JP4287496B2 - Terminal relay device and relay method - Google Patents

Description

  The present invention relates to a terminal relay device of a network.

  SONET (Synchronous Optical NETwork) / SDH (Synchronuos Digital Hierarchy) is known as an international standard for high-speed digital communication systems using optical fibers, and is used for an Internet backbone line connecting Internet service providers. SONET / SDH provides optical transmission level communication services such as OC-N: OC-192 / OC-48 / OC-12. Here, OC-N is a SONET standard that designates a transmission level that is an integral multiple (N times) of OC-1 (51.84 Mb / s). The term SONET is mainly used in North America. On the other hand, the standard in Japan, Europe, etc. corresponding to SONET is SDH. Both are called as SONET / SDH.

  As network applications on SONET / SDH, terminal configuration, linear ADM (Add Drop Multiplex) configuration, UPSR (Uni-directional Path Switched Ring) configuration, 2F-BLSR (Bi-directional Line Switched Ring) configuration, 4F-BLSR Examples include the configuration.

  FIG. 1 shows a network with a terminal configuration. As shown in FIG. 1, in the terminal configuration, a terminal relay device (also referred to as an ADX device) is connected point-to-point. In this configuration, the terminal relay device supports a line redundancy function by APS (Automatic Protection Switch) such as 1 + 1 (line configuration of the active transmission line 1 and the standby transmission line 1).

  In this configuration, an interface card called an OC-N card is mounted in a slot on the SONET / SDH side (hereinafter referred to as a high-order group side) of each terminal relay device. The OC-N card is an interface that supports the transmission level of the OC-N (for example, OC-48).

As shown in FIG. 1, in the terminal configuration, one OC-N card is used for each of the working system (Working traffic) and the protection system (Protection Traffic). Two optical fibers F1 and F2 are connected to the active system for transmission and reception. Similarly, two optical fibers F3 and F4 are connected to the standby system for transmission and reception.

This OC-N card is connected to a lower network (hereinafter referred to as a low-order group) connected to SONET / SDH via a cross-connect processing circuit (XC card) and a line switch (Line SW) or a line bridge (Line BR). Connected to the interface card (INF Card). In this case, the transmission path from the low-order group to the SONET / SDH is referred to as an insertion (add) direction transmission path. A transmission path from the SONET / SDH to the low-order group is called a transmission path in the drop direction.

Furthermore, in the terminal configuration, signals from the low-order group are transmitted from both the working system (Working traffic) and the protection system (Protection Traffic) through the line bridge 300, for example. On the other hand, the signals received from both the transmission line of the working system (Working traffic) and the protection system (Protection Traffic), for example, by the line switch 301,
The signal of the transmission line with the better transmission quality is selected.

FIG. 2 shows a network based on the Linear ADM configuration. In the Linear ADM configuration, three or more terminal relay devices (ADX devices) are connected in a line. FIG. 2 shows details of a terminal relay device (ADX device) located at an intermediate (relay) station on the link. Also in the Linear ADM configuration, the terminal relay device performs route setting by the insertion (add) / drop function in the device and achieves line redundancy similar to FIG.

  FIG. 3 shows a network with a UPSR configuration. As shown in FIG. 3, in the UPSR configuration, the terminal relay device is connected to a ring network including two systems of optical fibers F1, F2-F3, and F4. In such a ring-shaped network, an interface located on the left side when viewed from one terminal relay device among the above two systems is called, for example, an east side (east side, East) interface. An interface located on the right side when viewed from one terminal relay device is referred to as a west (west) interface. However, the names of the east side and the west side are merely convenient names for identifying the connection direction, and are not directly related to the actual geographical direction.

  In the example of FIG. 3, fibers F1 and F2 are connected to the OC-N card on the east side. In addition, a clockwise signal is transmitted to the fiber F1. Further, a counterclockwise signal is received from the fiber F2.

  Similarly, fibers F3 and F4 are connected to the OC-N card on the west side. Further, a counterclockwise signal is transmitted to the fiber F3. Further, a clockwise signal is received from the fiber F4.

  When the high-speed line (OC-N) as shown in FIG. 3 has a UPSR configuration, the signal channel assigned to communication between each node (terminal relay device) on the system (ring network) is, for example, STS-1 Alternatively, transmission capacity called OC-1 or the like is used as a unit, and for example, a line capacity for N channels is configured as a whole.

  For example, a low-order group side line (Tributary line) is set in the direction of the high-order group side line (OC-N UPSR) on a card that handles TSI (Time Space Interchange) and various protection switching processes in the apparatus. That is, the low-order group side line is assigned to the corresponding line from among the lines for STS-1 × N channels on the UPSR network. This allocation process is called an insertion process.

  At the time of this insertion processing, the bridge 300 allocates the signal on the same line to both the east side and the west side, so that the signal on the line is transmitted on the ring network through different paths, thereby realizing a redundant configuration.

  On the other hand, in the signal receiving side node (terminal relay device), the line is set in the reverse direction (higher order group side line → lower order group side line). In this case, the east and west channels of the higher order group are extracted and assigned on the lower order group side line.

  That is, the east-side and west-side line signals to be terminated on the high-order group side line are extracted. Then, the path switch 301 selects a line with better line quality at the path level from the detection status of the line alarm or the like.

  On the other hand, when a transmission line (line) is disconnected, etc., relief in units of lines is called line protection. A switch that is used for line protection and switches between the active system and the standby system in units of lines is called a line switch.

  A component that branches a signal into a working system and a standby system in units of lines is called a line bridge.

  FIG. 4 shows a network with a 2F-BLSR configuration. As shown in FIG. 4, even in the 2F-BLSR configuration, the terminal relay device is connected to a ring network including two optical fibers F1, F2-F3, and F4, as in the UPSR configuration.

  However, in a network having a BLSR configuration, the terminal relay device (ADX device) does not transmit the same signal in two directions on the east side and the west side during transmission. When a failure occurs in such a ring configuration with two systems (two lines) of optical fiber, loopback (Bridge) control is performed on a line-by-line basis using the OH (Over Head) byte of the APS (Automatic Protection Switch) protocol. Execute, and transfer the signal of the working channel (Working channel) to the protection channel. Thereby, the line is relieved in the BLSR configuration network.

  FIG. 5 shows a network with a 4F-BLSR configuration. In the 4F-BLSR configuration, the terminal relay device is connected to a ring network using four systems (four lines) of optical fibers. In the 4F-BLSR configuration, the terminal relay device uses a 4-fiber ring configuration to perform line rescue in 1 + 1 line protection and loopback operation in units of lines using the OH byte of the APS protocol when both the working line and protection line are disconnected. Perform line relief.

  These terminal relay devices have the main function of line setting (TSI) on the network. The line setting refers to a through / add / drop process according to a line unit mapped on the OC-N signal frame. This terminal relay device uses functions corresponding to the various applications as described above, and one device is shared by a plurality of applications.

  FIG. 5 is an example of a network in which a high-order group side line (OC-N) is configured by 4F-BLSR. As described above, the 4F-BLSR uses both the 2F-BLSR configuration in which half of the normal time line is a working line and the other half is a protection line and the 1 + 1 line protection / BLSR line relief.

  The terminal relay device as described above has an interface card (referred to as an OC-N card) corresponding to the transmission level of the corresponding network (OC-N) corresponding to various network applications. The terminal relay device has a line setting (cross-connect) card having various protection switching functions as a main component.

  FIG. 6 shows a configuration example of a terminal relay device that implements a plurality of protection functions. In FIG. 6, the interface cards (INFCard # 1 to #n) are OC-N interface functional units corresponding to various transmission levels on the high-order group side, or interface functional units to the low-order group side line.

  These interface cards are for the purpose of OC / N transmission frame generation / termination function, working line (Work) / protection line (Protect) in 1 + 1 redundant configuration, or east / west transmission unit in ring configuration, Used as an add / drop unit as a low-order group.

System blocks (Sys # 1 to #m) provided before and after the cross-connect processing unit (XC) perform protection line switching corresponding to various network applications by line setting. For example, the system block realizes line switching processing according to the APS protocol for the transmission line (line) in the 1 + 1 redundant configuration with respect to the OC-N level transmission line. Furthermore, the system block and the cross-connect processing unit construct a system that can handle various applications by using a line setting (add / drop / through) function.

  However, the configuration of the terminal relay device shown in the conventional example has a fixed arrangement configuration with respect to the interface card to which the various protection line switching processing circuits and the cross-connect processing units correspond.

  Further, conventionally, a line protection switching circuit for switching between the active / standby system in units of lines and a path protection switching circuit for switching between the active / standby systems in units of channels have been shared as selector circuits.

  Conventionally, there has been a series of switching circuits such as line / path protection. For example, in the configuration of FIG. 6, a system block 310 that executes Line APS processing and a system block 311 that executes BLSR processing are connected in series.

  In this configuration, when the Line APS process is executed, the system block 311 that executes the BLSR process is set to through. In addition, when executing the BLSR process, the system block 310 that executes the Line APS process is set to through.

Thus, conventionally, a configuration in which the switching circuit is shared by a plurality of functions, or a configuration in which a plurality of switching circuits are connected in series, one of them is used and the other is set to through has been adopted. In such a configuration, once the operation is started, since one switching circuit is shared by a plurality of functions, there is a problem that the switching circuit cannot be changed independently of other functions. Further, there has been a problem that there is a limitation on the accommodation position (Slot) of the interface card connected to the switching circuit and the upgrade method / function.
JP 11-313096 A

  That is, in the apparatus having the cross-connect processing circuit in the prior art, the interface to various protection switching functions required in addition to the line setting has a fixed connection relationship with the slot of the corresponding interface card. For this reason, there is a restriction on the accommodation position (slot) of the interface card in the device, so it is necessary to disconnect the line or reconfigure the line when reconfiguring the system (including in-service upgrade) such as adding or replacing the interface card. It became. Therefore, there is a problem that it is difficult to achieve both such system reconfiguration and provision of sufficient services to customers.

  In addition, on the BLSR network, a protection line pass-through is executed as a working line relief operation in the event of a line failure between nodes. That is, the terminal relay device connected to the link in which the failure has occurred loops back the channel to the link in the reverse direction to the link direction, and rescues the line by the reverse ring.

  At the time of this pass-through, the line (channel) when the line is normal and the line (channel) when the through is set are fixed as the same channel. This is because if the change of the channel, that is, the time slot is allowed at the time of pass-through, it becomes impossible to recognize which channel the normal channel corresponds to by the relief operation. However, such a fixed time slot allocation process has caused a problem that the line efficiency on the network cannot be increased.

