How long pyramids take to build
Some years later, I had the good fortune of visiting the huge headquarters of the cipher machine company Crypto AG CAG , in Steinhausen, Switzerland, and befriending a high-level cryptographer there. My friend gave me an internal history of the company written by its founder, Boris Hagelin. It mentioned a cipher machine, the HX Like the Enigma, the HX was an electromechanical cipher system known as a rotor machine.
It was the only electromechanical rotor machine ever built by CAG, and it was much more advanced and secure than even the famous Enigmas. In fact, it was arguably the most secure rotor machine ever built. I longed to get my hands on one, but I doubted I ever would. Fast forward to I'm in a dingy third subbasement at a French military communications base. Accompanied by two-star generals and communications officers, I enter a secured room filled with ancient military radios and cipher machines.
I am amazed to see a Crypto AG HX, unrecognized for decades and consigned to a dusty, dimly lit shelf. I carefully extract the kilogram pound machine. There's a hand crank on the right side, enabling the machine to operate away from mains power. As I cautiously turn it, while typing on the mechanical keyboard, the nine rotors advance, and embossed printing wheels feebly strike a paper tape. I decided on the spot to do everything in my power to find an HX that I could restore to working order.
If you've never heard of the HX until just now, don't feel bad. Most professional cryptographers have never heard of it. Yet it was so secure that its invention alarmed William Friedman, one of the greatest cryptanalysts ever and, in the early s, the first chief cryptologist of the U. After reading a Hagelin patent more on that later , Friedman realized that the HX, then under development, was, if anything, more secure than the NSA's own KL-7 , then considered unbreakable.
The reasons for Friedman's anxiety are easy enough to understand. The HX had about 10 possible key combinations; in modern terms, that's equivalent to a 2,bit binary key. For comparison, the Advanced Encryption Standard , which is used today to protect sensitive information in government, banking, and many other sectors, typically uses a or a bit key. In the center of the cast-aluminum base of the HX cipher machine is a precision Swiss-made direct-current gear motor. Also visible is the power supply [lower right] and the function switch [left], which is used to select the operating mode—for example, encryption or decryption.
Peter Adams. A total of 12 different rotors are available for the HX, of which nine are used at any one time. Current flows into one of 41 gold-plated contacts on the smaller-diameter side of the rotor, through a conductor inside the rotor, out through a gold-plated contact on the other side, and then into the next rotor. 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.
Live TV. This Day In History. History Vault. Recommended for you. Egyptian Pyramids. The middle pyramid was built for Khafre Greek: Chephren , the fourth of the eight kings of the 4th dynasty. Pyramids today stand as a reminder of the ancient Egyptian glorification of life after death, and in fact, the pyramids were built as monuments to house the tombs of the pharaohs.
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Ben Davis May 31, How long would it take to build the pyramids today? How long did the pyramids take to build? How did the Sphinx lose its nose? Was a mummy ever found in a pyramid? How deep do the pyramids go? Are there Chambers in the Sphinx? Do pyramids have power? Did the Egyptians have electricity?
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