Despite publicity given to the successes of British and American codebreakers during the Second World War, the study of signals intelligence is still complicated by governmental secrecy over even the most elderly peacetime sigint. This book, first published in 1986, lifts the veil on some of these historical secrets. Christopher Andrew and Keith Neilson cast new light on how Tsarist codebreakers penetrated British code and cypher systems. John Chapman’s study of German military codebreaking represents a major advance in our understanding of cryptanalysis during the Weimar Republic. The history of the Government Code and Cypher School – forerunner of today’s GCHQ – by its operational head, the late A.G. Denniston, provides both a general assessment of the achievements of British cryptanalysis between the wars and a tantalising glimpse of what historians may one day find in GCHQ’s forbidden archives. The distinguished cryptanalyst of Bletchley Park, the late Gordon Welchman, describes in detail how the Ultra programme defeated the German Enigma machine, while another Bletchley Park cryptographer, Christopher Morris, reminds us in his account of the valuable work on hand cyphers that wartime sigint consisted of much more than Ultra. Roger Austin’s study of surveillance under the Vichy regime shows the continuing importance of older and simpler methods of message interception such as letter-opening. Taken together, the articles establish sigint as an essential field of study for both the modern historian and the political scientist.

The untold story of Bletchley Park's key role in the success of the Normandy campaign Since the secret of Bletchley Park was revealed in the 1970s, the work of its codebreakers has become one of the most famous stories of the Second World War. But cracking the Nazis' codes was only the start of the process. Thousands of secret intelligence workers were then involved in making crucial information available to the Allied leaders and commanders who desperately needed it. Using previously classified documents, David Kenyon casts the work of Bletchley Park in a new light, as not just a codebreaking establishment, but as a fully developed intelligence agency. He shows how preparations for the war's turning point--the Normandy Landings in 1944--had started at Bletchley years earlier, in 1942, with the careful collation of information extracted from enemy signals traffic. This account reveals the true character of Bletchley's vital contribution to success in Normandy, and ultimately, Allied victory.

In Code Warriors, Stephen Budiansky--a longtime expert in cryptology--tells the fascinating story of how NSA came to be, from its roots in World War II through the fall of the Berlin Wall. Along the way, he guides us through the fascinating challenges faced by cryptanalysts, and how they broke some of the most complicated codes of the twentieth century. With access to new documents, Budiansky shows where the agency succeeded and failed during the Cold War, but his account also offers crucial perspective for assessing NSA today in the wake of the Edward Snowden revelations. Budiansky shows how NSA's obsession with recording every bit of data and decoding every signal is far from a new development; throughout its history the depth and breadth of the agency's reach has resulted in both remarkable successes and destructive failures.

Central Bureau - Australia's own large and sophisticated intelligence network, built from scratch. It was this group of mathematicians, code-breakers, and radio experts who intercepted the travel plans of the architect of the Pearl Harbor attack, Admiral Yamamoto, leading to his ambush and death. Australian signals intelligence also played a vital role in the battles of the Coral Sea, Milne Bay, Hollandia, and many others. General Douglas MacArthur, the supreme commander of the local Allied forces, went so far as to insist that the men of Central Bureau accompany him on his counter-attack in the Pacific. After the war, the US sought to give these non-combatants the highest awards possible - honours that were suppressed by the Australian government in their need for secrecy. A groundbreaking work of military history, The Secret Code-breakers of Central Bureau gives these talented and dedicated individuals their due at last. It is a rich account of the shadowy side of military strength and of the men and women whose work was, in the words of the US navy, of 'immeasurable importance in the successfulmprosecution' of the Pacific War. 'Who knew? This enthralling study tells a deeply human story. The men and women who gave our troops a significant edge in the fight against the Japanese are the genuine heroes in this engaging and exciting book.' -Michael McKernan, author of The Strength of a Nation and When This Thing Happened 'This is history and military strategy written at its most engaging.' -Waikato Times 'A delightfully and thoroughly engaging story of the emergence of the Australian contribution to the signals and radio interception intelligence ... Dufty's writing style is light and easy to read, reminiscent of other contemporary historical narratives that tell a series of stories, most notably the emphasis of the human story associated with these experiences.' -Rhys Ball, NZ International Review

Despite publicity given to the successes of British and American codebreakers during the Second World War, the study of signals intelligence is still complicated by governmental secrecy over even the most elderly peacetime sigint. This book, first published in 1986, lifts the veil on some of these historical secrets. Christopher Andrew and Keith Neilson cast new light on how Tsarist codebreakers penetrated British code and cypher systems. John Chapman’s study of German military codebreaking represents a major advance in our understanding of cryptanalysis during the Weimar Republic. The history of the Government Code and Cypher School – forerunner of today’s GCHQ – by its operational head, the late A.G. Denniston, provides both a general assessment of the achievements of British cryptanalysis between the wars and a tantalising glimpse of what historians may one day find in GCHQ’s forbidden archives. The distinguished cryptanalyst of Bletchley Park, the late Gordon Welchman, describes in detail how the Ultra programme defeated the German Enigma machine, while another Bletchley Park cryptographer, Christopher Morris, reminds us in his account of the valuable work on hand cyphers that wartime sigint consisted of much more than Ultra. Roger Austin’s study of surveillance under the Vichy regime shows the continuing importance of older and simpler methods of message interception such as letter-opening. Taken together, the articles establish sigint as an essential field of study for both the modern historian and the political scientist.

