JP3816425B2 - Path capacity changing method and optical wavelength division multiplexing transmission apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an apparatus to which the wavelength multiplexing technology of an OTN transmission system that transmits a signal defined by ITU-T Optical Transport Network NNI or a similar signal is applied, and in particular, a transmission capacity per wavelength is reduced. The present invention relates to a path capacity changing method and an optical wavelength division multiplex transmission apparatus that support a method of changing over time.
[0002]
[Prior art]
A wavelength division multiplexing apparatus is an apparatus whose role is to multiplex a plurality of optical signals in a wavelength region (wavelength multiplexing) and transmit a signal to an opposing wavelength multiplexing apparatus. FIG. 18 shows ITU-T G. 709 is a functional block diagram showing a configuration of a wavelength multiplexing apparatus using a digital frame described in 709 Interfaces of Optical Transport Network (OTN). FIG. The client optical signal is photoelectrically converted in the client interface unit 1, then mapped to an OTU (Optical Transport Unit) frame which is an OTN digital frame, electro-optically converted again, and optically multiplexed in the wavelength multiplexing unit 2. Sent to the transmission line.
[0003]
The wavelength of the light source of the E / O unit on the wavelength multiplexing side of the client interface unit 1 is designed so that the wavelengths of the optical signals multiplexed by the wavelength multiplexing unit 2 do not overlap each other. On the reception side, the received wavelength multiplexed optical signal is separated into wavelengths by the wavelength separation unit 3, guided to a predetermined client interface unit 1 using the optical wavelength as an identifier, and photoelectrically converted, and then the client signal from the OTU frame. Are extracted and sent again as a client optical signal through the electro-optical conversion process.
[0004]
A client interface unit that electrically multiplexes a plurality of client signals can also be used. By using such electrical multiplexing together, the capacity of the system can be increased. For example, a 2.4 Gbit / s client signal is accommodated in OTU1 (2.7 Gbit / s). With OTU2 (10.7 Gbit / s), four 2.4 Gbit / s client signals can be accommodated in ODU1 (Optical Data Unit 1) and multiplexed. The 2.4 Gbit / s client signal accommodated per wavelength (one channel) is 4 times more OTU2 than OTU1 and 16 times OTU3.
[0005]
By the way, in the wavelength division multiplexing transmission apparatus in which OTU1 (2.7 Gbit / s), OTU2 (10.7 Gbit / s), and OTU3 (43 Gbit / s) as shown in FIG. Since it is designed as the strictest OTU3 standard, if the system is used up to the maximum transmission capacity of the system, the OTU3 interface must be used for all wavelengths (channels).
[0006]
However, if the client interface unit of OTU1 (which is cheaper than OTU3) is applied and the bus is opened, the only client signal that can be transmitted at that wavelength (channel) is the corresponding 2.4 Gbit / s client signal. The accommodation efficiency becomes worse.
[0007]
If the interface unit OTU1 is changed to the interface units OTU2 and OTU3 to increase the capacity, the procedure is as follows. First, the opened optical bus is temporarily disconnected. If necessary, the bus is abolished by NW management Ops. Next, the client interface unit OTU2 or OTU3 is replaced with the existing client interface unit OTU1. Then, the optical bus of OTU2 or OTU3 is opened again. In this case, the client signal is unavoidably disconnected for a long time.
[0008]
[Problems to be solved by the invention]
However, in the wavelength division multiplexing transmission apparatus applying the OTN frame according to the prior art, it is easy to realize a large-capacity system using the electric multiplexing function. However, as described above, the wavelength (channel) already used is used. When changing the capacity, the client signal must be cut off. Further, the interruption time is more than the time required for exchanging the client interface, and is not short.
[0009]
The present invention has been made in view of the above-described circumstances, and in an OTN-compliant wavelength division multiplexing transmission apparatus, or in a wavelength division multiplexing transmission apparatus that employs a method of accommodating a client signal in a digital frame as in the case of OTN, An object of the present invention is to provide a path capacity changing method and an optical wavelength division multiplex transmission apparatus that can reduce the interruption time of a client signal or make no interruption when changing the transmission capacity.
