JP6335110B2 - Optical transmission apparatus and optical signal transmission method - Google Patents

Description

  The present invention relates to an optical transmission device and an optical signal transmission method.

  An OTN (Optical Transport Network) which is a large-capacity wide-area optical transport network accommodates and transfers various client signals such as SDH (Synchronous Digital Hierarchy) and Ethernet (registered trademark). In recent years, the increase in traffic of client signals has been remarkable, and along with this, standardization has been advanced so that OTN can cope with higher speed (for example, see Non-Patent Document 1). Currently, OTUCn (Cn represents 100G × n), which is an OTN technology exceeding 100 G (B100G, G is gigabit per second), is being studied (for example, see Non-Patent Document 2). In OTUCn, the transmission capacity of one optical channel is wider than that of a conventional OTU. However, due to the relationship between the operating speeds of electronic circuits used in optical signal transceivers, it is difficult to increase the capacity by expanding single carrier transmission in the band of one optical channel as in the past. Therefore, in OTUCn, a large capacity is realized by multicarrier transmission using a plurality of optical subcarriers in a band of one optical channel.

"Interfaces for the optical transport network", ITU-T G.709 / Y.1331, February 2012. Takuya Ohara, “OTN Interface Technology and Standardization Trends”, 2014 IEICE General Conference, Proceedings of the IEICE Communication Conference 2, BI-5-1, SS-47-SS-48, March 2014

  The OTUCn framer interleaves an OTUCn (Optical channel Transport Unit-Cn) electrical signal with a payload capacity of n × 100 G, and is a parallel signal with a payload capacity of 100 G. Generate n (Optical channel Transport Lane-Cn.n) n. The n parallel signals for one optical channel generated by the framer are converted into optical signals by a plurality of transmitters for multicarrier transmission using a plurality of optical subcarriers. Therefore, there is a possibility that the failure rate of the transmitter per optical channel is higher than that of single carrier transmission in which a single transmitter transmits a signal of one optical channel.

  In view of the above circumstances, the present invention provides an optical transmission device and an optical signal transmission method capable of improving reliability against a transmitter failure when a plurality of parallel signals are transmitted by a plurality of transmitters by a multicarrier. The purpose is that.

  One embodiment of the present invention provides an optical signal including a plurality of optical signal transmission units each including a framer that generates a plurality of parallel signals, and a plurality of transmitters that transmit the plurality of parallel signals generated by the framer using optical subcarriers. A transmission apparatus, comprising: a wavelength switching unit that instructs the switching destination transmitter to use a wavelength used by the transmitter in which the failure has occurred for transmission of an optical subcarrier, and the transmitter in which the failure has occurred The framer of the first optical signal transmission unit, which is the optical signal transmission unit including the first optical signal transmission unit, is a part of the client signal received from one or more clients. Based on the client signal that is output to the two-optical signal transmission unit and that is obtained by removing a part of the client signal output to the second optical signal transmission unit from the received client signal. A first optical signal generation unit that generates a parallel signal and outputs the parallel signal in which the client signal is set to the transmitter in which a failure of the first optical signal transmission unit does not occur, The framer of the optical signal transmission unit generates a parallel signal based on the client signal received from the framer of the first optical signal transmission unit, and outputs the generated parallel signal to the switching destination transmitter. An optical transmission device including a two-optical signal generation unit.

  One aspect of the present invention is the above-described optical transmission device, wherein the first optical signal generation unit excludes a part of the client signal output to the second optical signal transmission unit from the received client signal. A first multiplex processing unit configured to set the client signal in the time slot corresponding to the transmitter in which a failure of the first optical signal transmission unit has not occurred among time slots in a signal frame; The signal frame in which the client signal is set is divided by one multiplex processing unit to generate a plurality of parallel signals, and the parallel signal in which the client signal is set is output to the transmitter in which no failure has occurred A first parallel signal generator configured to transmit the client signal received from the framer of the first optical signal transmitter. A second multiplex processing unit that sets the time slot corresponding to the transmitter to be switched among the time slots in the frame; and the signal frame in which the client signal is set by the second multiplex processing unit. And a second parallel signal generation unit configured to generate a plurality of parallel signals by dividing and output the parallel signal in which the client signal is set to the switching destination transmitter.

  One aspect of the present invention is the above-described optical transmission device, wherein the client path is assigned to the time slot in the signal frame, and the first multiplex processing unit has a failure in the signal frame. The client signal of the client to which a path is assigned to the time slot corresponding to the generated transmitter is output to the second optical signal transmitter.

  One aspect of the present invention is the above-described optical transmission device, wherein the first multiplex processing unit and the second multiplex processing unit each correspond to the time slot corresponding to the transmitter in which a failure has occurred in the signal frame. The path assignment destination of the client assigned to is changed to the time slot corresponding to the transmitter of the switching destination in the signal frame used by the second optical signal generation unit. .

  One aspect of the present invention is the above-described optical transmission device, which uses the optical subcarrier in which the failure has occurred by receiving information on the optical subcarrier in which the failure has occurred from the optical transmission device on the receiving side. A failure detection unit is provided that detects occurrence of a transmitter failure and notifies the first optical signal transmission unit of information on the transmitter in which the failure has occurred and the switching destination transmitter.

  One aspect of the present invention is the above-described optical transmission device, which includes a wavelength multiplexing function unit that has a colorless function and multiplexes the optical subcarriers output from each of the plurality of transmitters. It is characterized by.

  One aspect of the present invention is the above-described optical transmission device, wherein each of the plurality of transmitters includes a port that outputs the optical subcarrier to the wavelength multiplexing function unit.

  One embodiment of the present invention provides an optical signal including a plurality of optical signal transmission units each including a framer that generates a plurality of parallel signals, and a plurality of transmitters that transmit the plurality of parallel signals generated by the framer using optical subcarriers. An optical signal transmission method executed by a transmission apparatus, wherein the optical transmission apparatus instructs the transmitter to be switched to use a wavelength used by the transmitter in which a failure has occurred to transmit an optical subcarrier. The wavelength switching step and the framer of the first optical signal transmission unit which is the optical signal transmission unit having the transmitter in which the failure has occurred, part of the client signal received from one or more clients, the switching destination Output to the second optical signal transmitter, which is the optical signal transmitter including the transmitter, and a part of the class output from the received client signal to the second optical signal transmitter. A parallel signal is generated based on the client signal excluding an ant signal, and the parallel signal in which the client signal is set is output to the transmitter in which no failure of the first optical signal transmission unit has occurred. A signal generation step; and the framer of the second optical signal transmitter generates a parallel signal based on the client signal received from the framer of the first optical signal transmitter, and the generated parallel signal is switched to A second signal generation step of outputting to the transmitter.

  According to the present invention, when a plurality of parallel signals are multi-carrier transmitted by a plurality of transmitters, it is possible to improve the reliability against a transmitter failure.

It is a functional block diagram of the framer which can apply embodiment of this invention. It is a figure which shows the frame structure of OTUCn. OTLCn. It is a figure which shows the frame structure of n. It is a figure which shows the optical channel used for transmission of an optical signal. It is a figure which shows the structural example of the optical transmission apparatus by one Embodiment of this invention. It is a figure which shows the example of the mapping of the path | route to the ODUCn frame in a normal operation state. It is a figure which shows the example of the mapping of the path | route to the ODUCn frame at the time of optical SC transmitter / receiver failure. It is a figure which shows the example of the mapping of the path | route to the ODUCn frame at the time of multiple optical SC transmitter / receiver failure. It is a figure which shows the example of the mapping of the path | route to the ODUCn frame in a normal operation state in the case of transmitting a some parallel signal with 1 optical subcarrier. It is a figure which shows the example of the mapping of the path | route to the ODUCn frame at the time of optical SC transmitter / receiver failure in the case of transmitting a some parallel signal with 1 optical subcarrier. It is a functional block diagram which shows the structure of a NNI card. It is a functional block diagram which shows the structure of a transponder. It is a processing flow of the optical transmission apparatus of the transmission side at the time of optical SC transceiver failure.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a functional block diagram of an OTN framer 800 to which an embodiment of the present invention can be applied. The OTN framer 800 shown in the figure is an OTN (Optical Transport Network) standard OTUCn (Cn represents 100G × n, where n is 2 or more) for transmission of more than 100G (B100G, G is gigabit per second). (Integer). In the figure, an example in which n = 4, that is, a case where the OTN framer 800 performs communication by OTUC4 is shown.

