The Code Book: The Science of Secrecy from Ancient Egypt to Quantum Cryptography

While al-Kindī was describing the invention of cryptanalysis, Europeans were still struggling with the basics of cryptography.

The spread of the Christian Church was responsible for the extinction of the Egyptian scripts, outlawing their use in order to eradicate any link with Egypt’s pagan past.

Marconi could soon transmit and receive pulses of information across distances of up to 2.5 km. He had invented radio.

Furthermore, quantum cryptography has an additional benefit: it provides a way for Alice and Bob to find out if Eve is eavesdropping. Eve’s presence on the line becomes apparent because every time that she measures a photon, she risks altering it, and these alterations become obvious to Alice and Bob.

Hence, in parallel with the development of steganography, there was the evolution of cryptography, derived from the Greek word kryptos, meaning “hidden.” The aim of cryptography is not to hide the existence of a message, but rather to hide its meaning, a process known as encryption

Before the overhaul of the postage system in the mid-1800s, sending a letter cost about a shilling for every hundred miles, beyond the means of most people. However, newspapers could be posted free of charge, and this provided a loophole for thrifty Victorians. Instead of writing and sending letters, people began to use pinpricks to spell out a mes

So the race is on. The really important question is whether quantum cryptography will arrive in time to save us from the threat of quantum computers, or whether there will be a privacy gap, a period between the development of quantum computers and the advent of quantum cryptography. So far, quantum cryptography is the more advanced technology.

One of the most intrepid plans for stealing keys was concocted by Ian Fleming, creator of James Bond and a member of Naval Intelligence during the war. He suggested crashing a captured German bomber in the English Channel, close to a German ship. The German sailors would then approach the plane to rescue their comrades, whereupon the aircrew, Briti

In fact the process can be swapped around, so that the private key is used for encrypting and the public key is used for decrypting. This mode of encryption is usually ignored because it offers no security. If Alice uses her private key to encrypt a message to Bob, then everybody can decrypt it because everybody has Alice’s public key. However, thi