Bi-directional Censorship from the Great Firewall of China

Tuesday, May 16, 2006  On May 12 Radio Free Asia reported some people outside China will get a "server connection has been reset" error message when they are trying to search some political keywords on Baidupedia. However, the Internet censorship is not just on Baidupedia because it's due to the keyword filtering technology on the Great Firewall of China.

One of the first people to find this filtering technology was Shi-Min Fang, a biochemist with a stance against ethical lapses in China. Fang, whose site "新語絲" has been blocked by the PRC government for years, had found that his Chinese name cannot be searched since last August if someone outside China uses an Internet search engine that is based in China. He posted a message to his own forum. A forum visitor gave him a method to verify what he found. By randomly choosing a website URL that is in China and adding banned keywords to that URL, the server connection will be reset without displaying the normal "page does not exist" error message. Take http://www.163.com/六四 for example, if you use that URL to link to the site when you are outside China, you will find the server connection will be reset.

A Chinese Wikinews reporter, Shi Zhao, also performed this test. He chose some political keywords such as "民主" (Democracy), "江泽民" (Jiang Zemin), "法轮功" (Falun Gong) and asked people to search on Google, Baidu and Sogou (a Chinese search engine developed by Sohu), and some Wikipedians from China, Taiwan and United States joined the test.

From the test, Chinese tester Shi Zhao found there is no problem to search such political keywords on Chinese search engines other than Google. And Taiwanese testers H.T. Chien, Alex S.H. Lin and American tester roc found they will get the "server connection has been reset" error message when they tried to search those political keywords on Chinese search engines other than Google.

From the test the testers believe that the keyword filtering technology on the Great Firewall of China is bi-directional. People outside China cannot visit any Chinese websites that have political keywords, and people in China cannot visit any websites outside China that has political keywords.

Baidupeida that went online this April is a service that provided by the Chinese Internet search company, Baidu, and its form is very similar to Wikipedia, which is blocked by the PRC government since last year. It would also allow users to join the editing on Baidupedia.

Sources

• 李建军. "百度百科主动切断搜寻敏感字眼的用户的连线" — RFA, 2006年5月12日
• 方舟子. "国内对敏感词的使用是双向的，国外的人也可以去体验一下" — 新语丝, 2005年8月12日