Re: Distributed DES crack

[Matt Blaze <mab@crypto.com>]

> On Tue, 23 Jul 1996, Matt Blaze wrote:
> 
> <snip>
> > 
> > Personally, I'd rather someone finish up the Wiener ASIC to the point where
> > it could go out to fab, get some prototype chips made, design a board around
> > it, and publish the design, from board layout on down.  This would be a
> > great Master's project, and some of us (maybe me, but I'll have to check)
> > might even be able to scrape up enough funds to buy enough chips/boards/etc
> > to build a modest size machine (say, that could exhaust a DES key in 1-6
> > months).  Initial engineering costs aside, the marginal cost of each
> > such machine could be well within the budgets of, say, a medium size crypto
> > research lab, and would make a scary enough demo to convince even the
> > most trusting management types of the risks of 56 bit keys.
> > alerts me to an interesting topic.  Thanks.)
> 
> Matt, can you give us an idea of the cost of a "modest size machine" might
> be?  Is this something we can do with a C'punks bake sale or our we going
> to need corporate/academic support?  Also, if we do use the bake sale
> approach, is there some way the money can be collected and routed into an
> R&D sort of facility without causing a lot of stink with whomever actually
> runs the place, like a university?

My estimate is that an FPGA-based machine that can do a single DES key
every four months (eight months to exhaust the whole keyspace) could
be built with off-the-shelf stuff for comfortably under $50k (plus
labor, plus software development costs).  A prototype board should cost
under $1000 and will help prove the concept and get a more accurate cost
estimate.  I expect to build such a prototype machine myself, and, if it
works as I expect, maybe the whole thing.

-matt