Improved wireless TCP by discriminative control using loss cause reasoning

Abstract

TCP is originally developed for wired networks, which have lower packet loss from transmission errors. TCP controls the amount of packet transmission efficiently and the confidence of data transmission and high throughput is guaranteed. However the legacy wired TCP does not fit wireless networks which have high Bit Error Rate (BER) inducing frequent packet loss. In this paper, we discriminate the cause of packet loss and based on that, adapt the control algorithm so that the TCP used in wired networks is improved to perform well in wireless networks. The proposed algorithm distinguishes whether the reason for a packet loss is due to the network congestion or some random error, and accordingly adapts the congestion window and slow starts threshold value. For maintaining stable state after random error, the proposed algorithm keeps current values. Detailed simulations are provided to show how the detection of packet loss and the bandwidth estimation scheme serves to control excessive decrease of the congestion window caused by transmission errors in wireless networks. © Springer-Verlag Berlin Heidelberg 2006.