The Lava Lamps That Help Keep The Internet Secure

Tom Scott · 4.3M views · 2017-11-06 · 3:59

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Overview

Tom Scott visits Cloudflare's San Francisco office to show the wall of lava lamps whose camera feed is used as a source of entropy for random number generation. It is a short explainer on how this helps secure internet encryption.

On Hacker News

The go-to short explanation whenever lava lamps, entropy sources, or Cloudflare randomness come up.

Recommended by 1 HN people across 1 months · HN mentions 2017–2024

Topics

Cryptography Probability & game theory

What people said

ceph_ · 2017-12 · Recommendation
There's a good Tom Scott video on this too. Like most of his stuff, it's well worth the watch. [VIDEO]
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Karellen · 2024-03 · Reference
ObTomScott: The Lava Lamps That Help Keep The Internet Secure [VIDEO] (Mention of the London pendulums at 2:39)
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Natfan · 2022-05 · Reference
Alternatively, just do what Cloudflare does (did?), and have some cameras pointed at lava lamps[0]. [0]: [VIDEO]
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Sources

Video by Tom Scott, played through YouTube.

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