[29888] in cryptography@c2.net mail archive
Re: Quantum RNG
daemon@ATHENA.MIT.EDU (James A. Donald)
Thu Jul 6 16:18:21 2006
X-Original-To: cryptography@metzdowd.com
X-Original-To: cryptography@metzdowd.com
Date: Thu, 06 Jul 2006 14:03:11 +1000
From: "James A. Donald" <jamesd@echeque.com>
To: John Denker <jsd@av8n.com>
Cc: Andrea Pasquinucci <cesare@ucci.it>, cryptography@metzdowd.com
In-Reply-To: <44AA9E77.9040000@av8n.com>
--
John Denker wrote:
> Quantum processes are in some very narrow theoretical
> sense more "fundamentally" random than other sources
> of randomness, such as thermal noise ... but they are
> not better in any practical sense.
>
> The basic quantum process is less sensitive to
> temperature than a purely thermal process ... but
> temperature dependence is easily accounted for in any
> practical situation, and -- more importantly -- there
> are all sorts of other practical considerations (such
> as detector dead-time issues) that make real quantum
> detectors far from ideal.
>
> The devil is in the details, and obtaining the raw
> data from a quantum process is nowhere near necessary
> and nowhere near sufficient to make a good randomness
> generator.
And if you want to obtain noise from quantum
indeterminacy, shot noise is much more convenient.
Instead of photons going through a half silvered mirror,
and randomly being reflected or not, you rely on
electrons randomly winding up at the base or the
collector of a transistor.
--digsig
James A. Donald
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/KNHHNPZ6iBsO6gvfPyHJxLKSHaisGIVaOLrrfDv
4uxfFO8C/uuRkbz3u2rG4U8fpFKfzj+zr6czKsf69
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