Re: [Bloat] Usage Based Billing - It's All About Perceived Congestion

[Steve Bauer <s_bauer@alum.mit.edu>]

On Mon, Feb 28, 2011 at 4:56 PM, richard <richard@pacdat.net> wrote:
> The result is:
> http://digital-rag.com/article.php/All-About-Perceived-Congestion-UBB
> It's aimed at the public and non-technical so allow me a few missing
> things in the explanations :)

Hi Richard,

You recommended to your readers:

"You want to bug your ISP to turn off any/all "helper" buffering in
your modem that purports to "increase upload speed for short periods"
since this is buffering and part of the problem."

I am assuming you intended that to apply to Powerboost.  Based upon my
understanding of various implementations of Powerboost,
turning it off would *not* help with latency under load simply
because the buffer sizes are fixed in today's cable modems.

So these issues are orthogonal.  There are certainly
problems, but turning off Powerboost isn't part of the fix.

Indeed, turning Powerboost off could make the problem worse. A
buffer that would otherwise have drained if Powerboost was in effect,
would be more likely to have a queue of packets sitting in it adding
additional latency to later arrivals.  Again, my key assumption is
that disabling Powerboost simply doesn't change the buffer size.

As always, happy to be proved wrong.  :-)

Thanks,
Steve Bauer
MIT