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Comment by JKCalhoun | Hacker News Reader

For simple electronics circuits, reverse-biasing a transistor past its breakdown voltage will give you "noise" — an ADC will give you random values.

I don't know how statistically random it is — suspect it is quantum in nature though since we're dealing with transistors.

(EDIT: checked with ChatGPT, has a sense of humor: "Be careful not to exceed the maximum reverse voltage ratings, or you’ll get more “magic smoke” than white noise.")

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Most any sensor attached to a realworld physical system can produce sufficient randomness. Put a vibration sensor on my clothes dryer, plug the output into an md5 hash, and voila. Or setup a webcam aimed at a tree blowing in a breeze. Or pour out some m&ms onto a table and photograph that. We dont need to go quantum when sufficiently random systems like turbulance exist in the macro world.

Insert ref about Github's lava lamps

https://web.archive.org/web/20010926211816/http://lavarand.o... 6 years prior to github, and the claim is 1996 on that link there, which is 12 years prior to github.

not denigrating, just pointing out that the "idea" was around before then, and i can't remember where i first saw it.

I don't know about the age of this Cloudflare idea? Cloudflare's Lavalap Wall is running part of Internet:

"Why does Cloudflare use lava lamps to help with encryption?":

https://www.cloudflare.com/learning/ssl/lava-lamp-encryption...

I might have been thinking of this

Thanks, I always associated it with GitHub (as having "done it first" but didn't really think to push further). I appreciate the correction, I like knowing the correct information.

i used software defined radios to make a few sets of one time pads with entropy. The randomness of proper SDR or even a webcam in a lightproof coffee can or something is demonstrable with any of the tools for "testing randomness"; sibling is correct, MEMS are notorious for "noise" and that noise is "random", one can use a GM tube to trigger interrupts and use the timing to get entropy.

I don't know how you'd prove something is truly random, though, just that it looks and acts "random" enough; fitness for use.

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