  Furthermore, there is an increasing demand for improving the processing capability of the cross-connect processing circuit in a transmission apparatus that is compatible with various network applications as described above and that aims to be compact. Among them, the load due to the signal capacity for various protection switching circuits including the cross connection processing of the main signal is very large.

  The present invention has been made in view of such problems of the conventional technology. That is, an object of the present invention is to flexibly execute a system reconfiguration of a network including a terminal relay device or switch between a working line and a protection line and provide sufficient services and functions to customers.

  In order to solve the above problems, the present invention employs the following means. That is, the present invention provides such a cross-connect processing circuit for executing cross-connect processing including line setting on the network, and a line on the input side of the cross-connect processing circuit. A plurality of such first transmission line switching units for switching between the active transmission line and a standby transmission line that is an alternative transmission line to the active transmission line, and the network on the output side of the cross-connect processing circuit A terminal station of the network having a plurality of such second transmission line switching units for switching between an active transmission line that provides the above line and a standby transmission line that is an alternative transmission line to the active transmission line It is a relay device. Further, the cross-connect processing circuit includes a plurality of input side interfaces and a plurality of output side interfaces, and the first transmission path switching unit and the second transmission path switching unit include an input side interface and an output side interface, respectively. have.

The terminal relay device is inserted with an interface unit to a transmission path on the network or an interface unit to a lower network connected to the network, and transmits on the interface to the network or the lower network. A plurality of such slot portions received in the terminal and the receiving terminal;
A first selection unit that selectively connects a receiving terminal on the interface unit inserted into any one of the slot units to an input side interface of the first transmission line switching unit;
A second selector for connecting the output side interface of the first transmission line switching unit to the input side interface of the cross-connect processing circuit;
A third selector for selectively connecting the output side interface of the cross-connect processing circuit to any one of the input side interfaces of the second transmission path switching unit;
A fourth selection unit for connecting the output side interface of the second transmission path switching unit to a transmission terminal on the interface unit inserted into any of the slot units;
Is provided.

  Preferably, the second selection unit associates the reception terminal connected via the first selection unit and the first transmission line switching unit with a slot position into which an interface including the reception terminal is inserted. It may be connected to the input side interface of the cross-connect processing circuit.

  That is, by the combination of the first selection unit and the second selection unit, the reception terminal is connected to the input side interface of the cross-connect processing circuit corresponding to the slot position including the reception terminal. Here, “corresponding to the slot position” means that the logical positional relationship between the slot positions corresponds to, for example, the logical positional relationship between the interfaces on the input side of the cross-connect processing circuit.

Preferably, the third selection unit is connected to the transmission line switching unit and the fourth connection unit via the second transmission line switching unit and the fourth connection unit, and the slot position into which the interface including the transmission terminal is inserted. It may be connected to the output side interface of the cross-connect processing circuit associated with

  That is, the combination of the third selection unit and the fourth selection unit connects the transmission terminal to the output side interface of the cross-connect processing circuit corresponding to the slot position including the transmission terminal.

Preferably, further comprising a quality determination unit for determining the transmission quality of the network,
The first transmission line switching unit or the second transmission line switching unit may switch the working transmission line and the standby transmission line according to the transmission quality.

The present invention also provides a first ring transmission line having an active transmission line in the first direction and a standby transmission line in the first direction, an active transmission line in the second direction, and a second transmission line. Is a terminal relay device connected to a network including a second ring transmission line having a standby transmission line in the direction of
Such a cross-connect processing circuit for performing cross-connect processing of communication channels on the network, and
For the cross-connect processing circuit, an active transmission line from the first direction on the receiving side from the network and a standby transmission line from the second direction serving as an alternative transmission line for the active transmission line A plurality of such first transmission line switching units to be switched;
For the cross-connect processing circuit, on the transmission side to the network, an active transmission line in the first direction and a standby transmission line in the second direction that is an alternative transmission line for the active transmission line, It is desirable to provide such a plurality of second transmission line switching units.

The first transmission line switching unit includes channel information detection means for identifying a communication channel in communication in the working transmission line,
Channel identification means for identifying a communication channel included in such a standby transmission line corresponding to the communication channel used in the active transmission line based on the channel information;
It is preferable to have a switch unit that switches the communication channel of the working transmission line to the communication channel of the standby transmission line that is identified based on the channel identification means.

  According to this terminal relay device, when switching to the standby system, the standby system channel is identified by the channel identification information for identifying the communication channel used in the active system. That is, the standby channel corresponding to the working system is selected and switched by the channel identification information.

Preferably, with respect to the cross-connect processing circuit, a standby transmission line from the first direction serving as an alternative transmission line of the active transmission line and the active transmission line from the second direction on the receiving side from the network A plurality of such third transmission line switching units,
For the cross-connect processing circuit, on the transmission side to the network, a working transmission line in the second direction and a standby transmission line in the first direction serving as an alternative transmission line for the working transmission line, A plurality of such fourth transmission line switching units,
The third transmission line switching unit includes channel information detection means for identifying a communication channel in communication in the working transmission line;
Channel identification means for identifying a communication channel included in such a standby transmission line corresponding to the communication channel used in the active transmission line based on the channel information;
And a switch unit for switching the communication channel of the working transmission line to the communication channel of the standby transmission line identified based on the channel identification means.

  The third transmission path switching unit switches the reception signal from a direction (second direction) different from the reception signal to the first transmission path switching unit. That is, the third transmission path switching unit identifies the communication channel of the received signal from the second direction based on the channel information, and switches between the active system and the standby system.

  Preferably, in the first ring transmission line, the active transmission line and the standby transmission line have different transmission media, and in the second ring transmission line, the active transmission line and the standby transmission line are respectively It may have a different transmission medium.

The present invention also provides such a cross-connect processing circuit for executing cross-connect processing including line setting on a network,
A terminal relay device comprising a control circuit for controlling the cross-connect processing circuit;
The control circuit is
A control transmission line including a plurality of lines corresponding to the transmission line of the network;
A switching unit for switching the line in the control transmission line;
A setting unit that sets a correspondence relationship between the line after switching by the switching unit and the line before switching in the cross-connect processing circuit may be provided.

  Thus, the terminal relay device includes a control transmission line including a plurality of lines corresponding to the transmission line of the network. As a result, it is possible to generate the correspondence relationship of the cross-connect process for the line on the transmission path independently of the transmission path of the network. Therefore, it is possible to obtain control information for setting the cross-connect processing circuit of the transmission line without being affected by the transmission line itself of the network.

  Preferably, an identification information generating unit that generates identification information for identifying the line and inputs the identification information to a corresponding line of the control transmission path may be further provided. By inputting this identification information to the corresponding line of the control transmission path, the correspondence before and after the cross-connect process can be recognized.

Preferably, the control transmission line corresponds to a first control transmission line including a plurality of lines corresponding to an active transmission line included in the network and a standby transmission line included in the network, and the first control transmission line includes The second control transmission line serving as an alternative transmission line of the transmission line,
The switching unit may switch a line between the first control transmission line and the second control transmission line.

Preferably, the control transmission line further includes a third transmission line including a joining side line to the network and a fourth transmission line including a leaving side line from the network,
The switching unit includes an input-side switching unit that switches a line between the first control transmission line, the second control transmission line, or the third transmission line on the input side to the switching unit, and the switching unit. The output side switching unit may include an output side switching unit that switches the line between the first control transmission line, the second control transmission line, and the fourth transmission line.

  Further, the present invention may be a relay method for executing the relay.

  According to the present invention, it is possible to flexibly execute system reconfiguration of a network including a terminal relay device or switching between a working line and a protection line, and provide sufficient services and functions to customers.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
<< First Embodiment >>
Hereinafter, a terminal relay device for a network according to a first embodiment of the present invention will be described with reference to FIGS. Here, an example in which the present invention is applied to an ADX (add, drop cross-connect processing) apparatus on a SONET / SDH optical network (OC-N level) compliant with NNI (Network Node Interface) will be described. Hereinafter, such an ADX apparatus is referred to as a terminal relay apparatus.

The terminal relay device 1 according to the present embodiment includes a pair of interface cards (for working line / protection line / add / drop or east line / west line / add / Connect for drop) without restricting the slot position. In other words, this terminal relay device 1 connects a working line / protection line, east side line / west side line, or add line / drop line to an arbitrary slot position to enable construction of a network.

However, if all the combinations are constructed, the circuit scale becomes enormous and the realization becomes difficult. Therefore, as a hardware configuration, a block (hereinafter referred to as a system block) in which a processing unit for switching between a working line / protection line or an east side line / west side line is bundled in units of OC-48 (STS-1 × 48 ch). It is constituted by). A Line APS processing unit or a BLSR processing unit that executes transmission line switching / switching back processing in the system block is provided.

  Further, the terminal relay device 1 can freely connect the receiving terminal of the interface inserted in the slot and the input side terminal of each system block, or the output side terminal of the system block to the transmitting terminal of the interface inserted in the slot. An application selector that implements is provided. This application selector reduces the circuit scale and realizes a pair configuration of all arbitrary slots.

  Further, an application selector for returning from the system block output to the slot position is provided on the input side of the cross-connect processing circuit. In addition, an application selector from the slot position to the input side of the system block is also provided on the output side of the cross-connect unit.

  With such an application selector, the cross-connect position can be set on the basis of the slot on the front face of the actual terminal relay device 1. Therefore, the user can set the cross connect without being aware of the system block inside the hardware. In the following embodiments, a communication path (for example, OC-1) to be cross-connected is referred to as a line or a channel.

  FIG. 7 shows the configuration of the terminal relay device 1 according to this embodiment. As shown in FIG. 7, the terminal relay device 1 includes a cross-connect processing circuit 2 and various switch circuits provided before and after the cross-connect processing circuit 2 (left and right in FIG. 7).

  Here, it is assumed that the input side circuit (reception side circuit) of the terminal relay device 1 is configured on the left side of the cross-connect processing circuit 2 toward the paper surface of FIG. 7 (indicated by an IN arrow). Further, it is assumed that an output side circuit (transmission side circuit) of the terminal relay device 1 is configured on the right side of the cross-connect processing circuit 1 (indicated by an OUT arrow).

The input side circuit includes slots 3-1 to 3-n for inserting various interface cards,
Input system blocks 4-1 to 4-m for executing Line APS processing, input system blocks 5-1 to 5-m for executing BLSR processing, and slots 3-1 to 3-n as system block 4 Application selector 6-1 connected to the input side of -1 to 4-m, application selector 6-2 connecting slots 3-1 to 3-n to the input side terminals of system blocks 5-1 to 5-m, The application selector 7-1 for connecting the output side terminals of the system blocks 4-1 to 4-m to the input side terminal of the cross-connect processing circuit 2 via the 2: 1 selector 10, and the system blocks 5-1 to 5- an application selector 7-2 for connecting the output terminal of m to the input terminal of the cross-connect processing circuit 2 via the 2: 1 selector 10; have.

