Research And Implementation Of Mobile Handoff Method Towards Software Defined Networking

With the rapid development of software-defined networking(SDN)technology,more and more studies have been conducted on software-defined wireless networks,and mobile devices' handoff between different access points(APs)has become an unavoidable problem.Because of the features such as centralized control and unified view of information across the entire network SDN has,it presents certain advantages in handover control optimization.Therefore,it is of great significance to research the mobile handoff methods in SDN.In software-defined wireless networks,dynamic changes of network traffic cause load imbalance among access points.At the same time,terminal's mobility leads to non-optimum forwarding paths and large signaling overhead.In this paper,a network-side initiative handoff method is proposed using the open programming interface of SDN controller.The method includes a handover decision algorithm and a traffic redirection algorithm.First,in the handover decision algorithm,the user's mobility level and the user's resource occupancy rate of AP are taken into consideration to generate the user's handover weight value,then the user set to be switched is selected.And the non-cooperative game method is used to implement dynamic scheduling of network traffic.The simulation experiments of the algorithm are conducted in the Mininet-Wifi and MATLAB environment,and the analysis shows that the algorithm can achieve uniform distribution of network traffic and improve user throughput.Then,aiming at the problem of forwarding path optimization after multiple users move,this paper first models it as a set coverage problem.Then an ant colony algorithm-based multi-users redirection node selection algorithm is proposed to achieve optimized configuration of the forwarding paths after multi users' mobility.The simulation test of this method is conducted in MATLAB environment,and the analysis verifies that the algorithm can optimize the mobile forwarding path and reduce the signaling overhead of the controller.