  In the OTN transport technology, client signals of various communication methods are accommodated and transferred by optical transmission. In OTN, a fixed frame structure is used, and ODU0 (ODU: Optical Channel Data Unit), which is the smallest unit capable of accommodating GbE (Gigabit Ethernet (registered trademark)), is also referred to as a 1.25G TS (Tributary Slot, time slot). .) Handle client signals in units (ie by multiples thereof). The OTN provides the same path management, OAM (Operations, Administration, Maintenance) function, and protection function as SDH (Synchronous Digital Hierarchy).

  The OTN framer 800 separates an n × 100G optical channel signal in which a plurality of client signals are multiplexed, and generates n 100G parallel signals. These n parallel signals are multi-carrier transmitted by a plurality of optical subcarriers, but physically one parallel signal may be transmitted by one optical subcarrier, and a plurality of parallel signals are one It may be transmitted by an optical subcarrier. Multi-carrier transmission is a communication method for increasing the capacity of one channel by transmitting a signal of one channel in parallel using a plurality of subcarriers (carrier waves). In multicarrier transmission, subcarriers are densely multiplexed for each ground (connection destination) and electrically separated. When one parallel signal is transmitted by one optical subcarrier, the bandwidth of the optical subcarrier is 100G, and when two parallel signals are transmitted by one optical subcarrier, the bandwidth of the optical subcarrier is 200G. For optical transmission, 4SC-DP-QPSK (4 Subcarrier-Dual Polarization-Quadrature Phase Shift Keying), 2SC-DP-16QAM (2 Subcarrier-Dual Polarization-Quadrature Amplitude Modulation), or the like is used.

As illustrated in FIG. 1, the OTN framer 800 includes a transmission processing unit 110 and a reception processing unit 150.
The transmission processing unit 110 includes a client signal receiving unit 120, a multiprocessing unit 130, and a line side transmission processing unit 140.

The client signal receiving unit 120 includes a receiving unit 121, a mapping unit 122, and an OH processing unit 123.
The receiving unit 121 receives a client signal. The mapping unit 122 maps one client signal received by the receiving unit 121 to a payload of a LO ODU (Lower Order Optical Channel Data Unit) frame. The OH processing unit 123 adds OH (overhead) to the LO ODU frame in which the mapping unit 122 sets the client signal. The OH processing unit 123 outputs an electric path signal of the LO ODU frame to the ODU-switch (hereinafter referred to as “ODU-SW”) 210. The ODU-SW 210 is also connected to another OTN framer 800 and performs path exchange of electric path signals.

  The multiprocessing unit 130 includes a multiplexing unit 131 and a framing unit 132. The multiplexing unit 131 sets the electrical path signal received from the ODU-SW 210 in the LO ODU frame. The multiplexing processing unit 130 once maps the LO ODU frame to an ODTU (Optical Channel Data Tributary Unit) frame, and then time-multiplexes the plurality of ODTU frames to generate an ODUCn frame that is a HO ODU (Higher Order ODU). The framing unit 132 adds OH and FEC (Forward Error Correction) to the ODUCn frame generated by the multiprocessing unit 130 to generate an OTUCn frame. The framing unit 132 outputs the signal of the OTUCn frame to the line side transmission processing unit 140.

The line side transmission processing unit 140 includes an interleaving unit 141, OH processing units 142-1 to 142-n, and multilane transmission units 143-1 to 143-n.
The interleaving unit 141 receives an OTUCn frame signal from the multiprocessing unit 130, byte-interleaves the received n × 100G OTUCn frame signal, and generates n OTLCn. An n-frame signal is generated. OTLCn. The n frame is a frame of a 100 G parallel signal. i-th OTLCn. n frames, OTLCn. n # i frame (where i is an integer from 1 to n). The interleaving unit 141 includes the generated n OTLCn. Each n # i frame is output to the OH processing unit 142-i.

The OH processing units 142-1 to 142-n receive the OTLCn. Set OH to n frames. The OH processing unit 142-i is an OTLCn. The n # i frame is output to the multilane transmission unit 143-i.
The multilane transmission units 143-1 to 143-n receive the OTLCn. The n-frame parallel signal is output to the transmitter 220. For example, the multi-lane transmission unit 143-i uses four 28G electric wires in parallel to perform OTLCn. The parallel signal of the n # i frame is output to the transmitter 220. Each transmitter 220 uses optical subcarriers having different optical frequencies. The transmitter 220 converts the received parallel signal from an electrical signal to an optical signal and performs multicarrier transmission. A plurality of multilane transmission units 143-i may be connected to one transmitter 220. When j (j is 2 or more and n or less) multi-lane transmission units 143-i are connected to one transmitter 220, the transmitter 220 transmits j parallel signals using j × 100G optical subcarriers. To transmit.

  The reception processing unit 150 includes a line side reception processing unit 160, a separation processing unit 170, and a client signal transmission unit 180.

The line side reception processing unit 160 includes multilane reception units 161-1 to 161-n, OH processing units 162-1 to 162-n, and a deinterleaving unit 163.
The multilane receiving units 161-1 to 161-n receive optical signals received by the receiver 230 through multicarrier transmission as electrical signals. The receiver 230 receives an optical signal using optical subcarriers having different optical frequencies. The multilane receiving unit 161-i outputs, for example, an electrical signal received in parallel from the receiver 230 using four 28G electrical wirings to the OH processing unit 162-i.

The OH processing units 162-1 to 162-n receive OTLCn. The head of the frame is recognized based on FAS (frame alignment signal) or MFAS (multiframe alignment signal) set in the OH of n frames. The OH processing unit 162-i detects the head position, compensates for the delay time difference, and detects the OTLCn. The n # i frame is extracted and output to the deinterleave unit 163.
The deinterleaving unit 163 receives the OTLCn.1 received from the OH processing units 162-1 to 162-n. n # 1 frame to OTLC n. n # n frames are deinterleaved to generate one OTUCn frame.

The separation processing unit 170 includes a deframing unit 171 and a demultiplexing unit 172.
The deframing unit 171 performs FEC decoding on the signal of the OTUCn frame generated by the deinterleaving unit 163, extracts an ODUCn frame in which the LO ODU frame is time-multiplexed from the decoded OTUCn frame, and outputs the ODUCn frame to the demultiplexing unit 172.
The demultiplexing unit 172 extracts the LO ODU frame in which each client signal is set from the ODUCn frame signal extracted by the deframing unit 171, and outputs the electric path signal of the LO ODU frame to the ODU-SW 210.

The client signal transmission unit 180 includes an OH processing unit 181, a demapping unit 182, and a transmission unit 183.
The OH processing unit 181 receives the electrical path signal from the ODU-SW 210, and decodes the LO ODU frame from the received electrical path signal. The OH processing unit 181 performs processing related to OH on the LO ODU frame and outputs it to the demapping unit 182.
The demapping unit 182 receives the electrical path signal of the LO ODU frame from the OH processing unit 181, extracts a client signal from the received electrical path signal, and outputs the client signal to the transmission unit 183.
The transmission unit 183 transmits the client signal extracted by the demapping unit 182.

  The client signal receiving unit 120 and the multiplex processing unit 130, and the separation processing unit 170 and the client signal transmitting unit 180 may be connected without going through the ODU-SW 210.

