The porn – um, "privacy" – modes in modern browsers do a great job of letting workers browse Facebook under the noses of employers with strict Web policies, but privacy modes don't do squat when a heavy-handed regime blocks access to specific websites. Freedom-loving webizens in freedom-hating countries have long turned to TOR as their onion-routing proxy of choice to get around governmental roadblocks, but researchers at the University of Michigan have developed a new system that could help Iranians and other censored Web users access "immoral" websites like Twitter and CNN.
Dubbed Telex, the system doesn't actually involve pointing users towards individual proxies. It works by attaching Telex devices to routers in various choke points throughout the Internet's architecture.
Ars Technica reports
that users would then identify which traffic they want proxied where; they would then point their browser to a standard website, and the Telex routers would pick out the traffic en route and redirect the browser to the desired website. Censors would never know the switch even happened.
Of course, the Telex tag couldn't be obvious or those dastardly dictators would just block all communications that contained the rerouting command. The researchers got around that by exploiting the nature of TLS handshakes that are used to transfer encrypted traffic across the Web. If you indicate that you want a Telex redirection, Telex's public key creates a steganographic tag for the traffic and inserts it into the TLS handshake's "nonce," which is normally a random string. To throw off would-be censors, the Telex tag also appears random, but the code would be recognized by the Telex servers.
Placing Telex devices on choke points around the Web seems pretty friggin' expensive to us, and there wouldn't be much incentive for commercial carriers to implement the proxy service. Telex won't work without widespread adoption, so what's the research team's implementation plan? They're hoping to get governments to foot the bill -- some day -- in the further interests of democracy.
If you're the kind of person who likes page after page of technical details, you can check out the
entire plan here