Disclosed is a method for generating a secret or a key in a network (20). The network (20) comprises at least a first subscriber (21) and a second subscriber (22) and a common transmission channel (30) between at least the first (21) and second subscribers (22). The first subscriber (21) can output at least a first value (1) and a second value (0) and the second subscriber (22) can output at least the first value (1) and the second value (0) on the transmission channel, the first subscriber (21) generating a first sequence of subscriber values and the second subscriber (22) generating a second sequence of subscriber values in order for the transmission to occur largely synchronously on the transmission channel (30); and the first subscriber (21) and the second subscriber (22) each generate a common secret or a common key, the first subscriber (21) doing so on the basis of information about the first sequence of subscriber values and on the basis of a sequence of superposed values resulting from a superposition of the second sequence of subscriber values onto the first sequence of subscriber values on the transmission channel (30), and the second subscriber (22) doing so on the basis of information about the second sequence of subscriber values and on the basis of the sequence of superposed values resulting from the superposition of the second sequence of subscriber values onto the first sequence of subscriber values on the transmission channel (30). At least the first subscriber (21) and the second subscriber (22) determine a sequence of test values in accordance with the resulting sequence of superposed values and output same on the transmission channel (30).