New random number generator!
"The brightness of the object also varies dramatically, by a factor of 100, and the signal switches on and off apparently at random. We've never seen anything like it."
"The brightness of the object also varies dramatically, by a factor of 100, and the signal switches on and off apparently at random. We've never seen anything like it."
Makes me wonder if photos of the sky are sufficiently random to be used this way? Does the image vary enough and does an attacker see a sufficiently different view even if really physically close? Etc.
>Hopefully we’ll never need it. Hopefully, the primary sources of randomness used by our production servers will remain secure, and LavaRand will serve little purpose beyond adding some flair to our office. But if it turns out that we’re wrong, and that our randomness sources in production are actually flawed, then LavaRand will be our hedge, making it just a little bit harder to hack Cloudflare.
So, no, it isn't serving a purpose for millions of websites. It's 2kW of lamps running as a backup in an office nobody is going into right now to even look at.
The previous paragraph:
>> "LavaRand is a system that uses lava lamps as a secondary source of randomness for our production servers. A wall of lava lamps in the lobby of our San Francisco office provides an unpredictable input to a camera aimed at the wall. A video feed from the camera is fed into a CSPRNG, and that CSPRNG provides a stream of random values that can be used as an extra source of randomness by our production servers. Since the flow of the “lava” in a lava lamp is very unpredictable,1 “measuring” the lamps by taking footage of them is a good way to obtain unpredictable randomness. Computers store images as very large numbers, so we can use them as the input to a CSPRNG just like any other number."
This is energy spent because it looks cool, not because it's effective.
An even more minimal modification would be to use those USB-powered "glitter" lava lamps. The idea that 2 kilowatts of heat being dumped into molten wax represents some kind of efficiency optimum is completely absurd.
Or cranking up the sensitivity of a sensor.
Or reading the low bit of an ADC.
All of these provide good entropy sources without being wasteful.
Heat pumps.
Do you just prefer blackbody spectrums?
The ideal for this would be an old sensor with lots of noise since anything new would have very little visible at any ISO. Maybe even the sensor in the camera they use for the lava lamps!
A lava lamp has the benefit of being fully analog. There's no way to exploit it to make it predictable without physical access to mess with the chemistry to make the blobs stop moving around, and you'd have to do it to all of them without anyone noticing the blobs stopped blubbing. The camera on it 24/7 would make this a bit hard.
Expected return being size of the pot you can win multiplied by probability of winning. It's the first number that is lower when everybody has the same bright idea at once.
The best strategy is to not play. The second best strategy is to minimize the chance of splitting the pot.