From: pmetzger@shearson.com (Perry E. Metzger)
Date: Wed, 11 Nov 92 09:08:59 PST
To: hughes@soda.berkeley.edu
Subject: Random number generators
In-Reply-To: <9211111624.AA08843@soda.berkeley.edu>
Message-ID: <9211111657.AA13574@newsu.shearson.com>
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>From: Eric Hughes <hughes@soda.berkeley.edu>

>There seems to be some confusion over this random number device.

>Perry Metzger forwarded me some information about Newbridge
>Microsystems and the part number of a chip that made random numbers.
>At the crypto BOF at hackers I mentioned that there was a need for a
>hardware random number generator and that I knew of some chip to do
>it.  John Draper, who was there, expressed a desire to work on such a
>device.  I forwarded him the information about the chip.

>What I didn't know was the cost or design of this chip.  It appears to
>use a radioactive source to make random numbers.  This may account for
>the cost.  In any case, it is likely that most applications don't need
>this kind of chip.

Just for the record...
As the data sheet makes clear, it most certainly DOES NOT use a
radioactive source. Its very hard to get 20kbits/sec of random numbers
reliably out of any radioactive source you are going to want to be
near, anyway. It operates off of thermal noise just like virtually
every other such device.

It should be possible to build a similar device out of ordinary
discrete components without overwhelming difficulty. The only problem
would be to make sure that the output was reliably random, and not
overly dependant on things like temperature.

Perry