WO2005036782A1

WO2005036782A1 - Extendable wavelength division multiplex transmission device

Info

Publication number: WO2005036782A1
Application number: PCT/JP2003/012830
Authority: WO
Inventors: Nobuyuki Kaji
Original assignee: Allied Telesis K.K.
Priority date: 2003-10-07
Filing date: 2003-10-07
Publication date: 2005-04-21
Also published as: JPWO2005036782A1; AU2003271111A1

Abstract

There is provided a WDM transmission device capable of flexibly coping with the change of the system specification, improving extension and operation characteristics, and achieving effective use of network resources. An uplink module slot (11) is provided in a WDM transmission device main body housing (10). An uplink module selected from a plurality of uplink modules (101, 210) of different transmission distances is detachably attached to the uplink module slot (11). The uplink module (101) has a WDM port (102) and a stacking port (103) and can be connected to the other uplink module (201) by cascade connection.

Description

Description Scalable wavelength division multiplex transmission equipment

The present invention relates to a wavelength division multiplexing (WDM) transmission device that enables long-distance and high-speed transmission by wavelength-multiplexing a plurality of channels, and in particular, relates to a plurality of low-power ports and at least one remote port. And a WDM transmission device having: Background art

In recent years, various WDM transmission devices have been provided which enable long-distance transmission by wavelength-multiplexing a plurality of gigabit Ethernets (Ethernet is a registered trademark, the same applies hereinafter) to single-mode optical fibers. For example, there is a WDM transmission device currently on the market that is capable of transmitting a maximum of 20 Gbps / two cores (Full Duplex) by connecting eight gigabit Ethernets. Such WDM transmission devices are indispensable communication devices such as wide area LAN (local-area network) and Ρ Ρ (fiber-to-the-home) for building a broadband network in the future.

Japanese Patent Application Laid-Open No. 2000-324050 (hereinafter referred to as Patent Document 1) has a plurality of local modules, at least one remote module, and one management module. WDM transmission equipment to be incorporated into one cage is described. The general-purpose module can support various media such as ATM, FDDI, Ethernet (registered trademark), etc. (paragraphs 0003, 0014, Figures 1 and 2).

Japanese Patent Application Laid-Open No. 11-095060 (hereinafter referred to as Patent Document 2) discloses an optical WD. A cascaded optical multiplexing device is disclosed as an example of the M transmission device. In this conventional WDM transmission device, all channels are separated and multiplexed by connecting the optical blocks capable of wavelength separation and multiplexing with each other in a power-scale manner. For example, when 8-channel WDM light enters a remote port, one optical block sequentially separates channels 1 to 4 of the 8-channel WDM light and cascade-connects the remaining channels 5 to 8. Another optical block is similarly separated. Conversely, eight-channel optical signals are sequentially multiplexed through these optical blocks and sent out from the remote port as wavelength-division multiplexed light (paragraphs 024-27, Figures 1, 8, and 9).

However, the WDM transmission device of Patent Document 1 describes increasing the number of remote modules, but does not mention changing the transmission distance of WDM. Changes in the transmission distance often occur due to changes in the installation location or in-house circumstances, and the ability to easily change the transmission distance is extremely important in practical use.

In general, the structure of a WDM transmission device is such that a number of slots are provided in the vertical direction on the front or rear surface of the housing of the WDM transmission device, and necessary modules are mounted therein. However, Patent Document 1 does not disclose a specific cage configuration incorporating a general-purpose module. Further, in the cage configuration of Patent Document 1, it is necessary to prepare a number of slots in one housing, and if local ports are used in a number corresponding to the number of slots, resources of the WDM network can be effectively used. It can be used, but cannot be fully used in small networks.

Similarly, the WDM transmission device disclosed in Patent Document 2 accommodates four or eight channels in one device housing. Therefore, if the same number of LANs are connected, resources can be used effectively, but only one or two LANs will be connected depending on the scale, installation location, or internal circumstances of the LAN. There is also a case.

