Re: Final (?) Draft of Press Release

Justin Dolske (dolske@cis.ohio-state.edu)
Thu, 3 Apr 1997 16:01:12 -0500 (EST)


On Wed, 2 Apr 1997, C Matthew Curtin wrote:

> for a needle in a proverbial haystack. The "needle" is the
> cryptographic key used to encrypt a given message, and the
> "haystack" is the huge pile of possible keys: 72,057,594,037,927,936
> (that's over 72 quadrillion) of them.

Just for kicks, and go possibly give people a sense of scale:

Assuming a single piece of hay (straw? :) is a 10cm long, .2 cm wide
cylinder, and they're all packed fairly tightly together...

V_haystack = (2**56) * 10cm * pi * .01cm
= (2**56) * .311415926
= 22,637,560,806,492,498 cm^3

given that V_sphere = 4/3 * pi * r**3...
[haystacks are not spheres, but we'll assume it's a half-sphere by
doubling the volume]
r_haystack = 2.21km
= 1.37 miles

So, we're looking for a needle in a haystack over 2.5 miles wide, 1 mile
high. :-)

Hmm. Given that I've done about 5% of the .2% we've searched (I think),
I've searched through a haystack about 230 yards wide, 115 yards high.

*looks out the window towards OSU's football stadium*

Yikes! That's big!

Hmm. So a client searching 100,000 keys/sec is searching through a cube of
hay about 1 foot/side every second.

Have I carried this analogy too far? :-)

Justin Dolske <URL:http://www.cis.ohio-state.edu/~dolske/>
(dolske@cis.ohio-state.edu)
Graduate Fellow / Research Associate at The Ohio State University, CIS Dept.
-=-=-=-=-=-=-=-=-=-=-=-=-=- Random Sig-o-Matic (tm) -=-=-=-=-=-=-=-=-=-=-=-=-
". . . my purpose is not to examine all the possibilities. My purpose is to
create strife and controversy for no reason." Dave Barry