One thing that's missing in the teaching of computer science is history (think Ada) and there's no better example than the history cryptography, with famous ciphers going back to Caesar. It just gets juicer over the centuries, with the technical that details that normally might deaden your attention span plainly explained by the author. And now I think I have a handle on quantum cryptography. But as another review here noted, this book was published a few decades ago, so what have I missed?