In the Moment

I stood at the podium, trying to get the computer and projector to communicate. It wasn't happening. "I hate when this thing doesn't work," I muttered, not caring if the class heard me. As I studied the computer, one of my students, Archie, in a deadpan voice says, "If only we could get a computer expert in here." The title of the course is Computer Applications: Fluency with Information Technology...I am the computer expert. Continuing to glance between monitor, projector and screen, I wait a few moments while the class holds it's collective breath. "I'm going to pretend I didn't hear that," I say humorously, and the class lets out a relieved laugh.

Later, we're talking about sending secure e-mail. In case you didn't already know, all of the e-mail you send is sent in plain text, easily snooped and easily read by anyone with the ability to purloin an electronic letter. If you need to send sensitive information, you don't want to do it unless you've secured your e-mail with some kind of encryption. I had prepared an example already, but I couldn't help myself; Archie had left too good an opening.

"So, " I say earnestly, "after insulting his instructor so thoroughly, Archie realizes that he's going to need to bribe her if he wants a decent grade in this class." The class laughs uproariously, and Archie accepts the ribbing graciously. "But he can't just do that outright; he needs to send an encrypted e-mail because he doesn't want to get caught." Luckily, I explain, I have a security certificate which enables other people to send me encrypted e-mails. Using my public key, Archie encrypts his message and sends it to me. Anyone who snoops the e-mail will only see a jumble of nonsensical characters. When I get the e-mail, I use my private key to decode it and read it.

"Archie's offered me a million dollars for an A," I say. Then I pause. "But that's nowhere near enough. I need at least a hundred million, but I can't send him an e-mail that says that, because Archie doesn't have a security certificate so I can't send him an encrypted e-mail. So instead, I have to say something like, 'You're missing two zeros' so no one knows what I'm talking about. "

As I finish this statement, and get ready to explain about digital signatures and how they'll make e-mail tampering evident, another student pipes up, "You've put a lot of thought into this. Have you done this before?"

Touche.