Reseach Of Wlan Access Technology Based On Sdn

With the rapid growth of wireless data and wireless terminals, current network architecture and access point (AP) selection mechanism gradually can’t meet the increasing needs of users. Due to the limitation of the traditional network architecture, few improvements can be made for the current network, so we need to break the shackles of the current network architecture, and create a new network architecture to cope with growing network size.Software Defined Network (SDN) has attracted many researchers as a new network architecture which has separation of control and forwarding plane, programmability, high innovation features. An architecture which combines centralized control, virtualization features in SDN and the flexibility, mobility features of WLAN technology will greatly solve the current problems of the wireless network. And a new AP selection mechanism based on the SDN-WLAN architecture which is proposed in this paper, not only complements the study of this new network architecture, but also reforms the current AP selection mechanism.By analyzing the traditional WLAN network architecture and a variety of existing SDN wireless architectures, this paper raised a new SDN-WLAN network architecture, described the design of the work flow, virtual AP and controller, and simulated the architecture in the multi-path scenario. The simulation verified that the new architecture had improvements on system overall throughput and average delay, compared to the traditional CAP WAP architecture.Besides, this paper proposed a new AP selection mechanism based on SDN-WLAN architecture. By collecting a variety of parameters which can characterize APs’performance, the mechanism can select an AP that can offer a better performance than other candidate APs for users to access. Compared with traditional mechanism that only considers single parameter, multi-parameters of SNBE can assess the performance of APs more accurately. So SNBE mechanism can select an AP with less load and better transmission performance, and improve throughout and average delay of network. Simulation results show that compared with the traditional AP selection mechanism and the MPD mechanism based on the average delay of probe respond frame, the performance of SNBE mechanism is better.