Frank Rowlett.

Frank Byron Rowlett (May 2, 1908 - June 29, 1998) was an American cryptologist. Frank Rowlett NSA Photograph. ... Frank Rowlett NSA Photograph. ... May 2 is the 122nd day of the year in the Gregorian calendar (123rd in leap years). ... 1908 (MCMVIII) is a leap year starting on Wednesday (link will take you to calendar). ... June 29 is the 180th day of the year (181st in leap years) in the Gregorian Calendar, with 185 days remaining. ... 1998 (MCMXCVIII) is a common year starting on Thursday of the Gregorian calendar, and was designated the International Year of the Ocean. ... Pre-19th century Leone Battista Alberti, polymath/universal genius, inventor of polyalphabetic substitution (see frequency analysis for the significance of this -- missed by most for a long time and dumbed down in the Vigenère cipher), and what may have been the first mechanical encryption aid. ...

He was born in Rose Hill, Virginia and attended Emory & Henry College in Emory, Virginia, where he was a member of the Beta Lambda Zeta fraternity. In 1929 he received a bachelor's degree in mathematics and chemistry. He was hired by William Friedman as a "junior cryptanalyst" for the Signals Intelligence Service (SIS) on April Fool’s Day, 1930; shortly after, he was followed into SIS by Abraham Sinkov and Solomon Kullback. Rose Hill is the name of some places in the U.S. state of Virginia: Rose Hill, Fairfax County, Virginia Rose Hill, Lee County, Virginia This is a disambiguation page — a navigational aid which lists other pages that might otherwise share the same title. ... This article lacks information on the importance of the subject matter. ... -1... William Frederick Friedman (September 24, 1891 - November 12, 1969) served as a US Army cryptologist, running the research division of the Armys Signals Intelligence Service (SIS) through the 1930s and its follow-on services right into the 1950s. ... The Signals Intelligence Service (SIS) was the Armys codebreaking division. ... April Fools Day or All Fools Day, though not a holiday in its own right, is a notable day celebrated in many countries on April 1. ... Dr. Abraham Sinkov (1907-1998) was a US cryptanalyst. ... Solomon Kullback Dr Solomon Kullback (1903–1994) was a US cryptanalyst and mathematician. ...

During the 1930s, after a lengthy period of training, Rowlett and his colleagues compiled codes and ciphers for use by the U.S. Army and began solving a number of foreign, notably Japanese, systems. In the mid-1930s they solved the first Japanese machine for encipherment of diplomatic communications, known to the Americans as RED. In 1939-40, Rowlett led the SIS effort that solved a more sophisticated Japanese diplomatic machine cipher, codenamed PURPLE by the U.S. Once, when asked what his greatest contribution to that effort had been, Rowlett said, "I was the one who believed it could be done." In the context of cryptography, a code is a method used to transform a message into an obscured form, preventing those not in on the secret from understanding what is actually transmitted. ... This article is about algorithms for encryption and decryption. ... The Army is the branch of the United States armed forces which has primary responsibility for land-based military operations. ... This article is about algorithms for encryption and decryption. ... The United Nations, with its headquarters in New York City, is the largest international diplomatic organization. ... Red is a color at the lowest frequencies of light discernible by the human eye. ... The Signals Intelligence Service (SIS) was the Armys codebreaking division. ... Chromaticity diagram. ...

Rowlett also played a crucial role in protecting American communications during World War II, making fundamental and innovative contributions to the design of the SIGABA cipher machine. Its security was an important factor in saving American lives in combat. (In 1964, Congress awarded Rowlett US$100,000 as partial compensation for his classified cryptologic inventions). Combatants Allied Powers Axis Powers Commanders {{{commander1}}} {{{commander2}}} Strength {{{strength1}}} {{{strength2}}} Casualties 17 million military deaths 7 million military deaths World War II, also known as the Second World War (sometimes WW2 or WWII), was a mid-20th century conflict that engulfed much of the globe and is accepted as... SIGABA In the history of cryptography, the ECM Mark II was a rotor machine used by the United States from World War II (WWII) until the 1950s. ... This article is about algorithms for encryption and decryption. ... For the Nintendo 64 emulator, see 1964 (Emulator). ...