FIG. 2 is a diagram illustrating a frame structure of OTUCn.
OTUCn is generated by adding FACn OH, OTUCn OH, OPUCn OH, and OTUCn FEC to ODUCn. OTUCn is marked with 4 rows and 4080 × n columns.
A client signal is mapped to the OPUCn payload (Payload) in the (16 × n + 1) to 3824 × n columns of OTUCn. OH is set in the 1st to 16xn columns of the OTUCn frame. FACn OH is set in the 1st to 7 × n columns of the first row. The FACn OH includes information necessary for frame synchronization. In the (7 × n + 1) to 14 × n columns, OTUCn OH accommodating the section monitoring information of the optical channel is inserted. ODUCn OH is inserted in the 1st to 14xn columns of the 2nd to 4th rows, and accommodates optical channel path management operation information. In the (14 × n + 1) to 16 × n columns, OPUCn OH is inserted, and information necessary for mapping / demapping of client signals is accommodated. A parity check byte for FEC is added to the OPUCn FEC in the 3824 × n + 1 to 4080 × n columns.

FIG. 3 shows OTLCn. It is a figure which shows the frame structure of n.
OTLCn. n is represented by 4 rows and 4080 columns. OTLCn. n # 1-OTLC n. n # n is obtained by dividing the OTUCn frame by byte interleaving.
The OTUCn payload of OTUCn is OTLCn. n # i of OPUCn. Maps to n # i payload.
OTLCn. OH is set in the 1st to 16th columns of n # i. OTLCn. The OH of n # i is set based on OTUCn OH or the like. In the 1st to 7th columns of the first row, FALCn. n # i OH is set. FALCn. The n # i OH includes information necessary for frame synchronization, such as FAS and MFAS. In the 8th to 14th columns, OTLCn. n # i OH is inserted. In the 1st to 14th nth columns of the 2nd to 4th rows, ODLCn. n # i OH is inserted to accommodate optical channel path management operation information. In columns 15-16, OPLCn. n # i OH is inserted, and information necessary for mapping / demapping of client signals is accommodated. A parity check byte for FEC is added to the OTUC # i FEC in the 3825th to 4080th columns.

FIG. 4 is a diagram illustrating an optical channel used for transmission of an optical signal.
FIG. 4A is a diagram illustrating an optical channel when a 400G optical signal is serially transmitted at one optical frequency (single carrier), and FIG. 4B is a diagram illustrating an optical signal of 400G with four optical subcarriers. It is a figure which shows the optical channel in the case of carrying out parallel transmission (multicarrier transmission) according to FIG.
In the conventional electronic circuit, it is difficult to continue to extend the band that can be serially transmitted with one optical frequency beyond 100 G, as shown in FIG. Therefore, in OTUCn, broadband transmission is realized without being restricted by electronic circuits by performing parallel transmission of a band exceeding 100 G using a plurality of optical subcarriers. For this parallel transmission, polarization multiplexing, multilevel modulation, or the like is used. The optical subcarrier band varies depending on the modulation method.
FIG. 4B shows an example in which one 400 G optical channel is transmitted in parallel by 100 G four optical subcarriers. FIG. 4C shows one 400 G optical channel through 200 G two optical subcarriers. This is an example when parallel transmission is performed. Further, by changing n, as shown in FIG. 4D, the transmission band can be increased in units of 100G.

FIG. 5 is a diagram illustrating a configuration example of the optical transmission device 50 according to an embodiment of the present invention.
The optical transmission device 50 includes an ODU cross-connect function unit 51, an optical transmission function unit 55, and a monitoring control unit 60.
In the ODU cross-connect function unit 51, one or more UNI (user-network interface) cards 52 and one or more NNI (network-network interface) cards 54 are connected by an ODU-XC (cross-connect) 53. The UNI card 52 is connected to a communication device on the client side according to each communication standard. The OTN framer 521 of the UNI card 52 has the functions of the client signal reception unit 120 and the client signal transmission unit 180 of the OTN framer 800 shown in FIG. The ODU-XC 53 corresponds to the ODU-SW 210 shown in FIG. The NNI card 54 includes an OTN framer 541 and a plurality of optical SC (subcarrier) transceivers 542. The OTN framer 541 has the functions of the multiplex processing unit 130, the line side transmission processing unit 140, the line side reception processing unit 160, and the separation processing unit 170 of the OTN framer 800 shown in FIG. The optical SC transceiver 542 has the functions of the transmitter 220 and the receiver 230 shown in FIG. The optical SC transceiver 542 includes, for example, a DSP (Digital Signal Processor). Each optical SC transceiver 542 outputs an optical signal through one port.

The optical transmission function unit 55 includes a transponder 56, a multiplexer / demultiplexer 57, a wavelength XC (cross connect) 58, and an optical AMP (amplifier) 59.
The transponder 56 includes an OTN framer 561 and a plurality of optical SC transceivers 562. The OTN framer 561 has the function of the OTN framer 800 shown in FIG. 1, and the optical SC transceiver 562 has the functions of the transmitter 220 and the receiver 230 shown in FIG. The optical SC transceiver 562 is configured with a DSP, for example. Each optical SC transceiver 562 outputs an optical signal through one port.

  In a normal operation state in which no optical SC transceiver 542 or optical SC transceiver 562 has failed, each NNI card 54 and each transponder 56 use optical channels having different optical frequencies. The NNI card 54 having four optical SC transceivers 542 and the transponder 56 having four optical SC transceivers 542 transmit an optical signal of one optical channel using four optical subcarriers. The NNI card 54 having two optical SC transceivers 542 and the transponder 56 having two optical SC transceivers 562 transmit optical signals of one optical channel by two optical subcarriers. The optical transmission device 50 may be configured not to include either the ODU cross-connect function unit 51 or the transponder 56.

The multiplexer / demultiplexer 57 is a wavelength multiplexing function unit having a colorless function, and performs colorless WDM (Wavelength Division Multiplexing) of an optical signal. As the multiplexer / demultiplexer 57, for example, an optical coupler, an LCoS-WSS (Liquid Crystal on Silicon-Wavelength Selective Switch), a MEMS-WSS (Micro Electro Mechanical Systems-Wavelength Selective Switch), or the like is used. The plurality of ports provided in the multiplexer / demultiplexer 57 are respectively connected to the ports of the optical SC transceivers 542 of the NNI card 54 and the ports of the optical SC transceivers 562 of the transponder 56. With the colorless function, the relationship between the port and the wavelength is not fixed but variable. The multiplexer / demultiplexer 57 multiplexes the optical signals received from each optical SC transceiver 542 of each NNI card 54 and each optical SC transceiver 562 of each transponder 56 and transmits it to the other optical transmission device 50 on the receiving side. To do. The multiplexer / demultiplexer 57 demultiplexes the optical signal received from the other optical transmission device 50 on the transmission side, and each optical SC transceiver 542 of each NNI card 54 and each optical SC transceiver 562 of each transponder 56. Output to.
The wavelength XC 58 inserts the path of the optical signal received from the multiplexer / demultiplexer 57 and outputs it to the setting route. The wavelength XC 58 branches the path of the optical signal received from the optical AMP 59 and outputs it to the multiplexer / demultiplexer 57.
The optical AMP 59 amplifies the optical signal.

The monitoring control unit 60 monitors and controls each unit. The monitoring control unit 60 includes a device management information storage unit 61, a failure detection unit 62, and a wavelength switching unit 63.
The device management information storage unit 61 stores device management information. The device management information indicates configuration information, operating status information of each optical SC transceiver 542 and each optical SC transceiver 562, and subcarrier information. The configuration information indicates whether the optical SC transceiver 542 provided in each NNI card 54, the optical SC transceiver 562 provided in each transponder 56, each optical SC transceiver 542, and each optical SC transceiver 562 is a common spare. Information. The operating state information indicates whether each optical SC transceiver 542 and each optical SC transceiver 562 is in an operating state during normal operation, switching operation, stoppage, or failure. The subcarrier information indicates optical subcarrier identification information used by each optical SC transceiver 542 and each optical SC transceiver 562. For example, information indicating the wavelength of the optical subcarrier may be used as the identification information of the optical subcarrier, or a number identifying the optical subcarrier may be used.

