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 From:  Danne <danne at djesigns dot com>
 To:  m0n0wall at lists dot m0n0 dot ch
 Subject:  Re: [m0n0wall] Traffic Shaping issue
 Date:  Tue, 27 Jul 2004 18:14:36 -0500
Mitch (WebCob) wrote:

>>My DSL ISP is SBC. They are quite lenient with their network. I have
>>asked several techs (both transport and ISP side) about filtering being
>>done, and there is nothing to hinder this specific traffic. I usually
>>test my connection at http://web100.rit.edu:7123/ . I always get
>>consistant >320kbps upload results from there. I've also never noticed
>>any problem uploading anything using my prior firewall, IPCop. Then
>>again, the main reason I started using m0n0wall was for the traffic
>>shaping ability. I never even considered this to be a problem until I
>>noticed my serving speed increase after disabling traffic shaping.
>Hmm.... Maybe I'm not being clear in what I'm thinking... and maybe I'm
>But it seems to me that just because you limit your throughput to X that you
>will ever see a transfer of X.
>It will always be X - network overhead.
>In a controlled environment, this will be VERY close to X, but in the real
>world, where your acks get delayed by the total trip time to the destination
>host, the throughput will be slower.
>Am I wrong?
>Traffic shaping is about ensuring the MAXIMUM limits are never violated in
>order to ensure that there is bandwidth available for critial data... but it
>doesn't ensure 100% channel saturation.
>I think.
You are quite correct in your reasoning. I tried my upload from work 
today, and could barely transfer at 30KB. A trace route showed a 140ms 
latency to my address. That would definatly explain that issue. But when 
trying that AIM direct connection, my latency to their 768k connection 
was under 40ms. With traffic shaping turned off, I could hit my max 
speed. With it on, I couldn't.

I've never seen the traffic shaper introduce enough latency to reduce my 
uploads while ping testing. Always stayed the same regardless of being 
on or off.

BTW, thanks for following up with me on this! It's very appreciated!