When I was in the Air Force in the mid-80s, I had a Top Secret security clearance. In the process of obtaining that clearance, we were given training on how to keep secrets safe. One of the lessons that stuck with me over the years was a concept the Air Force called “eefi.” An eefi is an Essential Element of Friendly Information. It’s not classified or even necessarily important by itself. However, if the bad guys collect enough eefis, they can determine something important from them. For instance, if you’re planning a surprise party for someone and she calls to ask you to go to dinner on the evening you’ve planned the party, it’s no big deal if you her that you have other plans that night. It’s not even significant if you won’t tell her what those plans are. If she starts calling other friends and is repeatedly told they have other plans that they aren’t willing to tell her about, she’s going to be able to put together that something is going on. That’s how eefis work.
So imagine how easy it would be to determine an incredible amount of information about a person by examining all of the eefis that are available about them. This is the heart of the privacy scare that is connected to the Internet. Lots of little bits of information about all of us floats around in computers. If somehow one entity could pull all of that information together, they’d be able to infer a great deal about us. The reality is that most of us just aren’t that interesting. Our bigger concern should be that the eefis about us are accurate because one wrong item can make a lot of others “fit the picture.” The Feds thought Elliott Spitzer was involved in some kind of money laundering when they busted him for pandering.