JP5004914B2 - Optical cross-connect device and optical network - Google Patents

Description

  The present invention relates to an optical cross-connect device (OXC: Optical Cross Connect or WXC: Wavelength Cross Connect) and an optical network using the same.

  An optical cross-connect device is a device capable of outputting an arbitrary wavelength from an arbitrary output port and / or inputting from an arbitrary input port with respect to an input or output wavelength multiplexed optical signal. A selection switch (WSS: Wavelength Selective Switch) is used. FIG. 14 shows a schematic diagram of an optical network realized by this optical cross-connect device (shown as OXC) 150. A client device 151 is connected to each optical cross-connect device 150 constituting the optical network. The optical cross-connect devices 150 are connected by an optical fiber 152. An optical path 153 is set in the optical fiber 152.

  FIG. 15 shows a functional block diagram of the optical cross-connect device 150. An optical signal by wavelength multiplexing (hereinafter referred to as WDM: Wavelength Division Multiplex) input from N paths on the input side, that is, N optical fibers 152-I1 to 152-IN, is represented by N NNI (Network Node Interface). ) Amplified and demultiplexed in the functional units 160-I1 to 160-IN. The optical switch function unit 161 selects whether the optical signal that has been demultiplexed is to be passed (Through) or extracted (Drop). The optical signal passing through is output to the NNI function units 160-O1 to 160-ON connected to the optical fibers 152-O1 to 152-ON in each of the N paths on the output side. In NNI function part 160-O1-160-ON, it combines with another signal and is amplified. An optical signal to be dropped is converted from a signal format for wide-area transfer into a client signal in a UNI (User Network Interface) function unit 162 and input to the client device 151.

  When an optical signal is newly input (added) to the optical switch function unit 161 from the client device 151 side in the optical cross-connect device 150, the client signal from the client device 151 is a signal for wide-area transfer in the UNI function unit 162. Converted to style. After that, the signal is switched by the optical switch function unit 161 so as to go to the output side NNI function units 160-O1 to 160-ON, and the NNI function units 160-O1 to 160-ON switch to other signals. The signals are combined and input to the optical fibers 152-O1 to 152-ON.

  In order to set the path of the optical path 153 and the wavelength used by the current optical cross-connect device 150, it is necessary to manually switch the optical fibers 152 connected to the optical cross-connect device 150. In recent years, therefore, researches have been actively conducted on highly functional optical cross-connect devices that can arbitrarily set the path of the optical path 153 and the wavelength used from a remote location. In the high-performance optical cross-connect device being studied, in order to realize a function that can output an arbitrary wavelength to an arbitrary path, a large-scale matrix switch or a 1 × that is “1” on the input side and “N” on the output side An apparatus configuration using an N-type WSS is considered.

Paulo Ghelfi, Filippo Cugini, Luca Poti et al, “Optical Cross Connectors architecture with per-Node Add & Drop Functionality”, NTuC3, OFC NFEC 2007.

  In the high-performance optical cross-connect device realized by the large-scale matrix switch as described above, it is necessary to replace the entire switch only when one of the many input / output ports of the matrix switch fails. Switch replacement costs are expensive. In order to add a new path, even if a transponder (TPD) is connected to the client side port of the matrix switch, it is necessary to prepare a new large-scale matrix switch if the switch port is not available. The port expandability is low. Even when the demand for optical paths is small, at least one large-scale matrix switch must be prepared, and it is difficult to reduce capital investment at the beginning of service.

  FIG. 16 shows a configuration example of a highly functional optical cross-connect device 170 using “N + 1” × 1 type wavelength selective switches 171-1 to 171-N, which is a 1 × N type WSS proposed in Non-Patent Document 1. Indicates. The high-performance optical cross-connect device 170 includes WSSs 172 and 173 and a transponder (denoted as “TPD” in the drawing) 174 on the drop side in addition to wavelength selective switches (hereinafter referred to as WSS) 171-1 to 171-N. The optical couplers 175-1 to 175-N are provided on the input path (Input) side, and the transponder 176, the optical coupler 177 (OC and illustration) and the optical splitter (Splitter and illustration) 178 are provided on the Add side. . Since the number of WSSs required in this configuration is small and the number of WSSs 171-1 to 171-N through which optical signals pass is small, the device configuration is inexpensive and low loss. However, in the Add / Drop port for adding or extracting optical signals, the optical signals from each UNI port or each path are collected by the optical coupler 177 and WSS 173, so that wavelength collision occurs (Blocking configuration). Therefore, there is a problem that wavelength resources cannot be effectively used. For example, since the same wavelength cannot be overlapped in the optical coupler 177, there is a restriction on wavelength blocking that the same wavelength signal cannot be added to the same node.

  From the above, in the configuration of the conventional high-performance optical cross-connect device using a large-scale matrix switch and the high-performance optical cross-connect device 170 using 1 × N type WSS, both high port scalability and non-blocking configuration can be achieved. It has become a challenge.

  The present invention has been made under such a background, and an object thereof is to provide an optical cross-connect device and an optical network that achieve both port expandability and a non-blocking configuration.

  The optical cross-connect device of the present invention receives wavelength multiplexed signals from N (N ≧ 2) NNI side input paths and α (α ≧ 1) UNI side input paths, and receives the received wavelength. In an optical cross-connect device that selects an output route for each wavelength of a multiplexed signal and transmits wavelength multiplexed signals to N NNI output routes or α UNI output routes, one N input N + α demultiplexing member (α ≧ 1), N N + α inputs with one output multiplexing member, and k (α ≧ k ≧ 1) N inputs with m (m ≧ 2) output And a second wavelength selective switch of k (α ≧ k ≧ 1) m (m ≧ 2) inputs and N outputs, and includes a demultiplexing member and a multiplexing member. At least one of them is composed of a wavelength selective switch, and the demultiplexing member is connected to the input path on the NNI side to one input port and N output ports. Are connected to the N multiplexing members, the remaining α output ports are connected to the first wavelength selective switch, and the multiplexing member connects the outputs of the N demultiplexing members to the N input ports. The output of the second wavelength selective switch is connected to the remaining α input ports, one output port is connected to the output path on the NNI side, and the first wavelength selective switch has N input ports. The output of the demultiplexing member is connected to each other, one receiver is connected to each of the m output ports, and the second wavelength selective switch is connected to the output of one transmitter to each of the m input ports, A multiplexing member is connected to N output ports.

