Bitcoin Forum

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Yes, people can track your IP to a bitcoin transaction if you do not mask it.

Anyone who can eavesdrop on your network connection (such as your ISP, the NSA, or your neighbour if you use open Wi-Fi) can see if you send a transaction that you didn't previously receive, which proves you created it, and are not merely relaying someone else's transaction. Also, an early version of Bitcoin had a bug which allowed an attacker with a direct connection to your node to determine your addresses. Although this bug has been fixed, the current version may yet have similar bugs.

For these reasons, it is recommended to run Bitcoin over Tor. However, note that doing so does not necessarily make you anonymous, as there are other methods of associating your identity with your Bitcoin transactions than your IP address.

None of this is secret or controversial. Bitcoin was never intended to be completely anonymous.

One way to mitigate someone passively snooping on the network level, and finding out who is the originator of transactions would be to encrypt peer to peer communications.

Attackers who set up nodes will have to set up a sufficient amount in order to provide acceptable confidence that peer they got the transaction from is indeed the originator of the transaction.

There are a number of ways to mask where a TX originated from:

Tor
Public WiFi
Using blockchain to push a signed TX for you
running a full node and having a light client only connect to that node

well, i for once didnt know this.
i thought bitcoin was only seen by wallet address..

actualy, you can use online wallet, or a vpn for that matter.

Tor communications are encrypted peer-to-peer.

Set up your node to accept connections via a hidden service, and use -onlynet=tor to make sure you only connect to other hidden services.

Now 100% of your peer-to-peer connections are encrypted.

I am not tech literate. You can run your entire internet connection using tor? Or, are you saying use tor when using btc services or online wallet an such?

(Please, no making fun of me, I admit to being mostly computer illiterate.)

If you are running a Bitcoin node (this means Bitcoin-Qt, bitcoind, btcd, or I think Obelisk) on your own computer, and you are running a Tor client, then you can configure the Bitcoin node to only connect to the Bitcoin network via Tor.

If you're using an online wallet, then you don't have any privacy anyway so it doesn't really matter if you use Tor to access it or not.

Exactly right. That's why I've always kinda yukked up my sleeve at the "anonymous" nature of Bitcoin. Somebody could sniff out the packets used to send the Bitcoin and use the information in those packets to know where you sent it from no matter whether you sent it from your house or from your local cafe with Wi-Fi. About the only way to get around it is to use some kind of proxy service and even that isn't infallible.

This is not valid with Dynamic IP internet connections, like the connection I've right now.

That is good to know but an ISP provider retains address logs for 180 days to a year so it probably is still a valid concern
http://lifehacker.com/5923017/how-can-i-prevent-my-isp-from-tracking-my-every-move/all

By default data is associated with you, unless you take counter measures.
Dragnet surveillance is very serious nowadays. IP address is one of the many things to track you.

What if you aren't sending from a personal wallet (Bitcoin-QT, etc), rather from an exchange (Cryptsy, mint, etc)? In that situation would it still be possible to trace where it was sent from? Or, since it is the exchange's server sending the transaction, would it be anonymous?

It'll broadcast their IP if that is not masked.

Network snooping will show the transaction coming from the exchange.

The exchange, of course, knows it was your transaction and they'll have records showing such.

The same people who engage in widespread network snooping probably can just ask the exchange to give them those records (or they'll hack into the exchange and just extract the records themselves).

That's why I said if you use a web wallet you don't have any privacy.

Tor and mixing, to mask the initial input should be enough.

Anytime a transaction is done which can be traced back like some payment then mix again.

Even with a dynamic IP address your identity can still be found.

Your ISP will keep logs of who is assigned what IP address at what times.

A full peer who is not masking their activity is susceptible to transaction counting.  That is, detection of transactions which originated at the peer rather than those being relayed.  Or at least that was supposed several years ago.  Several years ago most people thought it impractical though I personally always considered it a potential threat.  Now (post-Snowden) it seems likely that fine-grained packet are captured, retained, and analyzed.  At least for anyone who is tagged for enhanced monitoring, and I think that there is a strong possibility that all Bitcoin users are.

A non-compromised https connection to a non-compromised exchange or wallet service (if there is such a thing) would be theoretically more safe.  It would require timing analysis to match user activity with transactions (if they even leave the service) and that would be very easily thwarted by introducing some random delays.  This assumes that the service is somewhat popular (and thus, active) of course.