[0010]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the invention according to claim 1 The client signal of multiple input optical signals Optical wavelength division multiplexing transmission equipment for wavelength division multiplexing transmission In A wavelength demultiplexing unit for wavelength multiplexing and wavelength demultiplexing of wavelength multiplexed optical signals; A first interface that can be inserted into and removed from the own device, is connected to the wavelength demultiplexing unit, and receives a client signal of an electrical signal, is input from the first interface. A single-type first wavelength multiplexed signal light unit that converts an electrical signal client signal into an optical signal and outputs it to the wavelength demultiplexing unit, and can be inserted into and removed from the own device, One wavelength after the plurality of second interfaces connected to the wavelength demultiplexing unit and receiving client signals of electrical signals are input, and the client signals of electrical signals input from the plurality of second interfaces are electrically multiplexed A second wavelength division multiplexed signal light unit that converts the optical signal into an optical signal and outputs it to the wavelength multiplexing / demultiplexing unit, and a client that inputs and outputs a client signal of the optical signal A issue unit has a third interface which optical signals are input and output, is input from the third interface Optical signal client A first conversion circuit for converting a signal into an electric signal, and a client signal of the electric signal converted by the first conversion circuit. Branch And input to the interface of the wavelength division multiplexed signal light unit that is inserted and connected to the device itself. A branch circuit; A wavelength-division multiplexed signal light unit that has a control command terminal and switches and selects one of the wavelength-multiplexed signal light units that are inserted and connected to the device based on the control command input from the control command terminal; The client signal of the electrical signal input from the signal light unit is output. Selector circuit And a second conversion circuit that converts the client signal of the electrical signal output from the selector circuit into an optical signal and outputs the optical signal to the third interface. With client signal The first wavelength-multiplexed signal light unit includes an electrical signal input from the branch circuit. Client signal An optical signal is converted and output to the wavelength demultiplexing unit, the wavelength multiplexed optical signal input from the wavelength demultiplexing unit is converted into an electric signal, a client signal is read from the converted electric signal, and the read electric signal The client signal is input to the selector circuit , The second wavelength division multiplexed signal light unit is an electric signal input from the branch circuit through any one of the second interfaces. Client signal And other client signals of electrical signals input from the second interface Multiplex The optically multiplexed signal is converted into an optical signal and output to the wavelength demultiplexing unit, the wavelength multiplexed optical signal input from the wavelength demultiplexing unit is converted into an electrical signal, and the converted electrical signal is converted into the client signal unit. The client signal corresponding to is separated, and the separated client signal is input to the selector circuit This is an optical wavelength division multiplexing transmission device.
[0011]
According to a second aspect of the present invention, in the optical wavelength division multiplexing transmission apparatus according to the first aspect, each of the first wavelength division multiplexed signal light unit and the second wavelength division multiplexed signal light unit is connected to the client signal unit. A buffer memory for adjusting the delay time of the client signal supply timing of the first wavelength multiplexed signal light unit and the second wavelength multiplexed signal light unit is a switching source wavelength multiplexed signal A comparison circuit for comparing a delay time of an input signal input to the selector circuit of the client signal unit from the optical unit and the wavelength-division multiplexed signal optical unit of the switching destination, and based on the comparison result of the comparison circuit, It is characterized by changing the buffer memory call timing.
[0012]
According to a third aspect of the present invention, in the optical wavelength division multiplex transmission apparatus according to the second aspect, the WDM optical signal frame is an ITU-T G. 709, and the comparison circuit compares both delay times based on the MFAS byte of the overhead of the OTU frame.
[0013]
According to a fourth aspect of the present invention, in the optical wavelength division multiplexing transmission apparatus according to the second or third aspect, the buffer memory of the wavelength-multiplexed signal light unit of the switching source sets an initial state of the memory amount to the switching source The delay time of the client signal input to the selector circuit from the wavelength multiplexed signal light unit is set to be longer than the delay time of the signal input to the selector circuit from the switching destination wavelength multiplexed signal light unit. When the call timing of the buffer memory is changed, the call timing of the switching destination buffer memory is changed.
