[47655] in Cypherpunks
Why is blowfish so slow? Other fast algorithms?
daemon@ATHENA.MIT.EDU (David Mazieres)
Mon Jan 22 02:07:14 1996
Date: Mon, 22 Jan 1996 02:00:54 -0500
From: David Mazieres <dm@amsterdam.lcs.mit.edu>
To: cypherpunks@toad.com
First, can someone tell me if the latest version of blowfish (the one
in Applied Crypto 2nd edition) is available online somewhere? I
looked at a bunch of crypto ftp servers and could only find an older
version of blowfish that did not have the blf_ctx structure allowing
multiple keys to be active at a time.
More importantly, however, on a 120 MHz Pentium, the old blowfish
(compiled with gcc version 2.7.2 optimization -O6) seems to take about
12.6 microseconds for 1 M encryptions and decryptions, which works out
to about 95 cycles per byte. This is significantly more than the 26
cycles/byte number cited in Applied Crypto 2nd edition.
Can anyone suggest what I might do to speed this up?
Failing that, can anyone suggest other secure, preferably unpatented,
shared-key encryption algorithms that could encrypt at ethernet speeds
(1 MByte/sec) without using most of the CPU on a fast Pentium or
equivalent processor?
Thanks a lot,
David
