Multiplexer cell for cryptography circuit for data communications has 3 elementary multiplexers in 2 successive stages one of which is controlled by encryption control signal

摘要

The multiplexer cell (50,50') has 2 data inputs (52A,52B), a control input (54), a key input (56) and a data output (57), both data inputs coupled to a pair of first elementary multiplexers (58,60), their outputs coupled to the data output via a second elementary multiplexer (62). An Exclusive-OR gate (64) is inserted between the control input and the multiplexer cell. Also included are Independent claims for the following: (a) a device for provision of an input value from an encrypted output value; (b) a method for switching 2 data signals at respective data inputs to a data output.