| 摘要 |
PROBLEM TO BE SOLVED: To simplify the configuration of a branching device, to reduce scale and to prevent the branching loss of each path inside the branching device from being changed concerning a multiplex wavelength transmitting system having the branching device. SOLUTION: Terminal stations 19 and 20 are communicable in wavelengths λ1 and λ2 , terminal stations 20 and 21 are communicable in wavelengths λ3 and λ4 , terminal stations 21 and 19 are communicable in wavelengths λ5 and λ6 and usually, communication is performed by using 1, 3 and 5. When any fault is generated between a branching device 22 and the terminal station 21, a transmission/reception part at the terminal station 19 switches the wavelength λ5 to λ2 and a transmission/reception part at the terminal station 20 switches the wavelength λ3 to λ2 . Thus, a transmission line between the terminal stations 19 and 20 is added by the wavelength λ2 and the communication between the terminal stations 20 and 21 and between the terminal stations 21 and 19 can be secured by using another path. |
