How to keep your data secure for up to 149 trillion years..

In light of recent media focus a number of Government Agencies are reportedly busily encrypting their laptops using the AES 256-Bit encryption standard. I thought I’d have a look to see how strong AES actually is. Here’s what Apple had to say about AES 128-bit used on their older ⁽¹⁾ OS X 10.4 Tiger operating system:

“AES gives you 3.4 x 10³⁸ possible 128-bit keys. In comparison, the Digital Encryption Standard (DES) keys are a mere 56 bits long, which means there are approximately 7.2 x 10¹⁶ possible DES keys. Thus, there are on the order of 1021 times more possible AES 128-bit keys than DES 56-bit keys. Assuming that one could build a machine that could recover a DES key in a second, it would take that machine approximately 149 trillion years to crack a 128-bit AES key.

(To put that into perspective, the universe is believed to be less than 20 billion years old.)”

^{(1) Apple’s more recent OS X 10.5 Leopard offers AES 256-bit encryption out of the box.}

Updated March 6th 2008:

A disturbing follow-up about this topic on this week’s BBC’s Digital Planet podcast, click here to listen now or right-click here to download and listen later (12MB – MP3)

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