Password entropy

As part of some 'NetSafe' training, I was shown this lovely xkcd cartoon http://xkcd.com/936/ .   Password entropy. That's a good way of putting it. The statistical mechanics definition of entropy would be k ln W, where k is Boltzmann's constant, W is the number of permutations possible, and ln is 'the natural logarithm'. Higher […]

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Don’t trust the machine

Back to blogging, after a nice holiday in Taranaki dodging the rain showers (and, as it turned out, the volcano, which we never even got a glimpse of) and a frantic week of lab work while the undergraduates were away.  Both were very interesting, but it's the lab work I'll talk about here.  Something that […]

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Explaining the blatantly obvious

I've had a few difficulties in some discussions with students recently. It comes down to this: "How do I explain something that is so blatantly obvious it doesn't need explanation?"  The problem really is that a particular concept can be obvious to me, but not obvious to a student. The danger is then that, in […]

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Apparent forces

A couple of weeks ago I had the misfortune to be on a bus which had an accident. I wasn't hurt, because I was safely seated, which is more than I can say for one unfortunate passenger who was still on his way to his seat at the time. It wasn't a high-speed event – […]

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