  In the optical cross-connect device of the present invention, the branching member can be provided with an optical branch circuit having one input and an output of N + α. Alternatively, in the optical cross-connect device of the present invention, the multiplexing member can be provided with an optical combining circuit with one output at N + α input. For example, in the optical cross-connect device of the present invention, k is 2 or more and α or less.

  Further, the optical cross-connect device of the present invention is a case where the branching member has one input and N + 1 outputs, and the branching member and the first wavelength selective switch have N one inputs and light of 1 + k output. It can be connected with a coupler.

  Alternatively, in the optical cross-connect device according to the present invention, the multiplexing member has N + 1 inputs and one output, and the second wavelength selective switch and the multiplexing member have N 1 + k inputs and one output light. It can be connected with a coupler.

  Further, in the optical cross-connect device of the present invention, the first wavelength selective switch and the second wavelength selective switch include an optical demultiplexer having the number of input ports, an optical multiplexer having the number of output ports, and a wavelength. It can be configured by a matrix switch of “number of input ports × number of output ports” of the number of multiplexing.

  In the optical cross-connect device of the present invention, the first wavelength selective switch includes an optical demultiplexer having the number of input ports and a matrix switch of “product of the number of input ports and the number of multiplexed wavelengths × the number of output ports”. The second wavelength selective switch can be configured by an optical demultiplexer having the number of output ports and a matrix switch of “the product of the number of output ports and the number of multiplexed wavelengths × the number of input ports”.

  In the optical cross-connect device of the present invention, the first wavelength selective switch is composed of one input corresponding to the number of input ports and a wavelength selective switch corresponding to the number of output ports, and optical combiners corresponding to the number of output ports. In addition, the second wavelength selective switch can be composed of a wavelength selective switch that outputs one output by the number of input ports corresponding to the number of output ports and an optical demultiplexer that corresponds to the number of input ports.

  In the optical cross-connect device according to the present invention, the second wavelength selective switch includes one input for the number of input ports and an output for the number of output ports and an input for the number of output ports. It can be composed of a single output optical combiner.

  In the optical cross-connect device according to the present invention, the first wavelength selective switch includes an optical shunt that outputs one input by the number of input ports and outputs by the number of output ports, and inputs by the number of output ports. Thus, the optical switch can be configured with one output optical switch and the number of wavelength selection filters corresponding to the number of output ports.

  Also, the optical network of the present invention is an optical network using the optical cross-connect device of the present invention, wherein a working path and a backup path are formed between different optical cross-connect devices, and a transmitter of the working path and a transmitter of the backup path Are respectively connected to different second wavelength selective switches, and the receiver of the working path and the receiver of the protection path are respectively connected to the different first wavelength selective switches.

  According to the present invention, it is possible to realize both the port expandability and the non-blocking configuration at the same time, and to improve the switch fault tolerance and the switch replacement cost at low cost and simply.

(First embodiment of the present invention)
A configuration of an optical cross-connect device (hereinafter referred to as OXC) 1 according to a first embodiment of the present invention will be described with reference to FIG. FIG. 1 is a block diagram of OXC1.

  This OXC1 has an N × M WSS11 with N inputs and M outputs at the Drop portion, and an M × N WSS12 with M inputs and N outputs at the Add portion. It is what was used. The OXC 1 includes N optical couplers 13-1 to 13 -N on the input path (Input) side, N “N + 1” × 1 type WSSs 14-1 to 14 -N on the output path (Output) side, M receivers 15-1 to 15 -M composed of transponders that receive optical signals from N × M WSS 11 for Drop, and transponders that transmit optical signals to M × N WSS 12 between Add And M transmitters 16-1 to 16-M. Here, the N × M WSS 11 is a first wavelength selective switch, and the M × N WSS 12 is a second wavelength selective switch.

  OXC1 receives WDM optical signals from N (N ≧ 2) input routes (= N routes), and once demultiplexes the received WDM optical signals to select an output route for each wavelength. Then, the signals are multiplexed again and WDM optical signals are transmitted to a plurality of N output routes (= N routes). Further, the optical signal output to the M (M ≧ 1) output routes arranged on the client side is demultiplexed from the WDM optical signal and inputted from the M input routes arranged on the client side. The optical signal is multiplexed with the WDM optical signal. Here, the optical couplers 13-1 to 13 -N are respectively demultiplexing members, and “N + 1” × 1 type WSSs 14-1 to 14 -N are respectively demultiplexing members.

  The N × M WSS 11 demultiplexes and multiplexes the WDM optical signals input from the N input ports within the N × M WSS 11, and then selects an arbitrary WDM from any of the M output ports. It is a device that can output optical signals and single wavelength light. Further, the M × N WSS 12 multiplexes / demultiplexes single-wavelength light input from any of the M input ports within the M × N WSS 12, and then outputs the N output ports. It is a device that can output WDM optical signals and single wavelength light from any port. The optical couplers 13-1 to 13 -N simply branch the input WDM optical signal into the number “N + 1”.

  Further, instead of the optical couplers 13-1 to 13 -N illustrated in FIG. 1, a 1 × “N + 1” type WSS may be used. In this case, the same WSS input / output as the “N + 1” × 1 type WSS 14-1 to 14-N can be used in reverse.

  FIG. 2 shows an example of the internal configuration of the N × M WSS 11. The M × N WSS 12 has the same configuration. The N × M WSS 11 in FIG. 2 includes N 1 × M WSSs 21 and M N × 1 WSSs 22. The WDM optical signal from the N route is input to the 1 × M WSS 21 connected to the optical fiber of each route, and is input to the N × 1 WSS 22 connected to each optical fiber of the M route. . At this time, any wavelength from any 1 × M WSS 21 can be input to any N × 1 WSS 22. The input wavelengths are combined in the N × 1 WSS 22 and input to the optical fiber.

  Further, the N × M WSS 11 becomes the M × N WSS 12 by being configured as follows. That is, the WDM optical signal from the M route is input to the N × 1 WSS 22 connected to the optical fiber of each route, and is input to the 1 × M WSS 21 connected to each optical fiber of the N route. Is done. At this time, any wavelength from any N × 1 WSS 22 can be input to any 1 × M WSS 21. The input wavelengths are combined in the 1 × M WSS 21 and input to the optical fiber.

(Description of operation of OXC1)
Next, the operation during normal operation of the OXC 1 in FIG. 1 will be described. The WDM optical signals input from the optical fiber on the input path (Input) side are output by the optical couplers 13-1 to 13 -N and the number of output paths (Output) and the number of N × M WSSs 11 for Drop. The sum branches (one in FIG. 1). The WDM optical signal output to the output route (Output) side is input to “N + 1” × 1 type WSSs 14-1 to 14-N.

