Network management device and network management method

1. A network management device comprising:

a memory in which a change rate of a transmission quality of a first optical signal to be transmitted on a first path with respect to a power of the first optical signal is stored; and

a processor coupled to the memory and the processor configured to determine, based on the change rate, whether to set a second path on which a second optical signal transmits to overlap with at least a portion of a route of the first path.

2. The network management device according to claim 1 ,

wherein the processor is configured to set the second path according to a result of determining whether to set the second path.

3. The network management device according to claim 2 ,

wherein, when the change rate is equal to or less than a predetermined value, the processor is configured to set the second path not to overlap with the route of the first path, by setting a link-selection priority for one or more links included in the first path to be lower than the link-selection priority for other links, the link-selection priority being a priority for selecting a link in setting the second path.

4. The network management device according to claim 2 ,

wherein the processor is further configured to:

control powers of the first optical signal and the second optical signal, and

measure transmission qualities of the first optical signal and the second optical signal,

wherein the change rate of the transmission quality of the first optical signal with respect to the power of the first optical signal is stored in the memory, when the transmission quality of the first optical signal is a first predetermined value, and

wherein the processor is configured to increase the power of the first optical signal, in a case where the power of the second optical signal is increased, when the measured transmission quality of the first optical signal falls below the first predetermined value.

5. The network management device according to claim 4 ,

wherein the processor is configured to delete the second path, in a case where the power of the second optical signal is increased, when the transmission quality of the measured second optical signal is deteriorated.

6. The network management device according to claim 4 ,

wherein the processor is further configured to update the change rate stored in the memory, in a case where the power of the first optical signal is increased, when the measured transmission quality of the first optical signal reaches the first predetermined value.

7. The network management device according to claim 4 ,

wherein the processor is configured to increase the power of the first optical signal in an ascending order of the change rate, in a case where a plurality of first paths exist.

8. A computer-readable non-transitory recording medium storing a program that causes a computer to execute a procedure, the procedure comprising:

storing a change rate of a transmission quality of a first optical signal to be transmitted on a first path with respect to a power of the first optical signal in a memory, and

determining, based on the change rate, whether to set a second path on which a second optical signal transmits to overlap with at least a portion of a route of the first path so as to set the second path according to a result of the determining.

9. The computer-readable non-transitory recording medium according to claim 8 ,

wherein, when the change rate is equal to or less than a predetermined value, the procedure sets the second path not to overlap with the route of the first path, by setting a link-selection priority for one or more links included in the first path to be lower than the link-selection priority for other links, the link-selection priority being a priority for selecting a link in setting the second path.

10. The computer-readable non-transitory recording medium according to claim 8 ,

wherein the procedure further comprising:

controlling powers of the first optical signal and the second optical signal, and

measuring transmission qualities of the first optical signal and the second optical signal,

wherein the change rate of the transmission quality of the first optical signal with respect to the power of the first optical signal is stored in the memory, when the transmission quality of the first optical signal is a first predetermined value, and

wherein the procedure increases the power of the first optical signal, in a case where the power of the second optical signal is increased, when the measured transmission quality of the first optical signal falls below the first predetermined value.

11. The computer-readable non-transitory recording medium according to claim 10 ,

wherein the second path is deleted, in a case where the power of the second optical signal is increased, when the transmission quality of the measured second optical signal is deteriorated.

12. The computer-readable non-transitory recording medium according to claim 10 ,

wherein the procedure further comprising:

updating the change rate stored in the memory, in a case where the power of the first optical signal is increased, when the measured transmission quality of the first optical signal reaches the first predetermined value.

13. The computer-readable non-transitory recording medium according to claim 10 ,

wherein the power of the first optical signal is increased in an ascending order of the change rate, in a case where a plurality of first paths exist.

14. A network management method comprising:

storing a change rate of a transmission quality of a first optical signal to be transmitted on a first path with respect to a power of the first optical signal in a memory, and

determining, based on the change rate, whether to set a second path on which a second optical signal transmits to overlap with at least a portion of a route of the first path, by a processor.

15. The network management method according to claim 14 ,

wherein the processor sets the second path according to a result of determining whether to set the second path.

16. The network management method according to claim 15 ,

wherein, when the change rate is equal to or less than a predetermined value, the processor sets the second path not to overlap with the route of the first path, by setting a link-selection priority for one or more links included in the first path to be lower than the link-selection priority for other links, the link-selection priority being a priority for selecting a link in setting the second path.

17. The network management method according to claim 15 , further comprising:

controlling powers of the first optical signal and the second optical signal, and

measuring transmission qualities of the first optical signal and the second optical signal, by the processor,

wherein the change rate of the transmission quality of the first optical signal with respect to the power of the first optical signal is stored in the memory, when the transmission quality of the first optical signal is a first predetermined value, and

wherein the processor increases the power of the first optical signal, in a case where the power of the second optical signal is increased, when the measured transmission quality of the first optical signal falls below the first predetermined value.

18. The network management method according to claim 17 ,

wherein the processor deletes the second path, in a case where the power of the second optical signal is increased, when the transmission quality of the measured second optical signal is deteriorated.

19. The network management method according to claim 17 ,

wherein the processor updates the change rate stored in the memory, in a case where the power of the first optical signal is increased, when the measured transmission quality of the first optical signal reaches the first predetermined value.

20. The network management method according to claim 17 ,

wherein the processor increases the power of the first optical signal in an ascending order of the change rate, in a case where a plurality of first paths exist.