Protecting the $100 Laptop

Machine Shop columnist Simson Garfinkel looks at the surprising challenges of securing the OLPC project's low-cost computer for kids in developing nations

April 17, 2007 — CSO — The $100 laptop designed for the children of the developing world poses one of today’s most challenging sets of computer security problems. These laptops will be widely deployed to children who have no training in computer security, computer use or much of anything else, in some cases. They will belong to the children, go home with children and be customized by the children. And the laptops will provide Internet access using a new mesh network design that turns the laptops into wireless routers, allowing hundreds of children spread out across a village to share a single Internet connection.

Such a proposal would spell a security nightmare if these laptops were all running a stock copy of Windows, MacOS or even Linux. Hackers could steal a laptop, find a vulnerability and then write a worm to wirelessly hop from laptop to laptop, turning them all into the largest botnet that the world had ever seen.

Even worse, the One Laptop per Child project has enemies—from people who see $100 laptops as a waste of resources when many communities don’t even have clean water, to fundamentalists who are ideologically opposed to educating children with secular materials. Such enemies would almost certainly be motivated to create a piece of software to wipe the laptop’s operating system and turn it into a $100 brick.

Although botnets and bricks are a persistent fear of the laptop development team, the team is incorporating security measures into the design that are aimed at preventing both disasters from unfolding. Other security measures should reduce the incentives for thieves to steal the laptops, for parents to sell their children’s laptops and even for kids to change their “From” address and get their classmates in trouble.

The $100 laptop, officially called the XO-1 or Children’s Machine, is a marvel of engineering, but it isn’t a laptop that most adults would want to use. The laptop’s keyboard is a small plastic membrane stretched over a circuit board: It’s resistant to water, and there are no moving parts, and it’s definitely designed for children, not adults. The screen has a low-resolution color mode and a high-resolution black-and-white mode, in which it looks almost as good as paper but it’s the size of a paperback book. The computer’s CPU runs standard x86 instructions, but it’s slow—only a few hundred megahertz. The machine has just 128MB of RAM, 512MB of main flash memory, 1MB of BIOS flash and no hard drive. There are also three USB ports, a Secure Digital slot, a microphone and a camera.