摘要 |
When line trouble occurs in an optical network, the restoration time can be reduced. A transponder 21 includes an active line and a standby line 43, and a transponder 22 includes an active line 42 and a standby line 44. The standby line 44 of the transponder 22 is accommodated in the same optical line as the active line 41 of the transponder 21. Upon detection of line trouble, the receiving transponder 24 acquires a VDC setting value for the active line 41, and sets the VDC setting value for the standby line 44 on the basis of the acquired VDC setting value. |