Tracking bitcoins to Ulbricht, how?

[Blinken]

In court testimony yesterday, supposedly some guy name Yum demonstrated that millions of dollars in bitcoins were transferred to Ulbricht's "laptop". Assuming you could prove the IP of the laptop you would still have to demonstrate that a particular transfer went to a particular IP address. How can you do that? When transactions are verified, I don't think the verifying clients know the IP address of the recipient do they? The bitcoins go to a bitcoin address, not an IP, so how would you even find out an IP address at all?

If anybody has Yum's actually testimony transcript I would be interested in reading that.

[CryptoCobaine1]

In court testimony yesterday, supposedly some guy name Yum demonstrated that millions of dollars in bitcoins were transferred to Ulbricht's "laptop". Assuming you could prove the IP of the laptop you would still have to demonstrate that a particular transfer went to a particular IP address. How can you do that? When transactions are verified, I don't think the verifying clients know the IP address of the recipient do they? The bitcoins go to a bitcoin address, not an IP, so how would you even find out an IP address at all?

If anybody has Yum's actually testimony transcript I would be interested in reading that.

Well they have his laptop. So i'm assuming they didn't have to track ip's?

[Blinken]

Ok, so you are saying they just extracted the transactions out of his wallet?

That does not sound like "tracking". In the news article it claims the testimony was about IP tracking.

[odolvlobo]

Well, since bitcoins are not actually stored in a wallet, my interpretation of "transferred to Ulbricht's laptop" is "sent to an address whose private key is in a wallet on his laptop."

[acoindr]

Assuming you could prove the IP of the laptop you would still have to demonstrate that a particular transfer went to a particular IP address. How can you do that? When transactions are verified, I don't think the verifying clients know the IP address of the recipient do they? The bitcoins go to a bitcoin address, not an IP, so how would you even find out an IP address at all?

The problem with anonymity in Bitcoin (depending how you look at it) is there can be an easy data trail for anyone interested. Bitcoin is called pseudo-anonymous because identity isn't directly linked to transactions/addresses, and it can be cumbersome to unscramble, but that doesn't mean identity can't be linked.

You're right that the blockchain doesn't record IP address info but that doesn't mean that nobody does. Take a look at this page for a recent transaction:

https://blockchain.info/inv/0000000000000000156306d6b1a1b241dad7b87ef34a2046c7d135cdabd617e5

Anyone sending transactions from their own node can be identified fairly easily if anyone is interested. In the case of Ulbricht, though, I'm guessing they have the private keys, and therefore the public keys involved in all historically recorded transactions, on that laptop. To really get paranoid grab an address you've used before or know about and check it here.

Well, since bitcoins are not actually stored in a wallet, my interpretation of "transferred to Ulbricht's laptop" is "sent to an address whose private key is in a wallet on his laptop."

Yes, this is what I think too.

Edit: the link above was actually a block; here is an IP page of transactions

[Blinken]

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Anyone sending transactions from their own node can be identified fairly easily if anyone is interested.
....

I assume you mean by network propagation tracking? How exactly does that work? I saw your link and the IP addresses but did not understand how they were being derived.

[acoindr]

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Anyone sending transactions from their own node can be identified fairly easily if anyone is interested.
....

I assume you mean by network propagation tracking? How exactly does that work? I saw your link and the IP addresses but did not understand how they were being derived.

I haven't actually built a tool but I think the answer comes from the following.

https://en.bitcoin.it/wiki/Network

Everyone broadcasts an addr containing their own IP address every 24 hours. Nodes relay these messages to a couple of their peers and store the address if it's new to them. Through this system, everyone has a reasonably clear picture of which IPs are connected to the network at the moment. After connecting to the network, you get added to everyone's address database almost instantly because of your initial addr.

Anybody with a good picture of the network can then monitor which node first broadcasts a block or transaction, which is how I think blockchain.info derives its 'first seen by'.

