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bufferbloat videos are up.
From: Jim Gettys <jg () freedesktop org>
Date: Fri, 03 Feb 2012 14:29:00 -0500

If people have heard of bufferbloat at all, it is usually just an
abstraction despite having had personal experience with it. Bufferbloat
can occur in your operating system, your home router, your broadband
gear, wireless, and almost anywhere in the Internet. Most still think
that if experience poor Internet speed means they must need more
bandwidth, and take vast speed variation for granted. Sometimes, adding
bandwidth can actually hurt rather than help. Most people have no idea
what they can do about bufferbloat.

So I’ve been working to put together several demos to help make
bufferbloat concrete, and demonstrate at least partial mitigation. The
mitigation shown may or may not work in your home router, and you need
to be able to set both upload and download bandwidth. People like Fred
Baker, with fiber to his house and Cisco routers, need not pay attention....

Two of four cases we commonly all suffer from at home are:

 1. Broadband bufferbloat (upstream)
 2. Home router bufferbloat (downstream)

Rather than attempt to show worst case bufferbloat which can easily
induce complete failure, I decided to demonstrate these two cases of
“typical” bufferbloat as shown by the ICSI data. As the bufferbloat
varies widely as theICSI data
<http://gettys.files.wordpress.com/2010/12/uplink_buffer_all.png>shows
<http://gettys.files.wordpress.com/2010/12/downlink_buffer_all.png>,
your mileage will also vary widely.
There are two versions of the video:

 1. A short bufferbloat video
    <http://www.youtube.com/watch?v=npiG7EBzHOU>, of slightly over 8
    minutes, which includes both demonstrations, but elides most of the
    explanation. It’s intent is to get people “hooked” so they will want
    to know more.
 2. The longer version of the video
    <http://www.youtube.com/watch?v=-D-cJNtKwuw>clocks in at 21 minutes,
    includes both demonstrations, but gives a simplified explanation of
    bufferbloat’s cause, to encourage people to dig yet further.

Best regards,
Jim Gettys





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