  The output side circuit includes slots 3-1 to 3-n for inserting various interface cards, output side system blocks 14-1 to 14-m for executing Line APS processing, and output side system blocks for executing BLSR processing. 15-1 to 15-m, an application selector 17-1 for connecting the output side terminals of the cross-connect processing circuit 2 to the input side terminals of the system blocks 14-1 to 14-m, and the output side of the cross-connect processing circuit 2 The application selector 17-2 for connecting the terminals to the input side terminals of the system blocks 15-1 to 15-m, and the output side terminals of the system blocks 14-1 to 14-m via the 2: 1 selector 20 through the slot 3- From application selector 16-1 connected to 1 to 3-n and system block 15-1 The output terminal of the 5-m 2: 1 and an application selector 16-2 via the selector 20 to connect the slots 3-1 to 3-n.

  Here, the slots 3-1 to 3-n of the output side circuit and the slots 3-1 to 3-n of the input side circuit are the same slot. However, the interface cards connected to the slots 3-1 to 3-n each have an input terminal and an output terminal, and are connected to different fibers. Therefore, in FIG. 7, slots 3-1 to 3-n are arranged on both sides of the terminal relay device 1 for convenience. The slots 3-1 to 3-n arranged on the left side of the terminal relay device 1 correspond to the reception interface and are connected to the input side fiber or the input low speed side transmission path (indicated by IN arrows). The slots 3-1 to 3-n arranged on the right side of the terminal relay device 1 correspond to the transmission interface and are connected to the output side fiber or the output low-order group transmission line (indicated by the OUT arrow). .

  In the present embodiment, slots 3-1 to 3-n have OC-N (for example, OC-48) level transmission lines on the high-order group side or low-order inserted (added) into this OC-N level. An interface card connected to the transmission line on the group side is connected.

  For example, when the high-order group side transmission line constitutes a terminal (1 + 1) or a Line ADM network, an active or standby OC-N level interface card is placed in any of slots 3-1 to 3-n. Inserted.

  When the high-speed transmission line constitutes a UPSR or BLSR, an east-side or west-side OC-N level interface card is connected to one of the slots 3-1 to 3-n.

  Furthermore, the application selectors 6-1 and 6-2 connect the receiving side slots 3-1 to 3-n to any of the input terminals of the system blocks 4-1 to 4-m and 5-1 to 5-m. To do.

  In this case, for the high-order group side transmission path, the input side terminals of the system blocks 4-1 to 4-m are connected to the active system (indicated as “Work” in FIG. 7) and the standby system (indicated as “Protect” in FIG. 7). Transmission lines (or East / West transmission lines in UPSR) are connected.

  Then, the system blocks 4-1 to 4-m select the Line-APS process, that is, the signal of the line with the better quality between the active system and the standby system. That is, the system blocks 4-1 to 4-m switch between the active system and the standby system in units of OC-N according to the transmission quality. A circuit that executes such a selection process is a line switch.

  On the other hand, the low-order group side transmission line is connected to an input side terminal corresponding to either the working system or the standby system of the system blocks 4-1 to 4-m. Connection from the low-order group side transmission path to the terminal relay device 1 realizes insertion processing. In the present embodiment, the low-order group side transmission path is not redundant and is only the active system.

  In addition, transmission lines on the east side (indicated by East in FIG. 7) and the west side (indicated by West in FIG. 7) constituting the BLSR are connected to the input side terminals of the system blocks 5-1 to 5-m. Is done.

  Further, the system blocks 5-1 to 5-m execute reception side processing in BLSR between the east side and the west side. Details of the BLSR process will be described in detail with reference to FIG.

  The application selectors 7-1 and 7-2 connect the output side terminals of the system blocks 4-1 to 4-m and 5-1 to 5-m to the cross-connect processing circuit 2 via the 2: 1 selector. At this time, the application selector 7-1 connects the output side terminals of the system blocks 4-1 to 4-m to the terminals of the cross-connect processing circuit 2 corresponding to the slot positions of the slots 3-1 to 3-n. Thereby, for example, the working channel connected to the slots 3-1 to 3-n does not depend on the connection to the system blocks 4-1 to 4-m, and is at a position corresponding to the original slot position. Connected to the terminal of the cross-connect processing circuit 2.

  Therefore, the setting of the cross-connect processing circuit 2 for the active channel is not dependent on the connection from the system blocks 4-1 to 4-m, and is performed based on the positions of the slots 3-1 to 3-n. Just do it. In the present embodiment, such setting is referred to as setting of the cross-connect processing circuit 2 based on the slot.

  The 2: 1 selector 10 is a circuit that selects one of the output-side terminals of the application selectors 7-1 and 7-2 and connects it to the input-side terminal of the cross-connect processing circuit 2.

  Here, the setting based on the slot reference is illustrated. Assume that slot numbers 1 to n are assigned to slots 3-1 to 3-n. Assume that the working channel is connected to these slots. A case is assumed in which terminal numbers 1 to n are assigned to the terminals on the input side of the cross-connect processing circuit 2.

  In this terminal relay device, from the slot 3-1 with slot numbers 1 to n connected to the active channel without depending on the processing by the system blocks 4-1 to 4 -m and 5-1 and 5 -m. 3-n is connected to the input-side terminals 1 to n of the cross-connect processing circuit 2, respectively.

This is because slots 3-1 to 3-n are connected to input terminals of system blocks 4-1 to 4-m or 5-1 to 5-m by application selectors 6-1 and 6-2. Thereafter, the application selectors 7-1 and 7-2 (and the 2: 1 selector 10) make the terminal numbers corresponding to the original slot numbers corresponding to the output terminals of the system blocks 4-1 to 4-m or 5-1 to 5-m. This is because it is connected to the input side terminal of the cross-connect processing circuit 2.

  That is, according to the terminal relay device 1, the connection relationship between the application selectors 6-1 and 6-2 set for inputting to the system blocks 4-1 to 4-m or 5-1 to 5-m is established. Returned to the original by the application selectors 7-1, 7-2 and the 2: 1 selector 10.

  The cross-connect processing circuit 2 connects the input side terminal to the output side terminal, and converts the time slot on the input side transmission path to the time slot on the output side transmission path. Channels are converted in spatial transmission paths and time slots by the processing of the cross-connect processing circuit 2. This process is called TSI (Time Space Interchange). Due to this TSI, the output side terminal of the cross-connect processing circuit 2 is terminated from the active channel / standby channel, east side channel / west side channel, or low speed side transmission line connected to any of the input side terminals. The channel inserted by the station relay device is connected.

  The application selectors 17-1 and 17-2 connect the output side terminal of the cross-connect processing circuit 2 to any one of the input terminals of the system blocks 14-1 to 14-m and 15-1 to 15-m.

  Among these, the input side terminals of the system blocks 14-1 to 14-m are connected to the transmission path of the active system (indicated as “Work” in FIG. 7), the standby system (indicated as “Protect” in FIG. 7), or the low speed side transmission. The channel from the road is connected.

  In this case, between the output side terminal of the system block 4-1 etc. and the input side terminal of the system block 14-1 etc. (in FIG. 7, the system blocks 4-1 to 4-m and the system block 14-1 Basically, there is only an active signal in the circuit between 2 and 14-m. This is because the APS process is performed on the high-order group data by the line switch 22 and the like, and the low-order group data is passed through.

  However, the terminal relay device 1 of the present embodiment also considers application to other applications, so that both the active and standby transmission lines are connected to the output side terminals such as the system block 4-1. Have. For example, in FIG. 7, the input / output terminals of the application selectors 7-1 and 17-1 and the input-side terminals of the system blocks 14-1 to 14-m include the active system signal (Work) and the standby system. A signal (Protect) is shown.

  The system blocks 14-1 to 14-m branch the output signal to both the active system and the standby system and transmit it. A circuit that executes such branch processing is a bridge.

  In addition, transmission lines on the east side (indicated by East in FIG. 7) and the west side (indicated by West in FIG. 7) constituting the ring are connected to the input side terminals of the system blocks 15-1 to 15-m. Is done.

  Further, the system blocks 15-1 to 15-m execute the transmission side processing in BLSR between the east side and the west side.

  For example, the system blocks 15-1 to 15-m execute loopback processing in units of OC-N between the east side and the west side when a failure occurs in the transmission destination on the east side. Thereby, the return of the transmission path from the east side to the west side is realized. The BLSR process will be described in detail with reference to FIG.

  The application selectors 16-1, 16-2 and 2: 1 selector 20 connect the output side terminals of the system blocks 14-1 to 14-m and 15-1 to 15-m to the corresponding slot numbers. Here, the corresponding slot means a slot corresponding to the output side terminal of the cross-connect processing circuit 2 connected to each input side terminal of the system blocks 14-1 to 14-m and 15-1 to 15-m. .

  Assume that slot numbers 1 to n are assigned to slots 13-1 to 13-n connected to the working channel on the output side (the side indicated by the OUT arrow in FIG. 7). Further, it is assumed that terminal numbers 1 to n are assigned to the terminals on the output side of the cross-connect processing circuit 2.

  In the terminal relay device 1, the active channel does not depend on the processing by the system blocks 14-1 to 14-m and 15-1 to 15-m, and the output side terminals 1 to n of the cross-connect processing circuit 2 are used. Are connected to slots 13-1 to 13-n of corresponding slot numbers 1 to n, respectively. This function is the same as that of the application selectors 6-1, 6-2, 7-1, 7-2 and the 2: 1 selector 10.

  FIG. 8 shows an example in which an application having a terminal (1 + 1) configuration is actually constructed using the OC-N interface card by the terminal relay devices 1 and 1. In this configuration, the working card and the standby card that interface with the higher-order group side are assigned to the slot 3-2 (Slot # 2) and the slot 3-3 (Slot # 3), and the slot 3-5 (Slot # 5). Is equipped with a card that interfaces with the low-order group side.

  In this configuration, on the high-order group side, the two optical fibers F1 and F2 constitute an active transmission transmission path and a reception transmission path. The other two optical fibers F3 and F4 constitute a standby transmission transmission line and reception transmission line.

  The interface card mounted in the slot 3-5 converts the electrical signal input from the cable C2 into an optical signal. Then, the signal from the low-order group side is branched into a working channel (Work) and a protection channel (Protect) by the line bridge 21 in units of OC-N (for example, OC-48). The working channel is output to the fiber F1 through the output terminal of the slot 3-2 (Slot # 2). Further, the standby channel is output to the fiber F3 through the output terminal of the slot 3-3 (Slot # 3).

