UK exploring internet filter to block malicious software

The head of UK's newly formed cybersecurity agency says authorities are exploring the creation of a national internet filter to block malicious software and rogue websites, a proposal that has raised eyebrows among internet freedom advocates.

Ciaran Martin, the chief executive of the UK's new National Cyber Security Center, told a conference in Washington that his agency was working on a flagship project which would block Britons from coming into contact with "known malware and bad addresses."

According to a text of his speech published Wednesday, Martin said the system would allow consumers to opt-out - meaning that privacy and choice were "hardwired into our program."

Those assurances didn't sit well with some activists.

Martin said rogue websites would be blocked using DNS filtering, a venerable if clumsy censorship technique which prevents internet users from reaching a targeted server when they click a link or type out a web address.

But the technique is imprecise, occasionally blocking an entire website over a single rogue link. The London-based Open Rights Group worried that the Cyber Security Center's mother body, signals intelligence agency GCHQ, risked tampering with the integrity of the internet . The Financial Times newspaper described the project as a "Great British Firewall" - a reference to China's vast internet censorship system.

Joss Wright, of the Oxford Internet Institute, said that talk of a China-style firewall was overblown and that other forms of censorship - blocks on child pornography and copyright violators - were already around in any case.

"This is not the UK government turning into China or Iran and filtering the internet at its core," he said.

Still, Wright said there was always room for concern when a government agency began drawing up lists of sites to block.

"When you start building filter lists or censorship lists, things start getting censored," he said.