Measuring TCP over WiFi: A Real Case

We present a measurement study of an operative WLAN. After briefly presenting the methodology used to generate traffic and measure performance indices, we present results focusing on the performance perceived by TCP connections, to understand the mechanisms which have a major effect on performance. We investigate the impact of TCP parameters, like the maximum congestion window, the effectiveness of link layer mechanisms such as RTS/CTS, and multirate transmissions. Rather than only presenting aggregate measures, we show results relative to individual TCP connections, considering throughput as well as TCP round trip time, congestion window and segment retransmissions.