From: gtoal@an-teallach.com (Graham Toal)
Date: Wed, 1 Dec 93 11:38:14 PST
To: cypherpunks@toad.com
Subject: Cryptosplit 2.0
Message-ID: <11678@an-teallach.com>
MIME-Version: 1.0
Content-Type: text/plain


In article <9311291648.AA25233@jobe.shell.portal.com>
           hfinney@shell.portal.com "Hal Finney" writes:
 > I once proposed a DOS TSR (a "background" program) which would monitor
 > your keystrokes all day long and condense the timing data into a file
 > full of random bits.  Then you'd use up the bits when you needed to do
 > cryptography.  I haven't learned enough about DOS to write such a
 > thing, though.

I'm doing this for unix this weekend.  One very important point to
note:  only take *one* bit of random data per keystroke, and take
it by ex-oring every single bit in the clock() value - that way you
make sure the randomly fluctuating one is in there - because on
some systems the bottom bit might always be 0, if the resolution
of the clock is low.  Also, think about the problems if you have
a function that returns milliseconds but the hardware clock is one
tick, say, every 1/17 sec...

G
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