But why lava lamps?
The Problem: Computers Can’t Generate True Randomness on Their Own
Computers follow algorithms, which are deterministic: the same input produces the same output.
For example, when a program generates a “random” number, it often uses a starting value called a seed. If you run the same algorithm with the same seed, you’ll get exactly the same sequence of numbers.
This is called pseudorandomness, and predictability can be dangerous in cryptography.
The Solution: Real-World Chaos
The wax inside a lava lamp constantly moves, forming unpredictable shapes.
Cloudflare takes advantage of this physical phenomenon through a system called LavaRand:
- A camera captures the constantly changing lava lamps.
- The images are converted into numerical pixel data.
- This unpredictable data, called entropy, is fed into a cryptographically secure random number generator.
- The resulting randomness helps strengthen encryption and secure Internet connections.
The lava lamps aren’t Cloudflare’s only source of randomness. Their data is combined with other sources, adding an extra layer of security.
The fascinating part? Sometimes, solving a complex computer science problem means looking beyond computers and into the physical world.
🔗 Learn more: https://www.cloudflare.com/learning/ssl/lava-lamp-encryption/