Tor nodes is commonly used terminology for the nodes that route communications on the Tor network. Although it should be noted that technically clients could be considered Tor nodes, this isn't how the term is very commonly used. You can specifcy that you have an exit node. It is also very easy to see if you are being used for an entry node, simply compare the IP addresses sending you data to the public list of Tor node IP addresses that all clients have. If an IP sending you information isn't another public Tor relay it is either a bridge (easy to confirm by trying to use it as a bridge) a hidden service or a client. Adding nodes to the network to enumerate Tor client IP addresses is one of the least effective ways to go about it, since clients select three nodes that they always use to enter traffic into the network if they are up. These are called entry guards and they protect from a lot of attacks. It would be much easier to just get a warrant to passively monitor some of the directory authority nodes, where all Tor clients that do not use bridges directly connect to bootstrap a list of all public Tor nodes. After all you need to get a list of Tor node IP addresses if you want to use the Tor network. If you use a bridge it acts as a proxy between you and the directory authority nodes though. The biggest problem with his thought experiment is that he assumes the most active Tor clients are drug vendors or buyers. The Tor network had over a hundred thousand users before there was even a single Tor hidden service drug forum (that I knew about anyway, although I am pretty sure I was a member of the first hidden service drug forum several years ago). He needs to tweak his attack a little. Instead of assuming that the most active Tor nodes are drug vendors, you need an additional bit of information. This is rough geolocation of vendors. This leaks when they send mail out via the postal network. Now you can see the Tor clients who are within say a fifty miles of where packages were roughly shipped from. There are a shit ton of Tor clients that are very active and that have absolutely nothing to do with the drug trade. There are probably very few Tor clients in any given fifty mile radius, and unfortunately vendors leak their rough geolocation when they send mail out. This is a very dangerous attack and it will be quite effective at fucking vendors,(probably) particularly if they don't use bridges. Didn't SR ship product out before? The postmark will leak his rough geolocation at least down to city he mailed from if not more. I wonder how many people use Tor in that area? Probably not many. Also you are totally brainwashed to think it isn't worth it economically to the police to bust small scale drug users. They are spending free money that they steal from the tax payers, and as far as they are concerned a bust is a bust. Maybe the feds only care about larger scale traffickers usually, but you are naive if you think that local police forces will not attack SR as well. If the local police in small Texas City find a SR user in New York they will just seamlessly forward the case on to the NY police. There is actually substantial coordination between local police forces, particularly against small scale cyber criminals. If you don't think your local police department cares if you buy a few grams of coke, why is it that there are people in jail over a few grams of coke? Yes this is why his theory is incorrect. Drug users are a small minority of Tor users. Although this may be changing thanks to all of the publicity SR has been getting. Also understand the difference between evidence and intelligence. Using your own bridge to access the Tor network is certainly helpful against a wide variety of serious attacks. But it isn't impossible or even particularly hard to tell that someone is using a Tor bridge. It is a lot harder to tell someone is using a Tor bridge than to tell someone is using the Tor network without a bridge though. Again drinking the koolaid that LE want to stop drugs. LE want to make money for LE and justify their budgets. Of course they make more money for their department / agency when they steal it from a big coke lord, but busting people for minor drug offences is a large part of an individual agents bread and butter. 15,000 new people in jail = big profits for the private prison industry, parole industry, drug testing companies etc. It isn't small bucks for them, and they don't care how much it cost to bust those 15k people because it isn't like they are spending their own money on it.