Go ahead and say the magic words 'tor'.  For my part I never trusted it.  At least not for highly critical work.  It being largely funded by the government to 'help Iranian dissidents' doesn't pass the smell test for me.  But to each his own.

I bet it's a lot more secure now after two critical OpenSSL bugs have been fixed.

I'll feel a lot better about it if Tor ever switches to LibreSSL for encryption.

I've always been more concerned about timing analysis at the network level.  I've figured the NSA and such have taps almost everywhere.  At least since Mark Klein blew the whistle on AT&T's Narus nearly a decade ago.

An unhappy paradox is that one (or one like me) gains significant confidence in something only after it has been successfully attacked in specific ways.  TrueCrypt is a good example.

I was just thinking about saying that you could use tor right before I read your last sentence.

At least hear me out on this.....

You could write and sign a TX, use blockchain.info over tor to push the transaction while using a public wifi with a lot of people around. Or you could skip using tor and just use the public wifi although it would leak your general location but your identity would probably be hidden

There's a way to fix that, if you don't care about burning bandwidth.

Set up your node to transmit data to each peer at a fixed rate regardless of how much real traffic it actually has to send. Basically this would be 100% padding.

Disadvantages is that it eats up your bandwidth, and it puts a hard upper limit on the  maximum throughput of the network, but on the plus side timing attacks are useless.

Since the very early days (which was mid 2011 in my case) it struck me that Bitcoin has the potential to be very resilient because the data need is tiny and because it is not latency sensitive.  Absolutely the potential exists for transactions to be performed in even the most hostile environments though the methods you describe among others.

As I've alluded to before, I've assumed for some time that extensive deep packet capture and analysis has been underway.  The next shoe to drop would be active filtering.  We'd have to see compelling reason to do it, but if/when that reason comes into existence I expect that it will happen rapidly.  Even in this 'hostile environment' Bitcoin has a very real potential to continue to provide a framework for economic activity.

That said, it will never be exactly easy to use Bitcoin in an adverse environment.  A small fraction of people will have little trouble, and a growing fraction of people will develop the skills needed to do so, but we are still talking about a rarefied population.  And the notion of 'real time' activity would have to be drastically curtailed.  It never was a good fit with Bitcoin's design in the first place.  Anyway, this is the basis for my being fairly negative about efforts to extend the solution widely into the sphere of the masses and to try to forge it into a real-time solution (the domain of cash.)  Both of these will prove to be significant negatives if/when there is a genuine need for the solution.

I'm pretty much at the point now in the middle of 2014 of considering Bitcoin to be fatally damaged for the use-case that I envision as most valuable.  Maybe it could help bootstrap in a more viable and focused solution, but Bitcoin proper simply did not attempt to occupy the niche of a robust solution in a different and more hostile world than we see today.  Hopefully time will prove that it didn't matter much and nothing bad will happen in the real world.

Absolutely true!  Not only that, but in the context of Bitcoin transaction communications it would be a really good fit (see previous post on this thread.)

It would be great if some transfer nodes were employing this technique in their communications, and if they were rewarded for doing so.  As things stand now transfer nodes are not even rewarded for providing transmission services within the network at all, much less for doing it in a defensive manner.  Alas.

Even though the Bitcoin reference implementation is not as modular as I'd like it to be, at least there's enough modularity that the P2P protocol is independent of the blockchain rules.

I know someone who's been doing theoretical work on how to create a self-organizing market for realtime data propagation. Perhaps one of these days that will turn into deployed software.

this isn't a suprise, really. you can see where transactions are broadcast from, so if sending from your own client, it would appear that your IP address could be narrowed down / linked to you. i've never been concerned, really.

What was OP?
Thread starter delete cause he worried he being bmtracked now?

Annoying when OP gets  deleted..

IIRC, the body of the OP could just as well have been and 'EOM' trailing in the title.  It should not be big news to anyone that IP assignment logs are retained.  I'd be surprised if this particular bit of meta-data were not both very complete and retained indefinitely (edit: and they go back to the before y2k.)

Of course 'you' would mean whoever is paying the bill to your ISP...because even if your web-cam can be activated at will it is certain to be an unusual event.