  The failure detection unit 62 monitors the reception state of the optical subcarrier. The failure detection unit 62 notifies the optical transmission device 50 on the transmission side of information on the optical subcarrier in which the failure is detected. Further, when receiving information on the optical subcarrier in which the failure is detected from the optical transmission device 50 on the receiving side, the failure detection unit 62 refers to the device management information and uses the optical subcarrier in which the failure has occurred. The transceiver 542 or the optical SC transceiver 562 is specified. The failure detection unit 62 determines that a failure has occurred in the specified SC transceiver 542 or optical SC transceiver 562. The failure detection unit 62 may monitor the optical SC transmitter / receiver 542 and the optical SC transmitter / receiver 562 in its own device to detect a failure. The failure detection unit 62 refers to the device management information and selects the optical SC transmitter / receiver 542 or the optical SC transmitter / receiver 562 to be switched from the shared standby optical SC transmitter / receiver 542 or the optical SC transmitter / receiver 562. The failure detection unit 62 detects the failure of the optical SC in which a failure has occurred in the OTN framer 541 of the NNI card 54 having the failed optical SC transceiver 542 or the OTN framer 561 of the transponder 56 having the failed optical SC transceiver 562. Information on the transceiver 542 or the optical SC transceiver 562 and information on the switching destination optical SC transceiver 542 or the optical SC transceiver 562 are notified. The failure detection unit 62 sets the operating state of the SC transmitter / receiver 542 or the optical SC transmitter / receiver 562 in which the failure has occurred to failure, and sets the operating state of the switching destination SC transmitter / receiver 542 or optical SC transmitter / receiver 562 to switching operation. Rewrite the operating status information.

  The wavelength switching unit 63 uses the wavelength used by the optical SC transmitter / receiver 542 or the optical SC transmitter / receiver 562 in which the failure has occurred in the switching-destination optical SC transmitter / receiver 542 or the switching-destination optical SC transmitter / receiver 562. Instruct.

  FIG. 6 is a diagram illustrating an example of mapping a path to an ODUCn frame (signal frame) in a normal operation state. In the figure, n = 4 and the NNI card 54 includes four optical SC transceivers 542. The NNI card 54 that does not include the shared spare optical SC transceiver 542 is referred to as an NNI card 54a, and the NNI card 54 that includes the shared spare optical SC transceiver 542 is referred to as an NNI card 54b. The OTN framer 541 included in the NNI card 54a is referred to as an OTN framer 541a, and the i-th optical SC transceiver 542 included in the NNI card 54a is referred to as an optical SC transceiver 542a-i. Further, the OTN framer 541 provided in the NNI card 54b is referred to as an OTN framer 541b, and the i-th optical SC transceiver 542 provided in the NNI card 54b is referred to as an optical SC transceiver 542b-i. The optical SC transceiver 542b-1 is a shared spare optical SC transceiver. In a normal operation state in which no failure of the optical SC transceiver 542 occurs, the optical SC transceiver 542a-i uses a 100G optical subcarrier of wavelength λai in the optical channel ch1, and the optical SC transceiver 542b-i The 100 G optical subcarrier of wavelength λbi in the optical channel ch2 is used.

  The path mapped to the ODUC4 frame is a logical path assigned to the client signal, and corresponds to one LO ODU or one ODTU frame. The 1.25G TS in the ODUC4 frame is statically or dynamically determined in advance as to which of OTLC4.4 # 1 to OTLC4.4 # 4 is mapped. In the figure, the TS in the first row of the ODUC4 frame is OTLC 4.4 # 1, the TS in the second row is OTLC 4.4 # 2, and the TS in the third row is OTLC 4.4 # 3. The case where TS is mapped by OTLC4.4 # 4 is shown. In the figure, for simplicity, TS for 100G of OTLC 4.4 # i is represented by 10 TSs in one row. In the following, OTLCn. The TS group of the ODUCn frame mapped to n # i is referred to as OTLCn. It is described as an n # i region. OTLCn. The n # i parallel signal is transmitted from the i-th optical SC transceiver 542. That is, in the ODUC4 frame Fa that is an ODUC4 frame Fa used by the OTN framer 541a, the area of OTLC4.4 # i corresponds to the optical SC transceiver 542a-i, and in the ODUC4 frame Fb that is an ODUC4 frame used by the OTN framer 541b. .4 # i corresponds to the optical SC transceiver 542b-i.

  In the figure, in the ODUC4 frame Fa, the 10G path of the client A is allocated to the OTLC 4.4 # 4 area, the 100G path of the client B is allocated to the OTLC 4.4 # 1 area, and the 200G of the client C Paths are assigned to the OTLC 4.4 # 2 and # 3 areas. In the ODUC4 frame Fb, the 100G path of the client D is assigned to the OTLC 4.4 # 2 area, and the 200G path of the client E is assigned to the OTLC 4.4 # 3 and # 4 areas. No path is assigned to the OTLC 4.4 # 1 area corresponding to the shared spare optical SC transceiver 542b-1 of the ODUC4 frame Fb.

  The optical SC transceivers 542a-1 to 542a-4 of the OTN framer 541a use the optical subcarriers with wavelengths λa1 to λa4 to convert the parallel signals in which the client signals of the clients A, B, and C are set in the band of the optical channel ch1. Multi-carrier transmission. The optical SC transceivers 542b-1 to 542b-4 of the OTN framer 541b multi-carrier transmit parallel signals in which the client signals of the clients D and E are set by the optical subcarriers of the wavelengths λb1 to λb4 in the band of the optical channel ch2. To do. However, the client signal is not set in the parallel signal of OTLC 4.4 # 1 transmitted from the shared standby SC transceiver 542b-1. Note that the SC transceiver 542b-1 is stopped in the normal operation state and does not have to transmit the optical subcarrier.

  FIG. 7 is a diagram illustrating an example of mapping a path to an ODUCn frame when an optical SC transceiver is faulty. This figure shows a case where the optical SC transceiver 542a-3 of the NNI card 54a shown in FIG. 6 has failed. The OTN framer 541a sets the path assignment destination assigned to the TS in the area corresponding to the optical SC transceiver 542a-3 of the ODUC4 frame Fa, as the switching destination optical SC transceiver 542b of the ODUC4 frame Fb used by the OTN framer 541b. Change to the TS of the area corresponding to -1. In other words, the OTN framer 541a determines the portion of the TS of the ODUC4 frame Fa to which the path of the client C is assigned that is assigned to the TS of the OTLC4.4 # 3 area as the OTLC4.4 of the ODUC4 frame Fb. Change the TS of area # 1 to be the allocation destination. Further, the optical SC transceiver 542b-1 of the NNI card 54b changes the wavelength of the optical subcarrier to be used to λa3 used by the failed optical SC transceiver 542a-3.

  Thereby, the optical SC transceivers 542a-1, 542a-2 and 542a-4 of the OTN framer 541a and the optical SC transceiver 542b-1 of the OTN framer 541b have the wavelengths λa1 to λa4 in the band of the optical channel ch1. Multi-carrier transmission is performed on parallel signals in which client signals of clients A, B, and C are set by optical subcarriers. On the other hand, the optical SC transceivers 542b-2 to 542b-4 of the OTN framer 541b multiplex the parallel signals in which the client signals of the clients D and E are set by the optical subcarriers of the wavelengths λb2 to λb4 in the band of the optical channel ch2. Carrier transmission. Since the optical transmission device 50 on the receiving side can receive the parallel signal transmitted by the multi-carrier transmission using the optical subcarriers having the wavelengths λa1 to λa4 by one NNI card 54 or one transponder 56 corresponding to the optical channel ch1, The reception process is performed in the same manner as in the normal operation state.

If a plurality of optical SC transceivers fail, a plurality of shared spare optical SC transceivers may be used.
FIG. 8 is a diagram illustrating an example of mapping a path to an ODUCn frame when a multiple optical SC transceiver is faulty. In this figure, when the optical SC transceiver 542 of the NNI card 54a further fails in the state shown in FIG. 7, in addition to the NNI card 54b, the NNI which is another NNI card 54 including the shared spare optical SC transceiver 542. The case where the card 54c is used is shown. The OTN framer 541 included in the NNI card 54c is referred to as an OTN framer 541c, and the i-th optical SC transceiver 542 included in the NNI card 54c is referred to as an optical SC transceiver 542c-i. In the normal operation state, the optical SC transceiver 542c-i uses a 100G optical subcarrier having the wavelength λci in the optical channel ch3. In the ODUC4 frame Fc that is the ODUC4 frame used by the OTN framer 541c, the 100G path of the client F is allocated to the OTLC 4.4 # 1 area, and the 200G path of the client G is the OTLC 4.4 # 2 and # 3 area Assigned. No path is allocated to the area of OTLC4.4 # 4 corresponding to the shared spare optical SC transceiver 542c-4 of the ODUC4 frame Fc.

