Monitoring system and monitoring method

1. A monitoring system for a transmission line for transmitting an optical wavelength multiplexed signal between a local station and an opposed station, the monitoring system comprising:

a first monitor unit that measures an optical power of an optical signal associated with an optical wavelength multiplexed signal transmitted by the local station;

a second monitor unit that measures an optical power of an optical signal associated with an optical wavelength multiplexed signal received by the local station; and

a monitoring control unit that performs monitoring by transmitting transponder wavelength information and dummy optical wavelength information about the local station to the first monitor unit, checking an optical power of a wavelength slot of a same wavelength as a wavelength designated in the transponder wavelength information and the dummy optical wavelength information measured by the first monitor unit, also transmitting transponder wavelength information and dummy optical wavelength information about the opposed station to the second monitor unit, and checking an optical power of a wavelength slot of a same wavelength as a wavelength designated in the transponder wavelength information and the dummy optical wavelength information measured by the second monitor unit.

2. The monitoring system according to claim 1 , further comprising:

a third monitor unit that measures an optical power of an optical wavelength multiplexed signal received by the opposed station; and

a fourth monitor unit that measures an optical power of an optical wavelength multiplexed signal received by the local station.

3. The monitoring system according to claim 2 , wherein the monitoring control unit transmits transponder wavelength information and dummy optical wavelength information about the local station to the third monitor unit, checks an optical power of a wavelength slot of a same wavelength as a wavelength designated in the transponder wavelength information and the dummy optical wavelength information measured by the third monitor unit, also transmits transponder wavelength information and dummy optical wavelength information about the opposed station to the fourth monitor unit, and checks an optical power of a wavelength slot of a same wavelength as a wavelength designated in the transponder wavelength information and the dummy optical wavelength information measured by the fourth monitor unit.

4. The monitoring system according to claim 1 , wherein the first monitor unit checks the optical power by using an optical wavelength multiplexed signal obtained by multiplexing the dummy light and an optical signal from a transponder of the local station, and the second monitor unit checks the optical power by using an optical wavelength multiplexed signal obtained by multiplexing the dummy light and an optical signal from a transponder of the opposed station.

5. The monitoring system according to claim 4 , further comprising a multiplexing unit that multiplexes the dummy light and an optical signal from a transponder of the local station and generates the optical wavelength multiplexed signal.

6. The monitoring system according to claim 4 , further comprising a multiplexing unit that multiplexes the dummy light and an optical signal from a transponder of the opposed station and generates the optical wavelength multiplexed signal.

7. The monitoring system according to claim 5 , wherein the multiplexing unit includes an active filter, and the active filter is controlled to have a filter shape that transmits a signal according to the transponder wavelength information from the monitoring control unit.

8. The monitoring system according to claim 1 , wherein the first monitor unit checks the optical power by using the dummy light and an optical signal from a transponder of the local station.

9. The monitoring system according to claim 1 , wherein the second monitor unit checks the optical power by using an optical wavelength multiplexed signal obtained by multiplexing the dummy light and an optical signal from a transponder of the opposed station.

10. A monitoring method for a transmission line for transmitting an optical wavelength multiplexed signal between a local station and an opposed station, the monitoring method comprising:

transmitting transponder wavelength information and dummy optical wavelength information about the local station to a first monitor unit that measures an optical power of an optical signal associated with an optical wavelength multiplexed signal transmitted by the local station, and checking an optical power of a wavelength slot of a same wavelength as a wavelength designated in the transponder wavelength information and the dummy optical wavelength information measured by the first monitor unit; and

transmitting transponder wavelength information and dummy optical wavelength information about the opposed station to a second monitor unit that measures an optical power of an optical signal associated with an optical wavelength multiplexed signal received by the local station, and checking an optical power of a wavelength slot of a same wavelength as a wavelength designated in the transponder wavelength information and the dummy optical wavelength information measured by the second monitor unit.

