Bitfrost is a collection of security approaches developed by the OLPC group with the intent of substantially increasing system security. It’s an enlightening read:

http://dev.laptop.org/git/security/tree/bitfrost.txt

They cover everything from how to secure the BIOS to how to deter theft in the delivery chain for the actual laptops as they go from manufacture to a school in the boondocks.

On the name:

In Norse mythology, Bifröst is the bridge which keeps mortals, inhabitants of the realm of Midgard, from venturing into Asgard, the realm of the gods. In effect, Bifröst is a powerful security system designed to keep out unwanted intruders.

This is not why the OLPC security platform’s name is a play on the name of the mythical bridge, however. What’s particularly interesting about Bifröst is a story that 12th century Icelandic historian and poet Snorri Sturluson tells in the first part of his poetics manual called the Prose Edda. Here is the relevant excerpt from the 1916 translation by Arthur Gilchrist Brodeur:

Then said Gangleri: “What is the way to heaven from earth?”

Then Hárr answered, and laughed aloud: “Now, that is not wisely asked; has it not been told thee, that the gods made a bridge from earth, to heaven, called Bifröst? Thou must have seen it; it may be that ye call it rainbow.’ It is of three colors, and very strong, and made with cunning and with more magic art than other works of craftsmanship. But strong as it is, yet must it be broken, when the sons of Múspell shall go forth harrying and ride it, and swim their horses over great rivers; thus they shall proceed.”

Then said Gangleri: “To my thinking the gods did not build the bridge honestly, seeing that it could be broken, and they able to make it as they would.”

Then Hárr replied: “The gods are not deserving of reproof because of this work of skill: a good bridge is Bifröst, but nothing in this world is of such nature that it may be relied on when the sons of Múspell go a-harrying.”

This story is quite remarkable, as it amounts to a 13th century recognition of the idea that there’s no such thing as a perfect security system.

To borrow Sturluson’s terms, we believe we’ve imbued the OLPC security system with cunning and more magic art than other similar works of craftmanship — but not for a second do we believe we’ve designed something that cannot be broken when talented, determined and resourceful attackers go forth harrying. Indeed, this was not the goal. The goal was to significantly raise the bar from the current, deeply unsatisfactory, state of desktop security. We believe Bitfrost accomplishes this, though only once the laptops are deployed in the field will we be able to tell with some degree of certainty whether we have succeeded.

The name is also reminiscent of the ICE (Intrusion Countermeasures Electronics) that William Gibson made up for Neuromancer.