While there are many issues I have with this paper, http://pure.abdn.ac.uk:8080/portal/files/27528015/CK_AQM.pdf one of the things I found encouraging from looking at the graphs that cubic vs codel starts outperforming ared significantly, in terms of packet drop, at about 2.5mbits. In the attached graph I combined the comparison in figure 7 from that paper to directly compare ared vs codel (forgive me my lousy gimp skills), and the trendline for drops at speeds > 2.5Mbits is strongly encouraging vs a vs everything else. As to why codel drops more than ared below that speed, there are multiple explanations, notably that htb or BQL are buffering up a packet and this leads to an effective path length in excess of a mtu in size. Kathie long ago suggested disabling the ns2 inhibit at a mtu as it was a good idea in the ns2 model which had no underlying network layers to deal with, but not so much in the real world. the attached patch does that. I'm a little dubious as to what it will do in the case of TSO, and will try to have a sane testing regime for it in some future version of cerowrt. (presently what we do in cerowrt's sqm system is increase the target and interval to account for an extra mtu's transmission rate at rates below 4mbit) Other options might be to change htb to peek at the next packet rather than buffer it up, or use cbq which so far as I know uses an estimate, rather than the actual nextpacket. -- Dave Täht