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From: Dan Siemon <dan@coverfire.com>
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Subject: Re: [Bloat] [Codel] [Cerowrt-devel] FQ_Codel lwn draft article
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On Mon, 2012-12-03 at 15:58 +0000, David Woodhouse wrote:
> ADSL is basically just ATM with a strange PHY. You have a bunch of
> options for how you use this ATM link. Mostly it's RFC2364 PPP-over-ATM
> or it's PPPoE on top of RFC2684 Ethernet-over-ATM.

Speaking of xDSL, does anyone on the list happen to have a good
understanding of how much per-packet overhead there is on VDSL2? I've
been tweaking the buffering and shaping on my upstream link and noticed
unexpected behavior with small packets.

The link below (use wayback machine version) has a good description of
per-packet overhead for various forms of ADSL but I haven't found
something similar for more modern DSL variants.
http://www.adsl-optimizer.dk/thesis/
http://web.archive.org/web/20090422131547/http://www.adsl-optimizer.dk/thesis/

I started a discussion on DSLReports
http://www.dslreports.com/forum/r27565251-Internet-Per-packet-overhead-on-Bell-s-VDSL-ATM-based-
but experimentally the overhead discussed there doesn't appear to be
correct
http://www.coverfire.com/archives/2012/11/29/per-packet-overhead-on-vdsl2/