| With the popularity of the mobile Internet,more and more mobile devices are connected to the Internet through WLANs.Therefore,higher and higher demands are placed on the performance of AP nodes.However,there are two problems that can seriously affect the performance of APs: This is due to increasing delay caused by excessive queueing and the 802.11 performance anomaly caused by multi-rate sites.In view of the above problems,based on the AP network protocol stack,this paper designs and implements a new queue management method for AP nodes,which can effectively solve the bufferbloat problem of the WiFi stack and eliminate the 802.11 performance anomaly.Mainly complete the following work:(1)Aiming at solving the bufferbloat problem of AP nodes,the active queuing management method for wireless network stack control network delay is designed based on the design idea of the active queue management method with control delay,and optimized for the TCP flow.When the congestion of the wireless network stack is detected,the congestion information is displayed by displaying the ECN method to avoid influence of the active packet loss method on the TCP congestion control algorithm.(2)For 802.11 performance anomalies in multi-rate sites of WLAN systems,accurate wireless channel transmission parameters are obtained through wireless the registers of hardware,and a queue scheduling method based on airtime fairness is designed.This method can not only eliminate 802.11 performance anomalies,but also ensure different TID queues of the same QoS priority for each STA are using a deficit round-robin scheduling method to guarantee the packet-to-queue rate of packets with different TID queues in the same QoS priority of each STA fairness.This queue management method is deployed in commercial APs for testing and analysis: The queue management method proposed in this paper can improve TCP throughput at least 15% with the premise of guaranteeing network delay and eliminating 802.11 performance anomalies.The solutions in this paper are all completed at the AP node and do not require any modification to the STA,so it can be well promoted and deployed. |
