Chinese journalists from Xinhua News Agency work at their office in the Main Press Centre (MPC) in Beijing.
IT WAS John Gilmore, founder of the Electronic Frontier Foundation, who said that the internet interprets censorship as damage and routes around it. For years, the Chinese authorities have done their best to prove him wrong. Now a group of hackers has launched an attempt to stamp out censorship there - and they want your help to do it.
Earlier this month week the Chaos Computer Club, a German-based hacking group, used its website, ccc.de, to launch a toolkit designed to help journalists reporting from the Olympic Games get uncensored access to Western websites. The toolkit was made available to journalists on a USB key that the CCC calls the Freedom Stick.
The Chinese authorities have censored access to Western sites from within the country for years, but in the run-up to the Games the issue became increasingly problematic - and public. The authorities have been sputtering towards the idea of an open internet, first declaring that journalists could access previously filtered Western sites and then reneging on the idea at the 11th hour. According to the Open Net Initiative (opennet.net), which monitors state surveillance and filtering online, the Chinese Government has opened access for the media to many sites but it is still using techniques to stop access to sites when users search on certain keywords.
What is not clear is whether everyone in China has access to the sites that have been opened, nor whether they will remain available after the Games are over.
CCC's downloadable toolkit contains software that provides access to Tor, a network of computers designed to make internet traffic anonymous. Tor consists of volunteer computers that relay traffic between each other without knowing its ultimate source or destination. It makes it difficult for observers to track where internet traffic is going - or who sent it.
Tor isn't new. It was originally based on technology developed by the US Navy. But it is appropriate for the job, says Fred von Lohmann, of the Electronic Frontier Foundation, which sponsored the development of the network until 2005. "Tor lets you see what the world looks like from someone else's net connection," he says.
It isn't foolproof, though, points out Johannes Ullrich, chief research officer at the SANS Institute, an online security research and training centre. "Observers could look at the Tor server's end-to-end exit points. You have to connect to Tor and it downloads a list of the possible Tor nodes that you could connect to," he says.
If the Chinese find the Tor nodes that people are connecting to, or the servers that provide the list of public nodes, they could block those, too.
But the CCC hoped to have an answer for that, involving computer users against censorship based outside China. Last year, the creators of Tor developed a system of bridges, another kind of node operated by volunteers that pass traffic between other users and the Tor network. "Tor is getting really tricky for the Chinese to stop because getting a list of all the bridges is almost impossible," says Frank Rieger, who sits on the Tor board and is also involved with the CCC.
The more people that operate bridges around the world, the harder it will be for the Chinese to block Tor. (There's a guide to operating a Tor node at bit.ly/front2.) And the more Tor nodes there are, the better the network's performance will be. "So our wish is that people out there who can spare the bandwidth for open exit and middle nodes will contribute. It's not something that we can entirely do alone," explains Michael Horn, a networking expert who volunteers for the CCC.
Access to websites for journalists visiting China is less problematic. Mr Rieger explains that some news agencies have set up proxy servers - private computers outside China that journalists can connect to using an encrypted link. These computers act as a hopping-off point on to the public internet, giving the journalists unfettered net access. But the journalists must keep the addresses of these servers quiet in case the Chinese authorities block access to them.
Jonathan Zittrain, professor of law at Harvard and a chief investigator for the Open Net Initiative, argues that journalists visiting China aren't really the issue. News organisations outside the so-called Great Firewall of China should be trying harder to get their news through to the wider Chinese public rather than getting it to a few privileged reporters. "When those organisations put out their news, what effort are they taking to ensure that other people in China could get access to it?" he asks.
News agencies have lots of options, including mirrored websites, Tor-connected servers, having news articles converted to computerised speech and read over a Skype channel, and even producing a digest of the daily news that could be distributed on BitTorrent. The US Government's International Broadcasting Bureau has been using anti-censorship techniques for years to distribute the country's non-military international media, including the Voice of America, to countries whose governments would rather not have it. Other groups, such as Reporters Without Borders, are also heavily involved in promoting anti-censorship for news reporters (bit.ly/front4).
And that, ultimately, is the real battle. Visiting journalists are privileged players in China. They have the outside connections that they need to get unfiltered access.
But the CCC's real goal is to raise awareness. It is trying to mount a broader assault against Chinese net censorship that will continue after the Olympics, as citizens there continue to use Tor and public proxy servers in larger numbers.
This isn't a sprint to the finish - it's a long-distance race.