From: Jonathan Morton <chromatix99@gmail.com>
To: David Lang <david@lang.hm>
Cc: Benjamin Cronce <bcronce@gmail.com>, bloat <bloat@lists.bufferbloat.net>
Subject: Re: [Bloat] benefits of ack filtering
Date: Wed, 13 Dec 2017 00:41:44 +0200 [thread overview]
Message-ID: <CAJq5cE3MwtYWSWHwNJySzmJ9j0Yc3y4qB6o7GMSSsiuCqGW8TA@mail.gmail.com> (raw)
In-Reply-To: <CAJq5cE3nfSQP0GCLjp=X0T-iHHgAs=YUCcr34e3ARgkrGZe-wg@mail.gmail.com>
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Actually, the cost argument goes the other way. You need heavy DSP to
*receive* high bandwidths; sending it is much easier computationally.
Also, in aggregate a hundred cheap CPE boxes probably have more DSP
horsepower than the one head-end box serving them.
What the centralised head-end has an advantage in is transmit power, and
thus SNR. This feeds into Shannon's equation and supports your argument
more directly. In ADSL this is partly compensated for by assigning the
lower frequency carriers to the upload direction, since they have less loss
than high frequencies on a copper pair.
However, in the most extreme examples I've seen, the level of asymmetry has
little to do with the underlying link technology and more to do with how
the provisioning was arbitrarily set up.
Things like ADSL with an unrestricted downlink sync rate but uplink limited
to 128k. Or DOCSIS with a huge headline bandwidth for downlink, and no
obvious mention (until you've paid for it, set it up and measured it) that
the uplink shaper is set to about a fiftieth of that. I seriously doubt
that DOCSIS is ever inherently that asymmetric.
- Jonathan Morton
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next prev parent reply other threads:[~2017-12-12 22:41 UTC|newest]
Thread overview: 76+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-11-28 21:48 Dave Taht
2017-11-29 6:09 ` Mikael Abrahamsson
2017-11-29 9:34 ` Sebastian Moeller
2017-11-29 12:49 ` Mikael Abrahamsson
2017-11-29 13:13 ` Luca Muscariello
2017-11-29 14:31 ` Mikael Abrahamsson
2017-11-29 14:36 ` Jonathan Morton
2017-11-29 15:24 ` Andrés Arcia-Moret
2017-11-29 15:53 ` Luca Muscariello
[not found] ` <CAJq5cE3qsmy8EFYZmQsLL_frm8Tty9Gkm92MQPZ649+kpM1oMw@mail.gmail.com>
2017-11-29 16:13 ` Jonathan Morton
2017-11-30 7:03 ` Michael Welzl
2017-11-30 7:24 ` Dave Taht
2017-11-30 7:45 ` Dave Taht
2017-11-30 7:48 ` Jonathan Morton
2017-11-30 8:00 ` Luca Muscariello
2017-11-30 10:24 ` Eric Dumazet
2017-11-30 13:04 ` Mikael Abrahamsson
2017-11-30 15:51 ` Eric Dumazet
2017-12-01 0:28 ` David Lang
2017-12-01 7:09 ` Jan Ceuleers
2017-12-01 12:53 ` Toke Høiland-Jørgensen
2017-12-01 13:13 ` [Bloat] [Make-wifi-fast] " Кирилл Луконин
2017-12-01 13:22 ` Luca Muscariello
2017-12-11 17:42 ` Simon Barber
2017-12-01 13:17 ` [Bloat] " Luca Muscariello
2017-12-01 13:40 ` Toke Høiland-Jørgensen
2017-12-01 17:42 ` Dave Taht
2017-12-01 20:39 ` Juliusz Chroboczek
2017-12-03 5:20 ` [Bloat] [Make-wifi-fast] " Bob McMahon
2017-12-03 10:35 ` Juliusz Chroboczek
2017-12-03 11:40 ` Jan Ceuleers
2017-12-03 13:57 ` Juliusz Chroboczek
2017-12-03 14:07 ` Mikael Abrahamsson
2017-12-03 19:53 ` Juliusz Chroboczek
2017-12-03 14:09 ` Ryan Mounce
2017-12-03 19:54 ` Juliusz Chroboczek
2017-12-03 20:14 ` Sebastian Moeller
2017-12-03 22:27 ` Dave Taht
2017-12-03 15:25 ` Robert Bradley
2017-12-04 3:44 ` Dave Taht
2017-12-04 14:38 ` David Collier-Brown
2017-12-04 15:44 ` Juliusz Chroboczek
2017-12-04 17:17 ` David Collier-Brown
2017-12-03 19:04 ` Bob McMahon
2017-12-01 21:17 ` Bob McMahon
2017-12-01 8:45 ` [Bloat] " Sebastian Moeller
2017-12-01 10:45 ` Luca Muscariello
2017-12-01 18:43 ` Dave Taht
2017-12-01 18:57 ` Luca Muscariello
2017-12-01 19:36 ` Dave Taht
2017-11-30 14:51 ` Neal Cardwell
2017-11-30 15:55 ` Eric Dumazet
2017-11-30 15:57 ` Neal Cardwell
2017-11-29 16:50 ` Sebastian Moeller
2017-12-12 19:27 ` Benjamin Cronce
2017-12-12 20:04 ` Dave Taht
2017-12-12 21:03 ` David Lang
2017-12-12 21:29 ` Jonathan Morton
2017-12-12 22:03 ` Jonathan Morton
2017-12-12 22:21 ` David Lang
[not found] ` <CAJq5cE3nfSQP0GCLjp=X0T-iHHgAs=YUCcr34e3ARgkrGZe-wg@mail.gmail.com>
2017-12-12 22:41 ` Jonathan Morton [this message]
2017-12-13 9:46 ` Mikael Abrahamsson
2017-12-13 10:03 ` Jonathan Morton
2017-12-13 12:11 ` Sebastian Moeller
2017-12-13 12:18 ` Jonathan Morton
2017-12-13 12:36 ` Sebastian Moeller
2017-12-13 12:39 ` Luca Muscariello
2017-11-29 18:21 ` Juliusz Chroboczek
2017-11-29 18:41 ` Dave Taht
2017-11-29 23:29 ` Steinar H. Gunderson
2017-11-29 23:59 ` Stephen Hemminger
2017-11-30 0:21 ` Eric Dumazet
2017-12-11 20:15 ` Benjamin Cronce
2017-11-29 18:28 ` Juliusz Chroboczek
2017-11-29 18:48 ` Dave Taht
2017-12-11 18:30 ` Jonathan Morton
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