Cryptography and MOOC's

Instead of posting during the last month or two, I've been taking a couple of MOOC's (or massive open online courses).  If you haven't heard of these, check out Venture-Lab, Coursera, Udacity, and edX.  Rather than just posting a bunch of online lectures, universities now provide quizzes, group work, forums, and tests.  MOOC's are taught by top professors at top schools (though being a top professor has nothing to do with being a good teacher).  And, if you care about it, you can get a certificate of completion.

It's not yet clear what the future holds for MOOC's.  Some predict that, in a few years, only a handful of universities will remain.  Others think MOOC's are antithetical to the selectivity top universities cultivate and thus can't be sustained.  In any case, I'm taking as many as I can while they're still free.  If you don't care about getting credit, they're a great way to keep learning.

I never took a cryptography class in college, so I enrolled in Dan Boneh's.  Basically, cryptography is all about taking strings of 0's and 1's and then XORing them with a key (also made up of a bunch of 0's and 1's) in order to get a cipher text.  The bulk of cryptography, as a science, is determining what counts as a good key and how two or more people can share keys in a secure manner.

While it was interesting to delve into number theory and modulo arithmetic, the point Boneh hammers over and over again is that you should never develop your own cryptographic solution, because you will screw it up.  Many commercial applications make silly mistakes; you're certain to forget something.

For this reason, I quickly became bored of the course.  The abstract problem of designing and cracking keys is completely different from the real-world problem of securing applications.  In college, there was no limit to the amount of useless theory I was willing to learn.  But now there's a premium on my time.  I could be learning a thousand other things in other MOOC's, after all.

I have found that this flexibility is the main benefit AND drawback of MOOC's.  You're free to come and go as you want, which became a problem in a group project I completed in my finance course.  Two of the four group members dropped out, and I wasn't much help either, leaving the bulk of the work for one person.  MOOC's promise something akin to the college experience of making friends from around the world, but there is no incentive to stick with it when the going gets tough.

I will definitely continue to use MOOC's as long as they are available.  I started a course in networking today.  I think it is unlikely that MOOC's will upset established universities, but they will increase the (already high) pressure on colleges--especially lower-ranked private schools that already offer a questionable return on investment.  Educators of the future will have to be able to teach large numbers of students in ways that work.  I'm happy to be part of the experiment.