Network integrity and non-random removal of nodes
sgorman1 at gmu.edu
sgorman1 at gmu.edu
Thu Nov 21 19:30:07 UTC 2002
> The supposition would be that the remaining nodes are evenly
> distributed around the core so the percentage of nodes outside of the
> core without connectivity should be roughly the same as the percentage
> of nodes removed from the core. At least until the core goes
> non-linear...
Is that the supposition stated in the paper? The reason being it
contradicts quite a bit of similar research. Nodes inside and outside
of the core do not typically disconnect at the same rate. Think of it
this way, if a big well connected node goes down the other big conencted
nodes in the core are likely to have an alternate connection to
compensate for the link loss. Average distance might go up a little
bit, but that is about it. The nodes outside of the core on the other
hand are much more sparsely connected. 55% of them are trees meaning
that they only have one connection. There is no back up link, so if
their big hub node goes down they are out of commission. Hence you
could have large numbers of nodes outside the core disconencted before
you would see any effect inside the core. By the time the core goes
non-linear the periphery is gonna be long gone and disconnected.
----- Original Message -----
From: William Waites <ww at styx.org>
Date: Thursday, November 21, 2002 7:14 pm
Subject: Re: Network integrity and non-random removal of nodes
> >>> "Sean" == <sgorman1 at gmu.edu> writes:
>
> Sean> it says nothing about what will happen to the other
> 91.7% of
> Sean> nodes. Considering that 55% of the remaining nodes are
> Sean> trees, they will be saying "Houston we have a problem" well
> Sean> before 25%.
>
> The supposition would be that the remaining nodes are evenly
> distributed around the core so the percentage of nodes outside of the
> core without connectivity should be roughly the same as the percentage
> of nodes removed from the core. At least until the core goes
> non-linear...
>
> >> 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...
>
> It turns out that this is buried in one of the graphs (fig. 6) and
> does not appear to have any special properties 25% of the way through.
> It does have an inflection point around the 1000th node or so (2.5%).
>
> -w
>
>
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