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From: =?utf-8?Q?Toke_H=C3=B8iland-J=C3=B8rgensen?= <toke@toke.dk>
To: Paolo Valente <paolo.valente@unimore.it>
References: <D2F2013B-D7FC-4F7E-9C3C-8148BC9935C8@unimore.it>
Date: Mon, 27 Apr 2015 11:57:40 +0200
In-Reply-To: <D2F2013B-D7FC-4F7E-9C3C-8148BC9935C8@unimore.it> (Paolo
	Valente's message of "Mon, 27 Apr 2015 11:48:44 +0200")
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Cc: bloat <bloat@lists.bufferbloat.net>
Subject: Re: [Bloat] Detecting bufferbloat from outside a node
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Paolo Valente <paolo.valente@unimore.it> writes:

> a network-monitoring company got curious about bufferbloat issues and
> asked me to investigate a little bit the following issue (quite
> interesting in my opinion). Is it possible to detect, from outside a
> node, if the node is bufferbloated? In particular, the only action
> allowed would be to observe the packets entering and leaving the node
> (plus, of course, their timing).

Sure. Just measure the timing when the network is unloaded and compare
it to when it is loaded to capacity. We do that all the time.

The details of course depend on what you define by a 'node', what role
it plays in the network (does it forward or originate packets?), and
what control you have over the traffic flowing through it. :)

-Toke