4 ms·

I think they're just using their internal entropy generator. They use the lava lamps as part of that, and the internal generator for all sorts of stuff. https

by Navarr 9y ago

I think they're just using their internal entropy generator. They use the lava lamps as part of that, and the internal generator for all sorts of stuff. https://twitter.com/grittygrease/status/727587915090403328 https://twitter.com/grittygrease/status/727587915090403328

eastdakota 9y ago
Yup.
JshWright 9y ago
Yeah, I was just pointing out the fact that you don't need an external entropy source, since the Pi has a (little known?) hwrng. Makes for a neat little self-contained project.
sucrose 9y ago
Neat, I've never heard of the lava lamp wall before. That's extremely interesting. For anyone else that is interested in how it works, I found this explanation on Reddit from /u/kaihatsusha: "Really good encryption relies on perfectly random / unpredictable numbers. If you ask a computer to pick a random number, it can really only apply a predictable but complicated calculation on some other number. It may appear random to us but it isn't random to someone who can perform the same calculation. It's like stacking the deck in Poker games. In computers, "entropy" is essentially a measure of chaos; a bit of information you can get from something that is truly unpredictable. So the idea here is for a video camera to digitize a physical, chaotic phenomenon, like lava lamps or fish in an aquarium or a busy city sidewalk. Use the digitized photo as the core of the random-number generation proceas. And then two computers could use the same secret random number to seed their encryption; only those who know the secret number will be able to set their Ovaltine Secret Decoder Ring to the correct setting (except in modern days it's hundreds of rings with quintillions of positions each). In the Cold War, we would do the same thing by measuring moisture in the clouds or drawing numbered balls out of a lottery tumbler. Some crypto programs ask the user to wiggle their mouse for a few seconds to generate entropy. Make ONLY two copies of the data and those two people can communicate secretly."
- thwarted 9y ago
  The idea and implementation has been around a while. Lavarand was an early (or first) one. https://en.wikipedia.org/wiki/Lavarand https://en.wikipedia.org/wiki/Lavarand

by Navarr 9y ago

eastdakota 9y ago

Yup.

JshWright 9y ago

Yeah, I was just pointing out the fact that you don't need an external entropy source, since the Pi has a (little known?) hwrng. Makes for a neat little self-contained project.

sucrose 9y ago

Neat, I've never heard of the lava lamp wall before. That's extremely interesting. For anyone else that is interested in how it works, I found this explanation on Reddit from /u/kaihatsusha: "Really good encryption relies on perfectly random / unpredictable numbers. If you ask a computer to pick a random number, it can really only apply a predictable but complicated calculation on some other number. It may appear random to us but it isn't random to someone who can perform the same calculation. It's like stacking the deck in Poker games. In computers, "entropy" is essentially a measure of chaos; a bit of information you can get from something that is truly unpredictable. So the idea here is for a video camera to digitize a physical, chaotic phenomenon, like lava lamps or fish in an aquarium or a busy city sidewalk. Use the digitized photo as the core of the random-number generation proceas. And then two computers could use the same secret random number to seed their encryption; only those who know the secret number will be able to set their Ovaltine Secret Decoder Ring to the correct setting (except in modern days it's hundreds of rings with quintillions of positions each). In the Cold War, we would do the same thing by measuring moisture in the clouds or drawing numbered balls out of a lottery tumbler. Some crypto programs ask the user to wiggle their mouse for a few seconds to generate entropy. Make ONLY two copies of the data and those two people can communicate secretly."

thwarted 9y ago
The idea and implementation has been around a while. Lavarand was an early (or first) one. https://en.wikipedia.org/wiki/Lavarand https://en.wikipedia.org/wiki/Lavarand