If there are local ports that are not connected in this way, the characteristics of WDM such as high-speed large-capacity transmission cannot be fully utilized. Conversely, if it was initially thought that a 4-channel WDM transmission device would be sufficient, but the situation changed and required 6 channels, in this example, a new 8-channel WDM transmission device was purchased and replaced There is a need. The necessity of replacing such a transmission device impairs the flexibility as a WDM transmission system, not only increases costs, but also wastes resources because two out of eight channels are not used. I will. Also in the WDM transmission device described in Patent Document 2, it is assumed that optical blocks are cascaded in one housing to perform channel separation and multiplexing, and the same problem occurs.

Therefore, an object of the present invention is to provide a WDM transmission device that can flexibly respond to changes in system specifications.

Another object of the present invention is to provide a WDM transmission device that can easily expand a system and achieve effective use of network resources. Disclosure of the invention

According to a first aspect of the present invention, there is provided a wavelength division multiplexing / demultiplexing apparatus having a plurality of local ports and at least one remote port, comprising: a housing having at least a remote module slot; and a remote port having a different transmission distance. And a plurality of remote modules, wherein one remote module selected from the plurality of remote module modules is detachably attached to the remote module slot.

At least one of the plurality of remote modules is optically connected to the remote port, performs multiplexing and demultiplexing of light of a predetermined wavelength, and optical multiplexing / demultiplexing means for passing signal light of another wavelength. Optically connected to the optical multiplexing / demultiplexing means; And a stacking port for emitting the signal light having passed through the demultiplexing means to the outside and receiving the signal light from the outside.

The housing may further include a management module slot, and the internal state of the wavelength division multiplexing / demultiplexing transmission device may be remotely monitored by a management module installed in the management module slot.

According to a second aspect of the present invention, in a system including at least a first wavelength division multiplexing transmission device and a second wavelength division multiplexing transmission device,

The first wavelength division multiplexing / demultiplexing apparatus includes: a first remote module selected from a plurality of remote modules having remote ports having different transmission distances; a first remote module slot for detachably mounting the first remote module; Wherein the first remote module is optically connected to a remote port of the first remote module, performs multiplexing and demultiplexing of light of the first wavelength group, and performs the multiplexing and demultiplexing of light of the first wavelength group. A first optical multiplexing / demultiplexing means for transmitting light of two wavelength groups, and optically connected to the first optical multiplexing / demultiplexing means, emitting a signal light having passed through the first optical multiplexing / demultiplexing means, A first stacking port for receiving the signal light; and

The second wavelength division multiplexing / demultiplexing apparatus includes: a second remote module selected from the plurality of remote modules; and a second remote module slot for detachably mounting the second remote module. A remote module having second optical multiplexing / demultiplexing means for optically connecting to a remote port of the second remote module and multiplexing and demultiplexing the light of the second wavelength group;

The first wavelength division multiplexing transmission device and the second wavelength division multiplexing transmission device are accommodated in one unit, and the first stacking port of the first wavelength division multiplexing transmission device and the second wavelength division multiplexing transmission device The second remote port is optically connected by an optical cable.

The first wavelength division multiplexing / demultiplexing transmission device is a cable 1 attached to a management module slot. Further comprising a management module, wherein the second wavelength division multiplexing / demultiplexing apparatus further comprises a second management module attached to a management module slot, and the first and second management modules are connected to each other. It is desirable that the internal states of the first wavelength division multiplexer / demultiplexer and the second wavelength division multiplexer / demultiplexer be remotely monitored. As described above, according to the present invention, a required transmission distance is required because one remote module selected from a plurality of remote modules having different transmission distances is detachably attached to the remote module slot of the housing. The most suitable remote module can be selected and arrived, and it can easily respond to changes in transmission distance.

Furthermore, since the remote module is provided with a stacking port optically connected to the remote port, another WDM transmission device can be cascaded and the number of local ports accommodated can be easily expanded. it can. Furthermore, it is also possible to connect the remote port and the stacking port to separate WDM transmission devices, thereby greatly improving the expandability and flexibility of the system configuration. Brief Description of Drawings

FIG. 1 is a perspective view showing a schematic configuration and functions of a WDM transmission device according to an embodiment of the present invention.

