Network integrity and non-random removal of nodes
sgorman1 at gmu.edu
sgorman1 at gmu.edu
Thu Nov 21 19:00:03 UTC 2002
It still depends on the network that you are using for analysis.
Assuming the paper uses the same dataset as the link Sean provided the
giant cluster they are analyzing is only 8.3% of IP nodes in their
sample. It takes the removal of 25% when only looking at that small
densely connected section, it says nothing about what will happen to the
other 91.7% of nodes. Considering that 55% of the remaining nodes are
trees, they will be saying "Houston we have a problem" well before 25%.
Whether or not it matters that they have a problem in an entirely
different question. I've probably kicked this dead horse enough already
----- Original Message -----
From: William Waites <ww at styx.org>
Date: Thursday, November 21, 2002 6:31 pm
Subject: Re: Network integrity and non-random removal of nodes
>
> >>> "Sean" == Sean Donelan <sean at donelan.com> writes:
>
> Sean> On 20 Nov 2002, William Waites wrote:
> >> If you randomly select nodes to remove, by the time you have
> >> removed 25% of them, the network breaks up into many isolated
> >> islands.
>
> Sean> One of the key points was the nodes were removed in ranked
> Sean> order, not in random order.
>
> I stand corrected.
>
> It would be interesting to see what outdegree looks like as a function
> of rank -- in the paper they give only the maximum and average
> (geo. mean) outdegrees. Is there also a critical point 25% of the way
> through the ranking? Probably not or one would expect they'd have
> mentioned it...
>
> So then the 12500 *biggest* routers have to be disabled before the
> graph breaks into many islands. This would be yet harder
> from an
> attacker's point of view, no?
>
> -w
>
>
>
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