Tried surfing on your mobile phone lately? If so, you may have found that quite suddenly you can't visit certain websites until you've reassured your network that you are over 18.





Having seen this story about the issue, I thought I would try myself to visit one of the sites mentioned. It is called Jalopnik, and is all about cars - not a particularly racy subject, you might think.

But sure enough, when I visited it from my phone on O2's 3G network, up popped a message warning me that I needed to be over 18 to see it. I now need to contact my account administrator, whoever that is.

Next stop was the O2 blog which explains:

"Over the last few months we've been gradually migrating our customer base onto a new age verification platform. We've completed, which will ensure all our Pay & Go and Pay Monthly customers are protected by the age verification system."

O2 - which is not the only network doing this - says the policy is designed to give reassurance to parents whose children are now using smartphones. Fine, but surely a contract customer like me has to be over 18 so why am I having my surfing censored?

The network explains that some parents are now buying monthly contracts for their children, so it's not safe to assume that phones are being used by adults.

But who decides which sites get blocked, and why does a site about cars end up ringing alarm bells? Apparently the networks have set up something called the Independent Mobile Classification Body (PDF) to categorise websites - and its work is not yet perfect. Sites which have been wrongly categorised will be "whitelisted" once mistakes are pointed out.

Getting your age verified by your network is a bit of a faff - you have to pay a pound via your credit card, though you then get £2.50 credited to your mobile account. It's all causing a deal of grumbling from the network's customers.

"We do apologise for the inconvenience but it's a simple process aimed at protecting children," an O2 spokeswoman.

This whole policy has wider implications for the debate about policing the web, and protecting children. Social networks like Facebook have said age verification is a really difficult thing to do - and that means they can't know whether users are under the age at which they are permitted to join.

But now the mobile networks have shown that there is at least a way to verify parental permission via a credit card, pressure may grow on other sites to do more to check that people are who they say they are.

