Why focus on keyword filtering?
One reason is that the GFC’s keyword filtering mechanism allows us to probe it from outside of China. This allows us to perform two types of probing: 1) to see where in the Chinese Internet the filtering routers are located, and 2) to test keywords to find out if they are blocked or not. Locating the filtering routers can give us insights into how and why the filtering is implemented, such as our proposition that the GFC is more of a Panopticon than a firewall. Reverse-engineering the blacklist of keywords can tell us what topics the government is targeting, with sometimes surprising results such as Hitler and Mein Kampf (in Chinese) or the Deauville Asian Film Festival. A more important reason is that keyword filtering is unique compared to other forms of Internet censorship. Filtering a keyword can lead to censorship of many more topics than intended, an example is how filtering for Falun Gong (in Chinese) can lead to censorship of articles about North-Rhine Westphalia, a state in we
