Ron Deibert, director of the Citizen Lab at the University of Toronto, has written a very useful article for the non-technical crowd on country-level internet filtering. "The Geopolitics of Asian Cyberspace", was published in the December issue of the Far Eastern Economic Review. For those who are new to the topic or would like a broad overview of the level of filtering that happens regularly, the corporate players facilitating that filtering, and a few projects that are trying to track censorship around the world, it's a good read.
Professor Deibert also showed up on NPR last week, talking about the Citizen Lab's new circumvention software, Psiphon. Unlike other circumvention tools like Tor or TorPark, Psiphon works by harnessing social networks and establishing individual nodes of "host" computers that allow internet access to known users; Deibert mentions in the interview that they had had 30,000 downloads of the software in the first week.
I wish the interviewer at NPR, Bob Garfield, had asked somewhat more pointed quesitons about specific differences between these tools and the theory of how they work -- there are a number of tools out there, and one may be more appropriate than another depending on geography, political situation, and your access to networks outside your own country.
With perfect timing, a correspondant pointed me to Peacefire founder Bennett Haselton's article on Slashdot last month that does some of that work. Bennett is generally annoyed with the attention the "politically correct" Psiphon has received in the media (as opposed to the more suspicious attention Peacefire's similar circumvention tool, Circumventor, received a few years ago). Beyond that, though, he provides a useful 101 on circumvention tools and how they work, as well as offering some commentary on how useless the tools are if a citizenry is apathetic about using them. He says:
This is not to downplay the enormous good that programs like Tor, Circumventor and Psiphon can do in bringing free speech to the people in censored countries who want it. But it's easy to forget that those often do not comprise a large part of the population....The moral is, no matter how much your movement believes in its efforts to help oppressed people, you can't just assume you'll be greeted as liberators (ahem).
Good to keep in mind.
Update: Professor Deibert pointed out another very useful article on Psiphon, this one which talks about Psiphon's aims -- that is, not a be-all end-all anti-circumvention tool, but a way for individuals to help other individuals through direct, personal connections.
Psiphon is not designed to solve all secure Web browsing dilemmas. Rather, it is a means by which those in uncensored countries can assist specific individuals in censored countries access blocked Web content -- without placing any technical (or personal security) burden on those individuals.
It's important to reiterate the point that, as with all technologies, this is not a one-size-fits-all game. There isn't an "unbreakable" anti-censorship tool; all of them can be defeated in one way or another. The crucial issue is to understand the strengths and weaknesses of the options well enough to choose one that offers the least risk given the environment.