The Impetus to Creativity in Technology

We describe the ensuing developments from two now well-known publications in the 20th century. They contained significant and seminal technological results, a paper by Claude Shannon in 1948 and a patent by Horst Feistel in 1971. Shannon’s paper announces the challenge at the start, writing ``the fundamental problem of communication is that of reproducing at one point either exactly or approximately a message selected *sent+ at another point.‛ Shannon’s Coding Theorem established the relationship between the probability of receiving the message in error and transmission rate measuring the process efficiency. Shannon proved the existence of codes achieving optimal performance, but it required forty-five years to exhibit an actual code achieving it. The optimal-efficient Shannon codes are responsible for a wide range of communication technology we enjoy today, from GPS, to the NASA rovers Spirit and Opportunity on Mars, and also to worldwide communication over the Internet. US Patent #3798539A filed by the IBM Corporation in1971 described Horst Feistel’s Block Cipher Cryptographic System, a new paradigm for encryption systems. It was a departure from the current cryptographic technology based on shift-register stream encryption for voice and the variety of the electro-mechanical cipher machines introduced nearly fifty years before. Horst’s vision was its application to secure the privacy of computer files. It was invented at a propitious moment in time and implemented by IBM in automated teller machines for the Lloyds Bank Cashpoint System. The emergence of E-Commerce in the next decades would far overshadow the value of encryption in banking business. Finally, it has drastically altered the SIGINT mission of the National Security Agency. While Horst Feistel did not directly participate to any of these commercial applications of cryptography, the traditional interpretation of the law of cause and effect certainly describes the effect of Feistel’s patent.