Cryptosmith

A SANS Handler Notebook entry by Toby Kohlenberg reports on data leakage in cloud computing, and links to a terrific paper from some UCSD/MIT people: Ristenpart, Tromer, Shacham, and Savage.

If we set the wayback machine to the early 1970s, we find a paper by Butler Lampson about something called the confinement problem. It’s the same thing. Ristenpart et al pick up some of the threads (like noninterference) though their paper doesn’t point all the way back to Lampson.

This is a hard problem to solve. The only defense right now is if attackers lack the motivation to exploit it.

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Marc Ambinder of the Atlantic recently blogged about alternative Blackberries that President Obama may carry. Some people might wonder why this is such a big deal. Ambinder notes that “Government Blackberries” can handle classified information “up to Secret” but that you need a Sectera Edge from General Dynamics to do anything (voice only) at Top Secret.

Words of the President are obviously valuable, whether voice or text. Even if we ignore spies, think about the interest they carry for news reporters, government contractors, political operatives, and other presumed patriots. So, to start with, we have to ensure that the President’s words are only released when he decides to do so.

The government has established several strategies for protecting information assets. While we don’t necessarily know what they’re doing in the White House, we can make some educated guesses. The problems, and solutions, revolve around multilevel security, also called MLS. Continue Reading »

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I have moved some material about multilevel security (MLS) and ‘cross domain systems’ (CDS) onto this web site from my old Cryptosmith site. I’ve also included some brief comments on CDS. There is also a link to my MLS Introduction, which I will be updating and migrating to this site over the next few months.

I’m not collecting comments on static pages if I can help it, so if you have the need to comment on my MLS or CDS materials, post the comment here.

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(back to MLS Introduction)

• Labeled Networks
• Multiple Independent Levels of Security (MILS)
• Sensor-to-Shooter
• Non-Defense Applications Similar to MLS

(previous: The Assurance Problem)

(next: Conclusion)

As computer costs fell and performance soared during the 1980s and 1990s, computer networks became essential for sharing work and resources. Long before computers were routinely wired to the Internet, sites were building local area networks to share printers and files. In the defense community, multilevel data sharing had to be addressed in a networking environment. Initially, the community embraced networks of cheap computers as a way to temporarily sidestep the MLS problem. Instead of tackling the problem of data sharing, many organizations simply deployed separate networks to operate at different security levels, each running in system high mode. Continue Reading »

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