On the other hand, for the higher-order group input channels, the working channel is input from the fiber F2 through the input terminal of the slot 3-2 (Slot # 2). The standby channel is input from the fiber F4 through the input terminal of the slot 3-3 (Slot # 3).

  The higher-order group channels input to the slots 3-2 and 3-3 are selected by the line switch 22 in units of OC-N (for example, OC-48). Then, the selected channel is output to the low-order group side through the interface card mounted in the slot 3-5. That is, the interface card mounted in the slot 3-5 converts the optical signal into an electrical signal and outputs it from the cable C1.

  FIG. 9 shows an example of cross-connect processing of the terminal relay device 1 in the application of FIG. FIG. 9 shows an example in which a drop from a higher-order group to a lower-order group or an insertion (add) from a lower-order group to a higher-order group is realized by the card configuration of FIG. The components of the terminal relay device 1 are as described in FIG.

First, in the drop direction, the transmission paths of the active card and the standby card on the higher-order group side are connected to the system block 4-1 via the application selector 6-1. The system block 4-1 monitors the transmission line quality of the transmission data from the higher-order group side. Then, automatic switching between the active system and the standby system, that is, APS (Automatic Protection Switch) is performed using the monitoring result as a trigger. This switching is executed by the line switch 22.

  Next, the data subjected to the APS process is returned from the position of the system block 4-1 to the position of the slot 3-2 (Slot # 2) via the application selector 7-1 and connected to the cross-connect processing circuit 2. Here, returning to the position of the slot 3-2 (Slot # 2) means that the data subjected to the APS process is a terminal number (for example, terminal number 2) corresponding to the slot number (for example, slot number 2) of the slot 3-2. ) Is connected to the terminal of the cross-connect processing circuit 2.

  Further, in the example of FIG. 9, the above-described APS-processed data is line-set at the position of the slot 3-5 (Slot # 5) where the low-order group card is inserted by the cross-connect processing circuit 2. (The line setting itself of the cross-connect processing circuit 2 is based on user designation, for example).

  The cross-connected data is connected to the system block 14-3 via the application selector 17-1, and the APS process is not performed, and the data is left through. This data is connected to the card in slot 3-5 (Slot # 5) via the application selector 16-1, and is output to the low-order group side.

  Next, in the insertion (add) direction, transmission data from the card in the slot 3-5 (Slot # 5) on the low-order group side is connected to the system block 4-3 via the application selector 6-1. The system block 4-3 does not perform the APS process for the low-order group data. Therefore, the data is passed through as it is, and is returned from the position of the system block 4-3 to the position of the slot 3-5 (Slot # 5) via the application selector 7-1 and is input to the input side terminal of the cross-connect processing circuit 2. Connected.

  Further, the cross connection processing circuit 2 sets a line in the slot 3-2 (Slot # 2) in which the active card on the higher-order group side is inserted. The cross-connected data is connected to the active system side of the system block 14-1 via the application selector 17-1. Then, after branching to the standby side by the line bridge 21 in the system block 14-1, the slot 3-2 (Slot # 2) and the slot 3-3 (Slot # 3) are passed through the application selector 16-1. Is output to the higher-order group side.

  As described above, the signal in the slot 3-2 connected to the active channel in the input side circuit is connected to the input side terminal in the corresponding positional relationship of the cross-connect processing circuit 2. On the other hand, the signal of the slot 3-3 connected to the backup channel is used as a backup system of the signal of the slot 3-2 in the line switch 22.

  Also in the output side circuit, the signal of the slot 3-2 connected to the active channel is connected to the output side terminal in the corresponding positional relationship of the cross connect processing circuit 2. On the other hand, the signal in the slot 3-3 connected to the standby channel is branched from the signal in the slot 3-2 by the line bridge 21.

FIG. 10 shows a configuration of a line switch and a line bridge for 1 + 1 Line APS processing in the system block. In this embodiment, the processing capacity in one system block is OC-N (for example, OC-48) 2 fiber configuration (1 fiber = STS-1 × 48 ch).
). The system block 4-1 and the like perform switching control between the active system and the standby system at the time of a transmission line failure with this OC-N as a unit.

In the terminal (1 + 1) system shown in FIG. 10, the transmission lines are assigned in the first system (channels 1 to 24), the second system (channels 25 to 48), and the third system (backup channels (channels 1 to 24)). The fourth is a standby system (channels 25 to 48).

  In FIG. 10, the working channels 1 to 24 and 25 to 48 of the receiving side block 4-1 correspond to one optical fiber. The standby channels 1 to 24 and 25 to 48 correspond to one optical fiber.

  Furthermore, in actual communication in the 1 + 1 system, one fiber is used for each of the working system 14-1 and the standby system of the transmission side block. As a result, in the 1 + 1 system communication, four fibers are used between nodes.

  In the case of the UPSR configuration, for example, one system of the east side channels (active systems 1 to 48) is connected in the clockwise direction and one system in the counterclockwise direction. Further, one system is connected to the west side channels (standby systems 1 to 48) in the clockwise direction and one system in the counterclockwise direction. With this configuration, in the entire UPSR, one optical fiber is laid in the clockwise direction and one optical fiber in the counterclockwise direction.

  The alarm indicator signal (hereinafter referred to as AIS) generators 23 and 24 notify the device using the backup system of an alarm to that effect when the working channel is disconnected. As a result, when the standby system is not used, the apparatus using the standby system is notified that the standby system is no longer in an unused state and cannot be used. That is, in the 1 + 1 configuration network, as long as no alarm is output from the AIS generators 23 and 24, the standby channel can be used.

  As shown in FIG. 10, in the system block 4-1 on the receiving side, the standby channels (Protect) 1 to 24 and the active channels 1 to 24 are connected to the line switch 22A. As described above, in the 1 + 1 Line APS process, the same signal is transmitted to both the active channel and the standby channel. Then, the channel quality is compared, and a channel with good channel quality is selected and output by the line switch 22A in units of OC-N. The line switch 22B executes the same processing for the channels 25 to 48.

  Further, in the transmission-side system block 14-1, the working channels 1 to 24 are branched to the standby channels 1 to 24 by the line bridge 25. In addition, the working channels 25 to 48 are branched to the standby channels 25 to 48 by the line bridge 26. In this way, the transmission-side system block 14-1 and the like generate redundant signals in the active channel and the standby channel.

  With the above configuration, when the user sets the cross-connect processing circuit 2, the connection between the system blocks 4-1 to 4 -m and 14-1 to 14 -m that execute the Line APS process and the presence or absence of the process are determined. Regardless, signals to the input terminals (for example, terminal numbers 1 to n) of the cross-connect processing circuit 2 are sent from slots 3-1 to 3-n on the input side of the active system (left side in FIGS. 7 and 9). (For example, slot numbers 1 to n).

Further, signals to the output terminals (for example, terminal numbers 1 to n) of the cross-connect processing circuit 2 are sent from slots 3-1 to 3-n (on the right side in FIGS. 7 and 9) of the active system. For example, it corresponds to slot numbers 1 to n). Therefore, the user can set the cross-connect processing circuit 2 based on the slot number for identifying the slot.

  In the above embodiment, an example in which the terminal relay device 1 is applied to a network having a terminal (1 + 1) configuration is shown. However, even in a linear configuration in which three or more terminal relay devices 1 are combined, the procedure is the same as described above as long as the signal is branched into both the active system and the standby system and the selection process is executed on the receiving side.

That is, the terminal relay device 1 can be similarly applied to a linear configuration in which three or more terminal relay devices 1 are linearly arranged and a UPSR configuration in which signals are output to both the east / west ring. it can.
<Example of BLSR application>
Even in the BLSR application, it is possible to realize the connection between the slot and the system block as described above and the setting of the cross-connect processing circuit 2 that is not conscious of the system block.

FIG. 11 shows a configuration at the time of BLSR processing in the system blocks 5A-1 and 15A-1 of the four-fiber BLSR. In FIG. 11, the working systems 1 to 24 channels, the working systems 25 to 48 channels, the standby systems 1 to 24 channels, and the standby systems 25 to 48 channels respectively correspond to different optical fibers.
The system blocks 5A-1 and 15A-1 and the like perform switching control between the active system and the standby system when a transmission path failure occurs.

  As shown in FIG. 11, the four BLSR transmission line assignments are the first in the East working system (East-Work), the second in the East standby system (East-Protect), and the third in the West working system (West-Work). Work), and the fourth is a West-Protect system.

As shown in FIG. 11, the receiving system block 5A-1 has a span switch 27 between the east active system and the east standby system, and between the east active system and the west standby system. A ring switch 28 is provided.

  The span switch 27 switches a channel to be taken out between the east active system and the east standby system in units of OC-N.

  The ring switch 28 switches the channel to be taken out between the east active system and the west standby system in units of OC-N. The ring switch 28 executes a process of capturing (dropping) data that should be transmitted on the east side from the west side.

The transmission system 15A-1 has a span bridge 29 between the east active system and the east standby system, and a ring bridge 30 between the east active system and the west standby system. Have.

  When a failure occurs in the east working channel, the span bridge 29 branches the east working signal to the east standby system in units of OC-N.

  When a failure occurs in both the east active system and the standby system, the ring bridge 30 switches the signal of the east active system to the west standby system in units of OC-N. By this ring bridge 30, data that should originally be transmitted in the east direction is sent back to the transmission path in the west direction.

<Application to devices where Line APS and UPSR coexist>
As shown in FIG. 7, the terminal (1 + 1) is switched by switching between the 2: 1 selector 10 in front of the cross-connect processing circuit 2 and the 2: 1 selector 20 in front of outputting from the output side slots 3-1 to 3-n. ) Configuration and BLSR configuration can coexist.

  That is, by the combination of the 2: 1 selectors 10 and 20, the transmission path of the Linear ADM configuration (or terminal configuration) and the transmission path of the BLSR configuration can be switched in units of OC-N (for example, OC-48). Therefore, according to the terminal relay device 1 of this embodiment, it is possible to construct a plurality of applications in one device.

<Generalization to OC-N>
As described above, for example, by configuring one system block based on OC-482 fiber, two system blocks are used for OC-48 four-fiber BLSR, and four system blocks are used for OC-192 two-fiber. In the case of OC-192 4-fiber BLSR, it can be realized by combining eight Sys blocks.

  In the case of a two-fiber BLSR, the active and standby bands are allocated within one fiber. In this case, the redundant configuration is realized by east and west fibers. Therefore, the span switch 27 and the span bridge 29 for making the working system and the standby system of the east redundant are unnecessary (the same applies to the west).

