[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: fast 386 DES code figures
What still bugs me is that Schneier lists the speed of one
commercial DES implementation as 40,600 encryptions/sec on a
33 Mhz 486. I just don't see how that's possible without
using a lot more memory for lookup table space (I use only 2K,
which is nice in a DOS environment).
Well, yes -- you can use a lot more table space. In particular, you
can compose the S and P boxes. Or maybe it does run in 32 bit mode;
Schneier's table imlies that it does. Or maybe a branch-free
implementation is the wrong strategy, since it could mean that you
aren't executing out of the instruction cache.
Follow-Ups: