Telex, the anticensorship network infrastructure

Researchers from the University of Michigan (US) and Waterloo (Canada), have developed a new anti-censorship tool called Telex to stop Governments from blocking websites, it can help people to access the most commonly blocked websites, at the moment Facebook, Google, Youtube, Twitter and, the list can be expanded according to needs.

One of the main differences of Telex in comparison to a tor proxy is that it does not alert people watching traffic that a censorship circumventing tool is being used and unlike proxy sites, it can not be blocked. After a user has installed Telex software in his computer when he wants to visit a censored website a secure SSL connection is established to a non blacklisted server outside the censor’s network, that connection is secretly marked as a Telex request using a hidden cryptographic tag in the headers, data requests go through various ISPs routing traffic, if some of those ISPs implement Telex stations to detect hidden cryptographic messages in the headers, they can then serve banned content to a user without anyone knowing.

Telex stations are able to see what page you are requesting, this tool will not make you anonymous but it can be used in conjunction with a tor proxy or VPN. One possible counter attack against Telex would be for a censor country to run its own Telex station but because the requests use steganography with public/private encryption keys, without the real private encryption key they would be unable to detect or block Telex tagged requests, the idea would be to keep a central Telex authority banning certain ISPs or to change the private encryption key every 5 minutes only with those who have been whitelisted.

Telex anticensorship network

Telex anticensorship network

In order for Telex to work it is necessary the participation of ISPs which means some kind of state level support, at the moment there is a single ISP at the researchers lab that works and it can be easily blocked, no real ISP has implemented Telex as of yet,  the software has only been released for testing and it is unsafe for real world use, the researchers have already managed to make it work from within China to stream banned YouTube videos.

Visit Telex homepage

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