Optical transmission system

摘要

An optical transmission system which is capable of improving the stability of the system by appropriately adjusting a transmission data format and a transmitted optical output when a fault occurs on a transmission path, when a terminal is initiated, or when the transmission path is recovered from a fault. The optical transmission system comprises a first test signal supplying means responsive to a detection of erroneous contents in a received signal received through the optical transmission path for supplying a test signal to the optical transmission path, a second test signal supplying means responsive to a detection of a received signal received through the optical transmission path, which is equal to a test signal, and a communication stopping means for stopping the transmission/reception of a signal through the optical transmission path when a frequency at which the erroneous contents are detected or a frequency at which the test signal is detected exceeds a predetermined threshold.