In addition to having highly-developed cryptanalytic skills, Rowlett was a good manager, and he rose quickly within the organization. In 1943-1945 he was chief of the General Cryptanalytic Branch, and in 1945-1947 chief of the Intelligence Division. From 1949 to 1952, he was technical director in the Office of Operations of the Armed Forces Security Agency, predecessor to the National Security Agency (NSA). 1943 (MCMXLIII) is a common year starting on Friday. ... 1945 (MCMXLV) was a common year starting on Monday (link will take you to calendar). ... 1945 (MCMXLV) was a common year starting on Monday (link will take you to calendar). ... 1947 (MCMXLVII) was a common year starting on Wednesday (link will take you to calendar). ... 1949 (MCMXLIX) is a common year starting on Saturday. ... 1952 (MCMLII) was a [[leap year starting on Tueday] (link will take you to calendar). ... This article is about the US government agency. ... NSA seal The National Security Agency / Central Security Service (NSA/CSS) is believed to be the largest United States government intelligence agency. ...

Rowlett differed with General Ralph J. Canine, the first director of NSA, over personnel movements, including his own. Acting on his differences, he transferred to the Central Intelligence Agency (CIA) in 1952 and worked there till 1958. At that time he returned to NSA as a Special Assistant to the Director. In 1965 Rowlett became commandant of the National Cryptologic School. He retired from federal service in 1966. In 1965 he was awarded the National Security Medal by President Lyndon B. Johnson for his work on breaking the Japanese Purple cipher. Lieutenant General Ralph J. Canine (1895-1969) was the first director of the United States National Security Agency (NSA). ... To meet Wikipedias quality standards, this article or section may require cleanup. ... 1952 (MCMLII) was a [[leap year starting on Tueday] (link will take you to calendar). ... 1958 (MCMLVIII) was a common year starting on Wednesday of the Gregorian calendar. ... NSA can stand for: National Security Agency of the USA The British Librarys National Sound Archive This page concerning a three-letter acronym or abbreviation is a disambiguation page — a navigational aid which lists other pages that might otherwise share the same title. ... 1965 (MCMLXV) was a common year starting on Friday (link goes to calendar). ... 1966 (MCMLXVI) was a common year starting on Saturday (link goes to calendar) // Events January January 1 - In a coup, Colonel Jean-Bédel Bokassa ousts president David Dacko and takes over the Central African Republic. ... 1965 (MCMLXV) was a common year starting on Friday (link goes to calendar). ... National Security Medal The National Security Medal is a decoration of the United States of America which was first created in 1947 by order of the United States National Security Council. ... Lyndon Baines Johnson (August 27, 1908 – January 22, 1973), often referred to as LBJ, was the 36th President of the United States (1963–1969). ... Chromaticity diagram. ...

Rowlett has been inducted into the Military Intelligence Hall of Fame. The Military Intelligence Hall of Fame is a Hall of Fame established by the Military Intelligence Corps of the U.S. Army to honor soldiers and civilians who have made exceptional contributions to Military Intelligence. ...

Because of his importance in the protection of American communications, the Information Systems Security Organization has named its highest award the Frank Byron Rowlett Award. Background The National Security Agency established the Information Systems Security National Awards in 1989 to recognize outstanding organizational and individual excellence in the field of information systems security. ...

Frank Rowlett died June 29, 1998, at age 90.

References

• Frank B. Rowlett, The Story of Magic: Memoirs of an American Cryptologic Pioneer, with Foreword and Epilogue by David Kahn, Laguna Hills, CA, Aegean Press, 1999.
• James Gannon, Stealing Secrets, Telling Lies: How Spies and Codebreakers Helped Shape the Twentieth Century, Washington, D.C., Brassey's, 2001, especially chapter 6: Who Broke Purple? (pp. 94-106).