Culver City (CA) - The One Laptop Per Child (OLPC) group will be installing remote-kill switches to deter people from reselling their cheap laptops. The OLPC costs around $130 to produce which could entice some residents of poorer third-world countries to mark up prices and sell them for a tidy profit. Walter Bender, OLPC's president of software and content, has told Reuters that the laptops can be remotely shut down to prevent them "from being sold on the black market."
Bender wasn't more specific about the kill switch, but the OLPC uses the Bitfrost security platform which is copiously documented here.
When the OLPC is booted up, an anti-theft process runs and calls the country's home OLPC server once a day. This process cannot be terminated, even by the root user, and sets the current time along with obtaining a cryptographic lease to run for a certain time . Each country can set its own lease times.
When a laptop is stolen, its serial number is entered into the centralized server. Upon the next Internet connection, the laptop will be forced to do a hard shutdown and will lock. Enterprising thieves that try to avoid the Internet will find it pretty darn difficult because the OLPCs are wireless mesh routers and try their best to connect. When the lease time is up, the laptop will shutdown anyways.
Of course we expect hackers to try their best to break through this "remote-kill switch", but the OLPC group is probably just trying to prevent opportunistic reselling of the computer in areas where a few hundred dollars could feed a family for a few months. The group is also prevent the theft of components by making them difficult to remove and according to the group, "All valuable parts of the XO laptops are soldered onto the motherboard."