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@styx.org> Date: Thursday, November 21, 2002 6:31 pm Subject: Re: Network integrity and non-random removal of nodes
"Sean" == Sean Donelan <sean@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