Editing NSA encryption systems (section)

=== Third generation: integrated circuits ===

[[File:KOI-18.nsa.jpg|thumb|[[KOI-18]] field paper tape reader]]

Third generation systems (1980s) were transistorized and based on [[integrated circuit]]s and likely used stronger algorithms. They were smaller and more reliable. Field maintenance was often limited to running a diagnostic mode and replacing a complete bad unit with a spare, the defective cipher device being sent to a depot for repair. Keys were loaded through a connector on the front panel. NSA adopted the same type of connector that the military used for field radio handsets as its fill connector. Keys were initially distributed as strips of [[punched tape|punched paper tape]] that could be pulled through a hand held reader ([[KOI-18]]) connected to the fill port. Other, portable electronic [[fill device]]s ([[KYK-13]], etc.) were available as well.