chip-level randomness?

[Bram Cohen]

On Wed, 19 Sep 2001, Peter Fairbrother wrote:

> Bram Cohen wrote:
> 
> > You only have to do it once at startup to get enough entropy in there.
> 
> If your machine is left on for months or years the seed entropy would become
> a big target. If your PRNG status is compromised then all future uses of
> PRNG output are compromised, which means pretty much everything crypto.
> Other attacks on the PRNG become possible.

Such attacks can be stopped by reseeding once a minute or so, at much less
computational cost than doing it 'continuously'. I think periodic
reseedings are worth doing, even though I've never actually heard of an
attack on the internal state of a PRNG which was launched *after* it had
been seeded properly once already.

-Bram Cohen

"Markets can remain irrational longer than you can remain solvent"
                                        -- John Maynard Keynes




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