[0014]
In the invention according to claim 5, In the above-described invention, insertion into and removal from the own device is possible, and by insertion, the client signal unit and the wavelength demultiplexing unit are connected, and other wavelength multiplexed signal light units A third wavelength multiplexed signal light unit selected from the switching source wavelength multiplexed signal light unit by the selector circuit based on a control command input from the control command terminal It is possible to insert into and out of its own device, connect to the client signal unit and the wavelength demultiplexing unit by being inserted, and based on a control command input from the control command terminal, Immediately before the third wavelength multiplexed signal light unit is selected by the selector circuit. A fourth wavelength-multiplexed signal light unit that handles the same wavelength as that of the wavelength-multiplexed signal light unit and is selected by being switched from the third wavelength-multiplexed signal light unit by the selector circuit. And
[0015]
In order to solve the above-mentioned problems, the invention according to claim 6 Includes a wavelength multiplexing / demultiplexing unit that wavelength-multiplexes / demultiplexes a wavelength-multiplexed optical signal, and a first interface that is connected to the wavelength multiplexing / demultiplexing unit and receives a client signal of an electrical signal. A single-type first wavelength-multiplexed signal optical unit that converts a client signal of an input electrical signal into an optical signal and outputs the optical signal to the wavelength demultiplexing unit, and is connected to the wavelength demultiplexing unit and is an electrical signal client signal The wavelength multiplexing and demultiplexing unit converts the client signal of the electrical signal input from the plurality of second interfaces into an optical signal of one wavelength after being electrically multiplexed. A multiplex type second wavelength multiplexed signal optical unit that outputs to the optical signal and a client signal unit that inputs and outputs an optical signal client signal. A first conversion circuit that has a third interface and converts the client signal of the optical signal input from the third interface into an electrical signal; and the client signal of the electrical signal is branched and inserted into the own device and connected Any one of the wavelength multiplexed signal light units having a branch circuit that inputs to the interface of the wavelength multiplexed signal light unit that is being connected and a control command terminal and connected based on the control command input from the control command terminal A selector circuit that switches between and selects one, and a second converter circuit that is connected to the selector circuit, converts a client signal of an electrical signal output from the selector circuit into an optical signal, and outputs the optical signal to the third interface For changing the path capacity of a client signal of an optical signal in an optical wavelength division multiplex apparatus including a client signal unit having In the quantity changing method, the first wavelength multiplexing signal light unit converts the client signal of the electrical signal input from the branch circuit into an optical signal, and outputs the optical signal to the wavelength multiplexing / demultiplexing unit. The signal light unit multiplexes the client signal of the electrical signal input from the branch circuit through one of the second interfaces and the client signal of the electrical signal input from the other second interface, The multiplexed signal is converted into an optical signal and output to the wavelength demultiplexing / separating unit, and any one of the wavelength multiplexed signal light units connected by the selector circuit based on a control command input from the control command terminal. When the first wavelength multiplexed signal light unit is selected by the selector circuit, the wavelength multiplexing input from the wavelength demultiplexing unit is selected. An optical signal is converted into an electrical signal, a client signal is read from the converted electrical signal, a client signal of the read electrical signal is input to the selector circuit, and the second wavelength multiplexed signal light unit is selected by the selector circuit The wavelength multiplexed optical signal input from the wavelength demultiplexing unit is converted into an electrical signal, the client signal corresponding to the client signal unit is separated from the converted electrical signal, and the separated client signal is input to the selector circuit. The selector circuit inputs the client signal of the electrical signal input from the selected wavelength multiplexed signal light unit to the second conversion circuit. This is a path capacity changing method characterized by the above.
[0016]
According to a seventh aspect of the present invention, in the path capacity changing method according to the sixth aspect, the first wavelength multiplexed signal light unit and the second wavelength multiplexed signal light unit are respectively connected to the client signal unit. A buffer memory for adjusting the delay time of the client signal supply timing is provided, and an input signal input to the selector circuit of the client signal unit from the switching source wavelength multiplexed signal light unit and the switching destination wavelength multiplexed signal light unit And the call timing of the buffer memory is changed based on the comparison result.
[0017]
Further, according to an eighth aspect of the present invention, in the path capacity changing method according to the seventh aspect, the WDM-T G. The OTU frame defined in 709 is used, and both delay times are compared based on the MFAS byte of the overhead of the OTU frame.
[0018]
According to a ninth aspect of the present invention, in the path capacity changing method according to the seventh or eighth aspect, a delay time of a client signal input to the selector circuit from the wavelength-multiplexed signal light unit that is the switching source is the switching capacity. Setting an initial state of the amount of buffer memory of the wavelength-multiplexed signal light unit of the switching source so as to be longer than the delay time of the signal input to the selector circuit from the previous wavelength-multiplexed signal light unit, When the call timing of the buffer memory is changed, the call timing of the switching destination buffer memory is changed.
