Minimising RTT across homogeneous 802.11 WLANs with CAIA Delay-Gradient TCP (v0.1)

Common loss-based TCP algorithms (such as NewReno) are known to induce significant additional latency over 802.11 wireless LANs (WLANs), negatively impacting multimedia traffic sharing the same network. Using live experimental trials (under FreeBSD 9.0 on the Emulab 802.11 testbed) we show that CAIA's delaygradient TCP (CDG) version 0.1 induces two to seven times lower latency than NewReno and CUBIC in homogeneous 802.11 WLAN environments while achieving equivalent goodput. This is beneficial in 802.11 WLAN environments where TCP and multimedia traffic must coexist and the network administrators have control over each end-host's choice of TCP algorithm.