Greg> But is still would be
Greg> interesting to know: if I were to go buy a machine today,
Greg> specifically to do deschall, how would I get the most bang for
Greg> my buck?
Not a general purpose computer of any type. Despite the fact that we
were able to get pretty amazing speeds through a combination of
Darrell's bitslicing and Rocke's S-box constructions, the speed that
we got would pale by comparison to hardware implementations.
FPGA stuff can be had pretty cheaply; it wouldn't be a big deal for
someone to get ahold of one and wire it for DES. I don't have recent
calculations available, but we could probably search the keyspace in a
few weeks by throwing a few hundred thousand dollars' worth of
hardware at it. Spending even more money, it could be reduced
further. The figure $300 million has been noted a few times in what
it would cost to recover DES keys in a few seconds each.
While it is certainly silly to spend that much money to find the
contents of one message, such a machine would be able to find the
contents of _any_ message encrypted with DES very quickly. Find
enough customers who will pay for this service, and such a large
expenditure suddenly seems more and more feasible...
-- Matt Curtin Chief Scientist Megasoft Online cmcurtin@research.megasoft.com http://www.research.megasoft.com/people/cmcurtin/ I speak only for myself Pull AGIS.NET's plug! Crack DES NOW! http://www.frii.com/~rcv/deschall.htm