Re: TRNG with 18 Mbit/s using Thermal Noise

On Sun, 11 Jan 2009 21:07:29 -0600, rpw3@xxxxxxxx (Rob Warnock) wrote:

Jo Schueth <jo@xxxxxxxxxxxxx> wrote:
+---------------
| in a home-brew project, I recently built a TRNG based on thermal noise
| that achieves a net data rate of 18 MBit/s after post-processing.
...
| http://www.schlaupelz.de/TRNG/Highspeed_TRNG.html
|
| The point is not that you can build a TRNG with good quality output
| from readily available parts at home, but rather the high bandwith
| achieved with this design. ...
+---------------

Congratulations! It's always rewarding to build something and get
it working.

I would just note, however, that since you already have a comparator
and at Atmel micro board, I don't see why you really need the
additional complexity of the LNB & antenna. A standard microwave
noise diode (of the sort used to calibrate pwoer meters) connected
to your comparator (possibly with a cheap op-amp pre-amp stage)
should give you thermal noise every bit as fast & good as your
LNB+antenna, but mountable right on your Atmel board.

Or if you're willing to settle for Zener noise a.k.a. avalanche noise
(*almost* as good as thermal, for RNGs at least), then you might want
to consider one of these approaches:

http://world.std.com/~reinhold/waynesrngcomp.gif
http://www.maxim-ic.com/appnotes.cfm/appnote_number/3469
http://willware.net/hw-rng.html
http://www.cryogenius.com/hardware/rng/
http://www.cryogenius.com/hardware/isarng/
http://www.ciphersbyritter.com/NOISE/NOISRC.HTM
http://electronicdesign.com/Files/29/6356/Figure_01.gif

You would, of course, need to do de-biasing (Von Neuman or eq.)
and whitening (SHA-1 or eq., perhaps), but you need that anyway
for your LNB+antenna design...


-Rob
I would add http://www.av8n.com/turbid/paper/turbid.htm to that list.

rossum

.

Relevant Pages

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  • Re: TRNG with 18 Mbit/s using Thermal Noise
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