One Unbreakable Coding System, Slightly Used

By Edward Cone  |  Posted Monday, August 09, 2010 18:08 PM

by Tim Moran

Have you ever listened to shortwave radio? I seem to recall that, when I was a kid, my grandparents had a basic shortwave radio that I used to fiddle around with. I have little doubt that Alice figured she might pick up some transmissions from outer space.

In any event, had I given it any thought -- which I haven't -- I would have thought that, given today's sophisticated electronics communications technologies, the shortwave radio would have gone the way of tube amplifiers and rotary phones.

So it was with some surprise and interest that I read this recent story on npr.com titled, Numbers Stations: Mystery Over The Airwaves.

"In the shadowy corners of the shortwave radio spectrum, you can often find mysterious mechanical voices counting off endless strings of numbers--in English, Czech, Russian and German. . .even Morse code," it says. "But who's listening?"

Who, indeed. More to the point, who's broadcasting?

Apparently these are what are called "numbers stations" that have been on the air for years and long thought to be the work of spooks and spies. In fact, according to the NPR story, "the Russian spies recently captured here in the U.S. may have been getting orders from Moscow via a shortwave numbers station." These stations are unlicensed, naturally, and no government will admit to using them, making it virtually impossible for determine where they are broadcasting from--and why.

Max Stout, a spy historian quoted in the story, further suggests that "no matter how advanced modern computer cryptography is, good old shortwave is often the best option for getting messages to spies in the field." Further, computer communications invariably leave traces, whereas all you need with these transmissions is a pencil and paper and have knowledge of what he explains is "an unbreakable encryption system called a one-time pad: encryption key is completely random and changes with every message."

Spying by the numbers over an almost century-old comms technology. Priceless.