[0019]
In the invention according to claim 10, In the above-described invention, when switching is performed between the other wavelength multiplexed signal light units, the selector circuit performs switching based wavelength multiplexed signal light based on a control command input from the control command terminal. Switch to a third wavelength multiplexed signal light unit connected to the client signal unit and the wavelength multiplexing / demultiplexing unit, and the selector circuit is configured to switch the third wavelength based on a control command input from the control command terminal. A fourth wavelength multiplex signal light unit that handles the same wavelength as that of the wavelength multiplex signal light unit connected to the client signal unit and the wavelength multiplex separation / separation unit immediately before the third wavelength multiplex signal light unit is selected. Switch to the wavelength division multiplexing signal light section It is characterized by that.
[0020]
In the present invention, a branch circuit for branching the client signal in two and a selector circuit for selecting the client signal from the two wavelength multiplexed signal light sections are provided in the client signal section, and the selector circuit in the client signal section is switched. The wavelength multiplexed signal light unit connected to the client signal unit can be changed to either the first wavelength multiplexed signal light unit or the second wavelength multiplexed signal light unit. Therefore, when changing the transmission capacity of the channel, it is possible to set the client signal interruption time to 1 ms or less or no interruption.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0022]
A. First embodiment
FIG. 1 is a block diagram showing a configuration of an optical wavelength division multiplexing apparatus according to the first embodiment of the present invention. The client interface unit 10 includes an OTU1-IF card 12 that is a wavelength multiplexed signal light unit and a 2.4G client IF card 14 that is a client signal unit. The 2.4G-IF card 14 receives a selector (SEL) 15 that switches two systems of input, a distribution circuit (DIS) 16 that splits one system of input into two, and a control command for switching the selector 15. Terminal 17 to be provided.
[0023]
When the capacity of the client interface unit 10 composed of the two cards is changed (that is, the number of client signals accommodated is increased), the OTU2-IF card 20 having a wavelength (λ2 in the figure) different from that to be changed is used. Prepare and connect the input terminal of the unconnected SEL 15 of the 2.4G client IF card 14, the output terminal of the DIS 16, and a set of input / output terminals of the OTU2-IF card 20. Then, a control command is input from the control command terminal 17 to switch the SEL 15. After switching, the OTU1-IF card 12 is removed from the apparatus and reused.
[0024]
In this method, the time when the client signal is cut off is only the time required for switching the SEL 15 (1 ms or less). Further, in this switching method, when the wavelength multiplexing number of the wavelength multiplexing transmission apparatus is n, the capacity changing operation can be performed without fail by setting the number of wavelengths to be used as n-1. Here, a method of changing from OTU1 to OTU2 has been shown, but it is also possible to change the capacity from OTU2 (four 2.4 Gbit / s client signals) to OTU3, and OTU2 (one 10 G client signal). It is also possible to change the capacity from O) to OTU3. In addition, here, an example of the frame OTU1 expected in ITU-T is shown, but it may not be an OTU frame as long as it is a frame that accommodates a client signal.
[0025]
B. Second embodiment
Next, FIG. 2 is a block diagram showing a configuration of an optical wavelength division multiplexing apparatus according to the second embodiment of the present invention. It should be noted that portions corresponding to those in FIG. In the second embodiment, a phase adjustment memory 21 is provided on the reception side of the OTU1-IF card 12. Further, the ODU1 frame processing unit of the OTU2-IF card 22 is also provided with a memory 23 for phase adjustment. By using these phase adjustment memories 22 and 23, switching is performed without instantaneous interruption so that the client signal is not instantaneously interrupted when the capacity is changed.
[0026]
When the capacity is changed, phase comparison data is input from the OTU1-IF card 12 to the phase comparison circuit 24 provided in the OTU2-IF card 22. For phase comparison, MFAS (Multi Frame Alignment Signal) bytes of Row # 1 Column # 7 defined in the overhead of the OTU frame are used. This byte can identify up to 256 consecutive frames. Alternatively, phase comparison may be performed using other bytes in OH.
