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Re: [aqm] [iccrg] [tcpm] ECN support and usage on the Internet

Matthew Ford <ford@isoc.org> Wed, 20 March 2013 11:14 UTC

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From: Matthew Ford <ford@isoc.org>
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Date: Wed, 20 Mar 2013 11:14:42 +0000
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To: Jim Gettys <jg@freedesktop.org>
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Subject: Re: [aqm] [iccrg] [tcpm] ECN support and usage on the Internet
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(trimmed the cc list)

On 19 Mar 2013, at 22:36, Jim Gettys <jg@freedesktop.org> wrote:

> There is one other issue with ECN: when operating at low bandwidth at the very edge of the net, it can still be advantageous to drop a packet rather than ECN mark it, to get back the transmission time of the packet.  Dave Taht's experiments (IIRC) were below 4Mbps for this advantage (when doing VOIP over that bottleneck competing against other traffic in a best effort class).

Hmmm. According to Akamai, global average connection speeds remain stubbornly below 4Mbps [1], so if Dave's analysis is correct, an unsophisticated ECN-deployment campaign may be counterproductive.

Mat

[1] http://www.internetsociety.org/blog/2013/02/internet-connection-speeds-and-right-some

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