  The WDM optical signal output to the drop N × M WSS 11 is demultiplexed in the N × M WSS 11, and only the optical signal to be dropped is arbitrarily output from the M output ports. The optical signal output from the N × M WSS 11 is accommodated in a transponder as the receiver 15-1 to 15-M and converted into a client signal.

  When an optical path is added (Add), an optical signal is input from a transponder as a transmitter 16-1 to 16 -M connected to an arbitrary input port of the M × N WSS 12 for Add. The input optical signal is wavelength-multiplexed for each arbitrary output port. The WDM optical signal output from the M × N WSS 12 is output along with the WDM optical signal branched by the optical couplers 13-1 to 13 -N on the input path (Input) side. N + 1 "× 1 type WSS 14-1 to 14-N. The WDM optical signals input to “N + 1” × 1 type WSSs 14-1 to 14 -N on the output path (Output) side are combined and output.

  The dropped optical signal is removed in the M × N WSS 11. After that, the optical signals other than the dropped optical signal are multiplexed in the “N + 1” × 1 type WSS 14-1 to 14-N on each output side and connected to the outputs of the “N + 1” × 1 type WSS 14-1 to 14-N. Input to optical fiber.

  In the OXC1 using the N × M WSS11 and the M × N WSS12 shown in FIG. 1 described above, a higher port than the configuration using the conventional large-scale matrix switch or the configuration using the 1 × N WSS is used. It is possible to achieve both scalability and a non-blocking configuration.

  When the number of ports on the receivers 15-1 to 15-M or the transmitters 16-1 to 16-M side is insufficient for the path demand, in the conventional large-scale matrix switch configuration, a matrix switch of the same scale is added. There is a need. On the other hand, in order to increase the ports on the receivers 15-1 to 15-M or transmitters 16-1 to 16-M side in the configuration of FIG. 1, add N × M WSS11 or M × N WSS12. The port can be expanded. Assuming that the same wavelength light enters the OXC 1 simultaneously from each path on the input side, in the conventional configuration shown in FIG. The optical coupler 177 once aggregates the WDM optical signals input to Add. For this reason, wavelength blocking occurs in the OXC 170. On the other hand, in the configuration of FIG. 1, WDM optical signals from each input side are collected in the N × M WSS 11, but wavelength blocking does not occur in the N × M WSS 11 as shown in FIG. , Non-blocking configuration. In addition, since the M × N WSS 12 is used instead of the optical coupler 177 for the Add portion, the non-blocking configuration is similarly applied.

(Second embodiment of the present invention)
The OXC 1A according to the second embodiment of the present invention has an N × m WSS or an m × N WSS obtained by dividing a package of an N × M WSS having N inputs or outputs and M outputs or inputs. It is what was used. As shown in FIG. 3, OXC1A is an N × m WSS 31-1 to 31-α obtained by dividing N × M WSS into α packages and an m × N method obtained by dividing M × N WSS into α packages. WSS 32-1 to 32-α (where m <M), 1 × “N + α” type WSS 33-1 to 33-N on the input route (Input) side, and “N + α” on the output route (Output) side × 1 type WSS34-1 to 34-N, m receivers 35-11 to 35-1m corresponding to N × m type WSS33-1 on the drop side, and N × m type WSS31-α on the same drop side M receivers 35-α1 to 35-αm corresponding to, m transmitters 36-1 to 36-m corresponding to the m × N WSS 32-1 on the Add side, and m × on the Add side as well. M transmitters 36-α1 to 36-αm corresponding to N-type WSS32-α

  In FIG. 3, instead of the 1 × “N + α” type WSSs 33-1 to 33-N connected to the input-side optical fiber, an optical coupler that can branch into “N + α” may be used. Alternatively, instead of “N + α” × 1 type WSS 34-1 to 34-N connected to the output side fiber, an optical coupler capable of inputting “N + α” may be used. A plurality of α N × m-type WSSs 31-1 to 31-α and α m × N-type WSSs 32-1 to 32-α are gathered, and the N × M-type WSS11 and the M × N-type WSS12 shown in FIG. Demonstrate the same performance. The N × m WSS 31-1 to 31-α and the m × N WSS 32-1 to 32-α communicate with each other by an electric signal, and which N × m WSS 31-1 to 31-α and which m × All N × m WSS31-1 to 31-α and m × N WSS32-1 to 32-α indicate which wavelength is added or dropped from which port in N-type WSS32-1 to 32-α. I know.

  Compared to the configurations of the N × M WSS 11 and the M × N WSS 12 in FIG. 1, the configurations of the N × m WSS 31-1 to 31-α and the m × N WSS 32-1 to 32-α in FIG. It is excellent in terms of 1) switch replacement cost, (2) port expandability, and (3) switch fault tolerance. Hereinafter, three merits by applying the N × m WSS 31-1 to 31-α and the m × N WSS 32-1 to 32-α will be described.

(About the benefits of switch replacement costs)
N × m WSS31-1 to 31-α and m × N WSS32-1 to 32-α (hereinafter referred to as “N × m WSS” when both are described together) are N × M WSS11. The M × N WSS 12 is divided into packages. For this reason, the switch parts used for the internal configuration of the N × m-type WSS are more parts and output (input) ports than the N × M-type WSS11 and the M × N-type WSS12 using the same switch parts. Become smaller. As a result, N × m type WSS 31-1 to 31-α and m × N type WSS 32-1 to 32-α (hereinafter, in order to indicate the whole or a part of each, simply “31” or “32” It is possible to keep the replacement cost lower.

(About the benefits of port expandability)
Further, the receiver 35-11 to 35-αm (hereinafter, the whole or a part thereof is simply denoted by “15”) and / or the transmitter 36-11 to 36-αm (hereinafter referred to as these). When the port on the side is expanded, the number of ports on the client side has a relationship of m <M. Therefore, when the port on the side is expanded, the N × M WSS11 or M × Compared to the N-type WSS 12, the number of ports can be expanded flexibly. That is, m ports can be expanded by m. In the configuration example of the OXC 1A in FIG. 3, in order to increase the number of ports of the switch on the UNI side, when an N × m WSS is added, an m × N WSS 32 for Add and an N × mS WSS 31 for Drop are used. Are required in pairs. The m × N WSS 32 for Add connects the output N ports one by one to N “N + α” × 1 WSS 34 connected to the optical fiber on the output side. Similarly, the N × m WSS 31 for Drop connects the input N ports one by one to N “N + α” × 1 WSS 33 connected to the fiber on the input side.

