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Date: Mon, 18 Dec 2000 03:49:44 -0500
To: Karel Kulhavy <clock@atrey.karlin.mff.cuni.cz>
From: David Feuer <David_Feuer@brown.edu>
Subject: Re: /dev/random: really secure?
Cc: linux-kernel@vger.kernel.org
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At 09:21 AM 12/18/2000 +0100, Karel Kulhavy wrote:
> >       There are hidden sources of entropy. One is clock skew between 
> the keyboard
> > processor's clock, the keyboard controller's clock, and the CPU clock
> > generator's PLL. Another is data motion between the CPU cache and main
>
>In the RFC 1750, they write it is not recommended to rely on computer 
>clocks to
>generate random. Isn't it this case?

This is the case, but the important thing that David Schwartz said is that 
it does not rely on the time in a clock, but rather on the pretty much 
completely random skew between several independent clocks.  Any particular 
oscillator will vary in speed semi-randomly, and if you compare multiple 
clocks you can get pretty random numbers.

--
This message has been brought to you by the letter alpha and the number pi.
Open Source: Think locally; act globally.
David Feuer
David_Feuer@brown.edu

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