In the state of FIG. 7, it is assumed that the optical SC transceiver 542a-1 of the NNI card 54a has failed. The OTN framer 541a sets the path assignment destination assigned to the TS in the area corresponding to the optical SC transceiver 542a-1 of the ODUC4 frame Fa to the switching destination optical SC transceiver 542c of the ODUC4 frame Fc used by the OTN framer 541c. -4 in the area corresponding to -4. That is, the OTN framer 541a changes the path assignment destination of the client B from the TS in the OTLC4.4 # 1 area of the ODUC4 frame Fa to the TS in the OTLC4.4 # 4 area of the ODUC4 frame Fc. The optical SC transceiver 542c-4 of the NNI card 54c changes the wavelength of the optical subcarrier to be used to λa1 used by the failed optical SC transceiver 542a-1. Thus, the optical SC transceivers 542a-2 and 542a-4 of the OTN framer 541a, the optical SC transceiver 542b-1 of the OTN framer 541b, and the optical SC transceiver 542c-4 of the OTN framer 541c are connected to the optical channel ch1. In the band, multi-carrier transmission of parallel signals in which client signals of clients A, B, and C are set by optical subcarriers of wavelengths λa1 to λa4. On the other hand, in the optical SC transceivers 542b-2 to 542b-4 of the OTN framer 541b, the client signals of the clients D and E are set by the optical subcarriers of the wavelengths λb2 to λb4 in the band of the optical channel ch2, as in FIG. The parallel signal thus transmitted is transmitted by multicarrier. The optical SC transceivers 542c-1 to 542c-3 of the OTN framer 541c perform multicarrier transmission of parallel signals in which the client signals of the clients F and G are set by the optical subcarriers of the wavelengths λc1 to λc3 in the band of the optical channel ch3. To do.
One NNI card 54 may include a plurality of shared spare optical SC transceivers 542.

  FIG. 9 is a diagram illustrating an example of mapping a path to an ODUCn frame in a normal operation state when a plurality of parallel signals are transmitted using one optical subcarrier. The NNI card 54 that transmits a plurality of parallel signals using one optical subcarrier includes k optical SC transceivers 542 (k is an integer less than n). In the figure, a case where n = 4 and k = 2 is shown. The NNI card 54 that does not include the shared spare optical SC transceiver 542 is referred to as an NNI card 54d, and the NNI card 54 that includes the shared spare optical SC transceiver 542 is referred to as an NNI card 54e. The OTN framer 541 provided in the NNI card 54d is referred to as an OTN framer 541d, and the j-th (j is an integer not less than 1 and not more than k) optical SC transceiver 542 provided in the NNI card 54d is referred to as an optical SC transceiver 542d-j. Describe. Further, the OTN framer 541 provided in the NNI card 54e is described as an OTN framer 541e, and the j-th optical SC transmitter / receiver 542 provided in the NNI card 54e is described as an optical SC transmitter / receiver 542e-j. The optical SC transceiver 542e-1 is a shared spare optical SC transceiver. In the normal operation state, the optical SC transceiver 542d-j uses a 200G optical subcarrier with the wavelength λdj in the optical channel ch1, and the optical SC transceiver 542e-j has a 200G optical subcarrier with the wavelength λej in the optical channel ch2. Use a carrier.

  The TS in the first row of the ODUC4 frame is OTLC4.4 # 1, the TS in the second row is OTLC4.4 # 2, the TS in the third row is OTLC4.4 # 3, and the TS in the fourth row is OTLC4. 4 # 4 is mapped. The parallel signals OTLC 4.4 # 1 and # 2 are transmitted from the first optical SC transceiver 542, and the parallel signals OTLC 4.4 # 3 and # 4 are transmitted from the second optical SC transceiver 542. That is, in the ODUC4 frame Fd that is the ODUC4 frame used by the OTN framer 541d, the areas of OTLC4.4 # 1 and # 2 correspond to the optical SC transceiver 542d-1, and the areas of OTLC4.4 # 3 and # 4 are This corresponds to the optical SC transceiver 542d-2. In the ODUC4 frame Fe, which is the ODUC4 frame used by the OTN framer 541e, the OTLC 4.4 # 1 and # 2 areas correspond to the optical SC transceiver 542e-1, and the OTLC 4.4 # 3 and # 4 areas correspond to the optical SC. This corresponds to the transceiver 542e-2.

  In the ODUC4 frame Fd, the 10G path of client A is assigned to the OTLC 4.4 # 4 area, the 100G path of client B is assigned to the OTLC 4.4 # 1 area, and the 200G path of client C is assigned to the OTLC4. 4 # 2 and # 3 are allocated. Further, in the ODUC4 frame Fe, the 200G path of the client E is assigned to the OTLC 4.4 # 3 and # 4 areas. No path is assigned to the areas of OTLC 4.4 # 1 and # 2 corresponding to the shared spare optical SC transceiver 542e-1.

  The optical SC transceivers 542d-1 and 542d-2 of the OTN framer 541d use the optical subcarriers of wavelengths λd1 and λd2 to convert the parallel signals in which the client signals of the clients A, B, and C are set in the band of the optical channel ch1, respectively. Multi-carrier transmission. Each of the optical SC transceivers 542e-1 and 542e-2 of the OTN framer 541e performs multicarrier transmission of the parallel signal in which the client signal of the client E is set by the optical subcarriers of the wavelengths λe1 and λe2 in the band of the optical channel ch2. . However, the client signal is not set in the parallel signals of OTLC 4.4 # 1 and # 2 transmitted by the shared standby SC transceiver 542e-1. Note that the SC transceiver 542e-1 is stopped in the normal operation state and does not have to transmit an optical subcarrier.

  FIG. 10 is a diagram illustrating an example of mapping a path to an ODUCn frame when an optical SC transceiver fails when a plurality of parallel signals are transmitted using one optical subcarrier. This figure shows a case where the optical SC transceiver 542d-2 of the NNI card 54d shown in FIG. 9 has failed. The OTN framer 541d assigns the path assignment destination assigned to the TS in the area corresponding to the optical SC transceiver 542d-2 of the ODUC4 frame Fd to the switching destination optical SC transceiver 542e-1 of the ODUC4 frame Fe of the OTN framer 541e. To the TS of the area corresponding to. In the case of the figure, the OTN framer 541d determines the portion of the TS of the ODUC4 frame Fd to which the path of the client C is assigned as the TS of the OTLC4.4 # 3 area in the ODUC4 frame Fe. Change to the area of OTLC 4.4 # 1. Further, the OTN framer 541d changes the assignment destination of the path of the client A assigned to the TS of the OTLC4.4 # 4 area of the ODUC4 frame Fd to the TS of the OTLC4.4 # 2 area of the ODUC4 frame Fe. . Further, the optical SC transceiver 542e-1 of the NNI card 54e changes the wavelength of the optical subcarrier to be used to λd2 used by the failed optical SC transceiver 542d-2.

  As a result, the optical SC transceiver 542d-1 of the OTN framer 541d and the optical SC transceiver 542e-1 of the OTN framer 541e are connected to the clients A, B, and C by the optical subcarriers of the wavelengths λd1 and λd2 in the band of the optical channel ch1. Multi-carrier transmission of a parallel signal in which the client signal is set. On the other hand, the optical SC transceiver 542e-2 of the OTN framer 541e transmits a parallel signal in which the client signal of the client E is set by the optical subcarrier of the wavelength λe2 in the band of the optical channel ch2.

  Although the case of the NNI card 54 has been described above, the same applies to the case of the transponder 56.

