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From: Jan Ceuleers <jan.ceuleers@gmail.com>
To: bloat@lists.bufferbloat.net
Subject: Re: [Bloat] [aqm] the side effects of 330ms lag in the real world
Date: Wed, 30 Apr 2014 08:53:46 +0200	[thread overview]
Message-ID: <53609DFA.9040708@gmail.com> (raw)
In-Reply-To: <87bnvkkr2n.fsf@toke.dk>

On 04/29/2014 07:01 PM, Toke Høiland-Jørgensen wrote:
> However, as that graph shows, it is quite possible to completely avoid
> bufferbloat by deploying the right shaping. And in that case fibre
> *does* have a significant latency advantage. The best latency I've seen
> to the upstream gateway on DSL has been ~12 ms.

I am not an expert, but I believe that this is due to the use of
interleaving. This is a method to improve the strength of forward error
correction by spreading out the effects of impulse noise on DSL lines
across multiple reed-solomon-protected codewords at the expense of latency.

The topic is briefly discussed on the ADSL Wikipedia page.


  parent reply	other threads:[~2014-04-30  6:58 UTC|newest]

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-04-29  1:24 [Bloat] " Dave Taht
2014-04-29  7:08 ` [Bloat] [aqm] " Mikael Abrahamsson
2014-04-29  7:21   ` Fred Baker (fred)
2014-04-29  7:56     ` Mikael Abrahamsson
2014-04-29 15:46       ` Dave Taht
2014-04-29 16:51         ` Aaron Wood
2014-04-29 16:44       ` Jim Gettys
2014-04-29 16:57         ` Jim Gettys
2014-04-29 17:01         ` Toke Høiland-Jørgensen
2014-04-29 17:07           ` Jim Gettys
2014-04-29 18:09             ` Greg White
2014-04-30  3:21           ` Dave Taht
2014-04-30  6:53           ` Jan Ceuleers [this message]
2014-04-30  8:19             ` Pedro Tumusok
2014-04-30  8:30             ` Mikael Abrahamsson
2014-04-29 17:02         ` Dave Taht
2014-04-30  6:16         ` Mikael Abrahamsson
2014-04-29  7:43   ` Tristan Seligmann
2014-04-29 23:01 Hal Murray
2014-04-29 23:26 Michael Spacefalcon
2014-04-29 23:56 ` Steinar H. Gunderson
2014-04-30  0:14 ` Hal Murray

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