The award-winning New York Times bestseller about the American women who secretly served as codebreakers during World War II--a "prodigiously researched and engrossing" (New York Times) book that "shines a light on a hidden chapter of American history" (Denver Post). Recruited by the U.S. Army and Navy from small towns and elite colleges, more than ten thousand women served as codebreakers during World War II. While their brothers and boyfriends took up arms, these women moved to Washington and learned the meticulous work of code-breaking. Their efforts shortened the war, saved countless lives, and gave them access to careers previously denied to them. A strict vow of secrecy nearly erased their efforts from history; now, through dazzling research and interviews with surviving code girls, bestselling author Liza Mundy brings to life this riveting and vital story of American courage, service, and scientific accomplishment.

This book reveals the historical context and the evolution of the technically complex Allied Signals Intelligence (Sigint) activity against Japan from 1920 to 1945. It traces the all-important genesis and development of the cryptanalytic techniques used to break the main Japanese Navy code (JN-25) and the Japanese Army’s Water Transport Code during WWII. This is the first book to describe, explain and analyze the code breaking techniques developed and used to provide this intelligence, thus closing the sole remaining gap in the published accounts of the Pacific War. The authors also explore the organization of cryptographic teams and issues of security, censorship, and leaks. Correcting gaps in previous research, this book illustrates how Sigint remained crucial to Allied planning throughout the war. It helped direct the advance to the Philippines from New Guinea, the sea battles and the submarine onslaught on merchant shipping. Written by well-known authorities on the history of cryptography and mathematics, Code Breaking in the Pacific is designed for cryptologists, mathematicians and researchers working in communications security. Advanced-level students interested in cryptology, the history of the Pacific War, mathematics or the history of computing will also find this book a valuable resource.

The story of Bletchley Park, the successful intelligence operation that cracked Germany's Enigma Code. Photos.

"Historians have paid little attention to the British Army's experience with signals intelligence during the First World War. However, this was one of the Army's most important sources of information about crucial matters such as the order of battle and intentions of the German and Turkish Armies. Britain's successes and failures in signals intelligence profoundly affected battles ranging from the race for the Channel Ports, first Somme, third Gaza and Amiens, among many others." "While efforts to weed the records on these topics have created major gaps in the sources, surviving evidence throws an entirely new light on the British Army in the Great War. It allows one to trace the evolution of the Army's signals intelligence organisations, to determine many of their successes and failures, to show how this intelligence affected various operations and, indeed, to demonstrate that signals intelligence influenced the operations of the British Army as much as those of the Royal Navy." "The material reproduced in this volume includes excerpts from reports by Army Headquarters in France, Italy and Mesopotamia and the Military Intelligence Directorate. It includes the memorandum "Enemy Codes and their Solution" by the G.H.Q. codebreaking section in January 1918, which is one of the two best sources known to exist about the techniques of "codebreaking"; surviving reports on the enemy radio networks in the Balkans and Anatolian Turkey, which are the most illuminating evidence from any theatre on the approach toward "traffic analysis" and a report on the breaking of German and Turkish Army ciphers in Mesopotamia during 1917, which is the best source known about the techniques of "cryptanalysis" used by an Army in the Great War."--BOOK JACKET.Title Summary field provided by Blackwell North America, Inc. All Rights Reserved

The New York Times bestselling author of Dark Invasion and The Last Goodnight once again illuminates the lives of little-known individuals who played a significant role in America’s history as he chronicles the incredible true story of a critical, recently declassified counterintelligence mission and two remarkable agents whose story has been called "the greatest secret of the Cold War." In 1946, genius linguist and codebreaker Meredith Gardner discovered that the KGB was running an extensive network of strategically placed spies inside the United States, whose goal was to infiltrate American intelligence and steal the nation’s military and atomic secrets. Over the course of the next decade, he and young FBI supervisor Bob Lamphere worked together on Venona, a top-secret mission to uncover the Soviet agents and protect the Holy Grail of Cold War espionage—the atomic bomb. Opposites in nearly every way, Lamphere and Gardner relentlessly followed a trail of clues that helped them identify and take down these Soviet agents one by one, including Julius and Ethel Rosenberg. But at the center of this spy ring, seemingly beyond the American agents’ grasp, was the mysterious master spy who pulled the strings of the KGB’s extensive campaign, dubbed Operation Enormoz by Russian Intelligence headquarters. Lamphere and Gardner began to suspect that a mole buried deep in the American intelligence community was feeding Moscow Center information on Venona. They raced to unmask the traitor and prevent the Soviets from fulfilling Soviet Premier Nikita Khrushchev’s threat: "We shall bury you!" A breathtaking chapter of American history and a page-turning mystery that plays out against the tense, life-and-death gamesmanship of the Cold War, this twisting thriller begins at the end of World War II and leads all the way to the execution of the Rosenbergs—a result that haunted both Gardner and Lamphere to the end of their lives.