[0027]
The capacity of the phase adjustment memories 21 and 23 must be determined in consideration of the difference between the two paths. Here, FIG. 3 and FIG. 4 are conceptual diagrams for explaining a necessary amount of memory for phase adjustment. As can be seen, the OTU1-IF card 12 needs to have more phase adjustment memory 21 than the OTU2-IF card 22. However, since the transmission path passes through the same path, the transmission path delay is not large. G. FIG. 5 shows a calculation example in the case of an apparatus using a 652 fiber and a wavelength in the C-band band. Part of the phase adjustment memory 21 of the OTU1-IF card 12 may be fixed delay. Further, if the amount of the fixed delay is set as follows, the phase adjustment direction is one direction, so that the phase adjustment can be simplified.
[0028]
{OTU1-IF card fixed adjustment memory + OTU1-IF card OTU1 encoding time + fiber transmission delay (wavelength λ1) + OTU1-IF card OTU1 decoding time}> {OTU2-IF card ODU1 encoding time + OTU2-IF card OTU2 encoding time + fiber transmission delay (wavelength λ2) + OTU2-IF card OTU2 decoding time + OTU2-IF card ODU1 decoding time}
[0029]
FIG. 6 shows a block diagram of a phase comparison circuit using EXOR as an implementation example of the phase adjustment circuit when the phase adjustment is in one direction. The EXOR circuit 30 performs an exclusive OR of the client signal CS1 branched by the branch circuit 31 and the client signal CS2 branched by the branch circuit 32. The determination circuit 33 determines whether the client signals CS1 and CS2 match or not according to the output of the EXOR circuit. The output of the EXOR circuit is “High” when both signals completely match, and does not completely become “High” when they do not match.
[0030]
C. Third embodiment
Next, a third embodiment of the present invention will be described. In the third embodiment, the wavelength before the capacity change and the wavelength after the capacity change can be made the same. By making the wavelength the same, for example, it becomes effective in a network in which a plurality of transmission apparatuses are connected, such as a WDM-ring network using optical ADM (add drop max). FIG. 7 is a block diagram showing a configuration of an optical wavelength division multiplexing transmission system when capacity cannot be changed unless the wavelengths are the same. Wavelengths λ1 and λ2 are used between the node 40 and the node 41 and between the node 41 and the node 42. Further, the wavelength λ3 is used between the node 1 and the node 3. When the capacity of the wavelength λ1 channel between the nodes 40 and 41 is increased, if the wavelength λ4 is changed to the wavelength λ4, there is no free wavelength, and therefore the capacity of the channel of the wavelength λ3 between the nodes 40 and 42 can be increased. Disappear.
[0031]
FIG. 8 is a block diagram showing a configuration of an optical wavelength division multiplexing apparatus according to the third embodiment of the present invention. It should be noted that parts corresponding to those in FIG. The difference from the first and second embodiments described above is that a dedicated IF card 50 is used for capacity changing work. The comparison circuit 24 provided in the OTU2-IF card 22 in FIG. 2 may be provided only in both the change work cards 50 as shown in FIG.
[0032]
Next, a procedure for changing work in the third embodiment will be described. Here, it demonstrates with reference to FIG. 9 thru | or FIG. FIG. 9 shows a state where a 2.4 Gbit / s client signal is accommodated in the OTU1 frame. Here, the OTU1-IF card 12 and the 2.4G client IF card 14 are configured. The wavelength of the light source of the OTU1-IF card 12 is λ1. In FIG. 10, the capacity changing work IF card 50 is inserted into the apparatus and connected to the selector 15 and the distribution circuit 16 in the 2.4G client IF card 14.
[0033]
Subsequently, the buffer memory is adjusted by comparison with the delay comparison circuit 24 in the capacity changing work IF card 50, and switching is performed without instantaneous interruption. At this time, the wavelength of the capacity changing work IF card 50 is λn, and λn is reserved for capacity changing work. After the switching operation, the OTU1-IF card 12 is removed as shown in FIG. Next, as shown in FIG. 12, a new OTU2-IF card 22 is inserted, and the client signal is switched from the capacity changing work IF card 50. Finally, as shown in FIG. 13, the capacity changing work IF card 50 is removed.
[0034]
Further, when the client signal is 2.4 Gbit / s when the OTU2 is added to the OTU3, the same capacity changing work IF card 50 can be used. The procedure will be described with reference to FIGS.
