How governments have tried to block Tor

[skynet]

Privacy should not be such a struggle, but it is. This video (below) is a very interesting presentation from people that are doing an incredible job helping everyone to keep their privacy.

What is Tor?
Tor is free software and an open network that helps you defend against a form of network surveillance that threatens personal freedom and privacy, confidential business activities and relationships, and state security known as traffic analysis

Why Anonymity Matters
Tor protects you by bouncing your communications around a distributed network of relays run by volunteers all around the world: it prevents somebody watching your Internet connection from learning what sites you visit, and it prevents the sites you visit from learning your physical location. Tor works with many of your existing applications, including web browsers, instant messaging clients, remote login, and other applications based on the TCP protocol.

Learn more at: Tor

"Iran blocked Tor handshakes using Deep Packet Inspection (DPI) in January 2011 and September 2011. Bluecoat tested out a Tor handshake filter in Syria in June 2011. China has been harvesting and blocking IP addresses for both public Tor relays and private Tor bridges for years.

Roger Dingledine and Jacob Appelbaum will talk about how exactly these governments are doing the blocking, both in terms of what signatures they filter in Tor (and how we've gotten around the blocking in each case), and what technologies they use to deploy the filters -- including the use of Western technology to operate the surveillance and censorship infrastructure in Tunisia (Smartfilter), Syria (Bluecoat), and other countries. We'll cover what we've learned about the mindset of the censor operators (who in many cases don't want to block Tor because they use it!), and how we can measure and track the wide-scale censorship in these countries. Last, we'll explain Tor's development plans to get ahead of the address harvesting and handshake DPI arms races."