FIG. 2 is a perspective view of a WDM transmission device system in which two WDM transmission devices according to the present embodiment are unitized.

FIG. 3 is a perspective view of a WDM transmission device system in which two WDM transmission devices according to the present embodiment are cascaded.

FIG. 4 is a schematic block diagram showing an internal circuit of the WDM transmission device system shown in FIG.

Fig. 5 is a front view showing a WDM transmission system in which two units of Fig. 2 are stacked. It is.

FIG. 6 is a diagram showing a connection form of the two-stage WDM transmission device system shown in FIG. FIG. 7A is a schematic system configuration diagram for explaining a loop pack test operation when a system using the WDM transmission device according to the present embodiment is constructed. FIG. 7B is a schematic system configuration diagram for explaining a loopback test operation from the SNMP manager.

FIG. 8A is a configuration diagram of a WDM transmission system for explaining a missing link function when a local port is disconnected.

FIG. 8B is a configuration diagram of the WDM transmission system for explaining the missing link function when the remote port is disconnected.

FIG. 9 is a network configuration diagram showing an example of a WDM transmission network using the WDM transmission device according to the present invention.

FIG. 10 is a network configuration diagram showing another example of the WDM transmission network using the WDM transmission device according to the present invention. BEST MODE FOR CARRYING OUT THE INVENTION

In FIG. 1, the main body housing 10 of the WDM transmission apparatus according to the present embodiment has a rectangular parallelepiped shape having a thickness of 1 U (approximately 44 mm), and one uplink module slot 11 1 and 1 management A module slot 12 and a plurality of local port slots 13 are provided.

Uplink module 101 or uplink module 201 prepared in advance can be installed in uplink module slot 11. As will be described later, the uplink module 101 has a WDM port 102 as a remote port (RP) and a stacking port (SP) 103 for cascade connection. 3 can be used to cascade other WDM transmission equipment. Uplink module 201 has a WDM port. G 202 and no stacking port. The user may select the uplink module 101 when expansion is required due to the power cascade connection, and may select the uplink module 201 when expansion is not required. As the uplink module 101 and the uplink module 201, modules having different transmission distances are prepared. Here, uplink modules 201.1, 201.2 and 201.3 with transmission distances of 50 km, 80 km and 120 km respectively are shown. The user can select the uplink module with the transmission distance most suitable for the distance to the partner WDM transmission device.

A management module 104 or a management module 203 prepared in advance can be selectively installed in the management module slot 12. The management modules 104 and 203 according to the present embodiment can be realized by a simple network management protocol (SNMP) management module. The management console 104 is provided with an SNMP connection port 105 and stacking ports 106 and 109 for SNMP. The SNMP connection port 105 is connected to an SNMP manager via a network such as Ethernet, for example, and can remotely monitor the link status and power status of the WDM transmission device. The management module 203 is provided with an SNMP connection port 204 and an SNMP stacking port 205.

Further, in the present embodiment, two local port slots 13 are provided, each of which is equipped with an optical transceiver module corresponding to a GBIC (Gigabit Interface Converter).

FIG. 2 is a perspective view of a WDM transmission device system in which two WDM transmission devices according to the present embodiment are unitized. Here, the uplink module 101 and the management module 104 are attached to the WDM transmission device 1, and the uplink module 201 and the management module 203 are attached to the WDM transmission device 2. It is assumed that

As shown in FIG. 2, WDM transmission apparatuses 1 and 2 are housed side by side with each other in a 1U-thick cut frame 20. The compact 1U size makes it possible to mount it on a 19-inch rack. Further, the WDM transmission apparatuses 1 and 2 can be cascaded as described below to function as one WDM transmission apparatus. Therefore, it is significant that the WDM transmission apparatuses 1 and 2 are housed in the unit frame 20 to form one unit as shown in FIG.

