thank you my friend, is it that easy to ban Tor? I read countries that tried did not succeed 100%

I would say it's easy to make Tor hard to use but that it's extremely hard to make it impossible to use.

A side note: France might also go for the honeypot strategy by strategically setting up high-throughput exit nodes.

Blocking only exit nodes would block servers from being reachable through Tor, but it wouldn't block clients that use Tor. You'd have to block all Tor relays.

This is wrong: having the list of exit nodes will allow websites to stop Tor from visiting them. That won't stop anyone from using Tor. To prevent people from using Tor you will need to block the entry nodes. And due to Tor bridges that is much harder.

Dave is technically correct so I updated the link to a more comprehensive source.

@mınxomaτ : Idon’t think so, all the country network traffic is centralised at Paris, and Paris is linked to the remaining of the world with only 1Tb/s connections. For example, if you connect to a site from Barcelanosa from village near Toulouse, you traffic will be sent to Paris before that. France is not a good place for hosting a very large bandwidth data center (and in fact most of French hosting companies host their data near Belgium which is nearer AMS-IX and London).

@user2284570 That strategy already worked perfectly fine in other countries to bust some onions in long term fed operations. That's why I mentioned it.

@mınxomaτ : But France is Europe and is definitely not the fastest in term of international bandwidth. So this can’t work. (if things are hosted near Belgium this is for that good reason).

@user2284570 Not true. Honeypotting exit nodes has nothing to do with international bandwith at all. As long as the target domain of the requested server is known, the request will go through a potential HP at the local ISP (ie. in France), whether the server requested is operational or not. Less cumulative bandwidth makes this even easier, not harder as one "rogue" server (or DNS) has more relative coverage.

This answer is completely ignoring the existence of tor bridges. It is not that simple to block tor: torproject.org/docs/bridges.html.en

“In order to block Tor all that has to be done is have the current list of Tor nodes” — Exactly. In order to stop people using Tor, all you need is an exhaustive, up-to-date list of all Tor entry nodes. Including the ones that aren't publicly listed. (Have you read about bridges yet?)

France could use zmap.io to locate bridges. Scans all IPV4 addresses in less than 45 min. Run 45 instances of this on a government budget. Now scans all IPv4 addresses every minute. How fast can you generate and distribute new Tor bridges ? It's a technology race for sure but it's very much possible and other governments have done things like this.

Won't setting up honeypot relay nodes make it easier to discover other relay nodes, including hidden ones?

At last, ..., a compelling-for-the-user reason to upgrade to IPv6.

Nice try Obama.