[0035]
In FIG. 14, the capacity changing work IF card 50 is inserted into the apparatus and connected to the selector 15 and the distribution circuit 16 in the 2.4G client IF card 14. Subsequently, the buffer memory is adjusted by comparison with the delay comparison circuit 24 in the capacity changing work IF card 50, and switching is performed without instantaneous interruption. After the switching operation, the OTU2-IF card 22 is removed as shown in FIG. Subsequently, as shown in FIG. 16, a new OTU3-IF card 60 is inserted, and the client signal is switched from the capacity changing work IF card 50. Finally, as shown in FIG. 17, the capacity changing work IF card 50 is removed.
[0036]
The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to the above-described embodiment, and includes a design and the like within a scope not departing from the gist of the present invention. .
[0037]
【The invention's effect】
As described above, according to the present invention, the client signal unit includes the branch circuit that branches the client signal in two and the selector circuit that selects the client signal from the two wavelength multiplexed signal light units. By switching the selector circuit, the wavelength multiplexed signal light unit connected to the client signal unit can be changed to either the first wavelength multiplexed signal light unit or the second wavelength multiplexed signal light unit. Therefore, when changing the transmission capacity of the channel, there is an advantage that the time when the client signal is interrupted can be shortened or can be instantaneously interrupted.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration of an optical wavelength division multiplex apparatus according to a first embodiment of the present invention.
FIG. 2 is a block diagram showing a configuration of an optical wavelength division multiplexing apparatus according to a second embodiment of the present invention.
FIG. 3 is a conceptual diagram for explaining a necessary amount of memory for phase adjustment according to the second embodiment.
FIG. 4 is a conceptual diagram for explaining a necessary amount of memory for phase adjustment according to the second embodiment.
[Fig. 5] G. It is a conceptual diagram which shows the example of a calculation in the case of using a 652 fiber and a wavelength C-band apparatus.
FIG. 6 is a block diagram of a phase comparison circuit using EXOR as an implementation example of the phase adjustment circuit when the phase adjustment is in one direction.
FIG. 7 is a block diagram showing a configuration of an optical wavelength multiplexing transmission system when capacity cannot be changed unless the wavelengths are the same in the third embodiment of the present invention.
FIG. 8 is a block diagram showing a configuration of an optical wavelength division multiplexing apparatus according to a third embodiment of the present invention.
FIG. 9 is a block diagram for explaining a procedure of change work in the third embodiment.
FIG. 10 is a block diagram for explaining a procedure of changing work in the third embodiment.
FIG. 11 is a block diagram for explaining a procedure of changing work in the third embodiment.
FIG. 12 is a block diagram for explaining a procedure of change work in the third embodiment.
FIG. 13 is a block diagram for explaining a procedure of change work in the third embodiment.
FIG. 14 is a block diagram for explaining a procedure of change work when adding from OTU2 to OTU3 in the third embodiment;
FIG. 15 is a block diagram for explaining a procedure of a change work when adding from OTU2 to OTU3 in the third embodiment;
FIG. 16 is a block diagram for explaining a procedure of change work when adding from OTU2 to OTU3 in the third embodiment;
FIG. 17 is a block diagram for explaining a procedure of change work when adding from OTU2 to OTU3 in the third embodiment;
FIG. 18 is a functional block diagram showing a configuration of an OTN wavelength division multiplexing transmission apparatus according to a conventional technique.