In FIG. 3, the WDM transmission device 1 according to the present embodiment can cascade-connect another WDM transmission device 2 to function as one WDM transmission device.

Each of the WDM transmission device 1 and the WDM transmission device 2 has a module configuration as shown in FIG. 1, and here, as shown in FIG. 2, the WDM transmission device 1 includes an uplink module 101 and a management module. It is assumed that 104 is attached, and the uplink module 201 and the management module 203 are attached to the WDM transmission device 2.

In the WDM transmission device 1, the uplink module 101 has a WDM port 102 as a remote port (RP) and a stacking port (SP) 103 for cascade connection. The management module 104 is an SMP management module, and has an SMP connection port 105 and stacking ports 106 and 109 for SNMP. The SNMP connection port 105 is connected to an SNMP manager via a network such as Ethernet, for example, and can remotely monitor the link state and power state of the WDM transmission device 1. Further, the WDM transmission device 1 has two local ports 107 and 108, each of which comprises an optical transceiver module compatible with GBIC.

In the WDM transmission device 2, the uplink module 201 has a WDM port 202 which is a remote port (RP). The management module 203 is an SN MP management module, and the S NMP connection port 204 and stacking It has port 205. Furthermore, the WDM transmission device 2 is also provided with two local ports 206 and 207, each of which is composed of an optical transceiver module compatible with GBIC.

According to the present embodiment, the WDM port 102 of the WDM transmission device 1 is connected to the single mode optical fiber cable 301, and the stacking port 103 is connected to the WDM port 202 of the WDM transmission device 2. Are connected through an optical fiber cable 302. Further, the SNMP stacking port 106 of the management module 104 is connected to the SNMP connection port 204 of the WDM transmission device 2 through an optical fiber cable 303.

By cascading in this way, the uplink module 101 and the uplink module 201 function as one uplink module, and the management module 104 and the management module 203 also connect to the WDM transmission device 1. It functions as one management module that manages option 2. Therefore, by simply cascading a WDM transmission device 2 containing two GBIC ports to a WDM transmission device 1 containing two GBIC ports, it can be upgraded to a WDM transmission device containing four GBIC ports. can do.

Although not shown in FIG. 3, each of WDM transmission apparatuses 1 and 2 is provided with a link test button for activating a loopback test. FIG. 4 is a schematic block diagram showing an internal circuit of the WDM transmission device system shown in FIG. The components described in FIG. 3 are denoted by the same reference numerals.

In FIG. 4, the uplink module 101 of the WDM transmission device 1 has multiplexers / demultiplexers 110 and 111. The multiplexer / demultiplexer ₁₁₀ separates the optical signal of the specific wavelength ( _Lr11 ) from the wavelength multiplexed light received through the WDM port ₁₀₂ , reflects the other wavelength light, and also outputs the specific wavelength (; _iT11 ) is multiplexed and transmitted to the WDM port 102. Similarly, the multiplexer / demultiplexer 1 1 1 passed through the multiplexer / demultiplexer 1 110 Shines anti other wavelength light as well as separating the optical signal of a specific wavelength (L _r12) from the wavelength multiplexed light, and also sent to the WDM port 102 multiplexes transmission light of a specific wavelength _(λ τ12). The wavelength division multiplexed light that has passed through the multiplexers / demultiplexers 110 and 111 is sent to another WDM transmission device 2 through the stacking port 103 and the optical cable 302. The received light separated by the multiplexer / demultiplexer 110 is transferred to the low-power port 107 through the physical layer device 112. Transmitted light received at the local port 107 from the gigabit LAN is multiplexed by the multiplexer / demultiplexer 110 through the physical layer device 112 and transmitted from the WDM port 102. Similarly, the received light separated by the multiplexer / demultiplexer 111 is transferred to the local port 108 through the physical layer device 112. The transmission light received at the local port 108 is multiplexed by the multiplexer / demultiplexer 111 through the physical layer depth 113 and transmitted from the WDM port 102.

