I remember when I was 15 years old, a geeky and paranoid associate rang me. He was one of those high-strung teenage phreakers who think they’re on the FBI’s most wanted because they strip a few wires from a telephone pill box outside someone’s house at 2 in the morning and make calls to Russian phone-sex lines.
Anyway, he rings me and the first thing he says is, “Do you have pretty good privacy?”
I looked around to ensure my father wasn’t listening in and whispered in conspiratorial tones, “Dad’s in the room, but I don’t think he gives a shit.”
It turned out that he was actually asking if I have Pretty Good Privacy, one of the earliest publicly available encryption tools. Presumably he wanted to send me a top-secret list of Bulgarian joke lines or something.
PGP still exists, and I guess there’s still a group of people out there using it, though apparently the company selling PGP has shifted to corporate cybersecurity. Even if you send an encrypted email, of course, the email could be saved, copied, the code cracked at some later date, perhaps. The fact is, once you put something out there in the internet, as Vanessa Hudgens learned, that’s one doodle that can’t be undid.
Or could it? Computer scientists at the University of Washington have put together a project called Vanish. What Vanish does is allow you to encrypt data with an encryption key that – not unlike the plot of a Final Fantasy game – is broken into many pieces and scattered across the internet. At the other end, the intended recipient can use Vanish to – not unlike the spikey-haired sword-gun-combination-wielding hero in the plot of a Final Fantasy game – retrieve the scattered pieces of the key and decrypt the data.
Sounds a bit like a waste of time, but here’s the catch. The pieces of the statue of Gaia or some shit scattered pieces of the key are placed in distributed hash tables (DHTs). When you encrypt your data with Vanish, you also tell Vanish for how long you want that data to exist. The DHTs refresh their cubby holes every eight hours, and are told how many of these eight-hour slots to keep that data in there. Once the refreshes are up, the slot for data is open to be assigned to something else and the key piece disappears.
In simple terms, this allows you to send an email that will self-destruct in eight hours. Or 16 hours. Or whatever. After that time, the data is gone, irretrievable even to the sender and recipient. Of course, the recipient could have made a copy, but if he didn’t, there’s no amount of court orders that can bring that shit back.
Poor Vanessa Hudgens. If only she’d known.