His ideas took shape in when he sent a wireless Morse Code message to a source more than a kilometer away. He continued to work on his new invention, and in he received the official British patent for the radio — which was really a wireless telegraph system at first. Other inventors in Russia and the United States had been working on similar devices, but Marconi made the right political and business connections to gain the first real success with the device.
By there were four competing wireless systems. In the years just before World War I, scientists at companies such as American Telephone and Telegraph, General Electric, and Westinghouse and inventors — including Reginald Fessenden, Lee De Forest and Cyril Elwell — were mapping out ways they could develop the potential of wireless communication so it could broadcast more sophisticated messages than the dots and dashes of Morse Code.
Radio was developed for its military applications in the pre-World War I years, and the U. Navy held the patents. In , Marconi shared the Nobel Prize for physics with Ferdinand Braun, a German, in recognition of their contributions to the development of wireless telegraphy. Radio works by changing sounds or signals into radio waves, which travel through air, space, and solid objects, and the radio receiver changes them back into the sounds, words, and music we hear.
A radio broadcast is a one-way transmission, originating from a radio station. By the s, most households in the U. The incrementing of each rotor is programmed by setting pins, which are just visible in the horizontal rotor. Just as worrisome was that CAG was a privately owned Swiss company, selling to any government, business, or individual. But traffic encrypted by the HX would be unbreakable.
Friedman and Hagelin were good friends. During World War II, Friedman had helped make Hagelin a very wealthy man by suggesting changes to one of Hagelin's cipher machines, which paved the way for the U. Army to license Hagelin's patents. The resulting machine, the MB , became a workhorse during the war, with some , units fielded.
Hagelin agreed not to sell his most secure machines to countries specified by U. He convinced Hagelin not to manufacture the new device, even though the machine had taken more than a decade to design and only about 15 had been built, most of them for the French army. However, was an interesting year in cryptography. Machine encryption was approaching a crossroads; it was starting to become clear that the future belonged to electronic encipherment. Even a great rotor machine like the HX would soon be obsolete.
That was a challenge for CAG, which had never built an electronic cipher machine. Introduced in , the machine was a failure. Also in , Hagelin's son Bo, who was the company's sales manager for the Americas and who had opposed the transaction, died in a car crash near Washington, D.
Although the H was a failure, it was succeeded by a machine called the H, of which thousands were sold. The H was designed with NSA assistance. To generate random numbers, it used multiple shift registers based on the then-emerging technology of CMOS electronics. This mathematical algorithm was created by the NSA, which could therefore decrypt any messages enciphered by the machine.
From then on, its electronic machines, such as the HC series, were secretly designed by the NSA, sometimes with the help of corporate partners such as Motorola. This U. The backdooring of all CAG machines continued until , when the company was liquidated. William F. Friedman [top] dominated U. National Security Agency. His friend Boris Hagelin [bottom], a brilliant Swedish inventor and entrepreneur, founded Crypto AG in in Zug, Switzerland, and built it into the world's largest cipher-machine company.
TOP, U. Parts of this story emerged in leaks by CAG employees before and, especially, in a subsequent investigation by the Washington Post and a pair of European broadcasters, Zweites Deutsches Fernsehen , in Germany, and Schweizer Radio und Fernsehen , in Switzerland. The Post 's article , published on 11 February , touched off firestorms in the fields of cryptology, information security, and intelligence.
The revelations badly damaged the Swiss reputation for discretion and dependability. They triggered civil and criminal litigation and an investigation by the Swiss government and, just this past May, led to the resignation of the Swiss intelligence chief Jean-Philippe Gaudin, who had fallen out with the defense minister over how the revelations had been handled.
In fact, there's an interesting parallel to our modern era, in which backdoors are increasingly common and the FBI and other U. Even before these revelations, I was deeply fascinated by the HX, the last of the great rotor machines.