Further, the WDM transmission apparatus 1 is provided with a control unit 114, a link test button 115, and an LED (light emitting diode) 116 as an indicator. The control unit 114 controls the physical layer devices 112 and 113, In accordance with the instruction from the management module 104, necessary information (link status, power status, etc.) is collected and returned to the management module 104. As described later, the link test button 115 is provided for performing a link test when a WDM communication system is constructed.

The uplink module 201 of the WDM transmission device 2 has the same configuration as the uplink module 101 except that the transmission / reception wavelength is different and the stacking port 103 is not provided. Further, the same physical layer devices 210 and 211 as the WDM transmission device 1 and local ports 206 and 207 are provided. Further, in the WDM transmission apparatus 2, similarly, a control unit 212, a link test button 213, and an LED 214 as an indicator are provided, and the control unit 212 controls the physical layer devices 210 and 211, and Information (link status, power status, etc.) required according to the instruction And returns it to the management module 203.

The management module 104 mounted on the WDM transmission device 1 is connected to the management module 203 of the WDM transmission device 2 via a cable 303, and further connected to an SNMP manager via a network. The SNMP manager can monitor the status of WDM transmission devices 1 and 2 through the network.

As a specific example, the up-link module 101, reception wavelength; L _R11 = 129 0 nm, the transmission wavelength _λ τ11 = 1310 nm, the reception wavelength example _R12 = 1330 nm, the transmission wave length; is L _T12 = 1350 nm. In the uplink module 201, the reception wavelength λ _κ11 = 1510 nm, the transmission wavelength; L _T11 = 1530 nm, the reception wavelength; L _R12 = 1570 nra, and the transmission wavelength; l _T12 = l 550 nm. Also, as the uplink modules 101 and 201, required modules can be selected from modules having different transmission distances (for example, 50 km, 80 km, 120 km, etc.).

FIG. 5 is a front view showing a WDM transmission device system in which two units of FIG. 2 are stacked, and FIG. 6 is a diagram showing a connection form of the two-stage WDM transmission device system. Here, four WDM transmission devices 1, 2, 3 and 4 are used. WDM transmission devices 1 and 2 are cascaded by an optical cable 302 as shown in FIG. 3, and WDM transmission devices 3 and 4 are also used. Similarly, they are cascaded. That is, the stacking port 103.3 of the WDM transmission device 3 and the WDM port 202.4 of the WDM transmission device 4 are connected by the optical cable 302.3.

In addition, the SNMP stacking port 106 of the management module 104 is connected to the SNMP connection port 204 of the WDM transmission device 2 through the cable 303, and similarly, the SNMP stacking port 106.3 of the WDM transmission device 3 is connected to the SNMP stacking port 106.3. It is connected to the SNMP connection port 204.4 of the WDM transmission device 4 through Cape 3033. Further, the SNMP connection port 105.3 of the WDM transmission apparatus 3 is connected to the SNMP stacking port 109 of the WDM transmission apparatus 1 by a cable 305. Connected through.

With such a connection, as described above, the uplink modules 101 and 201 function as one uplink module, and similarly, the uplink modules 101. 3 and 210. Also function as one uplink module. Further, the management modules 104, 203, 104. 3, and 204. 34 can also function as management modules for managing the WDM transmission devices 1 to 4, respectively. Therefore, the SNMP manager can monitor the status of the WDM transmission devices 1-4 through the network. In this way, by connecting four WDM transmission devices accommodating two GBIC ports, it is possible to upgrade to a WDM transmission device accommodating eight GBIC ports.

(Link test function)

FIG. 7A is a schematic system configuration diagram for explaining a loop-back test operation when a system using the WDM transmission device according to the present embodiment is constructed, and FIG. 7B is a loop-back test operation from the SNMP manager. FIG. 2 is a schematic system configuration diagram for explaining a test operation.

