LavaRand in Production: The Nitty-Gritty Technical Details

Cloudflare uses lava lamps in its lobby to generate random numbers for cryptography. The unpredictable flow of "lava" in the lamps provides a source of true entropy. A camera captures images of the lava lamps, which are then used to create an entropy feed available to production machines. LavaRand is designed to ensure that Cloudflare's production machines have access to secure randomness even if their local entropy sources are compromised.