Re: Waiting for Randot (or: nia and maya were right and I was wrong)

[Thor Lancelot Simon <tls%panix.com@localhost>]

On Fri, Jan 15, 2021 at 12:21:24AM +0000, Taylor R Campbell wrote:
> 
> What about them?  Systems without usable microphone noise are no worse
> off than they would have been without nia's suggestion.

There are actually a couple of things that can be done here.

1) It's likely better to max out the gain on a _disconnected_ audio input
   so you're getting mostly amplifier noise than to use real ambient audio.

2) Some audio devices have their own clocks not derived from the system clock.
   This clock can be sampled against the system clock to construct a
   clock-skew entropy source.

I think either of these is best done in the hardware device driver itself;
but honestly, it's hard to knock the simplicity of the quick and dirty
approaches that do it all in userspace.

Thor