cryptanalysis
Quick Summary
The German navy employed various versions of the Enigma cipher machine during the war, including this four-rotor model.
Cryptanalysis is the practice of deciphering or forging communications secured by cryptography. It involves solving cryptograms or cryptographic systems, and also includes the theory and methods for doing so. Historically, cryptanalysis was considered as much an art as a science, relying on intuition and pattern recognition. However, modern cryptanalysis heavily utilizes mathematics and significant computing power.123
There are three main types of cryptanalysis, categorized by what the cryptanalyst knows: ciphertext only, known ciphertext/plaintext pairs, and chosen plaintext or chosen ciphertext. Famous historical examples of cryptanalytic success include breaking Japanese codes during the Battle of Midway in World War II and deciphering the Zimmermann Telegram in World War I.1
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Battle of GuadalcanalThe land campaign on Guadalcanalcryptanalysts, who had penetrated the Japanese naval code. The Japanese, believing that the Americans had withdrawn many of their troops after the stinging defeat at Savo Island, vastly underestimated the strength of the U.S. presence on Guadalcanal. In the predawn hours of August 21, the…
Read Morecryptanalysts, who had penetrated the Japanese naval code. The Japanese, believing that the Americans had withdrawn many of their troops after the stinging defeat at Savo Island, vastly underestimated the strength of the U.S. presence on Guadalcanal. In the predawn hours of August 21, the…
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20th-century international relationsScience and technology in wartime…this more evident than in cryptanalysis and espionage, in which the Allies repeatedly bested the otherwise secretive and devious Axis. As early as 1931, Captain Gustave Bertrand of French intelligence procured documents from a German traitor concerning the cryptographic rotor device Enigma. The brilliant Polish mathematician Marian Rejewski cracked
Read More…this more evident than in cryptanalysis and espionage, in which the Allies repeatedly bested the otherwise secretive and devious Axis. As early as 1931, Captain Gustave Bertrand of French intelligence procured documents from a German traitor concerning the cryptographic rotor device Enigma. The brilliant Polish mathematician Marian Rejewski cracked
Read More