Abstract: The method of controlling and/or monitoring an optical transmission of message signals over an optical line in a repeater station includes providing a device (45) for generating further optical secondary signals from the received optical secondary signals without generating a stable optical carrier signal for the secondary signals in the device (45). This device (45) includes a hybrid circuit (451) for splitting the received optical secondary signals to form a first branched optical signal portion and a second branched optical signal portion, an optical monitoring and/or control receiver (454) for generating control and/or monitoring signals (456) from the first branched optical signal portion and an optical modulating device (458) controllable by the control and/or monitoring signals.

Abstract: The invention relates to an optical communication-transmitting system for transmitting at least one useful signal with a high bit rate, which has intermediate repeaters (ZV.sub.1 -ZV.sub.n) with optical fiber amplifiers (OV.sub.ss, OV.sub.1 -OV.sub.n, OV.sub.es) and which uses at least one additional signal of a low bit rate, for example for monitoring the intermediate repeater. For a transmission system requiring small outlay, the additional signal is transmitted on a wide band in comparison to the useful signal, for example by means of luminescence diodes (S.sub.ss, S.sub.1 -S.sub.n) and is amplified by the fiber amplifiers (OV.sub.ss, OV.sub.1 -OV.sub.n, OV.sub.es) in the same manner as the useful signal. For transmitting and receiving the additional signal, a transmitter (S.sub.1) is preferably disposed in an intermediate receiver (ZV.sub.1) upstream of the fiber amplifier (OV.sub.1) and a receiver preferably downstream thereof.