TOR. How to identify?

Question

Information Security

As far as I understand, this is done like this:
1) look at the user's IP
2) check it here: https://check.torproject.org/exit-addresses
3) if the user's IP is there, then he uses TOR
How reliable is it? What other options are there?

Answer 1

About 3 years ago I wrote an article on Habré on blocking TOR clients. In general, the algorithm is the one you described, only I automated it with scripts and monitored it with graphs. If interested, I can throw off the screen of the article, with personal development I realized that it was not completed and in some things it was not correctly implemented and, in order not to be ashamed, I deleted it.