This particular unit, different from the one I had seen a decade before, had been untouched since I immediately began to plan the restoration of this historically resonant machine. People have been using codes and ciphers to protect sensitive information for a couple of thousand years. The first ciphers were based on hand calculations and tables. In , a mechanical device that became known as the Alberti cipher wheel was introduced.
Then, just after World War I, an enormous breakthrough occurred, one of the greatest in cryptographic history : Edward Hebern in the United States, Hugo Koch in the Netherlands, and Arthur Scherbius in Germany, within months of one another, patented electromechanical machines that used rotors to encipher messages. Thus began the era of the rotor machine. Scherbius's machine became the basis for the famous Enigma used by the German military from the s until the end of WW II.
To understand how a rotor machine works, first recall the basic goal of cryptography: substituting each of the letters in a message, called plaintext, with other letters in order to produce an unreadable message, called ciphertext.
It's not enough to make the same substitution every time—replacing every F with a Q , for example, and every K with an H. Such a monoalphabetic cipher would be easily solved. A simple cipher machine, such as the Enigma machine used by the German Army during World War II, has three rotors, each with 26 positions.
Each position corresponds to a letter of the alphabet. Electric current enters at a position on one side of the first rotor, corresponding to a letter, say T. The current travels through two other rotors in the same way and then, finally, exits the third rotor at a position that corresponds to a different letter, say R. So in this case, the letter T has been encrypted as R.
The next time the operator strikes a key, one or more of the rotors move with respect to one another, so the next letter is encrypted with an entirely different set of permutations.
In the Enigma cipher machines [below] a plugboard added a fixed scramble to the encipherment of the rotors, swapping up to 13 letter pairs. A rotor machine gets around that problem using—you guessed it—rotors. Start with a round disk that's roughly the diameter of a hockey puck, but thinner.
On both sides of the disk, spaced evenly around the edge, are 26 metal contacts, each corresponding to a letter of the English alphabet. Inside the disk are wires connecting a contact on one side of the disk to a different one on the other side. The disk is connected electrically to a typewriter-like keyboard. When a user hits a key on the keyboard, say W , electric current flows to the W position on one side of the rotor.
The current goes through a wire in the rotor and comes out at another position, say L. However, after that keystroke, the rotor rotates one or more positions. So the next time the user hits the W key, the letter will be encrypted not as L but rather as some other letter.
Though more challenging than simple substitution, such a basic, one-rotor machine would be child's play for a trained cryptanalyst to solve. So rotor machines used multiple rotors. Versions of the Enigma, for example, had either three rotors or four. The use of wireless signaling increased after it was proved to be effective in communication for rescue work at sea. Soon a number of ocean liners even installed wireless equipment.
Two years later, the Navy adopted a wireless system. Up until then, the Navy had been using visual signaling and homing pigeons for communication. In , radiotelegraph service was established between five Hawaiian Islands.
In , the naval battle of Port Arthur in the Russo-Japanese war was reported by wireless. And in , the U. Weather Bureau experimented with radiotelegraphy to speed up notice of weather conditions. Robert E. Peary, an arctic explorer, radiotelegraphed "I found the Pole" in A year later, Marconi established regular American-European radiotelegraph service, which several months later enabled an escaped British murderer to be apprehended on the high seas. In , the first transpacific radiotelegraph service was established, linking San Francisco with Hawaii.
Meanwhile, overseas radiotelegraph service developed slowly, primarily because the initial radiotelegraph transmitter was unstable and caused a high amount of interference.
The Alexanderson high-frequency alternator and the De Forest tube eventually resolved many of these early technical problems. Lee de Forest was the inventor of space telegraphy, the triode amplifier, and the Audion, an amplifying vacuum tube. In the early s, the development of radio was hampered by the lack of an efficient detector of electromagnetic radiation.
It was De Forest who provided that detector. His invention made it possible to amplify the radio frequency signal picked up by antennae. This allowed for the use of much weaker signals than had previously been possible. De Forest was also the first person to use the word "radio.
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