Re: randomdev entropy gathering is really weak

[Peter Dufault]

> In message <[EMAIL PROTECTED]> Peter Dufault writes:
> : > The reason why ntp is interesting is that we compare the received data
> : > with our unpredictable local clock.  It is the result of this comparison
> : > which is good entropy bits.
> : 
> : Is the resolution of thermal sensors on many new motherboards and
> : CPU high enough to get thermal randomness?
> 
> Yes.  You'll also find that the voltage drifts as well.  However, I
> doubt you'd be able to get more than 1 bit out of the voltage
> readings.  The thermal readings, depending on their precision, would
> also yield several random bits.  But this several may be only 3 or 4.
> The temperature varies based on work load and on the climate controls
> in place at the site.

I actually meant can you get real randomness,
measuring the thermal noise in the on-chip temperature diode
should be a good source of randomness.  Except they are probably "kind"
enough to fully filter it out.

Peter

--

Peter Dufault ([EMAIL PROTECTED])   Realtime development, Machine control,
HD Associates, Inc.               Fail-Safe systems, Agency approval


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