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Bitcoin => Project Development => Topic started by: onelineproof on December 31, 2011, 02:05:30 PM



Title: idea for mixing service
Post by: onelineproof on December 31, 2011, 02:05:30 PM
So with mixing services, the problem is usually "How can I trust the server that does the mixing?"

But what about having a webcam livestream the server and also allow people to physically visit it to make sure that the stream is not corrupt?

The stream would be sent encrypted with PGP, so people physically visiting the server would have to verify that the server actually can sign messages with the correct key, and also make sure that no one else has gotten access to the private key. Also make sure the equipment there functions as it should...

The first time it goes live, it generates a new private key in front of anyone who wants to physically be there, and then those people can monitor the livestream to ensure that everything stays as it was. People who weren't physically there when the key was generated won't be sure that no one else has the key, but they can trust their friends (if they were there), or they can come the next time a new key is generated.

I thought of this kind of thing before when I was thinking of a way to make a trustworthy online voting system. It's still a rough idea, and it may be very hard to do for practical purposes, but can this be a way?


Title: Re: idea for mixing service
Post by: ripper234 on December 31, 2011, 02:39:05 PM
So with mixing services, the problem is usually "How can I trust the server that does the mixing?"

But what about having a webcam livestream the server and also allow people to physically visit it to make sure that the stream is not corrupt?

The stream would be sent encrypted with PGP, so people physically visiting the server would have to verify that the server actually can sign messages with the correct key, and also make sure that no one else has gotten access to the private key. Also make sure the equipment there functions as it should...

The first time it goes live, it generates a new private key in front of anyone who wants to physically be there, and then those people can monitor the livestream to ensure that everything stays as it was. People who weren't physically there when the key was generated won't be sure that no one else has the key, but they can trust their friends (if they were there), or they can come the next time a new key is generated.

I thought of this kind of thing before when I was thinking of a way to make a trustworthy online voting system. It's still a rough idea, and it may be very hard to do for practical purposes, but can this be a way?


Are you trolling or serious? It's hard to tell these days.
Proper mixing will be accomplished via Contracts (https://en.bitcoin.it/wiki/Contracts), not cameras.
I believe there was a suggestion by Meni for a secure mixing service without using contracts. Still, no cameras.


Title: Re: idea for mixing service
Post by: onelineproof on January 01, 2012, 02:55:57 PM
No, I don't think I'm trolling. Just throwing out an idea. Take it or leave it. Although, my hope is that someone would explain why they agree or disagree with my system.

Thanks for the links by the way. Meni's system sounds promising (kinda like like the Tor network). But there's still the small possibility that all the nodes you go through keep logs... Also, unlike Tor, it costs money if a node does not correctly relay the information. So then the Contracts system may be able to help out with that problem by creating an incentive for nodes to properly relay.


Title: Re: idea for mixing service
Post by: Meni Rosenfeld on January 01, 2012, 05:08:36 PM
Proper mixing will be accomplished via Contracts (https://en.bitcoin.it/wiki/Contracts), not cameras.
Can you link to a discussion of using contracts for this? Does this application solve the problem of the counterparty keeping logs and releasing information? Or do you simply mean a transaction with 2 inputs and 2 outputs so neither party can steal the money? Maybe OpenTransactions can do something about the anonymity.

I believe there was a suggestion by Meni for a secure mixing service without using contracts. Still, no cameras.
For reference, This (https://bitcointalk.org/index.php?topic=54266.0) is the post ripper234 had in mind.


Although, my hope is that someone would explain why they agree or disagree with my system.
The first problem is that video footage of the server doesn't give any information about what it is doing internally. (Then again, as I recall, immersing a computer chip in ketchup and putting it in the microwave does reveal information on internal state, so you never know.)

Also, unlike Tor, it costs money if a node does not correctly relay the information.
You can only lose money if you make a blunder on your end, you're not at the mercy of other nodes in this regard.


Title: Re: idea for mixing service
Post by: onelineproof on January 02, 2012, 05:15:13 PM
The first problem is that video footage of the server doesn't give any information about what it is doing internally. (Then again, as I recall, immersing a computer chip in ketchup and putting it in the microwave does reveal information on internal state, so you never know.)

As I mentioned, anyone can come to physically inspect its internal state. And it would obviously have to be set up so that no one can log in remotely. I'm not saying it's easy to do, but in principle it can be done. But for now I think it's not worth the effort because there are other pretty good ways to implement mixing. But it can have future applications as a way to solve the common and general problem of how do you trust that a remote server is doing what it says it's doing.