<Other variations>
In the above embodiment, an example in which the present invention is implemented in SONET / SDH has been shown. However, the implementation of the present invention is not limited to SONET / SDH. That is, the present invention can be implemented in general relay apparatuses having a switching function between the active system and the standby system and a cross-connect processing function.
<< Second Embodiment >>
Hereinafter, a terminal relay device for a network according to a second embodiment of the present invention will be described with reference to FIGS. In the first embodiment, the configuration of the terminal relay device 1 in the network that executes the 1 + 1 Line APS process and the BLSR process has been described.

  In the present embodiment, a procedure for upgrading a network in a service state (hereinafter referred to as in-service upgrade) using the terminal relay device 1 will be described. The configuration and function of the terminal relay device 1 are the same as those in the first embodiment. Therefore, the same components are denoted by the same reference numerals and the description thereof is omitted.

There are two types of in-service upgrades. The first type increases physical transmission capacity in currently built applications (eg, OC-12
Is changed to OC-48). The second type is a case where the system application is changed without changing the transmission capacity (for example, UPSR is changed to BLSR).
<Upgrade example from UPSR to BLSR>
FIG. 12 to FIG. 14 show a procedure for upgrading an application from UPSR to BLSR by the relay device 1.

  In FIG. 12, an interface card for interfacing with the higher-order group side is inserted into slots 3-2 and 3-3. In addition, an interface card for interfacing with the low-order group side is inserted in the slot 3-5.

The system blocks 4-1 and 4-3 are provided with line switches similar to those in the first embodiment, and the selection of the active / standby system or the insertion from the low-order group is realized. Further, the system blocks 14-1, 14-3, etc. are provided with the same line bridge as in the first embodiment, and output of signals to both the active system and the standby system or drop to the low-order group is realized. . With such a configuration, the terminal relay device 1 constitutes a node of the UPSR ring. For example, the interface card in the slot 3-2 may be connected to the east side, and the slot 3-3 may be connected to the west side.

  12 to 14, the system blocks 5-1, 5-3, etc. have the same configuration as the receiving-side system block 5-1 shown in FIG. 11. The system blocks 15-1, 15-3, etc. have the same configuration as the system block 15-1 on the transmission side shown in FIG. As in the case of FIG. 11, the system blocks 5-1, 15-1 and the like provide BLSR applications by span switches, ring switches, span bridges, and ring bridges (however, in the case of 2F-BLSR, span switches and Span bridge is not used).

  Hereinafter, the UPSR is upgraded to BLSR without stopping the service in accordance with the procedure shown in FIGS. 13 and 14.

  First, in FIG. 13, transmission data from slots 3-2, 3-3 and 3-5 are branched, and system blocks 5-1 and 5-3 on the BLSR side are passed through application selectors 6-2 and 7-2. Connect to.

  Similarly, the transmission data after the cross connection is connected to the system blocks 15-1 and 15-3 via the application selectors 17-2 and 16-2.

  Then, the data on the BLSR side is passed to the 2: 1 selector 10 in front of the cross-connect processing circuit 2 (on the left side in FIG. 12 to 14). Further, a BLSR system is constructed by passing the data on the BLSR side to the front of the 2: 1 selector 20 before the output to the interface card such as the slot 3-2.

  Next, in FIG. 14, the settings of the 2: 1 selector 10 in front of the cross-connect processing circuit 2 and the 2: 1 selector 20 in front of outputting to the interface card are switched to the BLSR side selection. Since both UPSR and BLSR signals are passed through the 2: 1 selectors 10 and 20, the switching process can be easily executed.

This completes the upgrade from UPSR to BLSR without stopping the service.
<Example of upgrade from Linear ADM (1 + 1) configuration to BLSR>
Hereinafter, an in-service upgrade from an OC-N (for example, OC-48) Linear ADM (1 + 1) configuration to an OC-N 4 fiber BLSR will be described as an example. Here, 1 + 1 means that the same number of fibers are used in the active system and the standby system.

  FIG. 15 shows a procedure for upgrading from a linear ADM configuration to a 4-fiber BLSR. The upper part of FIG. 15 shows a network having a Linear ADM (1 + 1) configuration before the upgrade.

  This network is configured by connecting the terminal relay devices 1A, 1B, and 1C constituting the nodes A, B, and C through transmission lines of the active system (Work) and the standby system (Pctt). The terminal relay devices 1A, 1B, and 1C have the same configuration as that described in the first embodiment.

  When upgrading from a linear ADM configuration to a 4-fiber BLSR as shown in FIG. 15, a shaded interface card (indicated by the letters “add” in FIG. 15) is added to node A and node C, and node A and node C are added. And the fiber F10 is connected to each other and each node is set to the BLSR mode, the upgrade is completed. However, when upgrading to the 4-fiber BLSR, it is necessary to switch the application selector connected to the system block.

  This switching is shown in FIGS. 16A and 16B and FIGS. 17A and 17B. 16A and 16B are diagrams showing the setting contents of the application of the node B before the upgrade. FIGS. 17A and 17B are diagrams showing application settings at the time of four-fiber BLSR.

  In these figures, PTCT indicates a protection system (Protect). WORK indicates an active system. Furthermore, in these figures, the locations indicated by the symbols (A-1), (A-2), (A-3), and (A-4) indicate the connection locations.

  As shown in FIGS. 16A and 16B, the terminal relay device 1B according to the present embodiment includes application selectors 6-1 and 7-1 before and after the system blocks 4-1, 4-2, 4-3, and the like. ing. By the application selectors 6-1 and 7-1, on the input side (indicated by the IN arrow), the active signals input to the slots 3-1, 3-2, etc. are directly connected to the cross-connect processing circuit. 2 input side terminals. This operation is the same as that described in the first embodiment. Similarly, the relationship between the output-side terminal of the cross-connect processing circuit 2 and the active signal output from the slots 3-1, 3-2, etc. on the output side (indicated by the OUT arrow) is also the application selector 17. -1 and 16-1.

  In general, the arrangement of signals at the output side terminals of the system blocks 5-1, 5-2, 5-3, etc. when the 4-fiber BLSR is set is the system blocks 4-1, 4-2, 4, when the 1 + 1LineaADM is set. -3 does not match. However, due to the action of the application selectors 6-2 and 7-2, the signal arrangement of the output side terminals of the system blocks 5-1, 5-2 and 5-3 is the signal at the input side (indicated by the IN arrow) slot. Is returned to the array. This operation is the same as that described in the first embodiment.

  Therefore, the signals at the output side terminals of the application selectors 7-1 and 7-2 correspond to the input side slots 3-1, 3-2, etc., regardless of the presence / absence of 1 + 1LineaADM and the presence / absence of BLSR processing.

  This correspondence is similarly maintained between the output-side terminal of the cross-connect processing circuit 2 and the slots 3-1 and 3-2 on the output side (indicated by OUT arrows).

  As described above, the current application is maintained in service even when each setting for a new application is performed by configuring the Linear ADM / UPSR system and the BLSR system in parallel. When the new application is ready, the 2: 1 selectors 10 and 20 are switched to instantly upgrade to the new application. Further, it is possible to minimize the degradation of transmission quality during the upgrade.

  If the application selectors 6-1, 6-2, 7-1, 7-2, 16-1, 16-2, 17-1, 17-2, etc. before and after the cross-connect are not provided, the cross-connect process The circuit 2 is set on the basis of the system block. The system block reference means that it is necessary to identify the arrangement of output signals of the system block.

  Therefore, when upgrading from 1 + 1 LinearADM to 4-fiber BLSR, cross-connect replacement is required. In this case, the main signal is interrupted.

  As a means for avoiding this, the terminal relay device 1A or the like is configured so that the application selectors 6-1, 6-2, 7-1, 7-2, 16-1, 16-2, 17-1, 17-2. As a result, the cross-connect setting on the slot basis becomes possible. Therefore, as shown in FIGS. 16A and 16B and FIGS. 17A and 17B, the setting of the cross-connect processing circuit 2 does not need to be changed when upgrading from Linear ADM to 4 fibers, and disconnection of the main signal can be avoided.

<Modification>
In the above embodiment, an example in which the present invention is implemented in SONET / SDH has been shown. However, the implementation of the present invention is not limited to SONET / SDH. That is, the present invention can be implemented in general relay apparatuses having a switching function between the active system and the standby system and a cross-connect processing function.
<< Third Embodiment >>
Hereinafter, a terminal relay device for a network according to a third embodiment of the present invention will be described with reference to FIGS. In the first embodiment, the configuration of the terminal relay device 1 that can flexibly set 1 + 1 Line APS, UPSR, and BLSR has been described. In the second embodiment, the procedure for upgrading the network without stopping the service by the terminal relay device 1 has been described.

  In the present embodiment, a terminal relay device that can flexibly correspond to a working channel and a standby channel in BLSR will be described.

  In the conventional BLSR network, data sent from the start node is delivered to the end node via the intermediate node. When a relief operation occurs due to a failure, data is delivered to the end point node through a path different from the normal operation path.

  In this case, in general, the time slot at the start node and the time slot of the active system and the standby system at the end node have a fixed relationship. By fixing the relationship between the active and standby time slots, it is possible to guarantee the connection after the path change for any time slot, that is, any active channel. However, in such a network, replacement of the used time slot (cross-connect) in the intermediate through node is not allowed in the normal operation state.

  The terminal relay device according to the present embodiment allows a replacement operation in the event of a failure while allowing the time slot to be changed at the intermediate through node.

  In general, in the data to be transmitted, a path ID designating a node unique number and a channel number is defined at the start node. The path ID is defined in, for example, SONET / SDH, and is information used by higher layer software mainly for identifying between communicating nodes. In this embodiment, this path ID is used for time slot recognition.

  The path ID is transferred using overhead bytes. Even when the time slot is cross-connected in the intermediate node, the path ID is transmitted together with the channel transmission data. Therefore, if this path ID is monitored at the end point node, the path before the change can be recognized and the connection can be confirmed even when the time slot is changed.

  In this embodiment, the path ID is used to determine whether the reception channel rescued by the BLSR rescue method is received by a different channel. That is, it is determined by the path ID on which channel the data received at the end node during normal operation is received after the rescue.

  That is, in this embodiment, when the time slot is changed, it is confirmed by the path ID which time slot the data during normal operation is received. From the viewpoint of preventing erroneous connection, a unique path ID must be defined in the BLSR.

  In the BLSR line relief of this embodiment, the BLSR ring switch procedure is executed as in the prior art. That is, the terminal relay device of the present embodiment performs a loopback when a failure occurs, and switches the transmission path to a backup line in the reverse direction. If the cross connection is set at the intermediate node at the time of setting the working line, the relief may not be possible because the reception time slot is different although the communication between the nodes is possible.