(Advantages of switch fault tolerance)
When the N × M WSS11 or the M × N WSS12 fails, at least M receivers 15-1 to 15-M are transmitted when the N × M WSS11 or the M × N WSS12 is replaced. Communication interruption occurs in the operation of the machines 16-1 to 16-M. On the other hand, if the N × m WSS 31 or the m × N WSS 32 fails in the configuration of the N × m WSS 31-1 to 31 -α or the m × N WSS 32-1 to 32 -α, an instantaneous interruption occurs. The number of receivers 35 and transmitters 36 can be reduced to m. When setting redundant paths, working path receivers 35-11 to 35-1m, ..., 35-α1 to 35-αm, transmitters 36-11 to 36-1m, ..., 36-α1 to 36-αm , 35-α1 to 35-αm, and receivers 35-11 to 35-1m,..., 35-α1 to 35-1m,. Connect to N × m WSS31 or m × N WSS32. As a result, a single package failure can be completely remedied without taking a switch redundant configuration. From the above, in both cases of switch failure and redundant path setting, N × m WSS 31-1 to 31-α, m × N equation compared to the configuration using N × M WSS 11 and M × N WSS 12 The WSS 32-1 to 32-α can reduce the number of receivers 35 and transmitters 36 that are affected. As described above, only m receivers 35 and transmitters 36 are affected at most.

  Here, a range of possible values of the number m of client side ports of the N × m WSS 31 and the m × N WSS 32 will be described. In FIG. 3, the number of paths N, the number of wavelength multiplexing λ, the number of package divisions α (the number of N × m WSSs required to realize the same performance as one N × M, where M = αm) Then, the condition of the number of ports m for the OXC 1A to which the N × m WSS 31 or the m × N WSS 32 is applied has a non-blocking configuration (a configuration capable of dropping all wavelengths λN from all routes) is m = λN / α.

  At this time, the number of output ports of the 1 × “N + 1” type WSS 33 on the NNI side and the number of input ports of “N + α” × 1 type WSS 34 are N + α (the number of routes + the number of N × m type WSSs), respectively. At present, the number of ports of the 1 × “N + 1” type WSS 33 and the “N + α” × 1 type WSS 34 is about 9 at most, and the number of routes of the OXC 1A is considered to be N = 4. Here, if ports are allocated to the N × m WSS on the UNI side by the number obtained by subtracting the number of NNI routes from the number of WSS ports, α = 9−4 = 5. Therefore, if λ = 40 at this time, the number of client-side ports of the N × m WSS 31 and the m × N WSS 32 is m = 40 × 4/5 = 32. Considering that the number of input (output) ports of WSSs 33 and 34 will be about 20 in the future, λ = 40, N = 4, α = 20−4 = 16, and m = 10 (= 40 × 4 ÷ 16). From the above, the possible range of m is 10 ≦ m ≦ 32 considering the current situation and the near future. However, when considering the distant future, this range may be exceeded.

(Third embodiment of the present invention)
The OXC 1B according to the third embodiment of the present invention receives WDM optical signals from N (N ≧ 2) NNI side input paths, and once demultiplexes the received WDM optical signals. Select an output path for each wavelength, recombine, and transmit a WDM optical signal to a plurality of N NNI output paths, and from α (α ≧ 1) UNI input paths The input optical signal is multiplexed with the WDM optical signal, and the optical signal output from the WDM optical signal to the α UNI output paths is demultiplexed from the WDM optical signal. This point is the same as in the second embodiment. Hereinafter, the same members as those described in the second embodiment will be described with the same reference numerals.

  This OXC1B is composed of α N × m WSS 31-1 to 31-α obtained by dividing N × M WSS into α and α m × N obtained by dividing M × N WSS into α. Formulas WSS32-1 to 32-α, receivers 35-11 to 35-1m, ..., 35-α1 to 35-αm, transmitters 36-11 to 36-1m, ..., 36-α1 to 36-αm N 1 × “N + 1” type WSSs 43-1 to 43-N on the input route side (Input) side and N “N + 1” × 1 type WSSs 44-1 to 44-N on the output route side (Output) side -N, N optical couplers 46 on the drop side, and N optical couplers 47 on the add side. This OXC1B is obtained by suppressing the increase in the number of input / output ports of the switch on the NNI side by adding optical couplers 46 and 47 to OXC1A. Hereinafter, this point will be described.

  In the OXC 1A of FIG. 3, when the number of N × m WSS 31 and m × N WSS 32 increases, that is, when the number of package divisions increases, the output / input of each NNI side switch connected to the input / output optical fiber It is necessary to increase the number of ports. Therefore, when using a plurality of N × m WSS 31 and m × N WSS 32 in the OXC 1A of FIG. 3, an example of the configuration of the NNI switch for the purpose of suppressing an increase in the number of input / output ports of the NNI switch As shown in FIG.

  A WDM optical signal entering the node through the optical fiber 48 is input to an input port of a 1 × “N + 1” type WSS 43 that is an NNI side switch connected to the input side optical fiber 48. The WDM optical signal is demultiplexed in the 1 × “N + 1” WSS 43, switched for each wavelength, and output from the output port of the 1 × “N + 1” WSS 43. At this time, a WDM optical signal (optical signal that goes through the node) directed to the NNI switch on the output side is output from a different port for each output route, whereas a plurality of optical signals that are dropped at the node are summarized. Output from one port as a WDM optical signal. The Drop optical signals output together are input to the optical coupler 46 and branched to a plurality of N × m WSSs 31-1 to 31 -α for Drop. In this method, even if the number of N × m WSSs 31 is α, by preparing N optical couplers 46 that branch α, each WSS 43 requires an output port that is “+1” for the N route. Only “α” pieces are not required as shown in FIG.

  When the number of N × m-type WSSs 31 is larger than the number of branches of the optical coupler 46, the number of output ports that collectively output optical signals dropped at the node in the 1 × “N + 1” -type WSS 43 on the NNI side is increased. The output WDM optical signals are branched by the optical coupler 45 and input to the N × m WSS 31.

  From the above, by applying the configuration shown in FIG. 5 to the NNI switch connected to the input-side optical fiber 48, it is possible to suppress an increase in the number of output ports of the NNI switch. The output side NNI switch configuration shown in FIG. 6 is also the same as in FIG.

  Here, the OXC 1B shown in FIG. 4 will be described. As described above, the OXC 1B includes 1 × “N + 1” -type WSSs 43-1 to 43-N which are demultiplexing members of “N + α” output (α ≧ 1) with N one input, and N “N + α”. “N + 1” × 1 type WSS 44-1 to 44-N, which is a 1-output multiplexing member, and m (m ≧ 2) output first with k (α ≧ k ≧ 1) N inputs. N × m-type WSSs 31-1 to 31-α that are wavelength selective switches, and m × N-type WSS32-132-α that is a second wavelength selective switch of N outputs with k m (m ≧ 2) inputs, have.

