A Wall of Lava Lamps That Generate Enough Randomness to Help Keep the Internet Secure

In a random, non-sponsored episode of Amazing Places, host Tom Scott visited the San Francisco headquarters of Cloudflare, a reverse proxy company that improves website performance and security. Upon entering the office, Scott encountered a beautiful wall of colorful lava lamps. While pretty to look at, these lamps are actually used to generate cryptographic entropy in generating random numbers. The company videotapes the lamps and turns the footage into a stream of “random, unpredictable bytes” to generate secure encryption keys.

In short, these folks deal with a lot of encrypted Internet traffic, so they need a lot of random numbers. It is possible to write code that will simulate randomness, and that’s good enough for a lot of uses, but in theory, those numbers could be predicted. They’re just being generated by code, so the servers here have to get their randomness from an external and entirely unpredictable source. …hence lava lamps.

Lori Dorn
Lori Dorn

Lori is a Laughing Squid Contributing Editor based in New York City who has been writing blog posts for over a decade. She also enjoys making jewelry, playing guitar, taking photos and mixing craft cocktails. Lori can be found posting on Threads and sharing photos on Instagram.