In the WDM transmission system shown in FIG. 7A, the WDM transmission device 401 according to the present embodiment is connected to the WDM transmission device 402 through an optical fiber cable 403. The WDM transmission device 401 in this example may have the link test button in the present embodiment, and may be either the WDM transmission device 1 or the WDM transmission device 2 in FIG. The configuration shall be as follows.

First, when the optical fiber cable 403 is connected to the WDM port of the WDM transmission device 401 and the system connection is completed, the system builder presses the link test button 115 of the WDM transmission device 401. When detecting that the link test button 1 15 has been pressed, the control unit 1 1 4 sends the physical layer device 1 1 2 or 1 13 is controlled to generate an optical signal of a predetermined wavelength for a link test. The generated test signal is sent from the WDM port 102 of the uplink module 101 to the optical fibercapsule 03 and reaches the partner WDM transmission device 402 as long as the cable 400 is normal. . The received test signal is looped back by the physical layer device of the WDM transmission device 402 and returns to the original WDM transmission device 401. When the returned test signal is received by the physical layer device 112, the control unit 114 turns on the LED indicator indicating the link, and notifies the installer that the link is normal. In this way, the link can be checked for normality when the system is installed. '

In the WDM transmission system shown in FIG. 7B, the WDM ports of the WDM transmission devices 1 and 2 shown in FIGS. 3 and 4 are separately connected to optical fiber cables 404 and 405, respectively, and the management module 104 And 203 are connected by Cape Norre 303. The SNMP manager 407 controls the management modules 104 and 203 of the WDM transmission devices 1 and 2 via the switch 406, and performs the above-described loopback test on the optical fiber cables 404 and Each of them is performed through 405. In this way, after the system operates, a loopback test can be performed by the SNMP manager 407 to periodically monitor the link status.

(Mixing ring function)

Fig. 8A is a block diagram of the WDM transmission system for explaining the mixing link function when the local port is disconnected, and Fig. 8B is for explaining the missing link function when the remote port is disconnected. 1 is a configuration diagram of the WDM transmission system of FIG.

In FIG. 8A, when the local port LP 2 of the WDM transmission device 401 communicates with the local port LP 3 of the WDM transmission device 402, the transmission line of the local port LP 2 is disconnected. I do. Supports local port LP 2 When detecting the disconnection of the transmission line of the local port LP2, the physical layer device P HY disconnects the link of the corresponding WDM transmission wavelength. Thereby, the physical layer device P HY of the WDM transmission device 402 that has received the optical signal of the corresponding transmission wavelength disables the output of the corresponding local port LP 3. In this way, the receiving side can know the occurrence of the link disconnection on the transmitting side.

In FIG. 8B, when the optical fiber cable between the WDM transmission device 401 and the WDM transmission device 402 is cut, as described above, the WDM transmission device 401 and the WDM transmission device 402 The physical layer device P HY corresponding to each local port activates the mixing link function, and disables / outputs the corresponding local port.

(Example of network connection)

FIG. 9 is a network configuration diagram showing an example of a WDM transmission network using the WDM transmission device according to the present invention. Here, of the WDM transmission devices 601 to 604, the WDM transmission devices 601 and 602 are under common management, and the remote port (RP) of the WDM transmission device 601 is The remote port of WDM transmission device 603 is connected by an optical fiber cable, and the remote port (RP) of WDM transmission device 602 is connected to the remote port of WDM transmission device 604 by an optical fiber cable. .

The WDM transmission devices 600 and 602 have the WDM ports of the WDM transmission devices 1 and 2 shown in FIGS. 3 and 4, respectively, connected separately to optical fiber cables, and the management modules 104 and 2 03 is connected by Cape Norre 03. That is, the management modules of the WDM transmission apparatuses 61 and 62 are controlled via the layer 3 switch.

