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"All your bitcoin dealings are going to be public" is really only true if someone gets a hold of your wallet, or if you are using the same Bitcoin address for e

"All your bitcoin dealings are going to be public" is really only true if someone gets a hold of your wallet, or if you are using the same Bitcoin address for each transaction. By default, every time you send or receive you are given a new 'default' address. If you don't use that, then yeah, a group of transactions can be linked to you. Otherwise your identity would have to be 'disclosed' for each different address separately. Unless of course someone gets your wallet, but then as far as I'm concerned, you've got bigger things to worry about it.

coderrr 15y ago
"Otherwise your identity would have to be 'disclosed' for each different address separately." Actually, it's a lot worse than that. Most people will have a majority of their addresses linked without knowing it. http://coderrr.wordpress.com/2011/06/30/patching-the-bitcoin-client-to-make-it-more-anonymous/ http://coderrr.wordpress.com/2011/06/30/patching-the-bitcoin...
- feral 15y ago
  I've done some work on this (http://arxiv.org/abs/1107.4524 http://arxiv.org/abs/1107.4524) and the phenomenon that coderr describes is very widespread in practice (we can examine this passively, from the transaction history) and its linking identities we can be pretty sure the users didn't intend to have linked. I'd say that anyone concerned about anonymity should be using a client with the functionality that coderr's patch provides, and be incredibly careful using Bitcoin in general.
- narcissus 15y ago
  Thanks for the link: that's really interesting. I guess that's more a problem with the official client more than the protocol itself, though, right? If you were to create a new address and have all of those 'trackable' addresses send their balances to that new address, haven't you essentially removed this problem? I mean, all the people that sent to you in the first place can see where you sent the coins to, but they can't prove that you are holding that new account. Or is there something I'm missing here? For what it's worth, I completely see how this is a problem. However, I don't see it as a particularly hard problem to solve (even 'programatically'). EDIT: and it was until I read the other reply here that I realised that that is actually your blog post. Nice work!
  - coderrr 15y ago
    Yea if you send coins to a new address no one can prove you own that address. You have to be careful though. If you send 100% of your known linked addresses to a new address it's pretty obvious that you own the new address too and have just moved your coins to it. It's a pretty complicated area to reason about. I expect there will be a lot more research on it in the coming years.

coderrr 15y ago

"Otherwise your identity would have to be 'disclosed' for each different address separately." Actually, it's a lot worse than that. Most people will have a majority of their addresses linked without knowing it. http://coderrr.wordpress.com/2011/06/30/patching-the-bitcoin-client-to-make-it-more-anonymous/ http://coderrr.wordpress.com/2011/06/30/patching-the-bitcoin...

feral 15y ago
I've done some work on this (http://arxiv.org/abs/1107.4524 http://arxiv.org/abs/1107.4524) and the phenomenon that coderr describes is very widespread in practice (we can examine this passively, from the transaction history) and its linking identities we can be pretty sure the users didn't intend to have linked. I'd say that anyone concerned about anonymity should be using a client with the functionality that coderr's patch provides, and be incredibly careful using Bitcoin in general.
narcissus 15y ago
Thanks for the link: that's really interesting. I guess that's more a problem with the official client more than the protocol itself, though, right? If you were to create a new address and have all of those 'trackable' addresses send their balances to that new address, haven't you essentially removed this problem? I mean, all the people that sent to you in the first place can see where you sent the coins to, but they can't prove that you are holding that new account. Or is there something I'm missing here? For what it's worth, I completely see how this is a problem. However, I don't see it as a particularly hard problem to solve (even 'programatically'). EDIT: and it was until I read the other reply here that I realised that that is actually your blog post. Nice work!
- coderrr 15y ago
  Yea if you send coins to a new address no one can prove you own that address. You have to be careful though. If you send 100% of your known linked addresses to a new address it's pretty obvious that you own the new address too and have just moved your coins to it. It's a pretty complicated area to reason about. I expect there will be a lot more research on it in the coming years.