From: Neil Davies <neil.davies@pnsol.com>
To: David Woodhouse <dwmw2@infradead.org>
Cc: codel@lists.bufferbloat.net, bloat <bloat@lists.bufferbloat.net>
Subject: Re: [Codel] [Bloat] The challenge
Date: Thu, 10 May 2012 16:34:53 +0100 [thread overview]
Message-ID: <F44A3240-6188-40A3-9B6E-DA09DBF68E22@pnsol.com> (raw)
In-Reply-To: <1336660932.27520.152.camel@shinybook.infradead.org>
Bit unfair to BT...
BT have architected their network so that cells loss doesn't happen.
They pace the cell rate, on a per line basis, in their BRASs so that
individual DSLAM buffers are not overrun.
The PPP sessions are terminated in BT's BRAS - the ISPs LNS establishes
an L2TP tunnel to the BRAS.
As for the sanity, we've measured other ISPs in the UK. They deliver consistently
more jitter and loss than BT's *wholesale* network.
Neil
On 10 May 2012, at 15:42, David Woodhouse wrote:
> On Thu, 2012-05-10 at 10:25 -0400, Justin McCann wrote:
>> Can't they turn on Early Packet Discard or something similar? This
>> seems like a no-brainer.
>
> This is British Telecom we're talking about.
>
> No, we cannot expect them to do *anything* even half sane.
>
> The ISP has clue, and the PPP session handled by BT's DSLAM is
> terminated in an L2TP session on their LNS. For the foreseeable future,
> that is where any queue management has to happen.
>
> --
> dwmw2
> _______________________________________________
> Bloat mailing list
> Bloat@lists.bufferbloat.net
> https://lists.bufferbloat.net/listinfo/bloat
next prev parent reply other threads:[~2012-05-10 15:35 UTC|newest]
Thread overview: 52+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-05-09 1:04 [Codel] " Dave Taht
2012-05-09 2:02 ` [Codel] [Bloat] " Kevin Gross
2012-05-09 3:13 ` [Codel] " Kathleen Nichols
2012-05-09 3:56 ` Dave Taht
2012-05-09 5:16 ` [Codel] [Bloat] " Simon Barber
2012-05-09 5:40 ` Eric Dumazet
2012-05-09 5:41 ` Dave Taht
2012-05-09 7:32 ` [Codel] [codel] some numbers on dual 10Gb links Eric Dumazet
2012-05-09 13:04 ` [Codel] [Bloat] The challenge Kevin Gross
2012-05-16 5:55 ` Jonathan Morton
2012-05-16 6:09 ` Eric Dumazet
2012-05-16 7:05 ` [Codel] Exploring the potential of codel, fq_codel, and qfq dave taht
2012-05-16 7:20 ` Dave Taht
2012-05-16 7:42 ` [Codel] [Bloat] " Eric Dumazet
2012-05-16 7:46 ` Eric Dumazet
2012-05-16 8:17 ` Eric Dumazet
2012-05-16 9:02 ` Jonathan Morton
2012-05-16 9:14 ` Eric Dumazet
2012-05-16 9:31 ` Jonathan Morton
2012-05-16 9:37 ` Eric Dumazet
2012-05-16 9:59 ` Jonathan Morton
2012-05-16 10:10 ` Eric Dumazet
2012-05-16 13:58 ` Eric Dumazet
2012-05-16 17:40 ` Rick Jones
2012-05-16 17:53 ` Eric Dumazet
2012-05-16 17:33 ` [Codel] " Rick Jones
2012-05-16 17:48 ` [Codel] [Bloat] " Eric Dumazet
2012-05-16 6:09 ` [Codel] [Bloat] The challenge Dave Taht
2012-05-16 6:31 ` Eric Dumazet
2012-05-16 8:15 ` Jonathan Morton
2012-05-09 19:10 ` Roger Jørgensen
2012-05-09 19:15 ` Dave Taht
2012-05-09 19:28 ` Dave Taht
2012-05-09 20:02 ` Simon Barber
2012-05-09 20:06 ` Fred Baker
2012-05-09 21:47 ` Jim Gettys
2012-05-09 23:58 ` Eric Dumazet
2012-05-10 2:34 ` Jonathan Morton
2012-05-10 2:37 ` Dave Taht
2012-05-10 6:35 ` David Woodhouse
2012-05-10 6:54 ` Jonathan Morton
2012-05-10 7:02 ` David Woodhouse
2012-05-10 14:25 ` Justin McCann
2012-05-10 14:42 ` David Woodhouse
2012-05-10 15:34 ` Neil Davies [this message]
2012-05-10 21:20 ` Jim Gettys
2012-05-14 7:27 ` Jonathan Morton
2012-05-14 7:34 ` Eric Dumazet
2012-05-14 13:55 ` David Woodhouse
2012-05-18 20:56 ` [Codel] [Bloat] Linux-able modems Jonathan Morton
2012-05-18 21:36 ` Dave Taht
2012-05-18 22:34 ` Dave Taht
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