  FIG. 18 shows a BLSR including the terminal relay devices 101, 102, 103, and 104 according to the present embodiment. In FIG. 18, the terminal relay device 101 transmits data to the terminal relay device 103 via channel 1. This channel 1 is changed to channel 3 in the terminal relay device 102. Therefore, the terminal relay device 103 that is a receiving node drops the channel 3 to the lower order side.

  FIG. 19 shows a state where a single failure has occurred. Here, the fault location is indicated by a cross. As shown in FIG. 19, at the time of a single failure, the handling time slots before and after the failure are the same (the channel is 3 before and after the failure point). Therefore, even when a loopback for relief is performed, the time slot before the relief is connected to the same time slot as the connection destination, and the relief can be performed by a conventional method.

  In other words, the terminal relay device 102 in front of the failure part determines that transmission in the forward direction (west direction) is impossible, and transmits the signal after returning in the east direction. The looped-back channel passes through the terminal relay devices 101 and 104 and reaches the terminal relay device 103. The terminal relay device 103 may drop the same channel from the west side as before the failure occurs.

  Note that the standby channel to be used is determined, for example, by a repair procedure defined in SONET / SDH. In this embodiment, in FIG. 19, this standby channel is indicated as “CH3 + WKch”.

  FIG. 20 shows an example of multiple failures. Here too, the fault location is indicated by a cross. As shown in FIG. 20, in the case of multiple failures (fiber failures in multiple paths, node failures), an intermediate node that is isolated due to the failure occurs. In the example of FIG. 20, the node of the terminal relay device 102 is isolated. In the terminal relay device 102, the channel, that is, the time slot is exchanged.

  Thus, when data is cross-connected to another time slot in an isolated node, the setting of the cross-connect cannot be recognized in the fault neighboring node. Therefore, if loopback, which is a conventional normal rescue measure, is executed, the data that is looped back cannot be rescued as in normal operation.

  This is because a cross-connect of through data executed in an isolated node cannot be automatically recognized, and different time slots are connected to each other.

  In order to prevent this erroneous connection, the data receiving node (terminal relay apparatus 103 in FIG. 20) may detect the path ID when receiving the loopback data. The data receiving node of this embodiment compares the path ID received during normal operation with the path ID received during loopback control, and executes relief.

  FIG. 21 shows an outline of the relief process. When the same path ID is received in the same time slot before and after the failure, the terminal relay device 103 does not replace the time slot. On the other hand, if the comparison result between the pre-failure path ID and the post-failure path ID is different, the terminal relay device 103 switches the time slot before the loopback selector 110 is executed as shown in FIG. This enables reception from a time slot having a pre-failure path ID.

  Conventionally, squelch control using a squelch table is performed for preventing erroneous connection of lines. However, when multiple failures occur, squelch control cannot be used to relieve communicable data that has been cross-connected. Even for such a path that is not relieved even if the conventional squelch control is used, it is possible to relieve if a path ID is detected on the receiving side and a cross connection is performed.

  FIG. 22 shows an internal functional block of a circuit that executes the path ID detection process. This circuit is mounted, for example, in the system block 5A-1 on the receiving side shown in FIG.

  As shown in FIG. 22, for example, assuming an OC-48 2F-BLSR, this system block is connected to the working channels 1 to 24, the standby channel 25 or 48, and the multiple failure information channel 120. The In FIG. 22, solid arrows indicate data signals (signals transmitted through the respective channels), and dotted arrows indicate control signals.

  This system block includes a normal path ID detection unit 121, a failure path ID detection unit 122, a path ID comparison unit 123, a time slot comparison unit 124, a time slot replacement unit 125, a BLSR switch 126, and a squelch management unit 127. .

  The normal time path ID detection unit 121 detects the path ID in the data input from the working time slot (ch1-24) at the normal time, and holds the ID. The normal path ID detection unit 121 performs a holding operation so that the held path ID is not changed when a failure occurs (when multiple fault information is input).

  The failure path ID detection unit 122 detects the path ID in the data input from the standby time slot (ch25-48) based on the multiple failure occurrence information, and holds the path ID. However, at times other than when a failure occurs (when multiple failure information is input), the failure-time path ID detection unit 122 holds a path ID undetected code.

  The required path ID is the path ID of the channels 1 to 24 on the active side in the normal operation state. When multiple failures occur, it is necessary to monitor the path IDs of the standby channels 25-48.

  The recognition of the state at the time of normal / failure occurrence can be recognized by using ring switch information used for BLSR relief. This circuit uses this ring switch information as multi-fault information. The ring switch information is, for example, information indicating a switching state of the ring switch 28 that switches the reception-side channel illustrated in FIG. 11 between the active system and the standby system in the first embodiment.

  When the execution of relief is notified by this ring switch information, the path ID information of the working channels 1 to 24 stored in the normal path ID detection unit 121 cannot be changed. On the other hand, the path ID received in the protection channels 25 to 48 is detected by the failure path ID detection unit 122. Then, the path ID of the normal-time path ID detection unit 121 is compared with the path ID received by the standby channels 25 to 48.

  Note that, in the case of relief in BLSR in which the time slot is not replaced by a through node as in the conventional case, the same data is received in the active channel 1 and the standby channel 25. In the case of such a rigid channel configuration, detection of the path ID as in the present embodiment is not necessary.

  The path ID comparison unit 123 compares the ID held by the normal path ID detection unit 121 and the path ID held by the failure path ID detection unit 122 when multiple failures occur. Here, the path ID that matches the path ID held at each time slot position of the normal time path ID detection unit 121 is detected from the path ID detected at the time of failure.

  The path ID comparison unit 123 inputs the comparison result to the time slot control unit 124. The time slot control unit 124 controls the time slot replacement unit 125 according to the comparison result.

  The time slot switching unit 125 is enabled when the multiple failure information 120 is input, and switches the standby channels 25 to 48 in accordance with an instruction from the time slot control unit 124. This exchanged channel is input to the BLSR switch 126. Here, the BLSR switch 126 is, for example, the ring switch 28 in FIG.

  FIG. 23 shows circuit configurations of the path ID comparison unit 123 and the time slot control unit 124. The path ID comparison unit 123 compares, for example, a path ID for identifying a time slot of channel 1 detected by the normal path ID detection unit 121 with a path ID held in the failure path ID detection unit 122 (see FIG. Middle E-NOR circuit 130). In the case of FIG. 23, the output of the E-NOR circuit 130 with the matching path ID becomes true.

  If no matching path ID is found as a result of the comparison, it is recognized that no detection has been made. Based on the true output of the E-NOR circuit 130, the time slot control unit 124 associates the time slot stored in the normal path ID detection unit 121 with the time slot detected by the failure path ID detection unit 122. Do.

  That is, the channel at the time of failure is selected through the AND circuit 131 based on the output of the E-NOR circuit 130 with the matching path ID. If no matching path ID exists, an AIS output flag is set through the AND circuit 132.

  The time slot replacement unit 125 in FIG. 22 replaces the time slots according to the above selection. When the AIS output flag is set, the time slot replacement unit 125 outputs an AIS signal.

As described above, according to the terminal relay device 101 and the like of the present embodiment, it is possible to relieve when a multiple failure occurs while allowing the replacement of time slots in the through node. Therefore, the setting of the time slot at the through node becomes flexible, and the reliability of the system by BLSR is maintained.
<< 4th Embodiment >>
Hereinafter, a terminal relay device for a network according to a second embodiment of the present invention will be described with reference to FIGS. In the first embodiment, the configuration of the terminal relay device 1 in the network that executes the 1 + 1 Line APS process and the BLSR process has been described. In that case, the application selector 6-1 and the like of the first embodiment, the system block 4-1 and the 2: 1 selector 10 and the like switched the main signal of the direct transmission path.

Thus, as a conventional terminal relay device, Line before and after the cross-connect processing circuit
A configuration in which a circuit for executing an application such as APS or BLSR is provided and a main signal is directly operated is common.

  In the present embodiment, a control circuit for processing control signal identification information (hereinafter referred to as a passcode) is provided independently of the main signal. This control circuit executes processing such as Line APS and BLSR along with the cross-connect processing on the passcode. Then, a correspondence relationship between the pass code input to the control circuit and the pass code output from the control circuit is obtained.

The correspondence relationship of the pass codes indicates to which output channel the input channel to the terminal relay device should be connected. This control circuit sets the main signal of the cross-connect processing circuit according to this correspondence.
<Conventional example>
FIG. 24 shows an example of a circuit for cross-connect processing and active / standby switching processing in a conventional terminal relay device. This circuit has a main signal system circuit and a control system circuit.

  As shown in FIG. 24, the main signal system circuit includes a switch unit 40, a cross-connect processing circuit 42, a service selector 45, a path switch 46, and a bridge unit 41. The control system circuit includes cross-connect control code setting units 43 and 44, an alarm detection unit 47, and a path switch / service selector processing unit 48.

  The switch unit 40 performs a Line APS process. In other words, the switch unit 40 selects and switches the line quality (in units of OC-N) with the better line quality between the active system and the standby system of the received signal. Further, the switch unit 40 provides the same function as that of the receiving-side system block 5-1 shown in FIG. 11 during the BLSR processing.

  The service selector 45 and the bridge unit 41 execute BLSR processing in the ring network. For example, when a failure occurs in the transmission channel (E-WK) of the east side active system, the bridge 41 sends a signal to the transmission side channel (E-WK) of the east side active system to the west side standby system (W-). (PT) transmission channel. This process is the same as the process of the system block 15-1 shown in FIG. 11 of the first embodiment.

  Here, the service selector 45 includes a through signal (higher order group constituting the BLSR, that is, a signal on the east side or the west side) and an insertion (add) signal among the signals on the input side, that is, relay from the second BLSR to the terminal station. Switches the signal input to the device. The second BLSR refers to another BLSR connected to the BLSR focused on in a network including a plurality of BLSRs.

  The input signals (indicated by IN arrows) in FIG. 24 include the east active system (E-WK), the east standby system (E-PT), the west active system (W-WK), the west standby system (W-PT), Insertion (ADD) signals are shown. Further, the output signal further indicates a drop (DROP). In general, an insertion signal is a signal that joins a low-order group to a high-order group network, and a drop is a signal that is output from a high-order group network to a low-order group.

In addition, the insertion signal and the drop signal are combined to connect two BLSRs. That is, when a path is constituted by two BLSRs, a signal dropped by the first BLSR is inserted into the second BLSR. In this case, the terminal relay device that accepts the insertion signal in the second BLSR changes the channel to be relieved from the through signal (E-WK, E-PT, W-WK, or W-PT) to the insertion signal (ADD). ). As described above, the service selector 45 executes a switching process between the through signal and the insertion signal.

  The bridge unit 41 provides the same function as the system block 15-1 on the transmission side in FIG.

