Are typewriters the answer to snooping?

IBM typewriter Image copyright AP

Last week the Magazine reported on Gordon Martin, the 86-year-old correspondent who prefers a typewriter to a computer. The story pointed out that some diplomats now use typewriters to evade electronic eavesdropping - but are these totally secure? Negative, says BBC security correspondent Gordon Corera.

The Snowden revelations about US electronic eavesdropping led to a rash of stories about countries turning away from electronic communications. Russia and India were reported to have ordered typewriters - the theory being that this would shelter them from the prying eyes and ears of Western intelligence agencies. But is paper really safer?

In some ways it is. Chelsea Manning (formerly Bradley Manning) and Edward Snowden have shown how easy it is to take away electronic documents in bulk. To steal the paper equivalent of the wikileaks cache would have taken fork-lift trucks to move - and someone might have noticed that. Instead, a USB stick, a CD or maybe a hard-drive is now all you need.

But paper and typewriters still have vulnerabilities - and the Russians should know this. For instance, it's possible to reconstruct from a typewriter ribbon some of what was written using it. This was done with a ribbon found by the FBI amid the rubbish of CIA officer Aldrich Ames, who had become a double agent for the KGB, and the resulting text revealed plans for a meeting in Venezuela.

There are even more ingenious ways to spy on a typewriter. In 1985, CBS News reported that Soviet agents had installed sensors in a dozen typewriters in the US Embassy in Moscow. "The devices picked up the contents of documents typed by embassy secretaries and transmitted them by antennas hidden in the embassy walls," CBS said. The typewriters used a round ball with numbers and letters around the surface, which revolved before hitting the ribbon against the paper. The bugs could work out each letter typed by detecting how the ball moved.

A National Security Agency study of the episode, largely declassified, notes with grudging admiration that the bugs - 16 in total - had been put in place by customs officers when the typewriters were shipped into the country. They had gone undetected for about eight years.

The lesson - as many a security professional will tell you - is that if a well-resourced opponent really wants to find out what you are writing, then they will find a way. It may not be cheap or easy, it may involve using a mix of technology and human agents, but if they think it is worth it, you will find it very very hard to stop them.

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