关键词: 无线网络, 丢包类型, 拥塞控制, NS3, Westwood

Abstract:

In view of the large interference of the wireless network link and the high bit error rate, the TCP Westwood algorithm（TCPW） has excessive feedback on the packet when estimating the bandwidth, and lacks the shortcomings of distinguishing the type of packet loss during transmission. A TCPW congestion control optimization algorithm TCPW-F is proposed. The algorithm constructs the congestion factor by using the transmission rate and the like as the basis for judging the type of packet loss, and further adjusts the congestion window when the noise packet is lost, avoids the window drop caused by the unrelated noise packet loss, and improves the transmission efficiency of the window in this case. The simulation results show that the TCPW-F algorithm performs better in terms of delay performance, and the jitter per unit time tends to be stable. The packet generation rate is increased under the same channel bandwidth. The real-time throughput of the improved algorithm is significantly higher than that of the original algorithm. It has a certain noise packet loss sensing capability, and the TCP transmission quality of the wireless network is greatly improved.

Key words: wireless network, packet loss type, congestion control, NS3, Westwood