  The path switch 46 selects and drops (outputs to the interface to the lower-order group) a channel with a better channel quality (for example, one with no alarm) for the active system and the standby system.

  The cross-connect control code setting units 43 and 44 control the cross-connect processing circuit 42 according to user settings. That is, the cross-connect control code setting units 43 and 44 input an instruction signal for connecting the input-side terminal and the output-side terminal of the cross-connect processing circuit 42 to the cross-connect processing circuit 42.

  The cross-connect control code setting unit 43 selects and assigns either the signal from the east side / the insertion signal to the output channel after the cross-connection. In accordance with this assignment, the cross connect processing circuit 42 cross connects the input side signal and the output side signal.

  The cross-connect control code setting unit 44 performs the same setting for the signal / through signal from the west side. In this way, the circuit of FIG. 24 assigns the signal / insertion signal from the east side and the signal / through signal from the west side independently to the channel after the cross-connect processing.

The alarm detection unit 47 detects an alarm from the main signal. The path switch / service selector processing unit 48 controls the service selector 45 or the path switch 46 according to the alarm detected by the alarm detection unit 47.
<Example 4-1>
FIG. 25 shows the configuration of a terminal relay device according to Embodiment 4-1 of the present invention. As shown in FIG. 25, the terminal relay device employs a configuration in which components other than the cross-connect processing circuit 42 are included in the control system circuit as compared with the case of FIG.

  That is, the control system circuit includes an alarm detection unit 147 that detects an alarm on the main signal, a pass code generation unit 150 that generates a pass code for identifying each signal channel, and a transmission path that transmits the pass code. Switch that switches between the active system and the standby system before cross-connect processing for transmission paths corresponding to higher-order groups (for example, the east active system, the east standby system, the west active system, and the west standby system in the case of BLSR) Unit 140, cross-connect processing circuits 142A and 142B that perform cross-connect processing on a transmission path that transmits a pass code, cross-connect control code setting unit 143 that controls cross-connect processing circuit 142A according to user settings, Cross-connect control for controlling the cross-connect processing circuit 142B according to user settings A service setting unit 144, a service selector 145 for switching between a pass code corresponding to a through signal and a pass code corresponding to an insertion signal, among transmission paths that transmit the pass code after cross-connect processing, The path switch 146 that selects and drops the one with the better line quality (the one that does not generate an alarm) between the transmission path of the active path code and the transmission path of the standby path code, and the path switch / service selector processing Part 148.

  Among these, the pass code generation unit 150 generates a pass code corresponding to the input channel of the main signal. The pass code is a code for individually identifying the input channel of the main signal. For example, in an OC-48 level terminal relay device, a pass code identifying 48 channels is used. Further, in a terminal relay device including 10 sets of OC-48, for example, a pass code identifying 480 channels is used.

The pass code only needs to have a number of bits that can identify these channels. For example, in order to identify 480 channels, it is sufficient to have 9 bits (2 ⁹ = 512).

  The pass code generator 150 generates a code for identifying each of these channels with a bit pattern of a combination of 0 and 1. FIG. 25 illustrates E-WK, E-PT, W-WK, W-PT, and DROP among these channels.

  In the present embodiment, the control system circuit has a transmission path using these bit patterns for each channel. That is, for example, since a terminal relay device with 480 channels requires 9 bits for each channel, a circuit using a total of 4320 bits for all channels is configured.

  The switch unit 140 switches the path of the pass code by selecting the one with the better line quality between the active system and the standby system for this pass code, as in the switch unit 40 of FIG. Alternatively, the switch unit 140 provides the same function as that of the system block 5-1 on the reception side illustrated in FIG. 11 during the BLSR process, and switches the passcode transmission path. The detection result in the alarm detection unit 147 is also switched in the same manner as the passcode.

  The functions of the cross-connect control code setting units 143 and 144 are the same as those of the conventional cross-connect control code setting units 43 and 44 shown in FIG. In the cross-connect processing circuits 142A and 142B, the target of the cross-connect processing is the transmission path of the passcode and the transmission path of the alarm detection result, but the processing content is the same as that of the normal cross-connect processing circuit 42.

  Further, the processing contents of the service selector 145, the path switch 146, and the bridge unit 141 are the same as those of the service selector 45, the path switch 46, and the bridge unit 46 in FIG. 24 except that the processing target is a path transmission path. It is the same.

  For example, the service selector 145 switches between insertion (add) and through for the passcode. Further, the path switch 146 executes a passcode cross-connect process for the east / west.

  The path switch / service selector processing unit 148 generates a switching signal for the service selector 145 and the path switch 146.

  As described above, the control system circuit shown in FIG. 25 performs a cross connect process including a linear ADM or BLSR process on the pass code for identifying the channel of each input signal. Then, the cross connect processing result is output and input to the cross connect processing circuit 42 (signal 151).

This signal 151 has a transmission path with the number of bits for identifying each channel. The transmission path corresponds to the channel on the output side of the cross-connect processing circuit. Therefore, the signal 151 indicates the relationship between the channel after cross-connect and the channel before cross-connect to be cross-connected to the signal. That is, the cross connect processing circuit 42 may convert the channel of the input signal into the channel of the output signal in accordance with the signal 151.

As described above, by executing the cross connect process including the linear ADM or the BLSR process on the signal having the number of bits sufficient to identify the channel, a setting signal for the cross connect processing circuit 42 of the main signal can be obtained. Therefore, in the control system circuit separated from the main signal, a pass code that simulates the main signal is used,
ADM or BLSR processing can be executed.
<Example 4-2>
FIG. 26 shows the configuration of a terminal relay device according to Embodiment 4-2 of the present invention. In Example 4-1 described above, the cross-connect process in which the pass code that simulates the main signal is used and the Linear ADM or BLSR process is substantially executed has been described.

  26 differs from the first embodiment in that the switch unit 40 is included in the main signal system circuit as compared to FIG. 25 of the first embodiment. Other configurations and operations are the same as those in the first embodiment. Therefore, the same components are denoted by the same reference numerals and the description thereof is omitted.

  In the circuit of FIG. 26, the switch unit 40 is used in the main signal system circuit. Therefore, the alarm detection unit 147 may detect an alarm from the main signal after execution of the Linear ADM process. For this reason, it is not necessary to execute the Linear ADM process corresponding to the process of the switch unit 40 on the control system circuit side. Therefore, as compared with the case of FIG. 25, in FIG. 26, the passcode generation unit 150 and the switch unit 140 are excluded from the control system circuit. That is, in the circuit of the second embodiment, the control code of the cross-connect control code setting units 143 and 144 (code indicating which input channel is assigned to the channel after cross-connect) is the service selector 145 and the bridge unit 141, or This is input to the cross-connect processing circuit 42 via the path switch 146.

  As described above, the function of this circuit is the same as that of the circuit of FIG. 25 except that the switch unit 40 is in the main signal system circuit and the passcode generation unit 150 is not provided.

