Hi Valdis, I am in the process of doing an emulation of a dumbbell topology, on my linux box.

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I am using the RED qdsic.

You have our condolences. RED is probably not the best choice of qdisc, because it requires very careful tuning of multiple parameters.

I am using RED for the part of emulating a switch. Since most switches are use AQM of RED/ECN.

You might want to investigate using fq_codel, or for very new kernels, use the fq qdisc and the bbr congestion control method.

Yes. For the sending side, I am already using fq+bbr. -- 吾輩は猫である。ホームーページはhttps://introo.me <http://introo.me>。