The Wonder Shaper

bert hubert <ahu@ds9a.nl>
© Copyright 2002
Licensed under the GPL
Originally part of the Linux Advanced Routing & Shaping HOWTO

Before, without wondershaper, while uploading:
round-trip min/avg/max = 2041.4/2332.1/2427.6 ms
After, with wondershaper, during 220kbit/s upload:
round-trip min/avg/max = 15.7/51.8/79.9 ms

* Download version 1.1a, released 16th of April 2002.
* Download version 1.0, released 5th of March 2002.

Works on Linux 2.4 & higher.

If you get an error in the last two lines of the script, try this version of iproute instead: ftp://ftp.inr.ac.ru/ip-routing/iproute2-2.4.7-now-ss010824.tar.gz.

Goals

I attempted to create the holy grail:

* Maintain low latency for interfactive traffic at all times

This means that downloading or uploading files should not disturb SSH or even telnet. These are the most important things, even 200ms latency is sluggish to work over.

* Allow 'surfing' at reasonable speeds while up or downloading

Even though http is 'bulk' traffic, other traffic should not drown it out too much.

* Make sure uploads don't harm downloads, and the other way around

This is a much observed phenomenon where upstream traffic simply destroys download speed. It turns out that all this is possible, at the cost of a tiny bit of bandwidth. The reason that uploads, downloads and ssh hurt eachother is the presence of large queues in many domestic access devices like cable or DSL modems.

Valid HTML 4.01 Transitional