[Explanation of symbols]
10 Client interface part
12 OTU1-IF card (first wavelength multiplexed signal light unit)
14 2.4G client IF card (client signal part)
15 SEL (selector circuit)
16 DIS (branch circuit)
20 OTU2-IF card (second wavelength multiplexed signal light section)
21,23 Buffer memory
22 OTU2-IF card
24 Comparison circuit
30 EXOR circuit
31 judgment circuit
50 OTU2-IF card for capacity change work (third wavelength division multiplexed signal light section)
60 OTU3-IF card (fourth wavelength multiplexed signal light section)

Claims (10)

In an optical wavelength division multiplex transmission device that transmits wavelength-multiplexed client signals of a plurality of input optical signals ,
A wavelength demultiplexing unit for wavelength multiplexing and wavelength demultiplexing of wavelength multiplexed optical signals;
A first interface that can be inserted into and removed from the own device, is connected to the wavelength demultiplexing unit, and receives a client signal of an electrical signal, is input from the first interface. A single-type first wavelength multiplexed signal light unit that converts a client signal of an electrical signal into an optical signal and outputs the optical signal to the wavelength demultiplexing unit;
A plurality of second interfaces that can be inserted into and removed from the own apparatus, are connected to the wavelength demultiplexing unit, and are input with client signals of electrical signals, are provided from the plurality of second interfaces. A multiplexed second wavelength-multiplexed signal light unit that electrically multiplexes the client signal of the input electrical signal and then converts it to an optical signal of one wavelength and outputs it to the wavelength multiplexing and demultiplexing unit;
A client signal unit for inputting / outputting a client signal of an optical signal,
A first conversion circuit having a third interface for inputting and outputting an optical signal, and converting a client signal of the optical signal input from the third interface into an electrical signal;
A branch circuit that branches the client signal of the electrical signal converted by the first conversion circuit and inputs it to the interface of the wavelength multiplexed signal light unit that is inserted and connected to the own device ;
A wavelength-division multiplexed signal light unit that has a control command terminal and switches and selects one of the wavelength-multiplexed signal light units that are inserted and connected to the device based on the control command input from the control command terminal; A selector circuit for outputting a client signal of an electrical signal input from the signal light unit ;
A client signal unit having a second conversion circuit that converts the client signal of the electrical signal output from the selector circuit into an optical signal and outputs the optical signal to the third interface ;
With
The first wavelength multiplexed signal light unit is
The client signal of the electrical signal input from the branch circuit is converted into an optical signal and output to the wavelength demultiplexing unit, and the wavelength multiplexed optical signal input from the wavelength demultiplexing unit is converted into an electrical signal and converted. Read the client signal from the electrical signal, input the client signal of the read electrical signal to the selector circuit ,
The second wavelength multiplexed signal light unit is
The client signal of the electrical signal input from the branch circuit through any one of the second interfaces and the client signal of the electrical signal input from the other second interface are multiplexed, and the electrically multiplexed signal is optically multiplexed. The signal is converted into a signal and output to the wavelength demultiplexing unit, the wavelength multiplexed optical signal input from the wavelength demultiplexing unit is converted into an electrical signal, and the client signal corresponding to the client signal unit is separated from the converted electrical signal An optical wavelength division multiplex transmission apparatus that inputs the separated client signal to a selector circuit . Each of the first wavelength multiplexed signal light unit and the second wavelength multiplexed signal light unit includes a buffer memory for adjusting a delay time of a client signal supply timing to the client signal unit,
Either one of the first wavelength-multiplexed signal light unit and the second wavelength-multiplexed signal light unit includes the switching source wavelength-multiplexed signal light unit and the switching-destination wavelength-multiplexed signal light unit from the client signal unit. A comparison circuit for comparing delay times of input signals input to the selector circuit;
2. The optical wavelength division multiplex transmission apparatus according to claim 1, wherein a call timing of the buffer memory is changed based on a comparison result of the comparison circuit. The wavelength multiplexed optical signal frame is an ITU-T G.264 standard. 709 is an OTU frame defined in 709,
3. The optical wavelength division multiplexing apparatus according to claim 2, wherein the comparison circuit compares both delay times based on the MFAS byte of the overhead of the OTU frame. The buffer memory of the wavelength-multiplexed signal light unit of the switching source has an initial state of the memory amount, the delay time of the client signal input to the selector circuit from the wavelength-multiplexed signal light unit of the switching source is the switching destination Set to be longer than the delay time of the signal input to the selector circuit from the wavelength multiplexed signal light section of
4. The optical wavelength division multiplexing apparatus according to claim 2, wherein when the call timing of the buffer memory is changed, the call timing of the switching destination buffer memory is changed. Can be inserted into and removed from its own device. When inserted, it is connected to the client signal unit and the wavelength demultiplexing unit, and switching is performed between other wavelength multiplexed signal light units. A third wavelength multiplexed signal light unit selected by switching from the switching source wavelength multiplexed signal light unit by the selector circuit based on a control command input from the control command terminal;
