U.S. Tech Companies Fighting China's Firewall

U.S. tech companies are caught in the middle of an escalating battle between China’s increasingly active Internet censors and the free-speech activists determined to thwart them. Activists outside of China say they are disguising Internet traffic banned by Beijing -- which includes anything from social networks such as Facebook and Twitter, to Gmail and news websites -- by tunneling it encrypted through cloud servers run by major U.S. companies.