Operator console with paired modules including means for ciphering and deciphering messages therebetween based on a mutually known, exclusive internal security code

摘要

An operator console for data communication includes a keyboard and a ciphering deciphering/unit. The console is divided into two separate units which can be connected electrically together, namely a keyboard (10) and a security module (11). The keyboard (10) includes keys (101), logical unit (21) with memory (211) and a ciphering/deciphering circuit (22). The securing module (11) includes a logical unit (31) having a memory (311), a ciphering/deciphering circuit (32), and a random generator (34) which, in conjunction with keyboard communication, randomly generates a code necessary to effect the communication and transfers this code to the keyboard memory (211) and replaces a code previously stored therein. Connected between the input side of the keyboard (10) and the memory (211) is a security circuit which disconnects a conduit (240) to the keyboard memory (211), subsequent to a first transfer of a code from the security module (11), and connects instead a further conductor (241) to the memory (211) over the ciphering/deciphering circuit (22).