Online markets trafficking in illicit goods, such as the now defunct Silk Road, are probably the best known examples of destinations on the dark web, hidden services that can’t be visited with a conventional web browser. But the dark web also hosts legitimate sites with an interest in preserving user privacy, such as the nonprofit investigative news service ProPublica, which launched a hidden service last week (Jan. 13).
Facebook has had a dark-web presence for more than a year. In October 2014, the social network set up an address on Tor, a hidden-service network that disguises the identity of users and requires use of a special web browser to visit sites. (Sites on Tor have addresses that end in “.onion.” Here’s Facebook’s .onion address.)
Facebook isn’t releasing usage figures, but it says that a “sizeable community” of its users actually visit it on Tor—sizeable enough that Facebook has now released a feature that lets users access its dark web site via Android smartphone.
Facebook’s Tor site is one way for people to access their accounts when the regular Facebook site is blocked by governments—such as when Bangladesh cut off access to Facebook, its Messenger and Whatsapp chat platforms, and messaging app Viber for about three weeks in November 2015. As the ban took effect, the overall number of Tor users in Bangladesh spiked by about 10 times, to more than 20,000 a day. When the ban was lifted, the number dropped back to its previous level.
The spike in Tor use in Bangladesh was highlighted by Roger Dingledine, a founder of the organization that maintains the open-source Tor software, during a talk in Berlin. “There have been a whole heck of a lot of people there learning about these privacy things that can get around local censorship,” he said.
Governments can block websites and other internet services in a variety of ways, from filtering domain names to targeting specific keywords or IP addresses. Dingledine also highlighted an uptick in Tor usage in Russia, where the government maintains a list of blocked sites that has included Wikipedia. In May 2015, Facebook was warned that it could be blacklisted for not handing over data on Russian users.
But we still don’t know for sure if users are turning to Tor just so they can get to their Facebook accounts. As Dingledine pointed out in his talk: “Our data is public and open and we like sharing it; they don’t actually share their data, but one day it would be cool to see … [data on] users shifting from reaching Facebook directly to going over Tor.”
Facebook told Quartz it doesn’t presently provide traffic statistics or other data for its Tor hidden service.