Some London airports are blocking access to websites distributing privacy-focused technology, including the Tor Project.
Torproject.org is the website of the non-profit that maintains the Tor anonymity software; tails.boum.org, which can be used to download the operating system Tails, is also blocked at both Heathrow and Stansted airports in London. I recently tried to access the Tor Project site in Heathrow, and sure enough, it was locked off.
Weirdly, neither Heathrow Airport nor Arqiva, the company the provides the airport's web-filtering service, could really explain why.
According to Heathrow Airport's FAQ on its wifi service, the network's third-party filtering software, "will automatically block access to certain types of websites and content which is deemed as inappropriate."
But how that applies to the Tor Project and Tails isn't clear.
Julia Weir, the head of PR at Heathrow Airport, told Motherboard in a phone call, "This is a standard product that we bought off-the-shelf from Arqiva."
"It doesn't seem to be something that our team here has nominated or anything like that," she said.
Steve Litwin, a service relationship manager at Arqiva, wrote in an email that websites are filtered by category, and are "based on the requirements of Heathrow Airport." Litwin didn't know which category torproject.org would fall into; Arqiva uses the services of cybersecurity company OpenDNS.
The OpenDNS categories include pornography, politics, and, perhaps most relevant for the Tor Project's website, "Proxy/Anonymizer" sites. According to OpenDNS's description, these are "sites providing proxy bypass information or services. Also, sites that allow the user to surf the net anonymously, including sites that allow the user to send anonymous emails."
"Do you know anyone who tried to download their web browser at the airport?"
Maybe Arqiva and its customers don't fancy letting someone download a piece of software that has the potential to totally circumvent their web-filtering. There are also, presumably, security requirements specific to airports.
The Tor Project was dismissive of the blocking. "Do you know anyone who tried to download their web browser at the airport?" Kate Krauss, a Tor Project spokesperson told Motherboard in an email.
Indeed, downloading any sort of software while on a public network—the traffic of which may be freely monitored or tampered with by anyone else connected to it—is not a great idea.
"We are concerned that CloudFlare is blocking access to the free internet for millions of Tor users; the idea that you may not be able to download our web browser from Heathrow while waiting for the airport shuttle is a bit less worrying," she continued.
Nevertheless, these blocks are an interesting example of the increasing use of censorship by web filtering in the United Kingdom.