New entropy source proposal.

Ivan Voras ivoras at
Mon Mar 7 21:45:32 GMT 2005

Pawel Jakub Dawidek wrote:

> +> Er, not very random.
> Are you sure you used /dev/dspW? It give me really good results with my
> sound card.

Sound card noise REALLY depends on the type and age of the said
hardware. In a good soundcard (traditionally, Creative Sound Blaster or
whatever they're calling it now), the noise is fairly minimal to
nonexistant (I'm saying this purely as as a user/listener, not RNG
expert), while on mass-market hardware such as various AC97 cards,
especially if older or embedded into notebooks, the noise is very apparent.

It's also very annoying that DA hardware picks up various inteferences
from surrounding buses - on many low end system moving a mouse, resizing
windows or accessing disk drives will produce bursts of audiable noise.

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