Comment by EGreg

Can I ask how can a service be blocked in a country?

Is it because it has centralized servers? What if it was open source and could be hosted on any website?

Then they would have to detect signatures of the protocol and block that, right? At what level, the national level? But the server would be local.

So what does it mean when they say they block Tor for instance?

How can you block something that is run on many domains and servers inside your country?