  In the 1 × “N + 1” type WSSs 43-1 to 43-N, the NNI side input path is connected to one input port, and N output ports are connected to N “N + 1” × 1 type WSS44-1. To 44-N, and the remaining α (one in this embodiment) output ports are connected to one optical coupler (OC and illustrated) 46. “N + 1” × 1 WSSs 44-1 to 44-N connect N 1 × “N + 1” WSS 43-1 to 43-N outputs to N input ports, and the remaining α (in this embodiment) One output port of the optical coupler (OC and illustration) 47 is connected to one input port, and one output port is connected to the NNI side output route. The N × m WSSs 31-1 to 31 -α connect the outputs of 1 × “N + 1” WSSs 43-1 to 43-N to the N input ports via the optical coupler 46, and connect them to the m output ports. One receiver 35 is connected to each. The m × N WSSs 32-1 to 32-α connect the outputs of one transmitter 36 to m input ports, respectively, and “N + 1” × 1 WSS 44 via the optical coupler 47 to the N output ports. -1 to 44-N are connected. The receivers 35-11 to 35-1m,..., 35-α1 to 35-αm, and the transmitters 36-11 to 36-1m,..., 36-α1 to 36-αm are transponders (TPD).

  In the example of FIG. 4, as described above, between the 1 × “N + 1” type WSSs 43-1 to 43-N and the N × m type WSSs 31-1 to 31-α, and the m × N type WSS32− A “1 × k” type optical coupler 46 and a “k × 1” type optical coupler 47 are inserted between 1 to 32 -α and “N + 1” × 1 type WSSs 44-1 to 44-N. The “1 × k” optical coupler 46 is an optical coupler that branches one optical signal into k, and the “k × 1” optical coupler 47 combines k optical signals into one.

  7, 8, and 9 show examples of the internal configuration of the N × m WSS. In the internal configuration example 1 of the N × m WSS in FIG. 7, when the N route is an input and the m route is an output (N × m WSS 31 for Drop), the WDM from each optical fiber of the N route An N × m Matrix SW (N × m matrix) prepared by demultiplexing an optical signal for each wavelength by an AWG (Arrayed Waveguide Grating) 50 connected to an optical fiber, and for the number of multiplexed wavelengths. Switch) 51 for each wavelength. That is, one N × m matrix switch 51 handles one wavelength of the same wavelength that enters from each path. For example, the wavelength λ1 is input to the first N × m matrix switch 51a, and the wavelength λ2 is input to the second N × m matrix switch 51b.

  In the N × m matrix switch 51, the input optical signal is output to the AWG 52 connected to the m-path output optical fiber. The optical signals are multiplexed for each AWG 52 on the m route, output to the m route, and input to the client. When the m route is an input and the N route is an output (m × N WSS 32 for Add), the operation is the same as the N × m WSS 31 for Drop.

  In the internal configuration example 2 of the N × m WSS 31 in FIG. 8, in the case of the N × m WSS 31 for Drop, a WDM optical signal input from the N route is connected to the optical fiber of each route. Demultiplexing using the AWG60. All the demultiplexed optical signals are input to one N × m matrix switch 61 and switched to an m-path output. In the case of the m × N WSS 32 for Add, single wavelength light from the client side is input from the m route to the N × m matrix switch 61 and input to an arbitrary AWG 60 connected to the output N route. The switching is performed in the N × m matrix switch 61. The single wavelength light output from the N × m matrix switch 61 is combined in the AWG 60 of each route, and is output as a WDM optical signal for each route.

  In the internal configuration example 3 of the N × m WSS in FIG. 9, in the case of the N × m WSS 31 for Drop, N input WDM optical signals from the N path are respectively connected to the input optical fibers. Using 1 × m WSS 70, branching and route selection are performed. An N × 1 type optical coupler (N × 1 type OC is shown) 71 or an N × 1 type switch (N × 1 type SW is shown) 72 is connected to each of the output m paths. The signal light output from the xm-type WSS 70 is combined and selected and input to the optical fiber. In the case of the N × m WSS 32 for Add, single-wavelength light input from the m route is an arbitrary 1 × connected to each output N route by the N × 1 optical coupler 71 or the N × 1 switch 72. Output to m-type WSS 70. The 1 × m WSS 70 connected to each output route combines any single wavelength input from the m route and outputs it as a WDM optical signal.

  The internal configuration example of the N × m WSS shown in FIGS. 7, 8, and 9 is a configuration that can support both Add / Drop, and is realized using a WSS or a matrix switch. However, a configuration that realizes one of the operations of Add and Drop can be realized more inexpensively and simply.

  FIG. 10 shows a configuration in a case where only the Add function of the m × N WSS 32 (input is limited to m route and output is limited to N route). As for the single wavelength input from the m route to which the transmitter 36 is connected, the output N route can be selected by a 1 × N switch (shown as 1 × N SW) 80. An m × 1 type optical coupler (shown as m × 1 type OC) 81 is connected to the optical fiber of the output route, and a single wavelength output from the 1 × N type SW 80 is m × 1 for each output route. The optical signal is combined by the optical coupler 81 and input to the N-path output fiber as a WDM optical signal.

  FIG. 11 shows a configuration for realizing the drop function of N × m WSS 31 (input is limited to N route and output is limited to m route). A WDM optical signal input from an N-path optical fiber is branched into an m-path by a 1 × m optical coupler (shown as a 1 × m OC) 90. The branched WDM optical signal is input to m N × 1 type switches 91, and the N × 1 type switch 91 selects which WDM optical signal is output. The WDM optical signal selected by the N × 1 type switch 91 is output from the N × 1 type switch 91 and is then filtered by the tunable filter (wavelength variable filter) 92 except for the single wavelength that is output to the m path. . The single wavelength selected by the tunable filter 92 is output from the m path and input to the receiver 35.

(Optical network using N × m WSSs according to the second and third embodiments of the present invention)
FIG. 12 shows an example of an optical network using OXC 1A and 1B (hereinafter simply referred to as OXC) using N × m WSS 31 and m × N WSS 32. The optical network of FIG. 12 is configured in a ladder shape by six OXC # A, OXC # B, OXC # C, OXC # D, OXC # E, and OXC # F. The OXCs are connected by two optical fibers 95. When constructing an optical path in this optical network, the optical path is realized by bidirectional communication.

