Which is why it came as a surprise on Tuesday when a Chinese government official claimed at a United Nations summit here that no Net censorship existed at all.
The only problem: Few cases of Net censorship are as carefully and publicly documented as the Great Firewall of China. A study by researchers at Harvard Law School found 19,032 Web sites that were inaccessible inside China.
A report from a consortium of British, American and Canadian universities concluded: "China's Internet-filtering regime is the most sophisticated effort of its kind in the world. Compared to similar efforts in other states, China's filtering regime is pervasive, sophisticated and effective."
In fact, Google has citedas the primary factor in the company's creation of the .
Read on for excerpts from Tuesday's discussion in Athens.
Chinese government official: We have talked a lot about China, and that's rather strange, because if we participate in forums like this, I think that we should spend more time reflecting on the issues that have been raised.
There are millions of Chinese that have no access to the Internet. We are here because we would like to promote openness. But we have not really raised the issue of how we could participate more fully and how we could have better access to the Internet.
We need to also protect tourists in our country. And I have to say that I am a Chinese citizen, and I feel that I need to be protected. For example, we are threatened by terrorism. We do need protection. So we should be sure that everyone can come to China, enjoy our beautiful country, and I heard with great interest what our Pakistani colleague said.
I don't think we should be using different standards to judge China. In China, we don't have software blocking Internet sites. Sometimes we have trouble accessing them. But that's a different problem. I know that some colleagues listen to the BBC in their offices from the Webcast. And I've heard people say that the BBC is not available in China or that it's blocked. I'm sure I don't know why people say this kind of thing. We do not have restrictions at all.
Nick Gowing, BBC anchor and session moderator: Would you like to elaborate on that?
Chinese official: How can I elaborate on it if we don't have any restrictions?
Some people say that there are journalists in China that have been arrested. We have hundreds of journalists in China, and some of them have legal problems. It has nothing to do with freedom of expression.
Richard Sambrook, director of the BBC World Service: I'm glad he listens in Geneva. But if he was in central China, he would not be able to listen on short-wave radio and not be able to read our Web site. This is very well established. (It's) effectively blocked...and has been for years.