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From: "Folkert van Heusden" <folkert@vanheusden.com>
To: "'John Bradford'" <john@grabjohn.com>
Cc: <linux-kernel@vger.kernel.org>
Subject: RE: Want a random entropy source?
Date: Sat, 28 Dec 2002 21:53:17 +0100
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> Well, the 50hz from the mains isn't a perfect 50hz; it has random (yes)
> fluctuations.
JB> Yes, that's true.
JB> More generally, though, is there any point in this going in to the
JB> mainline kernel, if:
JB> * Most users don't need faster entropy generation than we've got
JB> and
JB> * The entropy gathered from the soundcard is statistically inferior to
JB> that gathered from the current sources of entropy.

Well, there isn't any :o) That's why there's a user-level implementation
for such a beast for those who do need it.
( http://www.vanheusden.com/mirrors/audio-entropyd-0.0.5.tgz )

JB> I don't see how it's possible to guarantee that the data below a
JB> certain dB level from the soundcard is noise.

Some guy contacted me about audio-entropyd and told me he'd done a lot
of analysis on all how this and gave me a few hints how to improve the
quality of what is produced with this tool. A quick fourier-
transformation doesn't really show any peaks.

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