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Lava Lamps and Internet Security

By Suad Čobo


There are a lot of factors that make the Internet a secure place for all of us. However, some of them require some unexpected methods. Here is how some companies, like Cloudflare, do it.

A wall of Lava Lamps in Cloudflare's San Francisco office. (Credit: Cloudflare)

What is Cloudflare?

Cloudflare is an American company with offices all around the world dedicated to web infrastructure and website security. It provides Content Delivery Network services, Distributed Denial of Service (DDoS) mitigation, Internet Security and domain name server services. Roughly ten percent of global web traffic goes through one of Cloudflare's services.

Randomness, and How Cloudflare Uses It to Protect Us

Randomness is very important for encrypting all data. It can come from many sources. However, some of them are not as reliable as others. Computer-generated randomness is predictable since it requires a user-written code to generate random strings of characters. If attackers spot this pattern, they can potentially use this to their advantage. Real-world turns out to be a really great source for unpredictable randomness. That's why the Cloudflare office in San Francisco uses a wall of a hundred lava lamps. The movement of lava inside is almost impossible to calculate by a human.

A series of cameras are pointed in the direction of the wall inside of the lobby, which captures the movement of lava inside of lamps, 24 hours a day. The pictures are stored on Cloudflare's computers and converted into a series of numbers, with each pixel having its own numerical value. Each image then has its own string that can be used as a starting point for creating encryption keys, which are then used for verifying the identity of a client or server in a network and encrypt all the data between the two so that it is unrecognizable to a potential attacker.

Even if a person in that office stands between the wall and the camera, the system can still use that for generating randomness since a person's movement is also unpredictable and can contribute to the whole process. If the cameras get damaged or turned off temporarily, Cloudflare can replace them very quickly, and they still have other sources in their offices in London (where they take pictures of a double-pendulum) and Singapore (where the radioactive decay of a pellet of uranium is being measured).

This isn't the only case where lava lamps have been used to generate randomness. A company called Silicon Graphics designed a similar system called Lavarand in 1996, the patent of which expired in 2016. Still, these methods help in protecting us from attacks and make the Internet a much safer place.



  1. How Do Lava Lamps Help with Internet Encryption? (n.d.). Retrieved June 11, 2020, from

  2. Liebow-Feeser, J. (2017, November 6). LavaRand in Production: The Nitty-Gritty Technical Details. Retrieved June 11, 2020, from

  3. McNichol, T. (2003, August 08). Totally Random. Retrieved June 12, 2020, from

  4. Anicas, M. (2015, July 30). How To Mitigate DDoS Attacks Against Your Website with Cloudflare. Retrieved June 12, 2020, from


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