Exactly. More or less by definition, since NATs and firewalls hide
stuff, we can't possibly measure the stuff they hide.
And since they are hiding stuff for good reason, administrators
more or less by definition will not answer accurately. So it can't
be measured.
My hand waving estimate is that 40% (160M) of users are behind a firewall
and/or NAT, 50% (200M) on dial-up, and 10% (40M) have direct always-on access.
But there is no way I can justify these numbers.
Brian
Paul Hoffman / IMC wrote:
At 12:10 PM -0500 1/23/01, Frank Solensky wrote:
One could ask a sample of administrators and extrapolate the results
but, again, the problem becomes how confident you could be of the
results if you don't get a very significant response rate
The problem is *much* worse than that. You have to be confident that
your sampling method actually reflects enough of the Internet to be
valid. Determining how you have reached a valid sample of
administrators would be an interesting problem. Further, it is safe
to assume that administrators for the largest networks are the least
likely to reply, or to reply accurately.
And then there is the problem of assuming that they understand your
question, and can even count the systems on their networks well
enough to answer accurately...
--Paul Hoffman, Director
--Internet Mail Consortium