In the normal operation state, each NNI card and each transponder use optical channels having different optical frequencies (wavelengths). When a plurality of optical subcarriers are wavelength-multiplexed in one NNI card or one transponder and output from one port to the multiplexer / demultiplexer, if the wavelengths of some of the optical subcarriers are changed, The signal is interrupted in the waver. Therefore, an arbitrary wavelength cannot be set for each optical subcarrier. However, when one OTUCn signal is transmitted through different optical channels across a plurality of NNI cards or transponders without changing the wavelength of the optical subcarrier, it is necessary to absorb the delay difference between the different optical channels. Therefore, a large delay adjustment function must be added to the optical transmission device for each optical subcarrier.
In this embodiment, the NNI card 54 and the transponder 56 output each optical subcarrier from a different port, and each output optical subcarrier is multiplexed in the multiplexer / demultiplexer 57 in which the colorless function is implemented. . Therefore, the optical transmission device 50 is used by the shared standby transceiver 542 of the NNI card 54 or the optical SC transceiver 562 of the transponder 56 when any one of the optical SC transceivers 542 or the optical SC transceiver 562 fails. By changing the wavelength of the optical subcarrier to be used to the wavelength used by the optical SC transmitter / receiver 542 or the optical SC transmitter / receiver 562 in which a failure has occurred, one optical signal is transmitted across a plurality of NNI cards 54 or a plurality of transponders 56. An OTUCn signal can be transmitted. As a result, protection with a high degree of spare sharing can be realized for the optical subcarrier.

  FIG. 11 is a diagram illustrating functional blocks related to transmission of the NNI card 54 included in the optical transmission device 50. The two NNI cards 54 are the NNI card 54a (first optical signal transmission unit) and the NNI card 54b (second optical signal transmission unit) shown in FIGS. The NNI card 54c shown in FIG. 8 has the same configuration as the NNI card 54b. In this figure, the same parts as those of the framer 800 shown in FIG. 1 and the optical transmission device 50 shown in FIG. In the figure, a case where n = 4 is shown as an example.

  The NNI card 54a includes an OTN framer 541a and optical SC transceivers 542a-1 to 542a-n. In the case of the NNI card 54d shown in FIG. 9, the NNI card 54a includes k optical SC transceivers 542. The OTN framer 541a includes a multiplex processing unit 130a (first multiplex processing unit) and a line side transmission processing unit 140 (first parallel signal generation unit). The multiprocessing unit 130a includes a multiplexing unit 131a and a framing unit 132. The multiplexing unit 131a has the same function as the multiplexing unit 131 shown in FIG. Furthermore, the multiplexing unit 131a corresponds to the path assigned to the ODUCn frame area corresponding to the optical SC transceiver 542a-i where the failure has occurred, to the optical SC transceiver 542b-i that is the switching destination of the NNI card 54b. Assigned to the area of the ODUCn frame. The optical SC transceivers 542a-1 to 542a-n include a transmitter 220.

  The NNI card 54b includes an OTN framer 541b and optical SC transceivers 542b-1 to 542b-n. In the case of the NNI card 54e shown in FIG. 9, the NNI card 54b includes k optical SC transceivers 542. The OTN framer 541b includes a multiplex processing unit 130b (second multiplex processing unit) and a line side transmission processing unit 140 (second parallel signal generation unit). The multiprocessing unit 130b includes a multiplexing unit 131b and a framing unit 132. The multiplexing unit 131b has the same function as the multiplexing unit 131 shown in FIG. Further, the multiplexing unit 131b transfers the path assigned to the area of the ODUCn frame corresponding to the optical SC transceiver 542a-i in which the failure has occurred in the OTN framer 541a to the optical SC transceiver 542b to which the NNI card 54b is switched. -Assign to the area of the ODUCn frame corresponding to i. The multiplexing unit 131b receives from the OTN framer 541a the signal of the path assigned to the area of the ODUCn frame corresponding to the failed optical SC transceiver 542a-i, and switches to the switching destination optical SC transceiver 542b-i. Is set in the ODUCn frame area corresponding to. The optical SC transceivers 542b-1 to 542b-n include a transmitter 220.

  FIG. 12 is a diagram illustrating functional blocks related to transmission of the transponder 56 included in the optical transmission device 50. In this figure, the same parts as those of the framer 800 shown in FIG. 1, the optical transmission device 50 shown in FIG. 5, and the optical transmission device 50 shown in FIG. In the figure, a case where n = 4 is shown as an example. The transponder 56 that does not include the shared spare optical SC transceiver 562 is referred to as a transponder 56a, and the transponder 56 that includes the shared spare optical SC transceiver 562 is referred to as a transponder 56b. The optical SC transceiver 562 includes a transmitter 220. The OTN framer 561a of the transponder 56a includes a client signal receiving unit 120, a multiprocessing unit 130a, and a line side transmission processing unit 140. The OTN framer 561b of the transponder 56b includes a client signal receiving unit 120, a multiprocessing unit 130b, and a line side transmission processing unit 140.

  When the modulation scheme of the optical SC transceiver 542 and the optical SC transceiver 564 is variable, the optical subcarrier band varies depending on the modulation scheme. For example, in the case of QPSK modulation, one optical subcarrier is 100G, in the case of 8QAM modulation, one optical subcarrier is 150G, and in the case of 16QAM modulation, one optical subcarrier is 200G. For this reason, n optical SC transceivers 542 and optical SC transceivers 564 are physically provided, and k optical SC transceivers 542 and optical SC transceivers 564 are provided by changing their modulation schemes. It can be operated.

FIG. 13 is a processing flow in the optical transmission device 50 on the transmission side when an optical SC transceiver fails. Hereinafter, a case where the optical SC transceiver 542a-i fails in the NNI card 54a will be described as an example.
In the optical transmission device 50 on the reception side, the failure detection unit 62 detects a failure of the received optical subcarrier. The failure detection unit 62 of the optical transmission device 50 on the reception side notifies the optical transmission device 50 on the transmission side of information on the optical subcarrier where the failure has occurred. For the notification, a control signal transmission / reception network may be used, or an OH empty area of a parallel signal transmitted from the reception-side optical transmission apparatus 50 to the transmission-side optical transmission apparatus 50 may be used. The failure detection unit 62 of the transmission-side optical transmission device 50 receives information on the optical subcarrier where the failure has occurred from the reception-side optical transmission device 50. The failure detection unit 62 refers to the subcarrier information in the device management information stored in the device management information storage unit 61, and identifies the SC transceiver 542 that uses the notified optical subcarrier. The failure detection unit 62 detects a failure of the specified optical SC transceiver 542 (step S10). Assume that the SC transceiver 542 in which a failure is detected is the optical SC transceiver 542a-3. The failure detection unit 62 updates the operating state of the optical SC transceiver 542a-3 set in the operating state information in the device management information during a failure.

  The failure detection unit 62 refers to the device management information stored in the device management information storage unit 61, and selects a switching-destination optical SC transceiver (step S15). Specifically, the failure detection unit 62 is an optical SC transmitter / receiver 542 whose configuration information is set to be a shared spare, and whose operation status information is set to normal operating or stopped. One SC transceiver 542 is selected. It is assumed that the selected switching-destination optical SC transceiver is the optical SC transceiver 542b-1 of the NNI card 54b. The failure detection unit 62 updates the operating state of the optical SC transceiver 542b-1 set in the operating state information in the device management information during switching operation.

  The failure detection unit 62 notifies the OTN framer 541a of the NNI card 54a that the optical SC transceiver 542a-3 has failed and that the optical SC transceiver 542b-1 of the NNI card 54b is the switching destination (step S20). . Further, the failure detection unit 62 may notify the OTN framer 541b of the NNI card 54b that the optical SC transceiver 542b-1 is the switching destination. The wavelength switching unit 63 reads the wavelength λa3 used by the optical SC transmitter / receiver 542a-3 in which the failure has occurred from the subcarrier information in the device management information. The wavelength switching unit 63 instructs the switching-destination optical SC transceiver 542b-1 included in the NNI card 54b to set the wavelength of the optical subcarrier to be used to λa3 (step S25). The optical SC transceiver 542b-1 changes the wavelength of the optical subcarrier from λb1 to λa3. The wavelength switching unit 63 instructs to use the wavelength λa3 after starting the optical SC transceiver 542b-1 when the switching destination optical SC transceiver 542b-1 is stopped.