  In the optical network of FIG. 12, an optical path is formed between OXC # C and OXC # D. The working path is formed on the path OXC # C-OXC # B-OXC # A-OXC # D using the wavelength λW. A backup path is formed simultaneously with the working path. The backup path is formed in the route of OXC # C-OXC # F-OXC # E-OXC # D using the wavelength λP. The wavelength λP = wavelength λW may be used.

  In this optical network, “1 + 1” protection is used as a working path redundancy means for a failure in the transmission path such as the disconnection of the optical fiber 95. That is, the transmission side OXC allows the same traffic to flow through the working path and the protection path, and by selecting either the working path or the protection at the reception side OXC, communication can be continued even if the working path fails. Even if the UNI side N × m WSS 31 or the m × N WSS 32 breaks down, communication can be continued in the same manner.

  FIG. 13 shows a configuration example of the OXC that forms the optical network of FIG. In the OXC configuration example of FIG. 13, OC is optical couplers 100-1 and 100-2, WSS is wavelength selective switches 101-1 and 101-2, and TPD is wavelength variable transponders 102-1 to 102-4, 1 × 2. The expression Splitter indicates the 1 × 2 type optical splitter 103, and the 1 × 2 type Selector indicates the 1 × 2 type optical selector 104. The m × N WSSs 105-1 and 105-2 and the N × m WSSs 105-3 and 105-4 use a total of four units for transmission / reception of a pair of working paths and backup paths.

  The normal operation of OXC # C and OXC # D in the optical network of FIG. 12 will be described. When transmitting a client signal from the client side, it is divided by the 1 × 2 optical splitter 103 and sent to the two transponders 102-1 and 102-2. Next, the client signal is converted into a signal format for wide-area transfer by the transponders 102-1 and 102-2, and the traffic accommodated in the working path is assigned the wavelength λW, and the traffic accommodated in the backup path is assigned the wavelength λP. It is done. The two transponders 102-1 and 102-2 are connected to different m × N WSSs 105-1 and 105-2, the working path is m × N WSS 105-2, and the backup path is m × N. Input to each WSS 105-1. The working wavelength signal input to the m × N WSS 105-2 is switched to the WSS 101-1 connected to the optical fiber 95 on the output side that is the path of the working path. The standby wavelength signal input to the m × N WSS 105-1 is input to the WSS 101-2 and switched. The working and protection paths output from the m × N WSSs 105-1 and 105-2 are respectively input to the WSSs 101-1 and 101-2 connected to the different optical fibers 95 on the output side, and the wavelength signals to shoot this OXC. Is combined. Thereafter, it is output as a wavelength multiplexed signal to the optical fiber 95 in a different path.

  On the other hand, when receiving traffic with the configuration of FIG. 13, the optical couplers 100-1 and 100-2 branch the WDM optical signal input from the optical fiber 95 on the input side. The branched WDM optical signals are output to the WSSs 101-1 and 101-2 and the N × m WSSs 105-3 and 105-4 connected to the output routes. In the WSSs 101-1 and 101-2 connected to the output-side optical fiber 95, wavelength signals other than the wavelengths λW and λP to be dropped by this OXC are Thrown. In the N × m WSSs 105-3 and 105-4, among the input WDM optical signals, the wavelength signals of wavelengths λW and λP are output to the output port to which the transponders 102-3 and 102-4 are connected. Switched to The transponders 102-3 and 102-4 convert the input wavelength signals λW and λP into client signals and output them to the 1 × 2 selector 104. Normally, traffic on the working path output from the N × m WSS 105-3 is selected.

  Next, the operation of this OXC when a failure occurs in any one or a plurality of m × N WSSs 105-1 and 105-2 and N × m WSSs 105-3 and 105-4 will be described. . When a failure of the working path occurs due to an optical fiber cut or the like, the transponders 102-3 and 102-4 that receive the backup path connected to the N × m WSS 105-4 at the OXC at the receiving end are set to 1 × 2 Communication is continued by selecting with the expression selector 104. Similarly, when any of the N × m WSSs 105-3 and 105-4 fails, the transponders 102-3 and 102− connected to the non-failed N × m WSSs 105-3 and 105-4 side are similarly provided. Communication is continued by selecting 4 with the 1 × 2 selector 104.

(Description of the effect of the embodiment of the present invention)
By using N × M WSS11 or M × N WSS12 in OXC1, both port expandability and non-blocking configuration can be achieved. In addition, the N × m WSS 31 and the m × N WSS 32 obtained by dividing the N × M WSS 11 and the M × N WSS 12 into packages are switches in addition to the effects of the N × M WSS and M × N WSS 12 described above. Fault tolerance, switch replacement costs, and port expandability can be improved. Further, if only one of the Add / Drop functions of the N × m WSS 31 and the m × N WSS 32 is realized, it can be realized at a lower cost and simply than the N × m WSS 31 and the m × N WSS 32 described above.

  As mentioned above, although each embodiment of OXC was described, this invention can be variously changed unless it deviates from a summary. For example, the multiplexing member can be provided with a one-output optical combining circuit with N + α inputs. Further, k is 2 or more and α or less.

  In addition to the wavelength selective switch and the optical coupler, the demultiplexing member may be a circuit having a function of separating the input WDM light into a plurality of WDM light / single wavelength light and outputting them. In addition to the wavelength selective switch and the optical coupler, the multiplexing member may be a circuit having a function of combining and outputting a plurality of input WDM light / single wavelength light.

  In addition, as the optical separation circuit, an optical coupler or a circuit having a function of separating and outputting input WDM light into a plurality of WDM light / single wavelength light can be adopted. It is possible to employ a circuit having a function of combining and outputting a plurality of WDM light and single wavelength light.

