>China relied on two U.S. companies--Cisco Systems and Juniper Networks--to help carry out its network upgrade, known as "CN2," in 2004. This upgrade significantly increased China’s ability to monitor Internet usage. Cisco also sold several thousand routers (IHT) used to censor web content, and "firm’s engineers have helped set it to spot ’subversive’ key-words in messages."
What's ironic about that? Cisco sold them networking equipment and the CCP used it to censor.