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A wall of lava lamps helps encrypt the internet

atlasobscura.com

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Re: A wall of lava lamps helps encrypt the internet

#121

Post by Crontab »

scoggs wrote: post #108
jlgaddis wrote: post #69

Earlier quoted context omitted.

> We're not the first ones to do this. Our LavaRand system was inspired by a similar system first proposed and built by Silicon Graphics and patented in 1996 (the patent has since expired). -- https://blog.cloudflare.com/randomness-101-lavarand-in-produ...

I know that people patent things for various reasons but would people truly expect the holder of that patent to litigate against another company using that method to ensure "more true" randomness in whatever application they were using? I, personally, imagine the patent holder would be glad to see others using their method to ensure true randomness so long as they were using the technology for anything other than evi…

In today's world, yes, I would expect a patent holder to sue.

Re: A wall of lava lamps helps encrypt the internet

#122

Post by hinkley »

adzm wrote: post #96
ams6110 wrote: post #88

Earlier quoted context omitted.

IIRC a standard size lava lamp used much less than a 100W bulb. So your costs are maybe half that.

40W on mine fwiw

As someone else pointed out, they overheat. So if you want to run them all day you might go down to a 30 or 25 watts.

But there are probably a bunch of other Brownian motion machines you could use that take a lot less power. Like those glitter lamps. You’d need a higher res camera.

Re: A wall of lava lamps helps encrypt the internet

#123

Post by [deleted] »

rm999 wrote: post #23
samuel wrote: post #17

I might be prejudiced, but this looks like a big PR stunt/done for the cool factor kind of thing. Aren't there simpler/saner alternatives for getting good randomness?

For sure. In another office they use a geiger counter (a much more standard way to get randomness, and probably easier to setup). That said, this doubles as a public art installation in their lobby - something many companies spend thousands (or millions!) of dollars on. So it's not just PR, it's actually surprisingly practical.

[deleted]

Re: A wall of lava lamps helps encrypt the internet

#124

Post by hinkley »

pbhjpbhj wrote: post #81
Kequc wrote: post #80

That's approximately 100 lava lamps each at 100W = 10,000W = 10kW/h * 20.4 cents = $2.04/h * 24 = $48.96/day $1,489.20/month. Ignoring the fact that is very little money in Silicon Valley. Lava lamps consume a large amount of electricity in order to generate the heat they need. There are cheaper better ways to generate randomness, this is purely for spectacle clearly. It makes me nervous more than anything. If that's…

They should "power" the lamps with excess CPU/processor heat.

Not too much power though. They can explode.

Re: A wall of lava lamps helps encrypt the internet

#125

Post by cmpxchg »

shagie wrote: post #30
samuel wrote: post #17

I might be prejudiced, but this looks like a big PR stunt/done for the cool factor kind of thing. Aren't there simpler/saner alternatives for getting good randomness?

I suspect its a matter of getting a lot of random rapidly with easily replaceable and unregulated devices. The classic HotBits ( https://www.fourmilab.ch/hotbits/ ) uses radioactive decay to get its random data. This generates 100 bytes per second of randomness. But that also depends on getting a radiation source. A single one costs about $80. A lava lamp costs $10. Working off the list of isotopes that they provide,…

A 10 μCi 137Cs source is not dangerous. Even here in California, you can legally throw these away in the regular trash (if solid) or wash them down a sink drain (if liquid). Compared to the kind of ordinary household chemicals people are using every day in large volumes, these things are harmless. You definitely don't need a lead-lined room.

Source: I worked in a lab

Re: A wall of lava lamps helps encrypt the internet

#126

Post by minitech »

jorgec wrote: post #112

Generating a random number by using microseconds as a seed is more than enough for practically every single case. It still hasn't been cracked or predicted. Some people say that, in theory, it could be cracked however, i tried and its impossible, modern computers are so complex and fast that it gives enough entropy.

That’s dangerously wrong. If you generated a password using only microseconds as a seed, an attacker who knew the day you did it could crack (an MD5 hash of) the password within a few minutes, for example.

Re: A wall of lava lamps helps encrypt the internet

#128

Post by NightlyDev »

Kequc wrote: post #80

That's approximately 100 lava lamps each at 100W = 10,000W = 10kW/h * 20.4 cents = $2.04/h * 24 = $48.96/day $1,489.20/month. Ignoring the fact that is very little money in Silicon Valley. Lava lamps consume a large amount of electricity in order to generate the heat they need. There are cheaper better ways to generate randomness, this is purely for spectacle clearly. It makes me nervous more than anything. If that's…

100 watt is way too much, 25W/each is a more realistic number.

Re: A wall of lava lamps helps encrypt the internet

#130

Post by schoen »

A lot of confusion in this discussion thread and other promotions of this idea stems from the intuition that you can "run out" of entropy in your random number pool if you don't periodically replenish it with a physically unpredictable source. I have had this intuition too. Two things that feed it are the Linux random(4) man page and the behavior of GPG when generating a new private key.

tptacek tried to explain some of the problems in this intuition at https://sockpuppet.org/blog/2014/02/25/safely-generate-rando..., which relates to why he's so annoyed at some things people have said in this thread (and when discussing CSPRNG seeding in other places).

I like the idea of feeling physically unpredictable data into the CSPRNG, but for most purposes it's a misconception that doing so on an ongoing basis is in any way required by the design or that heavy users of randomness like CloudFlare would "run out of entropy" or "exhaust their entropy pool" if they didn't do so. The design of existing CSPRNGs would let CloudFlare use /dev/urandom for as long as it likes after securely seeding it just once, and there's no known cryptanalytic attack to which this practice would be vulnerable.

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