From owner-freebsd-ipfw@FreeBSD.ORG  Wed Nov 13 02:35:36 2013
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Date: Tue, 12 Nov 2013 18:35:35 -0800
Message-ID: <CAL_s3F5Hx0XJ8Nct=urWGN72hrGQ2LT2nJfG3OxgWT5oxtjW9Q@mail.gmail.com>
Subject: Bursty data transfer with Dummynet
From: Ahmed Hamza <ahmed.hmz@gmail.com>
To: freebsd-ipfw@freebsd.org
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Hi All,

I'm trying to use Dummynet to test the behaviour of my video streaming
application in various network conditions. Dummynet was compiled and
installed on an Ubuntu 12.04 box with a 2.6 Linux kernel. I'm
experiencing a strange behaviour when I reduce the bandwidth of the
link/path.

For some reason, instead of having a slow download speed. It seems as
if the download is happening in bursts! A portion of the data is
downloaded at a high speed, then the data transfer stops for a period
of time and then resumes again (and so on). Does anyone have an idea
what could be the cause? Or is this even an expected behaviour? If so,
why?

Thanks,
-Ahmed