<p>A bitcoin exchange is using a shared web wallet where its users deposits and withdraw bitcoins. The withdrawal transactions are merged, so that the pending transactions of several users are grouped together to save tx fees. The shared wallet is backed by a normal <code>bitcoind</code> installation. </p>

<p>Let's imagine we want to confirm that particular address X belongs to the shared wallet. The address X has received Bitcoins and then some of those Bitcoins have been withdrew through other unrelated transactions.</p>

<p>Because we are the users of the same shared web wallet, we can send in and out Bitcoins from this shared wallet and we gain knowledge of some receiving and change addresses and transactions related to the shared wallet.</p>

<p>Thus, is it possible to</p>

<ul>
<li><p>To prove address X belongs to the shared wallet by analyzing the other transactions we know to belong to this shared wallet</p></li>
<li><p>Are there any tools or scripts to do this kind of blockchain analysis yet</p></li>
</ul>

CC BY-SA 3.0
2014-11-30T17:40:00.523Z
If I correctly understand what you are tying to do (I'm not sure!) then the usual way to approach this would be to move all deposits to common addresses which are used to process withdrawals. That way you are combining all coins and processing withdrawals all together using the combined coins (perhaps taking advantage of coin maturity too). You would then keep your own database of deposits/withdrawals to keep track. I'll post this as an answer if I have understood you correctly.
George
CC BY-SA 3.0
2014-11-30T20:38:30.720Z
You mean like actually proove that an address/addresses belongs to an instance on the servers where bitcoind is running? The only way to prove that is capture unecnrytped traffic from these servers but if you can do that then you have more access to do other things. the same address can be synchronised across multiple instances so, no, there is no way to analyse that kind of data from the blockchain.
Piotr Kula
CC BY-SA 3.0
2014-12-01T03:54:46.590Z
@George: No, this is being done as a third party and not being the service owner.
Mikko Ohtamaa
CC BY-SA 3.0
2014-12-01T03:59:17.450Z
@ppumkin: I was more thinking of this: you know receiving address and change addresses of the shared wallet when you do transactions there yourself. Then you run through blockchain and find other transactions which have been using the same addresses.
Mikko Ohtamaa
CC BY-SA 3.0
2014-12-01T15:28:09.497Z
Yes, clever, very clever. If the guy who implemented the "security" didn't divide bitcoind into separate servers, then yes, potentially you can start to find out allot about what's happening on that node. At least these transactions should be distributed between allot of wallets locally, there is a way to transact with 0 fees locally for security reasons like this.
Piotr Kula
<wallet><bitcoind>
Proving the address belongs to a shared wallet where one can control some deposits and withdrawals
Mikko Ohtamaa
# Proving the address belongs to a shared wallet where one can control some deposits and withdrawals

(Asked by: username_0 on 2014-11-30)

A bitcoin exchange is using a shared web wallet where its users deposits and withdraw bitcoins. The withdrawal transactions are merged, so that the pending transactions of several users are grouped together to save tx fees. The shared wallet is backed by a normal `bitcoind` installation.

Let's imagine we want to confirm that particular address X belongs to the shared wallet. The address X has received Bitcoins and then some of those Bitcoins have been withdrew through other unrelated transactions.

Because we are the users of the same shared web wallet, we can send in and out Bitcoins from this shared wallet and we gain knowledge of some receiving and change addresses and transactions related to the shared wallet.

Thus, is it possible to

* To prove address X belongs to the shared wallet by analyzing the other transactions we know to belong to this shared wallet
* Are there any tools or scripts to do this kind of blockchain analysis yet

**Tags:** wallet, bitcoind

> **Comments:**
> **username_1**: If I correctly understand what you are tying to do (I'm not sure!) then the usual way to approach this would be to move all deposits to common addresses which are used to process withdrawals. That way you are combining all coins and processing withdrawals all together using the combined coins (perhaps taking advantage of coin maturity too). You would then keep your own database of deposits/withdrawals to keep track. I'll post this as an answer if I have understood you correctly.  
> **username_2**: You mean like actually proove that an address/addresses belongs to an instance on the servers where bitcoind is running? The only way to prove that is capture unecnrytped traffic from these servers but if you can do that then you have more access to do other things. the same address can be synchronised across multiple instances so, no, there is no way to analyse that kind of data from the blockchain.  
> **username_0**: @username_1: No, this is being done as a third party and not being the service owner.  
> **username_0**: @ppumkin: I was more thinking of this: you know receiving address and change addresses of the shared wallet when you do transactions there yourself. Then you run through blockchain and find other transactions which have been using the same addresses.  
> **username_2**: Yes, clever, very clever. If the guy who implemented the "security" didn't divide bitcoind into separate servers, then yes, potentially you can start to find out allot about what's happening on that node. At least these transactions should be distributed between allot of wallets locally, there is a way to transact with 0 fees locally for security reasons like this.  

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## 0 answers

