proposed.Mininet is installed and the dynamic satellite network topology is built by using the programming interface provided by Mininet.The open network operating system(ONOS)is installed,and it is used to control the satellite network.The shortest path strategy is used for routing.The simulation results show the following two points.First,the link delay keeps stable in the dynamic topology and it is basically consistent with the link delay in the static topology.Second,the link rate will be affected by the handover between the satellite and the ground station.The minimum rate is appeared periodically.However,it can be quickly restored.The development environment for NetFPGA SUME is established.A high speed switch is implemented on NetFPGA SUME with modular structure.The file transfer function and the video transmission function are tested for the NetFPGA SUME high speed switch.The file transfer test shows that the receiver can receive the 1.09 GB file same with the transmitter in 7 seconds.And the video transmission test shows that the video can be played in the receiver during the transmission process.The link bandwidth is tested by the iperf3.The test result shows that the link bandwidth is about 7 Gb/s.