Anonymously send bitcoins

[terabit]

I got this idea for anonymously sending bitcoins. Let's say I am A1 and I want to send to B1. Normally the blockchain would show up: A1 --(1 BTC)--> B1. My idea is to have a service where you collect up say 1000 people and make a random permutation so A1 sends to B425 and A2 sends to B213 etc.. that way the only thing you can tell from the blockchain is that A1 sent 1BTC to one of B1,B2,.. 1000 people!

To make it happen might have every transaction go through a central address M, so all the As send 1BTC to M then the bot M randomly distributes the bitcoins (it could also split them into parts and rejoin them). The main thing is a protocol using public and private keys to let people prove if M cheated, call Ms public key KM and A1s public key K1 etc.

So all the Ai's send a encrypted message to M which they sign using Ai containing an address containing the key Ki and Bi.

M then signs using it's PGP key and encrypts using Ki every address Bi and publishes all these to its site in red.. each Ai is then required to send 1BTC as confirmation that M published the correct information and that they have saved it locally, which makes it go green. After they are all green it performs the mix. If some Bi didn't get the bitcoin they can decrypt and publish the message that M posted, proving that M cheated.

[gbl08ma]

Isn't what you described basically just a mixing service?

[terabit]

you can call it a "mixing service" if you want   

[Chang Hum]

https://blockchain.info/wallet/send-anonymously

[terabit]

https://blockchain.info/wallet/send-anonymously

good one this is exactly the way it works:

https://blockchain.info/Resources/wallet/promo/mixer.png

[Chang Hum]

https://blockchain.info/wallet/send-anonymously

good one this is exactly the way it works:

It costs 1.5% but if you're sending transactions normally you sometimes get prompted with a message asking if they can borrow your coins for the mixing service.. so in exchange for about an hours delay processing you get free coins (can't remember if it's 1% you receive or closer to the full 1.5%).

[terabit]

someone on the irc said it can be done even better using multisig:

This can all be done in a way that doesn't let the service steal. You go to the service and say "I'm mixermember bob, here is an input of mine I want to anonomize, and here is a blinded token for you to sign". The service collects many such inputs during a round. Then randomly later, you unblind the signed token he gave you in step 1... and you return and say "I'm some anonymous guy with a signed token. Add this output". then once all the inputs and outputs for a round have been collected, the mix drafts single transaction that spends all the provided inputs to all the provided outputs and gives it back to all the parties to sign. If everone is happy with it (they've been paid as requested).. they sign. the mixer would enforce quantized output sizes. the accounts cost money to get— thus my "I'm mixmember bob", and refusing to sign gets you banned.

[Stephen Gornick]

I got this idea for anonymously sending bitcoins.

Like this?



 - http://blog.ezyang.com/2012/07/secure-multiparty-bitcoin-anonymization/

[Brian Puccio]

Wouldn't a simpler thing to do be creating a new BTC wallet (in addition to your normal wallet) funding it with many of the "buy BTC with cash in the mail" options (or localbitcoins.com), using it for that one transaction and then never using it again? It would be like the one time credit card numbers that PayPal and some banks let (used to let?) people use when shopping so they wouldn't have to enter the credit card number they had in their wallet they used every day.

[josephliton]

www.bitcoinfog.com/




a "mixing service"

[Reall Blue]

Isn't what you described basically just a mixing service?

I is isn't it :p  But with the Mixing service its pretty much redirecting BTC and taking a percentage it also deletes the address (that's the part which makes it anonymous? That the address expires then cannot be traced?)

~Reall Blue