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The Untold Story of the Man That Made Mainstream Encryption Possible
Meet Whit Diffie, the man who invented public key cryptography and brought encryption to the masses

Longtime tech journalist Steven Levy’s new book, Facebook: The Inside Story, details how Mark Zuckerberg transformed a tasteless dorm room social networking experiment into the world’s biggest social networking business. In honor of that release, we thought we’d share an excerpt of an earlier Levy book, Crypto, about a man who ran in the opposite direction of Facebook’s data exploitation and privacy breaches. This is the story of Whit Diffie, who transformed how we think of encryption, paving the way for the digital security we enjoy today.
Bailey Whitfield Diffie, born June 5, 1944, was always an independent sort. As one early friend remarked, “The kid had an alternative lifestyle at age five.” Diffie didn’t read until he was 10 years old. There was no question of disability, he simply preferred that his parents read to him, which seemingly they did, quite patiently. Finally, in the fifth grade, Diffie spontaneously worked his way through a tome called The Space Cat, and immediately progressed to the Oz books.
Later that year his teacher at P.S. 178 — “Her name was Mary Collins and if she is still alive I’d like to find her,” Diffie would say decades later — spent an afternoon explaining something that would stick with him for a very long time: the basics of cryptography.
Diffie found cryptography a delightfully conspiratorial means of expression. Its users collaborate to keep secrets in a world of prying eyes. A sender attempts this by transforming a private message to an altered state, a sort of mystery language: encryption. Once the message is transformed into a cacophonous babble, potential eavesdroppers are foiled. Only those in possession of the rules of transformation can restore the disorder back to the harmony of the message as it was first inscribed: decryption. Those who don’t have that knowledge and try to decrypt messages without the secret “keys” are practicing “cryptanalysis.”
Although Diffie performed competently in school, he never did apply himself. Only stratospheric scores on standardized tests enabled him to enter the…