"Cracking Codes and Stealing Secrets"
By Doug Peterson
Breaking codes can make or break historical figures, said best-selling author Simon Singh in a special CSL presentation aimed at school kids.
Singh, author of The Code Book, took students on a historical tour of codemaking and codebreaking in his CSL Golden Anniversary talk. As a classic example of how codes can change history, he told the story of Mary Queen of Scots, a Catholic who was chased out of an increasingly Protestant Scotland in the 16th Century.
Mary fled to England looking for protection from her cousin Elizabeth, the queen of England. But instead of receiving protection, she received 19 years in prison. As Singh pointed out, Queen Elizabeth was a Protestant, and she feared that Mary would inspire Catholics to rebel. So Mary landed in jail.
While in prison, Mary eventually began to plot rebellion, and that's when secret messages began to flow in and out of the prison - along with beer.
Because England's water was undrinkable at that time, the English consumed generous amounts of beer. So Mary and her co-conspirator, Anthony Babington, communicated by smuggling coded messages in and out of the prison in beer barrels. Little did they know that the person helping them smuggle messages was a double agent working for Queen Elizabeth.
With the double agent's help and some clever codebreaking, Elizabeth proved that Mary and Babington were planning to assassinate her and take the throne. The result: Mary Queen of Scots lost her head.
According to Singh, history is rich with examples of people who have sought secrecy by hiding their messages (steganography) and by encrypting their messages (cryptography).
To hide messages, one general in ancient Greece used a particularly inventive strategy, Singh said. The general shaved the head of a servant, tattooed the message on the fellow's bald scalp, waited a week, and then sent the servant on his way. The secret message was concealed under a fresh growth of hair.
Meanwhile, in the arena of cryptography, the Arabs in the ninth century were the first to use "frequency analysis" to unscramble coded messages, Singh pointed out. By studying every word and letter of the Koran, Muslim scholars noticed that some letters were more common than others. This knowledge provided the key to cracking certain ciphers.
In English, for instance, "e" is the most common letter, typically showing up 13 percent of the time. Singh said that codebreakers look for such patterns, deducing that if a certain letter or symbol shows up more than any other, it probably stands for the letter "e."
In the face of such codebreaking techniques, ciphers became increasingly sophisticated throughout the centuries. And with some regularity, cryptographers would become convinced that they had finally concocted an unbreakable code.
This was the case with the German's famous Enigma machine, a cipher device that was considered virtually impossible to break during World War II.
However, with major efforts by the Poles and British mathematicians, the Allies did crack the Enigma cipher. And one of the key codebreakers was Alan Turing.
"Turing never stood on any battlefield or flew any plane, but he probably made a greater contribution to the war effort than anybody else in Britain," Singh said.
But Turing never received acclaim for his achievements in his lifetime because codebreakers do not boast. The reason: If an enemy finds out that you have broken their cipher, they will strengthen it.
In World War II, the Allies went to great lengths to prevent the Germans from discovering that the Enigma had been broken. For instance, when the British discovered the locations of five German tankers refueling submarines in the Atlantic, they sank only three. If the British had taken out all five tankers, the Germans might have become suspicious.
Whether you're talking about Mary Queen of Scots or the German Enigma, "the moral of the story is that you have to have a good code," Singh said. "If your code is broken, the result can alter history."
By Doug Peterson
Breaking codes can make or break historical figures, said best-selling author Simon Singh in a special CSL presentation aimed at school kids.
Singh, author of The Code Book, took students on a historical tour of codemaking and codebreaking in his CSL Golden Anniversary talk. As a classic example of how codes can change history, he told the story of Mary Queen of Scots, a Catholic who was chased out of an increasingly Protestant Scotland in the 16th Century.
Mary fled to England looking for protection from her cousin Elizabeth, the queen of England. But instead of receiving protection, she received 19 years in prison. As Singh pointed out, Queen Elizabeth was a Protestant, and she feared that Mary would inspire Catholics to rebel. So Mary landed in jail.
While in prison, Mary eventually began to plot rebellion, and that's when secret messages began to flow in and out of the prison - along with beer.
Because England's water was undrinkable at that time, the English consumed generous amounts of beer. So Mary and her co-conspirator, Anthony Babington, communicated by smuggling coded messages in and out of the prison in beer barrels. Little did they know that the person helping them smuggle messages was a double agent working for Queen Elizabeth.
With the double agent's help and some clever codebreaking, Elizabeth proved that Mary and Babington were planning to assassinate her and take the throne. The result: Mary Queen of Scots lost her head.
According to Singh, history is rich with examples of people who have sought secrecy by hiding their messages (steganography) and by encrypting their messages (cryptography).
To hide messages, one general in ancient Greece used a particularly inventive strategy, Singh said. The general shaved the head of a servant, tattooed the message on the fellow's bald scalp, waited a week, and then sent the servant on his way. The secret message was concealed under a fresh growth of hair.
Meanwhile, in the arena of cryptography, the Arabs in the ninth century were the first to use "frequency analysis" to unscramble coded messages, Singh pointed out. By studying every word and letter of the Koran, Muslim scholars noticed that some letters were more common than others. This knowledge provided the key to cracking certain ciphers.
In English, for instance, "e" is the most common letter, typically showing up 13 percent of the time. Singh said that codebreakers look for such patterns, deducing that if a certain letter or symbol shows up more than any other, it probably stands for the letter "e."
In the face of such codebreaking techniques, ciphers became increasingly sophisticated throughout the centuries. And with some regularity, cryptographers would become convinced that they had finally concocted an unbreakable code.
This was the case with the German's famous Enigma machine, a cipher device that was considered virtually impossible to break during World War II.
However, with major efforts by the Poles and British mathematicians, the Allies did crack the Enigma cipher. And one of the key codebreakers was Alan Turing.
"Turing never stood on any battlefield or flew any plane, but he probably made a greater contribution to the war effort than anybody else in Britain," Singh said.
But Turing never received acclaim for his achievements in his lifetime because codebreakers do not boast. The reason: If an enemy finds out that you have broken their cipher, they will strengthen it.
In World War II, the Allies went to great lengths to prevent the Germans from discovering that the Enigma had been broken. For instance, when the British discovered the locations of five German tankers refueling submarines in the Atlantic, they sank only three. If the British had taken out all five tankers, the Germans might have become suspicious.
Whether you're talking about Mary Queen of Scots or the German Enigma, "the moral of the story is that you have to have a good code," Singh said. "If your code is broken, the result can alter history."
Simon Singh
Best-selling author of The Code Book and Fermat's Enigma
BBC director of an award-winning documentary on Fermat's Last Theorem, which aired on PBS's "Nova" series.
Presentation Title: "Cracking Codes and Stealing Secrets"
Delivered:
April 6, 2001
Best-selling author of The Code Book and Fermat's Enigma
BBC director of an award-winning documentary on Fermat's Last Theorem, which aired on PBS's "Nova" series.
Presentation Title: "Cracking Codes and Stealing Secrets"
Delivered:
April 6, 2001
