Circuit and method for generating a true, circuit-specific and time-invariant random number

The invention relates to a circuit for generating a true, circuit-specific and time-invariant random binary number, having: a matrix of K−L delay elements that can be connected to each other by means of L−1 single or double commutation circuits into chains of delay elements of length L, a single or double demultiplexer connected before the matrix, a single or double multiplexer connection after the matrix, and a run time or number comparator, wherein the setting of the commutation circuits, the demultiplexer, and the multiplexer can be prescribed by a control signal, wherein the circuit comprises a channel code encoder whereby code words of a channel code can be generated and a transcriber, whereby code words of the channel code can be transcribed into the control signal of the L−1 single or double commutation circuits, and a method for generating a true, circuit-specific and time-invariant random number by means of a matrix of L−K delay elements, L−1 single or double commutation circuits, a single or double demultiplexer connected before the matrix, a single or double multiplexer connection after the matrix, and a run time or number comparator, comprising at least the steps a) generating a code word of a channel code, b) transcribing a code word of a channel code to a selection code, c) generating chains of L delay elements by setting a setting corresponding to the code word of the selection code for the L−1 single or double commutation circuits, the single or double demultiplexer, and the single or double multiplexer, d) pairwise comparing of two variables determined by the delay times of two chains defined by the setting of the L−1 commutation circuits corresponding to the code word of the channel code, by means of a number or delay comparator for generating a bit of the true, circuit-specific and time-invariant random number.