A Channel-Aware Scheduling Algorithm for Improving TCP Fairness

In wireless local area networks (WLANs), the greedy closed loop control nature of TCP and the performance anomaly of wireless channel lead to the up/down and time unfairness problems between TCP flows. To achieve the wireless channel usage time fairness between the uplink and downlink TCP flows, we propose the up/down time fair LAS (UDTFLAS) scheduling algorithm. Taking into account the transmission rate and the direction of each TCP flow, UDTFLAS gives the higher transmission probability to the TCP flows with the higher wireless data rate, as well as in the downlink direction. Analysis and simulation results show that UDTFLAS achieves the up/down time fairness, per-flow throughput protection, and great increase in total network throughput.