what does sigint mean
oh nvm i have answers on my firefox:
SIGINT (
signals intelligence) is the monitoring, collection, and analysis of communications intelligence and covers the monitoring of radio and telephone
message traffic and the decryption and analysis of coded messages. The
related but separate activity known as electronic intelligence (ELINT)
mainly covers the detection and analysis of radar, telemetry, and other non-communication signals to discover performance parameters and develop countermeasures.
During WW I, listening to and jamming enemy signals became routine. SIGINT enabled the German army to crush the Russians at Tannenberg and the Masurian Lakes, and also enabled the British Admiralty to intercept the German High Seas fleet at the Dogger Bank and Jutland.
The opposing armies were so close to each other on the western front
that with primitive crystal-set receivers they could pick up the
traffic passing over telegraph and telephone wires through electrical
induction. Personnel on both sides were responsible for locating enemy
transmitters, monitoring transmissions, and intercepting and
deciphering enemy traffic.
During WW II, ULTRA gave the Allies an inestimable advantage over the Axis, although the Abwehr
also broke the Royal Navy codes. The US Army Signal Corps developed an
automatic machine for enciphering and deciphering Morse messages called
SIGABA which, unlike Enigma
and the Japanese system, was never broken. Another US development was
the radio telephone system called SIGSALY. A third security system
developed during the war was the SIGTOT and the British TYPEX which
permitted two-way teletype conferences—both were reserved for senior
commanders.
The Achilles' heel of SIGINT arises both from the
perishability of the product and the fact that if it is acted upon too
openly, the source will likely dry up as the enemy finds less
vulnerable means of communication. This was a major difficulty in the
use of the information provided by ULTRA (see Crete, battle of).
During the latter part of the Cold War,
thanks to the treachery of the Walker family and friends, the Soviets
could read all US navy traffic, which might have been an advantage akin
to ULTRA if it had ever become hot. All other nations must work on the
assumption that major SIGINT and ELINT establishments such as those
maintained by the USA, Russia, and the UK can read all their
communications if they wish to. In general any machine encipherment
system can be broken if sufficient computer time is devoted to it,
hence modern military communications are protected only for the
notional length of time (against computer attack) necessary to preserve
operational secrecy. This can be quite brief.
Bibliography
- Bauer, F. L., Decrypted Secrets: Methods and Maxims of Cryptology (New York, 1997).
- Kahn, David, The Codebreakers: The Story of Secret Writing (rev. edn., New York, 1996)
— Danny M. Johnson/Hugh Bicheno