|
|
Codebreakers
|
|
|
|
Program Overview
|
|
|
During World War II, as in other wars, important messages were often
sent by radio in code. Frequently, these messages were sent as
ciphers, in which each letter of a word was represented by another
letter, a number, or a combination of letters and numbers. These
hand-encoded messages provided some security, but there was always
the threat that an enemy agent would pick up radio signals, crack
the code, and interpret the message. The more a code was used, the
greater the chances were that it would be broken; yet it was
impractical to change codes frequently. There was also the risk that
codebooks would be captured and used by another nation.
A significant development in secret communications came with the
invention of machines that could create ciphers. This program
highlights two World War II machines, the German "Enigma Machine"
and the Japanese "Purple Cipher Machine," which could create
millions of ciphers without the use of codebooks. Each message
carried a key that was used to calibrate the recipient's machine to
the sender's machine. These machines created a great challenge for
codebreakers trying to eavesdrop on foreign communications.
|
|