  The multiplexing unit 131a in the OTN framer 541a of the NNI card 54a includes the area of OTLC 4.4 # 3 corresponding to the optical SC transceiver 542a-3 notified of the failure, and is mapped to the TS of the ODUC4 frame. Identify the path. The OTN framer 541a determines the portion of the TS of the ODUC4 frame Fa to which the path of the client C is assigned that is assigned to the TS in the area of the OTLC 4.4 # 3 as the switching destination optical SC transceiver 542b- It changes so that TS of the area | region corresponding to 1 may be made an allocation destination (step S30). Further, the multiplexing unit 131b of the OTN framer 541b receives a notification from the multiplexing unit 131a of the OTN framer 541-s1, and the path assignment destination of the client C corresponds to the switching-destination optical SC transceiver 542b-1. Change to assign to the TS in the area. The area corresponding to the optical SC transceiver 542b-1 is the OTLC 4.4 # 1 area of the ODUC4 frame Fb used by the OTN framer 541b. By changing the TS allocation, the accommodated traffic of the failed optical SC transceiver 542a-3 is switched to the switching destination optical SC transceiver 542b-1.

  After the TS allocation is changed, the multiplexing unit 131a of the NNI card 54a transmits the 10G client signal of the client A to the OTLC 4.4 # 4 area of the ODUC4 frame Fa used by the multiplexing processing unit 130a, and the 100G client of the client B The signal is mapped to the OTLC 4.4 # 1 area of the ODUC4 frame Fa. Further, the multiplexing unit 131a transmits 100G of the 200G client signal of the client C to the OTLC4.4 # 2 area of the ODUC4 frame Fa, and the remaining 100G of the OTUC4 of the ODUC4 frame Fb used by the multiplexing processing unit 130b. Mapping to the 4 # 1 area. Further, the multiplexing unit 131b of the NNI card 54b sends the 100G client signal of the client D to the OTLC4.4 # 2 area of the ODUC4 frame Fb, and the 200G client signal of the client E to the OTLC4.4 # 3 of the ODUC4 frame Fb. And map to the area of # 4.

The framing unit 132 of the NNI card 54a generates an OTUC4 frame by adding OH and FEC to the ODUC4 frame Fa in which the multiprocessing unit 130a sets the client signal. The line side transmission processing unit 140 of the NNI card 54a outputs the OTLC 4.4 # 1 parallel signal in which the client signal of the client B is set to the optical SC transceiver 542a-1, and a part of the client signal of the client C is received. The set OTLC 4.4 # 2 parallel signal is output to the optical SC transceiver 542a-2, and the client OTLC 4.4 # 4 parallel signal to which the client A client is set is output to the optical SC transceiver 542a-4. To do.
On the other hand, the framing unit 132 of the NNI card 54b generates an OTUC4 frame by adding OH and FEC to the ODUC4 frame Fb in which the multiprocessing unit 130b sets the client signal. The line-side transmission processing unit 140 of the NNI card 54b outputs the OTLC 4.4 # 1 parallel signal in which the remaining client signals of the client C are set to the optical SC transceiver 542b-1, and the client signal of the client D is set. The output OTLC 4.4 # 2 parallel signal is output to the optical SC transmitter / receiver 542b-2, and the OTLC 4.4 # 3 parallel signal in which a part of the client signal of the client E is set is output to the optical SC transmitter / receiver 542b-3. And the OTLC 4.4 # 4 parallel signal in which the remaining client signal of the client E is set is output to the optical SC transceiver 542b-4.
As described above, the optical SC transceivers 542a-1, 542a-2, and 542a-4 of the OTN framer 541a and the optical SC transceiver 542b-1 of the OTN framer 541b have wavelengths λa1 to λa4 in the band of the optical channel ch1. The parallel signals in which the client signals of the clients A, B, and C are set are transmitted by the optical subcarriers. Then, the optical SC transceivers 542b-2 to 542b-4 of the OTN framer 541b multiplex the parallel signals in which the client signals of the clients D and E are set by the optical subcarriers of the wavelengths λb2 to λb4 in the band of the optical channel ch2. Carrier transmission.

  In the NNI card 54 having the shared spare optical SC transceiver 542, when an optical SC transceiver 542 other than the shared spare fails, the shared spare optical SC transceiver 542 provided in the NNI card 54 is used as a switching destination. May be used. For example, when a failure occurs in the optical SC transceiver 542b-2 of the NNI card 54b from the normal operation state, the wavelength switching unit 63 instructs the optical SC transceiver 542b-1 to use the wavelength λb2. The multiplexing unit 131b in the OTN framer 541b identifies the path of the client D mapped to the OTLC 4.4 # 2 area corresponding to the optical SC transceiver 542b-2 of the ODUC4 frame Fb. The multiplexing unit 131b changes the assignment destination of the path of the client D from the TS in the OTLC 4.4 # 2 region to the OTLC 4.4 # 1 region.

  Although the case where the optical SC transceiver 542 of the NNI card 54 has failed has been described above as an example, the same processing is performed when the optical SC transceiver 562 of the transponder 56 fails. Further, the NNI card 54 may use the optical SC transceiver 562 of the transponder 56 as a shared spare, and the transponder 56 may use the optical SC transceiver 542 of the NNI card 54 as a shared spare.

  In addition, the shared standby optical SC transmitter / receiver 542 and the optical SC transmitter / receiver 562 are not defined in advance, and the switching destination of the optical SC transmitter / receiver 542 and the optical SC transmitter / receiver 562 in which the client path is not assigned to the corresponding ODUCn frame area You may choose as

  In this embodiment, the case where one optical channel is n × 100 G and the parallel signal is 100 G has been described as an example. However, the band of the one optical channel and the band of the parallel signal can be arbitrary.

According to the embodiment described above, the optical transmission device includes a plurality of optical signal transmission units that are NNI cards or transponders. When the optical transmission device detects a failure of the transmitter included in the optical signal transmission unit, the shared spare transmitter is set as the traffic switching destination of the failed transmitter, and the failed transmitter is connected to the optical transmitter. Instruct the use of the wavelength used for carrier transmission. The optical signal transmission unit in which the failure of the transmitter has occurred outputs part of the client signal received from one or more clients to the optical signal transmission unit including the switching destination transmitter. The framer of the optical signal transmission unit in which the failure of the transmitter has occurred generates a parallel signal based on the client signal excluding a part that has been output to the optical signal transmission unit having the transmitter of the switching destination, and the failure has occurred. Not output to the transmitter of the optical signal transmitter. The framer of the optical signal transmission unit equipped with the switching destination transmitter generates a parallel signal based on the client signal received from the optical signal transmission unit equipped with the transmitter in which the failure has occurred, and outputs it to the switching destination transmitter To do.
Thereby, one OTUCn signal can be transmitted across a plurality of optical signal transmission units. Therefore, it is possible to realize protection with a high degree of spare sharing for optical subcarriers.

  A part or all of the functions of the OTN framer 521, the OTN framer 541, and the monitoring control unit 60 in the above-described embodiment may be realized by a computer. In that case, a program for realizing this function may be recorded on a computer-readable recording medium, and the program recorded on this recording medium may be read into a computer system and executed. Here, the “computer system” includes an OS and hardware such as peripheral devices. The “computer-readable recording medium” refers to a storage device such as a flexible medium, a magneto-optical disk, a portable medium such as a ROM and a CD-ROM, and a hard disk incorporated in a computer system. Furthermore, the “computer-readable recording medium” dynamically holds a program for a short time like a communication line when transmitting a program via a network such as the Internet or a communication line such as a telephone line. In this case, a volatile memory inside a computer system serving as a server or a client in that case may be included and a program held for a certain period of time. The program may be a program for realizing a part of the functions described above, and may be a program capable of realizing the functions described above in combination with a program already recorded in a computer system.

  The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and includes designs and the like that do not depart from the gist of the present invention.

  It can be used for large-capacity optical transmission.

