Research And Implementation Of Multi-controller SDN Load Balancing Method Based On FPGA

Constantly innovated and developed the network technology has been.Recent years,as the most basic service: Internet has become widely used in our daily life,many aspects of our life have been more convenient.Shopping,online,remote video,mobile payment and other technologies have became significantly in our daily life.Although the high speed development of the network brings a convenience at the same time,the demand for network performance also increases rapidly.The architecture of traditional network is decentralized and complex.The needs of massive network affairs can't be satisfied as the limitations of the traditional networks.Software-defined network(SDN)technology separates the forwarding process(data plane)of network packets and the routing process(control plane)of network packets which can promotes network management,and configure an efficient network configuration through programming,reducing the stricted requirements for network equipment.Because the single SDN controller cannot meet the demand of data transmission in the current large-scale network,the distributed SDN structure based on the multi-controller is proposed as a hit research point.Although the cooperative work of multiple controllers not only brings flexibility and extensibility controlling,it also leads to the problem of load balance.Therefore,researchers have proposed the solution of SDN switch migration.However,at present,all the migration algorithms are implemented in the controller by software,which will generate additional load on the controller when running algorithms.There are also communication-consuming overhead when transferring results.To solve this problem,this paper designs a switch migration algorithm based on FPGA.The main innovative works of this article are presented as follows:1)According to the problem of load balancing in the subdomain controller of SDN,this paper proposes a switch migration algorithm based on FPGA.In the multi-controller collaborative model based on FPGA,we realize switch migration algorithm by genetic algorithm.This algorithm treat the network load balance as the objective function,and encodes the switches that need to be migrated to when ensure the minimum change of the original network topology.Finally,we set up a test environment to evaluate and verify theimprovement of our migration method.2)Aiming at the problem of network congestion caused by excessive network traffic,this paper designs a shortest path algorithm based on FPGA.Floyd-Warshall algorithm is implemented to solve this issue in FPGA.With the acquired network topology,the shortest paths of any two control domains are obtained and stored in the FPGA at one time.In this paper,we test the two proposed schemes through experiments.The board level simulation results of the switch migration algorithm show that the algorithm can correctly select the switch to be migrated and the load balance after migration can be effectively reduced.Plate-level simulation and performance results of the shortest path algorithm show that the algorithm has a low delay,and the FPGA can correctly send data information through the algorithm.