H. Peter Anvin wrote:
> However, those aren't the main failure modes you need to be concerned
> with. Antenna effects may actually be your biggest problem -- picking
> up deterministic signals from other parts of the system.
David Wagner wrote:
> For instance, is there a risk that the audio data you read is strongly
> correlated to 60Hz mains noise in some scenarios? ...
I don't think predictable elements in the audio hurt anything.
So long as there is a noise component, things are fine.
Take the case of a half-full-scale 60 Hz sine wave plus a tiny
bit of noise. No problem---each sample would still be worth
0.1 bit because the attacker can only guess the 60 Hz part:
subtract this out and you've still got unpredictable noise.
Same deal with crosstalk between channels, so long as it's
reasonably small, say -20 dB or better (as it will be with any
sane sound chip).
> [ audio-entropyd ]
Aha, nothing new under the sun.
Cheers,
Peter Monta
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This archive was generated by hypermail 2b29 : Thu Feb 07 2002 - 21:00:20 EST