1 is a diagram showing a basic configuration of an optical cross-connect device according to a first embodiment of the present invention. It is a figure which shows the example of an internal structure of NxM type WSS used for the optical cross-connect apparatus shown in FIG. It is a figure which shows the optical cross-connect apparatus which concerns on 2nd embodiment of this invention, and is a figure which shows the structure which changed a part of 1st embodiment. It is a figure which shows the optical cross-connect apparatus which concerns on 3rd embodiment of this invention, and is a figure which shows the structure which changed a part of 2nd embodiment. It is a figure explaining the example of a port number reduction structure in the NNI switch by the side of Input in the optical cross-connect apparatus which concerns on 2nd embodiment of this invention. It is a figure explaining the example of a port number reduction structure in the NNI switch by the side of Output in the optical cross-connect apparatus which concerns on 2nd embodiment of this invention. It is a figure which shows the internal structural example 1 of Nxm type WSS shown to 2nd, 3rd embodiment. It is a figure which shows the internal structural example 2 of Nxm type WSS shown to 2nd, 3rd embodiment. It is a figure which shows the internal structural example 3 of Nxm type WSS shown to 2nd, 3rd embodiment. It is a figure which shows the implementation example only of the Add function of Nxm type WSS shown in 2nd, 3rd embodiment. It is a figure which shows the implementation example of only the Drop function of Nxm type WSS shown in 2nd, 3rd embodiment. It is a figure which shows an example of the optical network using the optical cross-connect apparatus which concerns on embodiment of this invention. It is a figure which shows the structural example of the optical cross-connect apparatus shown in FIG. It is a figure which shows an example of the optical network by the conventional optical cross-connect apparatus. It is a figure which shows the block configuration of the conventional optical cross-connect apparatus. It is a block block diagram of the conventional highly functional optical cross-connect apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 1A, 1B ... Optical cross-connect apparatus, 11 ... NxM type WSS, 12 ... MxN type WSS, 13-1 to 13-N ... Optical coupler, 14-1 to 14-N ... "N + 1" x 1-type WSS, 31-1 to 31-α ... N × m-type WSS, 32-1 to 32-α ... m × N-type WSS, 33-1 to 33-N ... 1 × “N + 1” -type WSS, 35- 11-35-αm: receiver, 36-11-36-αm ... transmitter, 40, 41, 70 ... 1 × m WSS, 50, 52, 60 ... AWG, 51, 61 ... N × m matrix switch 71 ... Nx1 OC, 72, 91 ... Nx1 SW, 80 ... 1xN SW, 81 ... mx1 OC, 90 ... 1xm OC, 92 ... Tunable Filter,

Claims (12)