Using an unauthorized connection to an unprotected (or weakly protected) WiFi access point (for highly sensitive transactions by "Iranian dissidents") would be a dead-end for IP address tracking, but would not be very user-friendly.

In my opinion, eventually the ISP will have as much or more responsibility for knowing and protecting customers as traditional banks.

The ISP will have to work with local laws and governments regarding privacy and accountability.

The ISP is the most likely candidate to provide proof of location, if that ever becomes a feature. ISP's could act as a signature in transactions.

If ISP's won't step up to the responsibility, Maidsafe should.

The Point is that a BTC TX can be associated to you via your IP address

Unless you are using New Universal Dollars™ ;)

I wish I knew about this before I got into Bitcoin.  I have nothing to hide so I don't mind using my plain IP but if I'm torrenting, I use a proxy just so that it's not so easily accessible.   :-\

http://prism-break.org

Dark wallet.

It's pretty easy to get internet under a fake name.

Even if you signed up under an alias wouldn't your IP address still be associated with you house/apartment?

Yes, and what if you rented in the same fake name?

Before someone says you can't pass a credit check for a place with a fake name - you can rent without doing a credit check. Just tell the landlord that you don't use a SSN on principle (Its a welfare program. Why invest in a corp that's trillions in debt? Underage contract..etc, etc). Some landlords, especially if they're desperate to rent, will let it slide. Others can be talked into it with a large enough deposit.

That sounds a lot like identity theft.

With the Bitcoin protocol, could I demand that all entities enquiring into my IP access that data only through my personal multi-signature (or authorized legal/agent) release? In other words, I get a 'you are being snooped message' - again, hidden only through legal means and well documented in the blockchain available for audit. An ultimate goal of mine would be to receive a micro-payment for something as common as a website tracking cookie and gain royalty upon its use. Doesn't matter if we think Google will do it or not, someone will and when they do... Another example, red-light cameras: Pictures go into a crypto/blockchain transaction, access is allowable for brief periods using location protected hardware (leaves the building and it automatically wipes/disables).

So someone buys the right to visually inspect that picture and i am in it. I've got copyright and also protection, and if I wasn't part of the crime (no crime, no reason to be buying up my picture, right?), then i've earned a Satoshi and was informed of surveillance. For every invasion of privacy from bitcoin I could probably come up with 10 protections or ownerships of privacy. Cameras? You take a picture in public? My phone is informed as you've broadcast your actions to the local mesh. This can be done with hardware. Off the grid and on a murky network? Ok, but you'll find your social passport shut down as you traffic in public places. Today I feel if I met a Sci-Fi B grade movie producer I would grab and shake them till they hear me, "Here's Bitcoin 2025, I've got the first 10 episodes" :D

So much is on the table. I don't think that it can be controlled, I believe it will evolve.

Bitcoin is anonymous because of the sheer number of transactions that take too long to figure out.  If you get on somebody's list, they can figure you out.

Zerocoin.

Any more information on this? My only sources come from talking to ISP support reps but they've always told me "due to the dynamic nature of allocating IPs" they can't confirm who the owner is, which to me sounds like BS because I'm sure all ISPs have to have rules in place so they can identify customers in the case of abuse.

The root of that crime is stealing anothers connection. That's the best spoof. Now if every packet were ever only shipped only with a sotoshi...

Its not too difficult to change your IP before broadcasting transactions or after broadcasting a transaction:

http://whatismyipaddress.com/change-ip - Requires you to insert a different MAC Addresses into your router homepage and unplug it for 5 mins.
https://www.privateinternetaccess.com/ - Bitcoin Accepted here!!

Edit: Clarity

The issue here is the ISP has log which can point it to you if someone want to spy on you.

Changing IP doesn't solve the problem.

Good point, I actually did not even think about that. I was just thinking about the scenario if someone wanted to target valuable wallets, you would be able to change IP's so they could not target you.

Well if you're not doing anything shady or anything dirty you shouldn't have anything to worry about.

That's if you're on a private network like a locked wi-fi....

If you are using a VPN that you are certain does not keep logs then a transaction that you broadcast would be associated with the VPN's IP address and the absence of logs would make it difficult/impossible to link the VPN back to you.