50 Optical Transmission Device 51 ODU Cross-Connect Function Unit 52 UNI Card 53 ODU-XC
54, 54a, 54b, 54c, 54d, 54e NNI card 55 Optical transmission function unit 56, 56a, 56b Transponder 57 MUX / DEMUX 58 Wavelength XC
59 Hikari AMP
60 Monitoring Control Unit 61 Device Management Information Storage Unit 62 Fault Detection Unit 63 Wavelength Switching Unit 110 Transmission Processing Unit 120 Client Signal Reception Unit 121 Reception Unit 122 Mapping Unit 123 OH Processing Units 130, 130a, 130b Multiplexing Processing Units 131, 131a, 131b Multiplexer 132 Framing unit 140 Line-side transmission processing unit 141 Interleaving units 142-1, 142-2, 142-3, 142-4 OH processing units 143-1, 143-2, 143-3, 143-4 Multilane Transmission unit 150 Reception processing unit 160 Line side reception processing unit 161-1, 161-2, 161-3, 161-4 Multilane reception unit 162-1, 162-2, 162-3, 162-4 OH processing unit 163 Deinterleaving unit 170 Separation processing unit 171 Deframing unit 172 Demultiplexing unit 180 Client signal transmission unit 181 OH processing unit 182 Demapping unit 183 Transmission unit 210 ODU-SW
220 transmitter 230 receiver 521 OTN framer 541, 541a, 541b, 541c, 541d, 541e OTN framer 542, 542a-1, 542a-2, 542a-3, 542a-4, 542b-1, 542b-2, 542b- 3, 542b-4, 542c-1, 542c-2, 542c-3, 542c-4, 542d-1, 542d-2, 542e-1, 542e-2 Optical SC transceivers 561, 561a, 561b OTN framer 562 light SC transceiver 800 OTN framer

Claims (7)

An optical transmission apparatus comprising a plurality of optical signal transmission units each having a framer that generates a plurality of parallel signals and a plurality of transmitters that transmit the plurality of parallel signals generated by the framer by optical subcarriers.
A wavelength switching unit for instructing the transmitter of the switching destination to use the wavelength used by the transmitter in which the failure has occurred for transmission of the optical subcarrier;
The framer of the first optical signal transmission unit which is the optical signal transmission unit including the transmitter in which a failure has occurred,
A part of the client signal received from one or more clients is output to a second optical signal transmission unit which is the optical signal transmission unit including the transmitter to be switched to, and the second optical signal is received from the received client signal. A parallel signal is generated based on the client signal excluding a part of the client signal output to the transmission unit, and the parallel signal in which the client signal is set is used as a failure of the first optical signal transmission unit. A first optical signal generator that outputs to the transmitter not
The framer of the second optical signal transmitter is
E Bei second light signal generating unit which generates a parallel signal, and outputs the generated the parallel signal to the transmitter of the switching destination based on the client signal received from the framer of the first optical signal transmission unit,
The first optical signal generator is
The client signal obtained by removing a part of the client signal output to the second optical signal transmission unit from the received client signal is the time slot in the signal frame of OTUCn (Optical channel Transport Unit-Cn). A first multiplex processing unit that sets the time slot corresponding to the transmitter in which a failure of the first optical signal transmission unit has not occurred;
The signal frame in which the client signal is set by the first multiplex processing unit is divided based on the transmitter to which the time slot in the signal frame corresponds, and a failure of the first optical signal transmission unit occurs A parallel signal corresponding to each of the transmitters that are not, and a first parallel signal generation unit that outputs the parallel signal set with the client signal to the corresponding transmitter,
The second optical signal generator is
The time slot corresponding to the transmitter of the switching destination included in the second optical signal generation unit among the time slots in the signal frame of OTUCn, the client signal received from the framer of the first optical signal transmission unit A second multiple processing unit to be set to
The switching destination provided in the second optical signal transmitter by dividing the signal frame in which the client signal is set by the second multiplex processor based on the transmitter corresponding to the time slot in the signal frame A second parallel signal generation unit that generates a parallel signal corresponding to the transmitter and outputs the parallel signal in which the client signal is set to a corresponding switching destination transmitter.
An optical transmission device characterized by that. The client's path is assigned to the time slot in the signal frame;
The first multiplex processing unit outputs a client signal of the client to which the path is assigned to the time slot corresponding to the transmitter in which a failure has occurred in the signal frame to the second optical signal transmission unit;
The optical transmission device according to claim 1 . The first multiplex processing unit and the second multiplex processing unit are configured to determine the client path allocation destination allocated to the time slot corresponding to the transmitter in which a failure has occurred in the signal frame. Change to the time slot corresponding to the transmitter of the switching destination in the signal frame used by the two-optical signal generation unit,
The optical transmission device according to claim 2 . Receiving information on the failed optical subcarrier from the optical transmission device on the receiving side, detecting the occurrence of a failure in the transmitter using the failed optical subcarrier, and transmitting the failed transmission Comprising a failure detection unit for notifying the first optical signal transmission unit of information on the machine and the switching destination transmitter;
The optical transmission device according to any one of claims 1 to 3 , wherein the optical transmission device is an optical transmission device. A wavelength division function unit that has a colorless function and multiplexes the optical subcarriers output from each of the plurality of transmitters;
The optical transmission device according to any one of claims 1 to 4, characterized in that. Each of the plurality of transmitters includes a port that outputs the optical subcarrier to the wavelength multiplexing function unit.
The optical transmission device according to claim 5 , wherein: An optical signal executed by an optical transmission device including a plurality of optical signal transmission units each including a framer that generates a plurality of parallel signals and a plurality of transmitters that transmit the plurality of parallel signals generated by the framers by optical subcarriers. A transmission method,
A wavelength switching step in which the optical transmission device instructs the switching destination transmitter to use a wavelength used by the transmitter in which the failure has occurred to transmit an optical subcarrier;
The first optical signal generation unit included in the framer of the first optical signal transmission unit, which is the optical signal transmission unit including the transmitter in which the failure has occurred, transmits a part of the client signal received from one or more clients. , Output to the second optical signal transmission unit, which is the optical signal transmission unit including the transmitter to be switched, and remove some of the client signals output to the second optical signal transmission unit from the received client signal Generating a parallel signal based on the client signal, and outputting the parallel signal in which the client signal is set to the transmitter in which a failure of the first optical signal transmission unit has not occurred; ,
The second optical signal generator provided in the framer of the second optical signal transmitter generates a parallel signal based on the client signal received from the framer of the first optical signal transmitter, and generates the parallel signal. A second signal generation step of outputting a parallel signal to the transmitter of the switching destination;
I have a,
The first signal generation step includes
The first multiplex processing unit provided in the first optical signal generation unit obtains the client signal obtained by removing a part of the client signal output from the received client signal to the second optical signal transmission unit from the OTUCn. The first multiplex processing step of setting the time slot corresponding to the transmitter in which the failure of the first optical signal transmission unit has not occurred among the time slots in the signal frame of (Optical channel Transport Unit-Cn) When,
The first parallel signal generation unit provided in the first optical signal generation unit is configured such that the time slot in the signal frame corresponds to the signal frame in which the client signal is set in the first multiplex processing step. Splitting based on a transmitter to generate a parallel signal corresponding to each of the transmitters in which the failure of the first optical signal transmitter does not occur, and transmitting the parallel signal corresponding to the client signal set A first parallel signal generation step to output to the machine,
The second signal generation step includes
The second multiplex processing unit provided in the second optical signal generation unit receives the client signal received from the framer of the first optical signal transmission unit, among the time slots in the signal frame of OTUCn, A second multiplex processing step for setting the time slot corresponding to the transmitter of the switching destination included in the two-optical signal generator;
A second parallel signal generator provided in the second optical signal generator, wherein the time frame in the signal frame corresponds to the signal frame in which the client signal is set in the second multiplex processing step; Dividing based on a transmitter to generate a parallel signal corresponding to the switching destination transmitter included in the second optical signal transmission unit, and transmitting the parallel signal in which the client signal is set to the corresponding switching destination A second parallel signal generation step for outputting to the machine,
An optical signal transmission method.

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