Wikipedia writes: "The Golden Shield Project ..., sometimes referred to as the Great Firewall of China, is a censorship and surveillance project operated by the Ministry of Public Security (MPS) of the People's Republic of China."
http://en.wikipedia.org/wiki/Golden_Shield_Project

Another Wikipedia article states: "Cisco has been criticized for its involvement in censorship in the People's Republic of China. ... According to author Ethan Gutmann, Cisco and other telecommunications equipment providers supplied the Chinese government with surveillance and Internet infrastructure equipment that is used to block Internet websites and track Chinese on-line activities. Cisco says that it does not customize or develop specialized or unique filtering capabilities to enable governments or regimes to block access to information and that it sells the same equipment in China as it sells worldwide."
http://en.wikipedia.org/wiki/Cisco#China

Now, a leaked presentation by Cisco shows slides which talk about the golden shield. One slide uses direct quotes from a Chinese government official, who talks about "Guarantee the security and services of public network" and "Combat 'Falun Gong' evil religion and other hostiles. The slide immediately following that slide is titled "Cisco Opportunities", talking about planning, construction, training and maintenance.

http://blogoscoped.com/files/cisco-slide-agenda.png
http://blogoscoped.com/files/cisco-slide-1.png
http://blogoscoped.com/files/cisco-slide-2.png

The PDF and more information can be found in Wired's article on this:
http://blog.wired.com/27bstroke6/2008/05/leaked-cisco-do.html

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