11. The monitoring method for the transmission line according to claim 10 , further comprising:

transmitting transponder wavelength information and dummy optical wavelength information about the local station to a third monitor unit that measures an optical power of an optical wavelength multiplexed signal received by the opposed station;

checking an optical power of a wavelength slot of a same wavelength as a wavelength designated in the transponder wavelength information and the dummy optical wavelength information measured by the third monitor unit;

transmitting transponder wavelength information and dummy optical wavelength information about the opposed station to a fourth monitor unit that measures an optical power of an optical wavelength multiplexed signal received by the local station; and

checking an optical power of a wavelength slot of a same wavelength as a wavelength designated in the transponder wavelength information and the dummy optical wavelength information measured by the fourth monitor unit.

12. The monitoring method for the transmission line according to claim 10 , wherein the first monitor unit checks the optical power by using an optical wavelength multiplexed signal obtained by multiplexing the dummy light and an optical signal from a transponder of the local station, and

the second monitor unit checks the optical power by using an optical wavelength multiplexed signal obtained by multiplexing the dummy light and an optical signal from a transponder of the opposed station.

13. The monitoring method for the transmission line according to claim 10 , wherein the first monitor unit checks the optical power by using the dummy light and an optical signal from a transponder of the local station.

14. The monitoring method for the transmission line according to claim 10 , wherein the second monitor unit checks the optical power by using an optical wavelength multiplexed signal obtained by multiplexing the dummy light and an optical signal from a transponder of the opposed station.

15. A non-transitory computer-readable recording medium to record monitoring program for a transmission line for transmitting an optical wavelength multiplexed signal between a local station and an opposed station,

the monitoring program causing a computer to execute:

control processing for transmitting transponder wavelength information and dummy optical wavelength information about the local station to a first monitor means for measuring an optical power of an optical signal associated with an optical wavelength multiplexed signal transmitted by the local station;

monitoring processing for checking an optical power of a wavelength slot of a same wavelength as a wavelength designated in the transponder wavelength information and the dummy optical wavelength information measured by the first monitor means;

control processing for transmitting transponder wavelength information and dummy optical wavelength information about the opposed station to a second monitor means for measuring an optical power of an optical signal associated with an optical wavelength multiplexed signal received by the local station; and

monitoring processing for checking an optical power of a wavelength slot of a same wavelength as a wavelength designated in the transponder wavelength information and the dummy optical wavelength information measured by the second monitor means.

16. The non-transitory computer-readable recording medium to record monitoring program for the transmission line according to claim 15 , further causing the computer to execute:

control processing for transmitting transponder wavelength information and dummy optical wavelength information about the local station to a third monitor means for measuring an optical power of an optical wavelength multiplexed signal received by the opposed station;

monitoring processing for checking an optical power of a wavelength slot of a same wavelength as a wavelength designated in the transponder wavelength information and the dummy optical wavelength information measured by the third monitor means;

control processing for transmitting transponder wavelength information and dummy optical wavelength information about the opposed station to a fourth monitor means for measuring an optical power of an optical wavelength multiplexed signal received by the local station; and

monitoring processing for checking an optical power of a wavelength slot of a same wavelength of a wavelength designated in the transponder wavelength information and the dummy optical wavelength information measured by the fourth monitor means.

17. The non-transitory computer-readable recording medium to record monitoring program for the transmission line according to claim 15 , wherein the first monitor means checks the optical power by using an optical wavelength multiplexed signal obtained by multiplexing the dummy light and an optical signal from a transponder of the local station, and

the second monitor means checks the optical power by using an optical wavelength multiplexed signal obtained by multiplexing the dummy light and an optical signal from a transponder of the opposed station.

18. The non-transitory computer-readable recording medium to record monitoring program for the transmission line according claim 15 , wherein the first monitor means checks the optical power by using the dummy light and an optical signal from a transponder of the local station.

19. The non-transitory computer-readable recording medium to record monitoring program for the transmission line according claim 15 , wherein the second monitor means checks the optical power by using an optical wavelength multiplexed signal obtained by multiplexing the dummy light and an optical signal from a transponder of the opposed station.