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A Taxonomy of Internet Censorship and Anti-Censorship Draft Version December 31 , 2010

Internet is supposed to be born free, yet it is censored almost everywhere, and severely censored in a few countries. The tug-of-war on the Internet between censors and anti-censors is intensifying. This survey presents a taxonomy on the principles, techniques, and technologies of Internet censorship and anti-censorship. It highlights the challenges and opportunities in anti-censorship research, and outlines a historical account via the lenses of news coverage in the past decade.