Wavelength multiplexed signals are received from N (N ≧ 2) NNI (Network Node Interface) side input paths and α (α ≧ 1) UNI (User Network Interface) side input paths. In an optical cross-connect device that selects a wavelength multiplexed signal output path for each wavelength and transmits wavelength multiplexed signals to N NNI output paths or α UNI output paths.
A demultiplexing member with N 1 inputs and an output of N + α (α ≧ 1);
A N output N + α input and one output combining member;
a first wavelength selective switch having m (m ≧ 2) outputs with k (α ≧ k ≧ 1) N inputs;
a second wavelength selective switch with k (α ≧ k ≧ 1) m (m ≧ 2) inputs and N outputs;
Consists of
Configure at least one of the demultiplexing member and the multiplexing member with a wavelength selective switch,
The demultiplexing member connects the input path on the NNI side to one input port, connects N output ports to the N multiplexing members, and connects the remaining α output ports to the first port. Connected to the wavelength selective switch of
The multiplexing member connects the outputs of the N demultiplexing members to N input ports, connects the outputs of the second wavelength selective switch to the remaining α input ports, and outputs one output port. To the output path on the NNI side,
The first wavelength selective switch connects the output of the demultiplexing member to N input ports, and connects one receiver to each of the m output ports,
It said second wavelength selective switch connects the output of each one of the transmitters to the m input ports, connecting the multiplexing member to N output ports,
The first wavelength selective switch is composed of N 1 × m output wavelength selective switches and m N × 1 output wavelength selective switches for N inputs,
The second wavelength selective switch is composed of m 1 × N output wavelength selective switches and N m × 1 output wavelength selective switches for m inputs. apparatus. Wavelength multiplexed signals are received from N (N ≧ 2) NNI (Network Node Interface) side input paths and α (α ≧ 1) UNI (User Network Interface) side input paths. In an optical cross-connect device that selects a wavelength multiplexed signal output path for each wavelength and transmits wavelength multiplexed signals to N NNI output paths or α UNI output paths.
A demultiplexing member with N 1 inputs and an output of N + α (α ≧ 1);
A N output N + α input and one output combining member;
a first wavelength selective switch having m (m ≧ 2) outputs with k (α ≧ k ≧ 1) N inputs;
a second wavelength selective switch with k (α ≧ k ≧ 1) m (m ≧ 2) inputs and N outputs;
Consists of
Configure at least one of the demultiplexing member and the multiplexing member with a wavelength selective switch,
The branching member connects the input path on the NNI side to one input port, connects the N output ports to the N multiplexing members, and connects the remaining α output ports to the first port. Connected to the wavelength selective switch of
The multiplexing member connects the outputs of the N demultiplexing members to N input ports, connects the outputs of the second wavelength selective switch to the remaining α input ports, and outputs one output port. To the output path on the NNI side,
The first wavelength selective switch connects the output of the demultiplexing member to N input ports, and connects one receiver to each of the m output ports,
It said second wavelength selective switch connects the output of each one of the transmitters to the m input ports, connecting the multiplexing member to N output ports,
The first wavelength selective switch and the second wavelength selective switch include optical demultiplexers corresponding to the number of input ports, optical multiplexers corresponding to the number of output ports, and “number of input ports” corresponding to the number of multiplexed wavelengths. An optical cross-connect device comprising a matrix switch of “number of output ports” . Wavelength multiplexed signals are received from N (N ≧ 2) NNI (Network Node Interface) side input paths and α (α ≧ 1) UNI (User Network Interface) side input paths. In an optical cross-connect device that selects a wavelength multiplexed signal output path for each wavelength and transmits wavelength multiplexed signals to N NNI output paths or α UNI output paths.
A demultiplexing member with N 1 inputs and an output of N + α (α ≧ 1);
A N output N + α input and one output combining member;
a first wavelength selective switch having m (m ≧ 2) outputs with k (α ≧ k ≧ 1) N inputs;
a second wavelength selective switch with k (α ≧ k ≧ 1) m (m ≧ 2) inputs and N outputs;
Consists of
Configure at least one of the demultiplexing member and the multiplexing member with a wavelength selective switch,
The branching member connects the input path on the NNI side to one input port, connects the N output ports to the N multiplexing members, and connects the remaining α output ports to the first port. Connected to the wavelength selective switch of
The multiplexing member connects the outputs of the N demultiplexing members to N input ports, connects the outputs of the second wavelength selective switch to the remaining α input ports, and outputs one output port. To the output path on the NNI side,
The first wavelength selective switch connects the output of the demultiplexing member to N input ports, and connects one receiver to each of the m output ports,
It said second wavelength selective switch connects the output of each one of the transmitters to the m input ports, connecting the multiplexing member to N output ports,
The first wavelength selective switch includes an optical demultiplexer having the number of input ports and a matrix switch of “product of the number of input ports and the number of multiplexed wavelengths × the number of output ports”.
The second wavelength selective switch includes an optical demultiplexer having the number of output ports and a matrix switch of “product of the number of output ports and the number of multiplexed wavelengths × the number of input ports”. Connect device. Wavelength multiplexed signals are received from N (N ≧ 2) NNI (Network Node Interface) side input paths and α (α ≧ 1) UNI (User Network Interface) side input paths. In an optical cross-connect device that selects a wavelength multiplexed signal output path for each wavelength and transmits wavelength multiplexed signals to N NNI output paths or α UNI output paths.
A demultiplexing member with N 1 inputs and an output of N + α (α ≧ 1);
A N output N + α input and one output combining member;
a first wavelength selective switch having m (m ≧ 2) outputs with k (α ≧ k ≧ 1) N inputs;
a second wavelength selective switch with k (α ≧ k ≧ 1) m (m ≧ 2) inputs and N outputs;
Consists of
Configure at least one of the demultiplexing member and the multiplexing member with a wavelength selective switch,
The branching member connects the input path on the NNI side to one input port, connects the N output ports to the N multiplexing members, and connects the remaining α output ports to the first port. Connected to the wavelength selective switch of
The multiplexing member connects the outputs of the N demultiplexing members to N input ports, connects the outputs of the second wavelength selective switch to the remaining α input ports, and outputs one output port. To the output path on the NNI side,
The first wavelength selective switch connects the output of the demultiplexing member to N input ports, and connects one receiver to each of the m output ports,
It said second wavelength selective switch connects the output of each one of the transmitters to the m input ports, connecting the multiplexing member to N output ports,
The first wavelength selective switch includes a wavelength selective switch that outputs one input and outputs the number of output ports, and an optical combiner that outputs the number of output ports.
The second wavelength selective switch is composed of a wavelength selective switch that outputs one output by the number of input ports corresponding to the number of output ports and an optical demultiplexer that corresponds to the number of input ports. Cross-connect device. Wavelength multiplexed signals are received from N (N ≧ 2) NNI (Network Node Interface) side input paths and α (α ≧ 1) UNI (User Network Interface) side input paths. In an optical cross-connect device that selects a wavelength multiplexed signal output path for each wavelength and transmits wavelength multiplexed signals to N NNI output paths or α UNI output paths.
A demultiplexing member with N 1 inputs and an output of N + α (α ≧ 1);
A N output N + α input and one output combining member;
a first wavelength selective switch having m (m ≧ 2) outputs with k (α ≧ k ≧ 1) N inputs;
a second wavelength selective switch with k (α ≧ k ≧ 1) m (m ≧ 2) inputs and N outputs;
Consists of
Configure at least one of the demultiplexing member and the multiplexing member with a wavelength selective switch,
The branching member connects the input path on the NNI side to one input port, connects the N output ports to the N multiplexing members, and connects the remaining α output ports to the first port. Connected to the wavelength selective switch of
The multiplexing member connects the outputs of the N demultiplexing members to N input ports, connects the outputs of the second wavelength selective switch to the remaining α input ports, and outputs one output port. To the output path on the NNI side,
The first wavelength selective switch connects the output of the demultiplexing member to N input ports, and connects one receiver to each of the m output ports,
It said second wavelength selective switch connects the output of each one of the transmitters to the m input ports, connecting the multiplexing member to N output ports,
The second wavelength selective switch is composed of an optical switch that has one input for the number of input ports and outputs for the number of output ports, and an optical combiner that has one input for the number of output ports and one output for the number of output ports. optical cross-connect device, characterized in that that. Wavelength multiplexed signals are received from N (N ≧ 2) NNI (Network Node Interface) side input paths and α (α ≧ 1) UNI (User Network Interface) side input paths. In an optical cross-connect device that selects a wavelength multiplexed signal output path for each wavelength and transmits wavelength multiplexed signals to N NNI output paths or α UNI output paths.
A demultiplexing member with N 1 inputs and an output of N + α (α ≧ 1);
A N output N + α input and one output combining member;
a first wavelength selective switch having m (m ≧ 2) outputs with k (α ≧ k ≧ 1) N inputs;
a second wavelength selective switch with k (α ≧ k ≧ 1) m (m ≧ 2) inputs and N outputs;
Consists of
Configure at least one of the demultiplexing member and the multiplexing member with a wavelength selective switch,
The branching member connects the input path on the NNI side to one input port, connects the N output ports to the N multiplexing members, and connects the remaining α output ports to the first port. Connected to the wavelength selective switch of
The multiplexing member connects the outputs of the N demultiplexing members to N input ports, connects the outputs of the second wavelength selective switch to the remaining α input ports, and outputs one output port. To the output path on the NNI side,
The first wavelength selective switch connects the output of the demultiplexing member to N input ports, and connects one receiver to each of the m output ports,
It said second wavelength selective switch connects the output of each one of the transmitters to the m input ports, connecting the multiplexing member to N output ports,
The first wavelength selective switch includes an optical shunt having one input and the number of output ports corresponding to the number of input ports, an optical switch having one output corresponding to the number of input ports corresponding to the number of output ports, and an output port. An optical cross-connect device comprising a number of wavelength selective filters . The optical cross-connect device according to any one of claims 1 to 6 ,
An optical cross-connect device comprising: an optical branch circuit having one input and an output of N + α in the branching member. The optical cross-connect device according to any one of claims 1 to 6 ,
An optical cross-connect device, wherein the multiplexing member comprises an N + α input and 1-output optical combining circuit. The optical cross-connect device according to any one of claims 1 to 6 ,
The optical cross-connect device, wherein k is 2 or more and α or less. The optical cross-connect device according to any one of claims 1 to 6 ,
The demultiplexing member has one input and N + 1 outputs,
The optical cross-connect device, wherein the demultiplexing member and the first wavelength selective switch are connected by N 1-input and 1 + k output optical couplers. The optical cross-connect device according to any one of claims 1 to 6 ,
The multiplexing member has N + 1 inputs and 1 output,
The optical cross-connect device, wherein the second wavelength selective switch and the multiplexing member are connected by N 1 + k input and one output optical couplers. In the optical network using the optical cross-connect device according to any one of claims 1 to 11,
A working path and a protection path are formed between different optical cross-connect devices, and a working path transmitter and a protection path transmitter are connected to the different second wavelength selective switches, respectively, and a working path receiver and a protection path are connected. An optical network, wherein the first wavelength selective switch is connected to a different receiver.

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