Performance Evaluation and Improvement of Hybrid TCP Congestion Control Mechanisms in Wireless LAN Environment

In this paper, the authors first evaluate the performance of recent TCP variants for high-speed and long-delay networks in IEEE 802.11 wireless LAN environment through simulation experiments. They show that some of them still have well-known TCP unfairness property between uplink and downlink flows, and that there is another unfairness problem among uplink flows caused by the loss-based behavior of hybrid TCP variants. They, then propose an end-to-end-basis modification to TCP congestion control mechanisms to alleviate the unfairness problems, which activates the congestion control when detecting ACK packet losses.