FIG. 10 is a network configuration diagram showing another example of a WDM transmission network using the WDM transmission device according to the present invention. Here, of the WDM transmission devices 701 to 704, the WDM transmission devices 701 and 702 are the WDM transmission devices shown in FIGS. 3 and 4. Cascaded as in transmission devices 1 and 2. That is, the remote port PR of the WDM transmitter 702 is connected to the stacking port SP of the WDM transmitter 701, and the management modules 104 and 203 are connected by the cable 303 to the layer. Managed through three switches. The WDM transmission device 703 has the same configuration as the WDM transmission device 1 in FIGS. 3 and 4, and the remote port (RP) of the WDM transmission device 701 is connected to the remote port of the WDM transmission device 703. Connected by fiber cable. Further, a stacking port (SP) of the WDM transmission device 703 is connected to a remote port of the WDM transmission device 704 by an optical fiber cable.

As described above, the WDM transmission apparatus according to the present embodiment has a stacking port that enables a stack connection in addition to the remote port, so that the local WDM transmission apparatus can be easily connected to another WDM transmission apparatus by cascading. The number of ports accommodated can be expanded. Furthermore, it is possible to connect the remote port and the stacking port to separate WDM transmission devices, respectively, and it is possible to greatly improve the expandability and flexibility of the system configuration.

Claims

The scope of the claims

1. A wavelength division multiplexing / demultiplexing apparatus having a plurality of local ports and at least one remote port,

A housing having at least a remote module slot;

And a plurality of remote modules having remote ports having different transmission distances, wherein one remote module selected from the plurality of remote modules is detachably attached to the remote module slot. Wavelength division multiplexing transmission equipment.

2. At least one of the plurality of remote modules includes:

Optically connected to the remote port, performs multiplexing and demultiplexing of light of a predetermined wavelength, and optical multiplexing / demultiplexing means for passing signal light of other wavelengths;

A stacking port that is optically connected to the optical multiplexing / demultiplexing means, emits signal light that has passed through the optical multiplexing / demultiplexing means, and receives signal light from outside. Item 2. The wavelength division multiplexing / demultiplexing transmission device according to item 1.

3. At least one of the plurality of remote modules includes:

2. The wavelength division multiplexing transmission apparatus according to claim 1, comprising:

4. The housing according to claim 1, wherein the housing further has a management module slot, and an internal state of the wavelength division multiplexing / demultiplexing transmission device is remotely monitored by a management module installed in the management module slot. Wavelength multiplexing / demultiplexing transmission equipment.

5. In a system including at least the first wavelength division multiplexing transmission device and the second wavelength division multiplexing transmission device,

The first wavelength division multiplexing transmission device, A first remote module selected from a plurality of remote modules having remote ports having different transmission distances, and a first remote module slot for detachably mounting the first remote module, wherein the first remote module is provided.

A first port that optically connects to a remote port of the first remote module, multiplexes and demultiplexes light of a first wavelength group, and transmits light of a second wavelength group other than the first wavelength group; Optical multiplexing / demultiplexing means;

A first stacking port that is optically connected to the first optical multiplexing / demultiplexing means, emits signal light that has passed through the first optical multiplexing / demultiplexing means, and receives signal light from outside;

Has,

The second wavelength division multiplexing / demultiplexing device,

Wherein a plurality of second remote module is selected from the remote module. The _second and a second remote module slot to attach the remote module detachably, and said second remote module remote of the second remote module A second optical multiplexing / demultiplexing means optically connected to a port for multiplexing / demultiplexing the light of the second wavelength group;

The first wavelength division multiplexing transmission device and the second wavelength division multiplexing transmission device are accommodated in one unit, and the first stacking port of the first wavelength division multiplexing transmission device and the second wavelength division multiplexing transmission device A wavelength multiplexing / demultiplexing transmission system, wherein the second remote port is optically connected by an optical cable.

6. The first WDM device further includes a first management module installed in a management module slot, and the second WDM device further includes a second management module installed in a management module slot. Have

By connecting the first and second management modules, the first wavelength division multiplexing The wavelength division multiplexing / demultiplexing transmission system according to claim 5, wherein the internal states of the remote transmission device and the second wavelength division multiplexing / demultiplexing transmission device are remotely monitored.