In a recent posting, I explained how a vast space of cryptographic keys can be represented by a small piece of data. That’s due to the sheer power of exponential growth. To see a vast space of keys arising from sheer ingenuity, it’s worth a visit to the Musée Cluny in Paris, which houses a [...]

The tale is told that centuries ago, Grand Vizier Sissa Ben Dahir invented a new pleasure for his king, Shirham of India, the game of chess. Delighted, the king asked this vizier to name his reward. Sissa Ben Dahir was not just inventive, but mischievous. He archly requested a trifle, a mere portion of wheat: [...]

Alice has two secret documents, X and Y. She agrees to let Bob choose and receive one—but only one. Bob, however, doesn’t want Alice to know which document he has selected.  So they engage in a exchange of the utmost delicacy…

Cryptography has had a long affiliation with magic and the occult, as in Tetraktys. But there’s a more natural affinity between magic and what’s called steganography. Cryptography is the science of hiding the meaning of a message; steganography is the science of hiding the existence of a message within a document.
Steganography’s operating principle is diversion [...]

People often imagine that espionage and Internet security involve rapid, endless cycles of code-craft. Security experts cook up secret codes. Clever adversaries soon break them. New codes are then needed.

Tetraktys debuted at the RSA Conference this past week in a pre-release event.  It unfolded as a long festivity in which I was lucky to have my wife, my publishers from Emerald Bay Books, and numerous friends and colleagues at the conference join me.  The book was on sale at the conference bookstore, and Good [...]