Internet Filtering in China in 2004-2005: A Country Study

April 13, 2005

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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. It comprises multiple levels of legal regulation and technical control. It involves numerous state agencies and thousands of public and private personnel. It censors content transmitted through multiple methods, including Web pages, Web logs, on-line discussion forums, university bulletin board systems, and e-mail messages. Our testing found efforts to prevent access to a wide range of sensitive materials, from pornography to religious material to political dissent. Chinese citizens seeking access to Web sites containing content related to Taiwanese and Tibetan independence, Falun Gong, the Dalai Lama, the Tiananmen Square incident, opposition political parties, or a variety of anti-Communist movements will frequently find themselves blocked. While it is difficult to describe this widespread filtering with precision, our research documents a system that imposes strong controls on its citizens' ability to view Internet content.

Unlike the filtering systems in many other countries, China's filtering regime appears to be carried out at various control points and also to be dynamic, changing along a variety of axes over time. This combination of factors leads to a great deal of supposition as to how and why China filters the Internet. These complexities also make it very difficult to render a clear and accurate picture of Internet filtering in China at any given moment. Filtering takes place primarily at the backbone level of China's network, though individual Internet service providers also implement their own blocking. Our research confirmed claims that major Chinese search engines filter content by keyword and remove certain search results from their lists. Similarly, major Chinese Web log ("blog") service providers either prevent posts with certain keywords or edit the posts to remove them. We found also that some keyword searches were blocked by China's gateway filtering and not the search engines themselves. Cybercafés, which provide an important source of access to the Internet for many Chinese, are required by law to track Internet usage by customers and to keep correlated information on file for 60 days. As a further indication of the complexity of China's filtering regime, we found several instances where particular URLs were blocked but the domain was accessible, despite the fact that the source of content appeared consistent across the domain - suggesting that filtering may be conducted at a finer level in China than in the other countries that we have studied closely. Moreover, China's Internet filtering appears to have grown more refined, sophisticated, and targeted during the years of ONI's testing.

China's intricate technical filtering regime is buttressed by an equally complex series of laws and regulations that control the access to and publication of material online. While no single statute specifically describes the manner in which the state will carry out its filtering regime, a broad range of laws - including media regulation, protections of "state secrets," controls on Internet service providers and Internet content providers, laws specific to cybercafés, and so forth - provide a patchwork series of rationales and, in sum, massive legal support for filtering by the state. The rights afforded to citizens as protection against filtering and surveillance, such as a limited privacy right in the Chinese Constitution, which otherwise might provide a counter-balance against state action on filtering and surveillance, are not clearly stated and are likely considered by the state to be inapplicable in this context.

China operates the most extensive, technologically sophisticated, and broad-reaching system of Internet filtering in the world. The implications of this distorted on-line information environment for China's users are profound, and disturbing.

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Last updated

April 16, 2015