Another solution would be to use TOR, as the transaction would be associated with the TOR exit node and I don't think there are any attacks on TOR that can be done to find someone's identity via TOR that can be done retroactively.

Why not just go to the library lol

I don't want to go to the library every time I buy or send bitcoins. A VPN that doesn't keep logs is a much simpler solution. 

You could really just use TOR to use bitcoin. As long as an adversary doesn't previously suspect that you are using bitcoin then you have basically 0 chance of any kind of timing attack

That is probably the simplest solution. I must admit I don't know how to connect my wallet to TOR but this discussion has inspired me to find out.

From the TOR Wiki (https://en.bitcoin.it/wiki/Tor#bitcoind)

Still this is the type of thing that totally hurts the idea that bitcoin is really anonymous which is a big selling point on bitcoin.  Well better to know than not know I guess. But still I wasn't aware of this.

You need to have your wallet program connect to the Vidalia proxy via localhost (in proxy settings)

Or you could use blockchain.info and use TOR to connect to blockchain.info

I wonder if this is true for electrum wallets?

Definitely NOT if you're running electrum with a VPN connected.

Also, IP addresses are NOT stored in the blockchain.

A) I don't want to go to the library every time I use bitcoins.

Also, they can track wallets. (I believe)
So you'd have to generate a new wallet AND use a crappy library internet connection. :I

Well an IP is simply a number associated with a certain cable output. If said cable goes to your house.. well of course that IP can be tied to you, its basically an electronic address!

Add to that google, facebook and NSA datamining and I hope its not a surprise to anyone ever.

I've never been able to fully access the wallet section of blockchain.info using TOR, anybody else had these problems?

Though TOR is not safe anymore itself unless you are taking multiple other steps with it together.

I periodically fire up Tails (ie. tor) to mix my coins via blockchain.info's service. No problem so far.

Thanks for sharing that. I don't do anything illegal or even suspicious with bitcoin but I value my privacy. I also have a healthy fear of hackers seeing that I run a node. 

If you look at cases where people have been identified when using TOR it's because they either had the stupid idea of logging into personally identifiable accounts at the same time as logging onto other sites they shouldn't be on.

People who assume TOR itself will keep you hidden are naive and wrong, how can one piece of software hide your identity if your foolish enough to do something like log into Facebook while on Silk Road?

Always assume someone is watching and prepare from that. That's why Bitcoin is so great, sure you can say address x did x transaction at y time, but you can't prove address x belongs to me unless I've confirmed ownership somewhere else. You could even apply this rule to IP addresses, sure that IP address is mine but can you prove it was it was me on my machine? For all you know it could have been a relative staying over or someone who decided to crack my AP and abuse it.

Was their an article or something orignaly ?
OP now just says "X" - I assume their was something more exciting relating to an article or blog post or some thing worth discussing ?

Kinda annoyed I missed it. If anyone can link that would be great :) ??

Thanks peoples

Tor traffic and messages are suppose to be encrypted and randomly routed to the destination. Meaning logging in silk road and facebook at the same time shouldn't compromise the user identity.

you have to be encrypting the data on your computer while offline and then sending it online with the end user already knowing how to decrypt the

data having met u in person and being provided with the decryption method their is no other possible way for it to be secure

also assuming your encryption method is strong enough not to be cracked

and when your encrypting the data offline you have to be sure their isn't a dormant process running that will deliver stored content

when your computer comes online, also yes your ip packet will always be identifiable,

can someone post a screen shot of an packet delivered on the tor network

the bitcoin blockchain is supposed to be secure because it cannot be reproduced

which is a combination of network power and encryption

If you log into both from the same computer then an attacker could potentially do a timing attack against you.

In order for TOR to work best, it is important that you do not use any other browsers to programs connected to the internet when using TOR.

Speaking of TOR, this just popped up on my fixture news search tab:

  http://in.reuters.com/article/2014/07/22/cybercrime-conference-talk-tor-idINKBN0FR05V20140722

The banking crisis of the 2007-ish timeframe was partially solved by changing the accounting rules for banks (or allowing certain rules to not be ignored and assets 'marked to model') which kept banks in the banks balance sheets in the black or close enough.  It looks to me like the robustness for purpose for TOR might be solved in a substantively different but equally ludicrous manner.