Powers of Tau - Generating "toxic waste" from actual toxic waste

For those not familiar the new Powers of Tau ceremony allows individuals to participate in the ceremony to generate the public parameters that will be used in the upcoming Sapling release.

There have currently been 43 participants who have all varied their sources of randomness used in the process and how they prevented side-channel attacks but the latest attempt by Ryan Pierce and Andrew Miller might be the most audacious - being as they used a radioactive artefact from Chernobyl as the entropy source and performed the computation in the air. Their full write-up is here!



what are the requirement for participation?

No requirements per se but more details here: https://github.com/ebfull/powersoftau. You can read what everyone else has done here.

As for joining itself, it is done through a request to the mailing list via https://lists.z.cash.foundation/mailman/listinfo/zapps-wg

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Does anybody know if this could work on a raspberry pi computer? It’s cheaper to get destroyed as recommended …

I found this in one of the reports (round 38):

Raspberry Pi3 nodes were tested to see if they could be used, but do not
have enough RAM to complete the compute job.
PINE64 nodes were tested to see if they could be used, and while they
faired much better than the Raspberry Pi’s, they ultimately failed to
complete the compute job aswell.

Edited to add it’s not a requirement to destroy the machine either. As I understand it’s only the RAM that could contain remnants of the randomness (assuming swap is not being used) so you could simply destroy the RAM or as many others have done run a series of memory tests after completing the ceremony to ensure it has been wiped.

They also just posted a video of how it was done:

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nobody from korea/japan or china participating? maybe india?

i mean Zcash is not only for north americans right?

Interesting. I wonder if they tried with extra SWAP …
Do you know if it is possible to run a test without having to ask for a challenge file?

It’s not a requirement to reveal your location obviously, so not everyone has. I haven’t looked through them all but from memory, there is at least one from Hong Kong and plenty from Europe. I get your sentiment though and indeed there is an issue on the Zcash Foundation site about improving outreach to China Measure and improve outreach in China · Issue #46 · ZcashFoundation/ZcashFoundation · GitHub (this is in general as opposed to the ceremony). Hopefully, someone reading these forums will take up the challenge!

I’m not sure, would be a good question for the mailing list. Also reading this attestation powersoftau-attestations/report.asc at master · ZcashFoundation/powersoftau-attestations · GitHub the setup of this machine was reasonably primitive with only 2GB of RAM which worked.

Concerning the testing, the answer is here:

It shouldn’t be that difficult to test

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Another great update on the Powers of Tau ceremony is that Filippo Valsorda created an independent implementation in Go - see here for the mailing list post and here for the Github repo.

Hey there,

I tested the MPC on an Odroid C2 (2gb ram) running Debian (dietPi) and it first failed.
I then added 2gb or SWAP, and it worked :slight_smile:

Next test with a good old raspberry pi …

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update on the raspberry pi: after 40 hours of computation, black screen, no more sign… and an empty response file…

Odroid C2 is still a cheap way to do!

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I’d like to participate in this but I get an error in Rust :frowning:

I did what the github info said to do, but no success.

Check out my attestation, I had the same on a Windows build as you will be missing some compilers specifically:

on the Windows machine by downloading directly from rust-lang.org. Both machines were running the latest stable release of 1.22.1. On running the challenge on the Windows machine I encounter a link.exe error which necessitated the additional downloading of Visual Studio to fix and successfully run the challenge

Also, there is an alternate Go implementation GitHub - FiloSottile/powersoftau: An independent implementation of the Powers of Tau MPC ceremony.

Thank you. Unfortunately, this is some technical work to do, and it can be disheartening, especially to the tech-illiterate; a self contained .exe file with a GUI that does all of this would be much more welcoming. Though that’s for another thread, I suppose…

I’ll d/l Visual Studio and run this again to see what happens. Thx for the guidance :slight_smile:

Understood, but this is largely by design in that if everyone used a single .exe file there would potentially be a single point of failure. The idea is to get a whole swath of implementations and dependencies etc… so it’s completely beyond the realm of doubt that everything could have been compromised.

I get all of that, and I’m not wanting to debate the need for security :slight_smile: Of course, the more of that, the better. It would be more inviting to more people the easier it becomes. More peeps means more security (it would be an interesting math problem to know at what point more users stop mattering).

However, and here is a chance for some real leadership from the ZCash officers, perhaps it would be beneficial not only to have a video explaining what this Tau business is all about, but also a complementary element to it by showing folks what exactly to do to get this going in its present state of function. At least there would be a reference for it. And seeing as the first ceremony did not instill much confidence in many users in the crypto world (the claim of Trust, etc), this second one essentially makes that argument evaporate. Strange they are so mum…


I’ll give visual studio a try and not take this off topic any longer :slight_smile: