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JN-25
The vulnerability of Japanese naval codes and ciphers was crucial to the conduct of World War II, and had an important influence on foreign relations between Japan and the west in the years leading up to the war as well. Every Japanese code was eventually broken, and the intelligence gathered made possible such operations as the victorious American ambush of the Japanese Navy at Battle of Midway, Midway in 1942 (by breaking code JN-25b) and the shooting down of Japanese admiral Isoroku Yamamoto a year later in Operation Vengeance. The Imperial Japanese Navy (IJN) used many codes and ciphers. All of these cryptosystems were known differently by different organizations; the names listed below are those given by Western cryptanalytic operations. Red code The Red Book code was an IJN code book system used in World War I and after. It was called "Red Book" because the American photographs made of it were bound in red covers.Greg Goebel"US Codebreakers In The Shadow Of War" 2018. It sh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Station HYPO
Station HYPO, also known as Fleet Radio Unit Pacific (FRUPAC), was the United States Navy signals monitoring and cryptographic intelligence unit in Hawaii during World War II. It was one of two major Allied signals intelligence units, called Fleet Radio Units in the Pacific theaters, along with FRUMEL in Melbourne, Australia. The station took its initial name from the phonetic code at the time for "H" for Heʻeia, Hawaii radio tower. The precise importance and role of HYPO in penetrating the Japanese naval codes has been the subject of considerable controversy, reflecting internal tensions amongst US Navy cryptographic stations. HYPO was under the control of the OP-20-G Naval Intelligence section in Washington. Before the attack on Pearl Harbor of December 7, 1941, and for some time afterwards, HYPO was in the basement of the Old Administration Building at Pearl Harbor. Later on, a new building was constructed for the station, though it had been reorganized and renamed by t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Station CAST
Station CAST was the United States Navy signals monitoring and cryptographic intelligence fleet radio unit at Cavite Navy Yard in the Philippines, until Cavite was captured by the Japanese forces in 1942, during World War II. It was an important part of the Allied intelligence effort, addressing Japanese communications as the War expanded from China into the rest of the Pacific theaters. As Japanese advances in the Philippines threatened CAST, its staff and services were progressively transferred to Corregidor in Manila Bay, and eventually to a newly formed US-Australian station, FRUMEL in Melbourne, Australia. STATION CAST had originally been located at Shanghai but had been evacuated to Cavite in early 1941 as part of the US Navy's disengagement with China. Prior to the war, CAST was the US Navy's Far East cryptographic operation, under the OP-20-G Naval Intelligence section in Washington. It was located at the Navy Yard in Manila and moved into the tunnels on Corregidor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Far East Combined Bureau
The Far East Combined Bureau, an outstation of the British Government Code and Cypher School, was set up in Hong Kong in March 1935, to monitor Japanese, and also Chinese and Russian (Soviet) intelligence and radio traffic. Later it moved to Singapore, Colombo (Ceylon), Kilindini (Kenya), then returned to Colombo. The Colombo site was known as HMS Anderson or Station Anderson. Hong Kong The FECB was located in an office block in the Naval dockyard, with an armed guard at the door (which negated any attempt at secrecy). The intercept site was on Stonecutters Island, four miles across the harbour, and manned by a dozen RAF and RN ratings (plus later four Army signallers). The codebreaking or Y section had Japanese, Chinese and Russian interpreters, under RN Paymaster Henry (Harry) Shaw, with Dick Thatcher and Neil Barnham. The FECB was headed by the Chief of Intelligence Staff (COIS) Captain John Waller, later by Captain F. J. Wylie. Shaw had been dealing direct with GC&CS an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Joseph Rochefort
Joseph John Rochefort (May 12, 1900 – July 20, 1976) was an American naval officer and cryptanalyst. He was a major figure in the United States Navy's cryptographic and intelligence operations from 1925 to 1946, particularly in the Battle of Midway. His contributions and those of his team were pivotal to victory in the Pacific War. Early career Rochefort was born May, 12, 1900, in Dayton, Ohio. In 1917, he joined the United States Navy while still in high school in Los Angeles, without obtaining a diploma. When enlisting he gave his birth date as 1898; this adjustment lasted his entire career. He was commissioned as an Ensign after a 14 June 1919 graduation from the US Navy's Steam Engineering School at Stevens Institute of Technology, and later in 1919, became engineering officer of the tanker USS ''Cuyama''. A fellow officer observed that Rochefort had a penchant for solving crossword puzzles and adept skills at playing the advanced card game auction bridge and recommended ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Agnes Driscoll
Agnes Meyer Driscoll (July 24, 1889 – September 16, 1971), known as "Miss Aggie" or "Madame X'", was an American cryptanalyst during both World War I and World War II and was known as "the first lady of naval cryptology." Early years Driscoll was born Agnes May Meyer in Geneseo, Illinois, in 1889. She moved with her family to Westerville, Ohio, in 1895, where her father, Gustav Meyer, had taken a job teaching music at Otterbein College. In 1909, he donated the family home to the Anti-Saloon League, which had recently moved its headquarters to Westerville. The home was later donated to the Westerville Public Library and is now home to the Anti-Saloon League Museum and the Westerville Local History Center. Education Driscoll attended Otterbein College from 1907 to 1909. In 1911, she received a Bachelor of Arts degree from Ohio State University, having majored in mathematics and physics and studied foreign languages, statistics and music. She was fluent in English, French, Germ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Operation Vengeance
Operation Vengeance was the American military operation to kill Admiral Isoroku Yamamoto of the Imperial Japanese Navy on 18 April 1943 during the Solomon Islands campaign in the Pacific Theater of World War II. Yamamoto, commander of the Combined Fleet of the Imperial Japanese Navy, was killed near Bougainville Island when his G4M1 transport aircraft was shot down by United States Army Air Forces fighter aircraft operating from Kukum Field on Guadalcanal. The mission of the U.S. aircraft was specifically to kill Yamamoto, made possible because of United States Navy intelligence decoding transmissions about Yamamoto's travel itinerary through the Solomon Islands area. The death of Yamamoto reportedly damaged the morale of Japanese naval personnel, raised the morale of the Allied forces, and was intended as revenge by U.S. leaders, who blamed Yamamoto for the attack on Pearl Harbor that initiated the war between Imperial Japan and the United States. The U.S. pilots claimed to ha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Battle Of Midway
The Battle of Midway was a major naval battle in the Pacific Ocean theater of World War II, Pacific Theater of World War II that took place on 4–7 June 1942, six months after Japan's attack on Pearl Harbor and one month after the Battle of the Coral Sea. The Japanese Combined Fleet under the command of Isoroku Yamamoto suffered a decisive defeat by the United States Pacific Fleet, U.S. Pacific Fleet near Midway Atoll, about northwest of Oahu. Yamamoto had intended to capture Midway and lure out and destroy the U.S. Pacific Fleet, especially the aircraft carriers which had escaped damage at Pearl Harbor. Before the battle, Japan desired to extend its Pacific defense perimeter, especially after the Doolittle Raid, Doolittle air raid of Tokyo in April 1942, and to clear the seas for attacks on Midway, Fiji, Samoa, and Hawaii. A related Japanese Aleutian Islands campaign, attack on the Aleutian Islands began one day earlier, on 3 June. The Japanese strike force at Midway, known ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isoroku Yamamoto
was a Marshal Admiral of the Imperial Japanese Navy (IJN) and the commander-in-chief of the Combined Fleet during World War II. He commanded the fleet from 1939 until his death in 1943, overseeing the start of the Pacific War in 1941 and Japan's initial successes and defeats before his plane was shot down by U.S. fighter aircraft over New Guinea. Yamamoto graduated from the Imperial Naval Academy in 1904 and served in the Russo-Japanese War, where he lost two fingers at the Battle of Tsushima. He later studied at Harvard University in the United States and was appointed naval attaché to the Japanese embassy in Washington. His experiences convinced him that naval power depended on access to oil and industrial capacity, and that Japan thus had little hope to defeat the U.S. in a war. He was one of the first naval leaders to conclude that naval aviation and aircraft carriers would play a decisive role in any future conflict. In 1936, Yamamoto was appointed navy vice minist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Code Book
A codebook is a type of document used for gathering and storing cryptography codes. Originally, codebooks were often literally , but today "codebook" is a byword for the complete record of a series of codes, regardless of physical format. Cryptography In cryptography, a codebook is a document used for implementing a code. A codebook contains a lookup table for coding and decoding; each word or phrase has one or more strings which replace it. To decipher messages written in code, corresponding copies of the codebook must be available at either end. The distribution and physical security of codebooks presents a special difficulty in the use of codes compared to the secret information used in ciphers, the key, which is typically much shorter. The United States National Security Agency documents sometimes use ''codebook'' to refer to block ciphers; compare their use of ''combiner-type algorithm'' to refer to stream ciphers. Codebooks come in two forms, one-part or two-part: * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Attack On Pearl Harbor
The attack on Pearl HarborAlso known as the Battle of Pearl Harbor was a surprise military strike by the Empire of Japan on the United States Pacific Fleet at Naval Station Pearl Harbor, its naval base at Pearl Harbor on Oahu, Territory of Hawaii, Hawaii, on December 7, 1941. At the time, the U.S. was a Neutral powers during World War II, neutral country in World War II. The air raid on Pearl Harbor, which was launched from Aircraft carrier, aircraft carriers, resulted in the U.S. entering the war on the side of the Allies of World War II, Allies on the day following the attack. The Imperial General Headquarters, Japanese military leadership referred to the attack as the Hawaii Operation and Operation AI, and as Operation Z during its planning. The attack on Pearl Harbor was preceded by months of negotiations between the U.S. and Japan over the future of the Pacific Ocean, Pacific. Japanese demands included that the U.S. ABCD line, end its sanctions against Japan, cease aidi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Punched Card
A punched card (also punch card or punched-card) is a stiff paper-based medium used to store digital information via the presence or absence of holes in predefined positions. Developed over the 18th to 20th centuries, punched cards were widely used for data processing, the control of automated machines, and computing. Early applications included controlling weaving looms and recording census data. Punched cards were widely used in the 20th century, where unit record equipment, unit record machines, organized into data processing systems, used punched cards for Input (computer science), data input, data output, and data storage. The IBM 12-row/80-column punched card format came to dominate the industry. Many early digital computers used punched cards as the primary medium for input of both computer programs and Data (computing), data. Punched cards were used for decades before being replaced by magnetic storage and terminals. Their influence persists in cultural references, sta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
World War II
World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the world's countries participated, with many nations mobilising all resources in pursuit of total war. Tanks in World War II, Tanks and Air warfare of World War II, aircraft played major roles, enabling the strategic bombing of cities and delivery of the Atomic bombings of Hiroshima and Nagasaki, first and only nuclear weapons ever used in war. World War II is the List of wars by death toll, deadliest conflict in history, causing World War II casualties, the death of 70 to 85 million people, more than half of whom were civilians. Millions died in genocides, including the Holocaust, and by massacres, starvation, and disease. After the Allied victory, Allied-occupied Germany, Germany, Allied-occupied Austria, Austria, Occupation of Japan, Japan, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