If you're sitting at your home computer, running Bitcoin Core, and make a transaction, then that and its associated address can be quickly traced back to your residence.

[The00Dustin]

To the best of my knowledge, the blockchain.info IP address list and transactions lists based on IP addresses are not related to the original transmitter or the addr command at all.  The IP address recorded by blockchain.info is simply the first IP address to relay the transaction to one of blockchain.info's nodes.  Assuming the original transmitting node is connected directly to a blockchain.info node, it could be the original transmitter's IP, but it is more likely to be another node relaying transactions after receiving it (also not necessarily from the original transmitter).

[TheGame]

In court testimony yesterday, supposedly some guy name Yum demonstrated that millions of dollars in bitcoins were transferred to Ulbricht's "laptop". Assuming you could prove the IP of the laptop you would still have to demonstrate that a particular transfer went to a particular IP address. How can you do that? When transactions are verified, I don't think the verifying clients know the IP address of the recipient do they? The bitcoins go to a bitcoin address, not an IP, so how would you even find out an IP address at all?

If anybody has Yum's actually testimony transcript I would be interested in reading that.

You can trace any transactions on the blockchain and he just had the wallets stored on his laptop. They will have just used programs to track the movements to those wallets on his pc to and from the silk road and bingo, they got their man. No one is going to be anoymous if they find out who the actual wallet addresses belong to as everything can be traced unless you're careful and use plenty of mixers etc.

[picolo]

....
Anyone sending transactions from their own node can be identified fairly easily if anyone is interested.
....

I assume you mean by network propagation tracking? How exactly does that work? I saw your link and the IP addresses but did not understand how they were being derived.

I haven't actually built a tool but I think the answer comes from the following.

https://en.bitcoin.it/wiki/Network

Everyone broadcasts an addr containing their own IP address every 24 hours. Nodes relay these messages to a couple of their peers and store the address if it's new to them. Through this system, everyone has a reasonably clear picture of which IPs are connected to the network at the moment. After connecting to the network, you get added to everyone's address database almost instantly because of your initial addr.

Anybody with a good picture of the network can then monitor which node first broadcasts a block or transaction, which is how I think blockchain.info derives its 'first seen by'.

If you're sitting at your home computer, running Bitcoin Core, and make a transaction, then that and its associated address can be quickly traced back to your residence.

Ulbricht knows that and you would think he would have acted accordingly.
I am waiting for BraveTheWorld next video on the trial : https://www.youtube.com/user/BraveTheWorldChannel/videos

[deluxeCITY]

To the best of my knowledge, the blockchain.info IP address list and transactions lists based on IP addresses are not related to the original transmitter or the addr command at all.  The IP address recorded by blockchain.info is simply the first IP address to relay the transaction to one of blockchain.info's nodes.  Assuming the original transmitting node is connected directly to a blockchain.info node, it could be the original transmitter's IP, but it is more likely to be another node relaying transactions after receiving it (also not necessarily from the original transmitter).

This still will potentially lead anyone back to the original person who transmitted the transaction. The government could go to the owner of such IP address to get their logs and find out where they got the transaction from, and repeat the process until they find the person who actually transmitted the transaction.

This however is not how they made the link. They made such link by looking at the addresses that the SR servers control and looking at the addresses that Ross's laptop controlled and linking transactions together via the blockchain

[The00Dustin]

This still will potentially lead anyone back to the original person who transmitted the transaction. The government could go to the owner of such IP address to get their logs and find out where they got the transaction from, and repeat the process until they find the person who actually transmitted the transaction.

This however is not how they made the link. They made such link by looking at the addresses that the SR servers control and looking at the addresses that Ross's laptop controlled and linking transactions together via the blockchain

So are you telling me that bitcoind (and bitcoin-qt) or some other commonly used bitcoin node software actually keeps logs of all received (and transmitted?) transactions with IP information, or are you just being paranoid?