Study claims more than 80% of 'dark net' traffic is to child abuse sites
A man types on a computer keyboard in Warsaw in this February 28, 2013 illustration file picture. REUTERS/Kacper Pempel/Files

Research claims that paedophilia sites using Tor’s ‘hidden services’ technology attract many more visits than drug markets and whistleblower sites


More than 80% of so-called “dark net” internet traffic is generated by visits to websites offering child-abuse material, according to a study of Tor “hidden services” websites conducted at the University of Portsmouth.

Researcher Dr Gareth Owen analysed traffic to sites using Tor’s technology to hide their addresses from search engines over a six-month period, in an attempt to understand what kind of sites were most popular.

He presented his findings at the Chaos Computer Congress in Germany, with Wired reporting on the research’s conclusion that while sites with paedophile material represent just 2% of the estimated 45,000 hidden services websites online at any one time, they account for 83% of visits to these sites once automated “botnet” traffic is removed from calculations.

Note: the study focuses on websites using Tor’s technology to hide themselves, rather than the surfing habits of individual internet users using Tor’s anonymising features. The latter are not spending 84% of their time visiting child-abuse websites.

“Before we did this study, it was certainly my view that the dark net is a good thing, but it’s hampering the rights of children and creating a place where paedophiles can act with impunity,” Owen told Wired, while describing the scale of traffic to these sites as “a huge shock”.

The study found that less than a sixth of hidden services sites that were online in March when the research started were still online in September when it concluded, suggesting a short average lifetime for these websites.

Owen also claimed that drug-related sites like Silk Road and Agora accounted for 24% of hidden service sites but 5% of overall traffic, while whistleblower sites like SecureDrop and Globaleaks are 5% of websites but “less than a tenth of a percent” of site visits.

Tor has responded to the research by questioning its accuracy, suggesting that the figures may include visits to paedophilia websites from law enforcement and anti-abuse groups, as well as denial of service attacks from hackers trying to take these websites down.

Tor’s executive director Roger Dingledine also stressed that hidden services websites only account for 2% of total traffic using Tor’s anonymising technology: a warning not to confuse websites hiding themselves with individual internet users using Tor to surf the web anonymously.

Dingledine added that hidden services do have less worrying applications. “There are important uses for hidden services, such as when human rights activists use them to access Facebook or to blog anonymously,” he told Wired.

Owen also expressed caution about the findings. “We do not know the cause of the high hit count and cannot say with any certainty that it corresponds with humans,” he said.

Even so, the study throws up new questions for Tor about how or whether it could help efforts to shut down paedophilia websites and identify their owners. Owen’s presentation at the Chaos Computer Congress included an examination of whether Tor might be able to block access to such sites.

• What is Tor? A beginner’s guide to the privacy tool

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