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censorship
(Merriam-Webster, 2012)
Act of changing or suppressing speech or writing that is considered subversive of the common good.
Online Censorship
On a global playing field, censorship takes on a whole new meaning. Restricting access to information and monitoring outgoing content is more common than most people realize. The censorship researchers at Tor work to build tools that stay ahead of censorship tactics and provide open channels of communication for everyone online. The Tor team builds partnerships to raise awareness and educate people about the importance of privacy online and freedom of speech online.
Internet surveillance is common and easy.
Some censorship circumvention designs use only one layer to hide connections.
Unfortunately, one layer (as with a proxy) is easy to attack.
Parts of the network
could be monitored.
Bob’s connection could be
watched or he could be
working for the regime.
Alice could be watched as she connects to Bob.
Proxy could be eavesdropping or be monitored.
How Tor Works
Freedom & Privacy Online
Alice encrypts her web page request to Bob three times and sends it to the first relay.
The first relay removes the first encryption layer but doesn't learn that the web page request goes to Bob.
The second relay removes another encryption layer and forwards the web page request.
The third relay removes the last encryption layer and forwards the web page request to Bob, but doesn't know that it comes from Alice.
Bob doesn't know that the web page request came from Alice, unless she tells him so.
https://www.torproject.org/