ECHELONECHELON, originally a secret government code name, is a surveillance program (signals intelligence/SIGINT collection and analysis network) operated by the five signatory states to the UKUSA Security Agreement: Australia, Canada, New Zealand, the United Kingdom and the United States, also known as the Five Eyes. Created in the late 1960s to monitor the military and diplomatic communications of the Soviet Union and its Eastern Bloc allies during the Cold War, the ECHELON project became formally established in 1971.
High-frequency direction findingHigh-frequency direction finding, usually known by its abbreviation HF/DF or nickname huff-duff, is a type of radio direction finder (RDF) introduced in World War II. High frequency (HF) refers to a radio band that can effectively communicate over long distances; for example, between U-boats and their land-based headquarters. HF/DF was primarily used to catch enemy radios while they transmitted, although it was also used to locate friendly aircraft as a navigation aid.
Traffic analysisTraffic analysis is the process of intercepting and examining messages in order to deduce information from patterns in communication. It can be performed even when the messages are encrypted. In general, the greater the number of messages observed, the greater information be inferred. Traffic analysis can be performed in the context of military intelligence, counter-intelligence, or pattern-of-life analysis, and is also a concern in computer security. Traffic analysis tasks may be supported by dedicated computer software programs.
Attack on Pearl HarborThe attack on Pearl Harbor was a surprise military strike by the Imperial Japanese Navy Air Service upon the United States against the U.S. naval base at Pearl Harbor in Honolulu, Hawaii, just before 8:00a.m. (local time) on Sunday, December 7, 1941. The United States was a neutral country at the time; the attack led to its formal entry into World War II on the side of the Allies the next day. The Japanese military leadership referred to the attack as the Hawaii Operation and Operation AI, and as Operation Z during its planning.
BombeThe bombe (UKbɒmb) was an electro-mechanical device used by British cryptologists to help decipher German Enigma-machine-encrypted secret messages during World War II. The US Navy and US Army later produced their own machines to the same functional specification, albeit engineered differently both from each other and from Polish and British bombes. The British bombe was developed from a device known as the "bomba" (bomba kryptologiczna), which had been designed in Poland at the Biuro Szyfrów (Cipher Bureau) by cryptologist Marian Rejewski, who had been breaking German Enigma messages for the previous seven years, using it and earlier machines.
Y serviceThe "Y" service was a network of British signals intelligence collection sites, the Y-stations. The service was established during the First World War and used again during the Second World War. The sites were operated by a range of agencies including the Army, Navy and RAF plus the Foreign Office (MI6 and MI5), General Post Office and Marconi Company receiving stations ashore and afloat. There were more than 600 receiving sets in use at Y-stations during the Second World War.
Code talkerA code talker was a person employed by the military during wartime to use a little-known language as a means of secret communication. The term is most often used for United States service members during the World Wars who used their knowledge of Native American languages as a basis to transmit coded messages. In particular, there were approximately 400 to 500 Native Americans in the United States Marine Corps whose primary job was to transmit secret tactical messages.
United States Department of DefenseThe United States Department of Defense (DoD, USDOD, or DOD) is an executive branch department of the federal government of the United States charged with coordinating and supervising all agencies and functions of the U.S. government directly related to national security and the United States Armed Forces. As of June 2022, the U.S. Department of Defense is the largest employer in the world, with over 1.34 million active-duty service members, including soldiers, marines, sailors, airmen, and guardians.
Intelligence agencyAn intelligence agency is a government agency responsible for the collection, analysis, and exploitation of information in support of law enforcement, national security, military, public safety, and foreign policy objectives. Means of information gathering are both overt and covert and may include espionage, communication interception, cryptanalysis, cooperation with other institutions, and evaluation of public sources. The assembly and propagation of this information is known as intelligence analysis or intelligence assessment.
Reconnaissance satelliteA reconnaissance satellite or intelligence satellite (commonly, although unofficially, referred to as a spy satellite) is an Earth observation satellite or communications satellite deployed for military or intelligence applications. The first generation type (i.e., Corona and Zenit) took photographs, then ejected canisters of photographic film which would descend back down into Earth's atmosphere. Corona capsules were retrieved in mid-air as they floated down on parachutes.
