On Sun, 23 Jul 2017 17:13:04 +0000 neel@neelc.org wrote:
Today, I wanted to try to see how the Internet looks behind the Great Firewall of China. I used a public HTTP proxy list (http://spys.ru/free-proxy-list/CN/) listing Chinese proxy servers (meaning getting into Chinese censorship from the US, not bypassing it in China), and guess what? I was already blocked. Why? I suspect that I was running a Tor relay from my home connection (https://atlas.torproject.org/#details/A20840A16CB658024B0D3A0E3F19A9C0E34C84...).
Some Chinese websites do load, but many of those who do usually have a CDN outside the Chinese firewall. For example, I can visit AliExpress from my home computer without Tor, but I can't visit 163.com or 2345.com.
I can confirm it with 163.com and 2345.com, inaccessible from 3 current Tor relays, and accessible from 3 non-Tor hosts.
Also if a host has been running Tor in the past, but doesn't anymore, it appears to regain access to those Chinese sites, i.e. the blocking is not permanent, the list of Tor nodes is rechecked periodically and those IPs which are no longer in it get removed from the block list.