Shining a light on the 'darknet': How online paedophiles stay hidden

Paedophiles and other criminals are increasingly turning to what is known as the 'darknet' in efforts to keep their identity hidden while browsing horrific images of child abuse.

The darknet allows users to communicate and share files through encrypted systems which keep them anonymous.

And with experts predicting it could make up as much as 96 per cent of online content, the government has warned that only a major international effort will begin to tackle the problem.

Evidence suggests it is being used by an increasing number of paedophiles after action by major internet firms meant search engines blocked all requests linked to child abuse terms, leading to an 80 per cent reduction in searches and the removal of around 40,000 graphic abuse images.

Figures from the National Crime Agency (NCA) show that the number of internet users in the UK using the darknet has increased by two-thirds in recent years, up to around 20,000 a day last year alone.

And with government figures suggesting 50,000 suspected paedophiles active in the UK, and new measures being introduced to tackle people who not only produce, but access, abuse images, the fear is that more will resort to these secret networks.

So what is the 'darknet'?

Essentially, it is the 'hidden internet'. Special software allows users to e-mail, share and store files through encrypted and anonymised networks, which - while connected to the general internet - are not available via the usual major search engines.

It works by encrypting the user's connection requests, before bouncing them through several 'nodes' - each of which only knows the identity of the one before it, and which erases that information periodically - before connecting to the server at the other end.

Websites set up under the service are only accessible by people using the software, and are not accessible to anyone else, meaning there is no danger that the average user will stumble upon the site by accident.

Estimates vary, but experts say the darknet - also known as the 'deep web' - could make up around 96 per cent of the total number of pages available online.

It is dangerous?

It can be - and extremely so.

For one thing, as it is even more unregulated than the unpredictable part of the web we know about, even legitimate users leave themselves open to exploitation, hacking and blackmail.

Its anonymous nature means it is particularly attractive to those who do not want others to know what they have been up to - and usually, that means it's illegal.

Child abusers can upload horrific pictures and videos freely, while others can download them and pass them on, without having to worry about whether their IP address is giving them away.

And it's not just used by paedophiles, either.

Criminals can use the darknet to find, share and sell assassination deals, credit card scammers, forged documents, fake cash, weapons, drugs and other illegal pornography. The notorious website SilkRoad, which was taken down last year after an FBI raid, is an example of one such marketplace.

Is there a bright side?

Absolutely. It isn't a crime to access the darknet, and in fact is heralded by many experts as being a bastion of free speech in a world where security agencies are able to access most electronic communication with ease.

It allows whistleblowers to voice their concerns to the press or other relevant parties without fear of their identity being exposed. The New Yorker magazine has even built its own corner of the darkweb for this very purpose.

It allows freedom fighters in war-torn countries to contact one another, and gives a voice to people living under strict censorship rules to express themselves.

It means, for example, that homosexual people can explore their identity in countries where they may be jailed or even killed for being gay.

Some military forces even use certain 'Hidden Services' to create online secure command and control centres when in the field.

What can be done?

Prime Minister David Cameron has unveiled plans for a new taskforce, composed of experts from the NCA and intelligence agents from GCHQ, to start trawling the darknet to try to dig out the child abusers who exploit its services.

The unit will be responsible for analysing the huge quantities of child sexual exploitation imagery hidden in the depths of the darknet, not only to remove the content itself, but to track down those who upload and access it too.