<Other variations>
In the above embodiment, an example in which the present invention is implemented in SONET / SDH has been shown. However, the implementation of the present invention is not limited to SONET / SDH. That is, the present invention can be implemented in general relay apparatuses having a switching function between the active system and the standby system and a cross-connect processing function.
《Industrial applicability》
INDUSTRIAL APPLICABILITY The present invention can be used for a relay apparatus having a switching function between an active system and a standby system and a cross-connect processing function in a network such as SONET / SDH.
<Others>
This embodiment includes the following aspects (referred to as supplementary notes). The configuration included in each supplementary note may be combined with the configuration included in another supplementary note.
(Supplementary note 1) Such a cross-connect processing circuit that executes cross-connect processing including line setting on the network, and an active system that is provided on the input side of the cross-connect processing circuit and that provides a line on the network A plurality of such first transmission line switching units that switch between a transmission line and a backup transmission line that is an alternative transmission line to the working transmission line, and on the output side of the cross-connect processing circuit, on the network A terminal relay apparatus for a network having a plurality of such second transmission path switching units that switch between an active transmission line that provides a line of the current system and a standby transmission line that is an alternative transmission path of the active transmission line The cross-connect processing circuit has a plurality of input side interfaces and a plurality of output side interfaces, and the first transmission path switching unit and the second transmission path Replacement unit each has an input side interface and output interface, the terminal station relay device,
An interface unit to a transmission path on the network or an interface unit to a lower network connected to the network is inserted, and is received by a transmission terminal and a reception terminal on the interface unit to the network or the lower network, A plurality of slot portions,
A first selection unit that selectively connects a receiving terminal on the interface unit inserted into any one of the slot units to an input side interface of the first transmission line switching unit;
A second selection unit for connecting an output side interface of the first transmission line switching unit to an input side interface of the cross-connect processing circuit;
A third selection unit for selectively connecting the output side interface of the cross-connect processing circuit to any one of the input side interfaces of the second transmission line switching unit;
A fourth selection unit that connects an output side interface of the second transmission path switching unit to a transmission terminal on the interface unit that is inserted into any of the slot units;
A terminal relay device comprising:
(Supplementary Note 2) The second selection unit associates the reception terminal connected via the first selection unit and the first transmission path switching unit with a slot position where an interface including the reception terminal is inserted. The terminal relay device according to attachment 1, wherein the terminal relay device is connected to an input side interface of the cross-connect processing circuit.
(Supplementary Note 3) The third selection unit is connected via the second transmission path switching unit and the fourth connection unit, and the slot including the transmission terminal is inserted into the transmission terminal. The terminal relay device according to appendix 1 or 2, connected to an output side interface of the cross-connect processing circuit, which is associated with a position.
(Additional remark 4) It further has the quality judgment part which judges the transmission quality of the said network,
The terminal relay device according to appendix 1, wherein the first transmission path switching unit or the second transmission path switching unit switches between the working transmission line and the standby transmission line according to the transmission quality.
(Supplementary note 5) The terminal relay device according to supplementary note 1, wherein the network is a SONET / SDH optical network.
(Appendix 6) The network has a configuration in which the terminal relay device is connected to another terminal relay device on a one-to-one basis, a configuration in which the terminal relay device is linearly connected to another series of terminal relay devices, or other plural The terminal relay device according to appendix 1, including a configuration in which the terminal relay device is connected in a ring shape.
(Supplementary note 7) The terminal relay device according to supplementary note 1, wherein the terminal relay device constitutes a USPR (Uni-directional Path Switched Ring) in a SONET / SDH optical network.
(Supplementary note 8) The terminal relay device according to supplementary note 1, wherein the terminal relay device constitutes a BLSR (Bi-directional Line Switched Ring) in a SONET / SDH optical network.
(Supplementary Note 9) A first ring transmission line having an active transmission line in the first direction and a standby transmission line in the first direction, an active transmission line in the second direction, and a second direction A terminal relay device connected to a network including a second ring transmission line having a standby transmission line to
Such a cross-connect processing circuit for performing cross-connect processing of communication channels on the network; and
For the cross-connect processing circuit, an active transmission line from the first direction on the receiving side from the network and a standby transmission line from the second direction serving as an alternative transmission line for the active transmission line A plurality of such first transmission line switching units to be switched;
For the cross-connect processing circuit, on the transmission side to the network, an active transmission line in the first direction and a standby transmission line in the second direction serving as an alternative transmission line for the active transmission line; A plurality of such second transmission line switching units,
The first transmission line switching unit includes channel information detection means for identifying a communication channel in communication in the active transmission line;
Channel identification means for identifying a communication channel included in such a standby transmission line, corresponding to the communication channel used in the active transmission line, based on the channel information;
A terminal relay apparatus comprising: a switch unit that switches a communication channel of the working transmission line to a communication channel of a standby transmission line that is identified based on the channel identification unit.
(Additional remark 10) With respect to the cross-connect processing circuit, the standby transmission from the first direction which is on the receiving side from the network and serves as an alternative transmission line for the working transmission line and the working transmission line from the second direction. A plurality of such third transmission line switching units for switching between the paths;
For the cross-connect processing circuit, on the transmission side to the network, an active transmission line in the second direction and a standby transmission line in the first direction serving as an alternative transmission line for the active transmission line; A plurality of such fourth transmission line switching units,
The third transmission line switching unit includes channel information detection means for identifying a communication channel in communication in the working transmission line;
Channel identification means for identifying a communication channel included in such a standby transmission line, corresponding to the communication channel used in the active transmission line, based on the channel information;
The terminal relay device according to appendix 9, further comprising: a switch unit that switches the communication channel of the working transmission line to the communication channel of the standby transmission line identified based on the channel identification unit.
(Supplementary Note 11) In the first ring transmission line, the active transmission line and the standby transmission line have different transmission media, and in the second ring transmission line, the active transmission line and the standby transmission line are The terminal relay device according to appendix 9, each having a different transmission medium.
(Supplementary Note 12) Such a cross-connect processing circuit that executes cross-connect processing including line setting on the network;
A control circuit for controlling the cross-connect processing circuit;
The control circuit includes:
A control transmission line including a plurality of lines corresponding to the transmission line of the network;
A switching unit for switching the line in the control transmission line;
A terminal relay device comprising: a setting unit that sets a correspondence relationship between a line after switching by the switching unit and a line before switching in the cross-connect processing circuit.
(Supplementary note 13) The terminal relay device according to Supplementary note 12, further comprising an identification information generating unit that generates identification information for identifying the line and inputs the identification information to a corresponding line of the control transmission path. (Supplementary note 14) The control transmission line corresponds to a first control transmission line including a plurality of lines corresponding to an active transmission line included in the network, and a standby transmission line included in the network, and The second control transmission line serving as an alternative transmission line of the control transmission line,
The terminal relay device according to appendix 12, wherein the switching unit switches a line between the first control transmission line and the second control transmission line.
(Supplementary Note 15) The control transmission line further includes a third transmission line including a subscriber-side line to the network and a fourth transmission line including a leaving-side line from the network,
The switching unit includes, on the input side to the switching unit, an input-side switching unit that switches a line with the first control transmission line, the second control transmission line, or the third transmission line, and the switching unit. 13. The terminal relay device according to appendix 12, further comprising: an output side switching unit that switches a line with the first control transmission line, the second control transmission line, or the fourth transmission line on the output side.
(Supplementary Note 16) The terminal relay device according to Supplementary Note 14, wherein the terminal relay device constitutes a USPR (Uni-directional Path Switched Ring) in a SONET / SDH optical network.
(Supplementary note 17) The terminal relay device according to supplementary note 14, wherein the terminal relay device constitutes a BLSR (Bi-directional Line Switched Ring) in a SONET / SDH optical network.
(Supplementary Note 18) A first ring transmission line having an active transmission line in the first direction and a standby transmission line in the first direction, an active transmission line in the second direction, and a second direction And a second ring transmission line having a standby transmission line to the network, wherein the network performs such a cross-connect processing circuit for performing a cross-connect process on a communication channel on the network. Have
For the cross-connect processing circuit, on the receiving side from the network, an active transmission line from the first direction and a standby transmission line from the second direction serving as an alternative transmission line for the active transmission line. A first switching step for switching;
With respect to the cross-connect processing circuit, on the transmission side to the network, a working transmission line in the second direction and a standby transmission line in the first direction serving as an alternative transmission line for the working transmission line, A second switching step for switching between
The first switching step includes detecting channel information for identifying a communication channel in communication in the active transmission path;
Holding the channel information;
Identifying a communication channel included in such a standby transmission line corresponding to the communication channel used in the active transmission line based on the channel information;
Switching the communication channel of the working transmission line to the communication channel of the standby transmission line identified based on the channel information.
(Supplementary note 19) On the receiving side from the network with respect to the cross-connect processing circuit, a working transmission line from the second direction and a standby transmission line from the first direction serving as an alternative transmission line of the working transmission line; A plurality of such third transmission line switching steps,
For the cross-connect processing circuit, on the transmission side to the network, the active transmission line in the second direction is switched between the active transmission line in the second direction and the standby transmission line in the first direction that is an alternative transmission line for the active transmission line. A plurality of such fourth transmission line switching steps,
The third transmission line switching step includes:
A step of detecting channel information for identifying a communication channel in communication in the working transmission line;
A channel identification step for identifying a communication channel included in such a standby transmission line corresponding to the communication channel used in the active transmission line based on the channel information;
The relay method according to appendix 18, further comprising a step of switching the communication channel of the working transmission line to the communication channel of the standby transmission line identified based on the channel identification means.

The figure which shows the network of the terminal (1 + 1) structure which concerns on a prior art The figure which shows the network of the Linear ADM structure concerning a prior art The figure which shows the network of a UPSR structure based on a prior art FIG. 2 is a diagram showing a network of OC-48 level 2 fiber BLSR configuration according to the prior art. 1 shows a network of OC-48 level 4 fiber BLSR configuration according to the prior art. Configuration example of a terminal relay device with multiple protection functions An example of the terminal relay device 1 according to the first embodiment of the present invention The figure which shows the example of an application of the terminal (1 + 1) structure by the terminal relay apparatus 1 and 1 The figure which shows the cross-connection process example of the terminal relay apparatus 1 in the example of an application of a terminal (1 + 1) structure Configuration diagram of line switch and line bridge for 1 + 1 Line APS processing in the system block Configuration diagram during BLSR processing in system blocks 5A-1 and 15A-1 of 4-fiber BLSR The figure which shows the procedure (1) which upgrades from UPSR to BLSR in 2nd Embodiment of this invention. The figure which shows the procedure (2) which upgrades from UPSR to BLSR in 2nd Embodiment of this invention. The figure which shows the procedure (3) which upgrades from UPSR to BLSR in 2nd Embodiment of this invention. Diagram showing the upgrade procedure from a linear ADM configuration to a 4-fiber BLSR Detailed procedure for upgrading from Linear ADM configuration to 4-fiber BLSR (1) Detailed procedure for upgrading from Linear ADM configuration to 4-fiber BLSR (1) Detailed procedure for upgrading from Linear ADM configuration to 4-fiber BLSR (2) Detailed procedure for upgrading from Linear ADM configuration to 4-fiber BLSR (2) The figure which shows BLSR which concerns on 3rd Embodiment of this invention. The figure which shows the state where single failure occurred in BLSR An example of multiple failures in BLSR The figure which shows the process example which relieves a multiple fault in BLSR. Internal function block diagram of a circuit that executes path ID detection processing Circuit configuration diagram of path ID comparison unit 123 and time slot control unit 124 The figure which shows the example of the cross-connect process in a conventional terminal relay apparatus, and an active system / standby system switching circuit Configuration diagram of terminal relay device according to embodiment 4-1 of the present invention Configuration of terminal relay device according to embodiment 4-2 of the present invention

Claims (3)

A first ring transmission line having an active transmission line in the first direction and a standby transmission line in the first direction; an active transmission line in the second direction; and a standby system in the second direction. A terminal relay device connected to a network including a second ring transmission line having a transmission line;
Such a cross-connect processing circuit for performing cross-connect processing of communication channels on the network; and
For the cross-connect processing circuit, an active transmission line from the first direction on the receiving side from the network and a standby transmission line from the second direction serving as an alternative transmission line for the active transmission line A first transmission line switching unit for switching;
For the cross-connect processing circuit, on the transmission side to the network, an active transmission line in the first direction and a standby transmission line in the second direction serving as an alternative transmission line for the active transmission line; A second transmission line switching unit for switching between
The first transmission line switching unit detects channel information for identifying a communication channel in communication on the working transmission line, and holds operation so that the channel information detected before the failure is not changed when a failure occurs. Working system detection means for performing
Standby system detecting means for detecting channel information of the standby transmission line when a failure occurs;
Such standby transmission corresponding to the communication channel used in the active transmission line by comparing channel information held in the active detection means with channel information detected by the standby detection means. Channel identification means for identifying a communication channel included in the road;
A terminal relay apparatus comprising: a switch unit that switches a communication channel of the working transmission line to a communication channel of a standby transmission line that is identified based on the channel identification unit.   In the first ring transmission line, the working transmission line and the standby transmission line have different transmission media, and in the second ring transmission line, the working transmission line and the standby transmission line are different. The terminal relay device according to claim 1, comprising: A first ring transmission line having an active transmission line in the first direction and a standby transmission line in the first direction; an active transmission line in the second direction; and a standby system in the second direction. And a second ring transmission line having a transmission line, wherein the network has such a cross-connect processing circuit for performing a cross-connect process on a communication channel on the network. ,
For the cross-connect processing circuit, on the receiving side from the network, an active transmission line from the first direction and a standby transmission line from the second direction serving as an alternative transmission line for the active transmission line. A first switching step for switching;
With respect to the cross-connect processing circuit, on the transmission side to the network, a working transmission line in the second direction and a standby transmission line in the first direction serving as an alternative transmission line for the working transmission line, A second switching step for switching between
In the first switching step, channel information for identifying a communication channel in communication on the active transmission path is detected, and when a failure occurs, a holding operation is performed so that the channel information detected before the failure is not changed. An active system detection step;
A standby system detection step for detecting channel information of the standby transmission path when a failure occurs,
Such a standby system corresponding to the communication channel used in the active transmission line by comparing the channel information held in the active system detection step with the channel information detected in the standby system detection step. Identifying a communication channel included in the transmission path;
Switching the communication channel of the working transmission line to the communication channel of the standby transmission line identified based on the channel information.

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