China's Smarter Filters

In 2005, the Open Net Initiative (ONI), a partnership of the Berkman Center at Harvard Law School, the University of Toronto's Citizen Lab, and Cambridge and Oxford Universities, published a report on Internet Filtering in China. Compared to an earlier Berkman Center study in 2002, ONI found most Web sites were now more accessible. The two exceptions were sites which mentioned the outlawed spiritual movement Falun Gong, and the Tiananmen Square uprising. Both subjects were more heavily blocked in 2005.

China is "getting better at filtering," says Ben Edelman, co-author of the earlier Berkman Center study. In 2002 China had to resort to blocking entire IP addresses or domain names. Now its censors can target specific pages within a domain, based on blacklisted keywords in a page or URL.

But China's way of blocking Web content continues to keep users in the dark about whether they are being censored. Some other countries that filter the Web send users to a "block page" notifying them that the requested page has been prohibited. Not in China, explains Bennett Haselton of Peacefire.org, a Web site dedicated to free-speech online: "If you try to access a blocked IP address it is simply denied. If you try to access a page that contains a banned word or phrase, the connection will be cut off and you won't be able to connect to that site for a certain period of time. With repeat violations the 'penalty' block time is longer."

Google cited this user experience with Google.com in China as a reason for starting up its China-based, and censored, Google.cn.

 

The Many Layers of China's Filtering

Google.cn is only a piece of what Nart Villenueve of the Citizen Lab at the University of Toronto calls China's "web of controls" comprising state agencies, private companies and even cyber cafes.

Government filtering occurs at the nine Internet Access Points (IAPs) where China connects to the global Internet. These IAPs provide bandwith to hundreds of Internet Service Providers (ISPs), which must register with the state and censor the Web sites on their services. "It's not a single organization building these lists [of blocked addresses, domains and keywords]," says Villenueve "Each ISP is required to block bad Web sites, but they decide themselves how to implement this requirement."

Cyber cafes are also required to register and monitor users, and citizens with home Internet access must register with local authorities. According to Villenueve, these layers of censorship serve China's ultimate goal: "to get users to censor themselves."

Bennett Haselton of Peacefire.org thinks many Chinese are ambivalent, if not nonplussed, about Internet censorship. "Some Chinese residents, and even expatriates that we've talked to, were a bit annoyed when we wanted to help Chinese people get uncensored Internet access. They either said they supported the government or they didn't care."

 

Tools for Circumventing the Firewall

Haselton's Peacefire.org distributes a program called Circumventor, enabling computers outside of China to serve as "proxies" through which Chinese can surf the Web uncensored. Peacefire also sets up public proxy servers on a "cheapo hosting service" and sends the server addresses to users in China. But these public servers usually last only a few days before being blocked.

Editor's Note: Circumventor is a Windows installer of the CGIProxy script written by James Marshall.

Freegate is another proxy server program created by Bill Xia, a Chinese expatriate and Falun Gong follower. Nart Villenueve's Citizen Lab is working on a similar program called Psiphon. TOR, hosted by the Electronic Frontier Foundation, takes a different approach. It lets users surf anonymously by bouncing Internet traffic around a "network of volunteer servers around the world," explains developer Roger Dingledine. "We built it to deal with security and civil liberties issues right here in the U.S."

With the exception of Psiphon, which receives funding from George Soros' Open Society Institute, all these programs have received some support from the U.S. government. Peacefire and Freegate receive funding from the Voice of America and TOR began as a project of the U.S. Naval Research Lab.

 

Who's Using Them?

It is unclear how many Chinese are using these anti-blocking, anti-tracking programs. Bill Xia claims Freegate is used by 100,000 Chinese. Haselton says Circumventor is downloaded about a dozen times daily and each proxy server it generates could be used by hundreds of Chinese. But there's no way to know the exact number and given even the most optimistic estimates, users of these programs represent a tiny fraction of China's 111 million Internet users.

It is also unclear how exactly Chinese are using these programs. Nart Villenueve once shut down a public proxy server because users were downloading movies and pornography through it. Bill Xia says journalists use Freegate in their work, and that ordinary Chinese do read about politics, but many view it more as gossip than news. Then again, notes Ben Edelman, "A lot of Americans don't read political news."

Regardless of how Chinese use these programs, Edelman cheers the proliferation of anti-censorship software because it keeps China's Web censors on their toes: "The more [of these programs] there are, the less likely that some Chinese network administrator will go to the bother of trying to shut a particular program down."