Friday, 11 November 2005

Seal and hard drive

I saw the seal again today. This time he (she?) was swimming. He ducked down under water after a few seconds, and reappeared a few minutes later and 200 yards downstream, just a black blob on the waves. Very nice.

Slashdot has a discussion on how long it would take for the police to decrypt an encrypted hard drive. This was one of the justifications offered for 90-day detention. Bottom line: 90 days is a slight underestimate. Good encryption cannot be cracked within the lifespan of the known universe, unless you can guess the password. Encryption is one of the subtlest parts of computer science, about which I know little, but the fundamental deal is fairly straightforward: every time you add a character (say just a-z) to your password, you multiply the number of potential passwords, and the time it takes to guess the password by brute force, by 26. Go type "26 x" into your calculator and hit "=" a few times. See?