| 摘要 |
Provided is an optical network system which includes a higher network device, a lower network device, and multiple delivery network devices, each of which interconnects the higher network device and the lower network device through an independent optical link, wherein the lower network device switches to transmit and receive an optical signal through an optical link of a spare line when a failure occurs in at least one of an optical link used as a main line, an optical interface apparatus related to the main line in the higher network device, and a delivery network device related to the main line. |