Insertion into the device, removal from the device is possible, connected to the client signal unit and the wavelength demultiplexing unit by being inserted, based on the control command input from the control command terminal, Handles the same wavelength as that of the wavelength-multiplexed signal light unit immediately before the third wavelength-multiplexed signal light unit is selected by the selector circuit, and is switched and selected from the third wavelength-multiplexed signal light unit by the selector circuit A fourth wavelength division multiplexed signal light unit,
5. The optical wavelength division multiplexing transmission apparatus according to claim 1, further comprising: A wavelength multiplexing / demultiplexing unit that wavelength-multiplexes / demultiplexes the wavelength-multiplexed optical signal; and a first interface that is connected to the wavelength multiplexing / demultiplexing unit and receives a client signal of an electrical signal, and is input from the first interface A single-type first wavelength multiplexed signal light unit that converts the client signal of the electrical signal into an optical signal and outputs the optical signal to the wavelength demultiplexing unit; and the client signal of the electrical signal is input to the wavelength demultiplexing unit A plurality of second interfaces, and a client signal of an electric signal input from the plurality of second interfaces is electrically multiplexed and then converted into an optical signal of one wavelength and output to the wavelength demultiplexing unit A second wavelength-multiplexed signal optical unit that performs multiplexing, and a client signal unit that performs input / output of an optical signal client signal. A first conversion circuit that converts the client signal of the optical signal input from the third interface into an electrical signal, and the client signal of the electrical signal is branched and inserted and connected to the own device. A branch circuit that inputs to the interface of the wavelength multiplexed signal light unit, a control command terminal, and one of the wavelength multiplexed signal light units connected based on the control command input from the control command terminal A selector circuit that switches and selects; and a second conversion circuit that is connected to the selector circuit and converts a client signal of an electrical signal output from the selector circuit into an optical signal and outputs the optical signal to the third interface. A path capacity for changing a path capacity of a client signal of an optical signal in an optical wavelength division multiplex transmission apparatus having a client signal section In a further method,
The first wavelength multiplexing signal light unit converts the client signal of the electrical signal input from the branch circuit into an optical signal and outputs the optical signal to the wavelength multiplexing separation unit,
The second wavelength-multiplexed signal light unit receives a client signal of an electric signal input from the branch circuit through any one of the second interfaces and a client signal of an electric signal input from the other second interface. Are converted into an optical signal and output to the wavelength demultiplexing unit,
The selector circuit switches and selects one of the wavelength multiplexed signal light units connected based on a control command input from the control command terminal,
When the first wavelength multiplexed signal light unit is selected by the selector circuit, the wavelength multiplexed optical signal input from the wavelength demultiplexing unit is converted into an electrical signal, and a client signal is read from the converted electrical signal, The client signal of the read electrical signal is input to the selector circuit,
When the second wavelength multiplexed signal light unit is selected by the selector circuit, the wavelength multiplexed optical signal input from the wavelength demultiplexing unit is converted into an electrical signal, and the converted electrical signal is transferred to the client signal unit. Separate the corresponding client signal, input the separated client signal to the selector circuit,
The selector circuit inputs a client signal of an electrical signal input from a selected wavelength multiplexed signal light unit to the second conversion circuit . A buffer memory for adjusting a delay time of a client signal supply timing to the client signal unit is provided in each of the first wavelength multiplexed signal light unit and the second wavelength multiplexed signal light unit,
Compare the delay time of the input signal input to the selector circuit of the client signal unit from the switching source wavelength multiplexed signal light unit and the switching destination wavelength multiplexed signal light unit,
7. The path capacity changing method according to claim 6, wherein the call timing of the buffer memory is changed based on the comparison result.   A frame of the wavelength multiplexed optical signal is referred to as ITU-TG. 8. The path capacity changing method according to claim 7, wherein the delay time is compared based on the MFAS byte of the overhead of the OTU frame as an OTU frame defined in 709. The delay time of the client signal input to the selector circuit from the switching source wavelength multiplexed signal light unit is longer than the delay time of the signal input to the selector circuit from the switch destination wavelength multiplexed signal light unit. So that the initial state of the amount of buffer memory of the switching source wavelength multiplexed signal light unit,
9. The path capacity changing method according to claim 7, wherein when the call timing of the buffer memory is changed, the call timing of the switching destination buffer memory is changed. When the switching is performed between the other wavelength multiplexed signal light units, the selector circuit switches from the switching source wavelength multiplexed signal light unit to the client signal unit based on a control command input from the control command terminal. Switch to a third wavelength multiplexed signal light unit connected to the wavelength demultiplexing unit,
The selector circuit is connected to the client signal unit and the wavelength demultiplexing unit from the third wavelength multiplexed signal light unit based on a control command input from the control command terminal. The path capacity change according to any one of claims 6 to 9 , wherein switching to a fourth wavelength multiplexed signal light unit that handles the same wavelength as that of the wavelength multiplexed signal light unit immediately before the optical unit is selected. Method.

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