Apparatus for simultaneous generation of key at two locations

摘要

An apparatus for simultaneously generating identical cipher key at two remote terminals in a manner which prohibits interception of the key by unauthorized persons. A circuit comprising three separate wire lines is connected between the two terminals over geographically separated routes. The circuit is randomly completed and broken by a switch at each terminal, the switch position being determined at each terminal by an independent key generator. Cipher key is communicated by comparing the key generator output and the circuit condition.