Optical node device, optical transport network system, optical path trace method and program

Patent metadata

Field	Value
Publication number	US-2023254611-A1
Application number	US-202018014292-A
Country	US
Kind code	A1
Filing date	Jul 6, 2020
Priority date	Jul 6, 2020
Publication date	Aug 10, 2023
Grant date	—

Abstract

An optical node device (1aA to 1cA) includes a transmission transponder (27), WSSs (22 to 25), a beam splitter (21), and a monitoring transponder (26). The transmission transponder (27) transmits an optical signal (B1) via an optical path (P3) set in an optical fiber (2). The WSSs (22 to 25) multiplex, on the transmitted optical signal (B1), a monitoring control signal (M1) for performing optical path tracing that is confirmation of conduction along the optical path (P3). The monitoring transponder (26) measures and monitors the optical power of the monitoring control signal (M1) multiplexed into the optical signal (B1) branched by the beam splitter (21), and further monitors whether the monitored optical power is equal to or higher than a predetermined level indicating normality of the optical path (P3).

First claim

1 . An optical node device comprising:
a transmission transponder configured to transmit an optical signal via an optical path extended over an optical fiber; a wavelength selective switch (WSS) configured to multiplex, on the transmitted optical signal, a monitoring control signal for performing optical path tracing that is confirmation of conduction along the optical path; a branching unit configured to branch the optical signal in which the monitoring control signal is multiplexed; and a monitoring transponder configured to measure and monitor optical power of the monitoring control signal multiplexed into the optical signal branched by the branching unit, wherein the monitoring transponder configured to monitor whether the monitored optical power is equal to or higher than a predetermined level indicating normality of the optical path.

2 . The optical node device according to claim 1 , wherein the WSS includes
an optical channel monitor configured to, when multiplexing the monitoring control signal with the optical signal, multiplex the monitoring control signal including unique optical path identification (ID) information, and
monitor the optical path ID information obtained by reading and demodulating a temporal change of the optical power of the monitoring control signal multiplexed on the optical signal branched by the branching unit, and
wherein the optical channel monitor monitors is configured to monitor the normality of the optical path between the transmission transponder and the branching unit branching the optical signal based on the optical path ID information.

3 . The optical node device according to claim 1 , wherein the WSS includes
an input collimator to which the optical signal is configured to be input, a diffraction grating configured to receive the optical signal through the input collimator, diffract the optical signal at a different angle according to a wavelength of the optical signal, reflect the optical signal, and demultiplex the optical signal, a spatial light modulator configured to reflect the demultiplexed optical signal and apply a voltage of the monitoring control signal to the optical signal at the time of reflection to apply intensity modulation, and an output collimator configured to output the optical signal reflected by the spatial light modulator.

4 . An optical transport network system, wherein
the optical node device according to claim 1 is subordinately connected by an optical fiber via the branching unit.

5 . The optical transport network system according to claim 4 , wherein
a monitoring control signal with unique optical path ID information is multiplexed into an optical signal to be transmitted on the optical path in each of the WSSs on the optical path extended between the subordinately connected optical node device.

6 . An optical path tracing method by an optical node device, comprising:
transmitting an optical signal via an optical path extended over an optical fiber, multiplexing, on the transmitted optical signal, a monitoring control signal for performing optical path tracing that is confirmation of conduction along the optical path, branching the optical signal in which the monitoring control signal is multiplexed, measuring and monitoring optical power of the monitoring control signal multiplexed into the optical signal, and monitoring whether the monitored optical power is equal to or higher than a predetermined level indicating normality of the optical path.

7 . A non-transitory computer readable medium storing a program, wherein executing of the program causes a computer to function as the optical node device according to claim 1 .

8 . The optical node device according to claim 2 , wherein the WSS includes
an input collimator to which the optical signal is configured to be input, a diffraction grating configured to receive the optical signal through the input collimator, diffract the optical signal at a different angle according to a wavelength of the optical signal, reflect the optical signal, and demultiplex the optical signal, a spatial light modulator configured to reflect the demultiplexed optical signal and apply a voltage of the monitoring control signal to the optical signal at the time of reflection to apply intensity modulation, and an output collimator configured to output the optical signal reflected by the spatial light modulator.

9 . An optical transport network system, wherein the optical node device according to claim 2 is subordinately connected by an optical fiber via the branching unit.

10 . An optical transport network system, wherein the optical node device according to claim 3 is subordinately connected by an optical fiber via the branching unit.

11 . A non-transitory computer readable medium storing a program, wherein executing of the program causes a computer to function as the optical node device according to claim 2 .

12 . A non-transitory computer readable medium storing a program, wherein executing of the program causes a computer to function as the optical node device according to claim 3 .

Assignees

• Nippon Telegraph & Telephone

Inventors

• Kawahara Hiroki
• Seki Takeshi
• Suda Sachio
• Saito Kohei

Classifications

• H04B10/40

  Transceivers · CPC title

• H04B10/60

  Receivers · CPC title

• H04B10/50

  Transmitters · CPC title

• H04Q11/0005 Primary

  Switch and router aspects · CPC title

• H04Q11/0062 Primary

  Network aspects · CPC title