Re: [conex] Potentially interesting ConEx problem

Bob Briscoe <> Tue, 05 March 2013 09:53 UTC

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Date: Tue, 05 Mar 2013 09:53:12 +0000
To: Matt Mathis <>
From: Bob Briscoe <>
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Subject: Re: [conex] Potentially interesting ConEx problem
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The solution to the access link part of this problem is explained in:

It can only distinguish access link congestion from shared 
congestion. Distinguishing home network congestion is harder, but 
possible with a tunnel to the home router, which already exists in 
some DSL arrangements (e.g. in BT we use a tunnel for services that 
share a line).


At 22:18 04/03/2013, Matt Mathis wrote:
>I have an interesting problem that I wish ConEx could solve, but I
>don't see how.   I want to distinguish between congestion on the path
>between a server and a subscriber aggregation point (e.g. DSLAM etc)
>and congestion beyond the aggregation point (e.g. the access links
>themselves, or the user's home network).
>There are some ways to infer this, but as far as I can tell there is
>not a reasonable way to measure it directly.   This is a problem that
>we have touched on in the past, but I don't recall discussing any
>The best way to predict the future is to create it.  - Alan Kay
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Bob Briscoe,                                                  BT