JP5975159B2 - Station side apparatus, station side apparatus control method, and optical communication system - Google Patents

Description

  The present invention relates to a station-side device used in an optical communication system, a control method for the station-side device, and an optical communication system.

  In recent years, the Internet has become widespread, and users can access various information on sites operated in various parts of the world and obtain the information. Along with this, devices capable of broadband access such as ADSL (Asymmetric Digital Subscriber Line) and FTTH (Fiber To The Home) are rapidly spreading.

  In business network services, system redundancy (redundancy) is required to provide high-quality services. Also in the audio / video distribution service, a highly reliable system can be provided by the duplex system. In the redundant system, a redundant configuration is adopted in which each of the devices, components, and network has an active system and a standby system as required. When a failure occurs in a part of the operating system, it is possible to make the system stop time due to the failure as short as possible by performing redundant switching from the active system to the standby system.

  Even if a failure has not become apparent, the module may be replaced proactively in consideration of the deterioration tendency of characteristics, the life of parts, and the like. If the system has a redundant configuration for the module, it is possible to shorten the system stop time due to such maintenance work as much as possible.

  For example, Japanese Patent Application Laid-Open No. 2010-147801 (Patent Document 1) discloses an operational OSU (Optical Subscriber Unit) in an OLT (Optical Line Terminal) of a PON (Passive Optical Network) having a redundant configuration. ) Discloses a technology related to switching from a communication path using a) to a communication path using a standby OSU. According to the configuration described in Patent Document 1, the communication path is switched by the optical switch. A certain amount of time is required until the switching destination path is stabilized. For this reason, when the communication path is switched by the optical switch without stopping the transmission of the communication signal, the communication signal passing through the path is discarded until the switching destination path is stabilized. In order to solve this problem, the station-side device disclosed in Patent Document 1 uses an optical switch so that the optical switch does not receive uplink communication signals from a plurality of home-side devices during switching of communication paths by the optical switch. The switch switching timing and the transmission timings of a plurality of home devices are controlled.

JP 2010-147801 A

  Generally, in order to manage a network, a system called NMS (Network Management System) is introduced into the network. The NMS monitors the network and, for example, detects a traffic failure or manages performance.

  In the case of a PON, an ONU (Optical Network Unit; home side device) installed at a subscriber's home is registered in the NMS in association with a PON line. The station side device exchanges information about the ONU with the NMS.

  For example, the NMS instructs the station side device to specify an ONU in association with a PON line, and to set information on the ONU or reference the ONU. In this case, the OSU that terminates the designated PON line is specified inside the station side device. The OSU searches for the designated PON line and sets or references information to the control unit that controls the PON line.

  Alternatively, the station side device notifies the maintenance management information of each ONU to the NMS. In this case, the OSU collects information about ONUs connected to the PON line to be managed. The station side device notifies the NMS of the collected information.

  In the PON line information managed by the NMS, the combination of each PON line and OSU is uniquely fixed. As a result, the NMS can logically identify a plurality of PON lines. On the other hand, like the technique described in Patent Document 1, a configuration is proposed in which there can be a plurality of actual combinations of PON lines and OSUs in the station apparatus. In such a configuration, there may occur a case where the association information between the PON line and the OSU managed by the NMS does not match the actual combination of the PON line and the OSU.

  If the information associated with the PON line and the OSU managed by the NMS does not match the actual combination of the PON line and the OSU, the following problem is considered to occur. The first problem is that the station side device cannot refer to the setting or status for the ONU specified by the NMS. The second problem is that even if a certain OSU generates notification information related to an ONU, if the combination of the OSU and the PON line is different from the information registered in advance in the NMS, the station side device transmits to the NMS. That information cannot be notified.

  In the case of the configuration of the station side device disclosed in Patent Document 1, it is considered that the interface between the switching source OSU and the PON line is completely mapped to the switching destination OSU. On the other hand, Patent Document 1 does not specifically describe the interface between the NMS and the station side device. Therefore, according to the technique of Patent Document 1, the above-described problem may occur. Patent Document 1 does not specifically describe a solution to the problem in the case where the association information between the PON line and the OSU does not match between the NMS and the station side device.

  An object of the present invention is to provide an interface between a station-side device and the outside of the station-side device in an optical communication network including a station-side device having a configuration in which there can be a plurality of combinations of passive optical networks and optical line units. Is to match.

  A station-side apparatus according to an aspect of the present invention is a station-side apparatus that accommodates at least one passive optical network, and a plurality of the other of the passive optical network and the optical line unit are optical. The optical line unit is optically connected between at least one optical line unit provided corresponding to the passive optical network and between the optical line unit and the outside of the station side device so as to be connectable. A station control unit that relays and transmits management information related to management of a passive optical network, and mapping information. The mapping information defines a mapping between a logical line defined by the original combination of optical line unit and passive optical network and a real line indicating the current combination of optical line unit and passive optical network. The station control unit transmits management information associated with the logical line to the outside of the station side device. The optical line unit acquires management information associated with the actual line. The station side device mutually converts the line associated with the management information between the logical line and the actual line using the mapping information.

  According to this configuration, for example, when a logical line is designated from the outside of the station side device to the station side device, the station side device can acquire management information on the actual line corresponding to the logical line. Further, for example, when management information to be notified to the outside of the station side device is generated, the station side device can output the management information in association with a logical line. Therefore, in an optical communication network including a station side device having a configuration in which there can be a plurality of combinations of passive optical networks and optical line units, the interface between the station side device and the outside of the station side device can be matched. it can.

  “A plurality of other optical connections to one of the passive optical network and the optical line unit can be optically connected” means that there are a plurality of optical line units connectable to one passive optical network. It can include both that a plurality of passive optical networks can be connected to the optical line unit. The former is a configuration corresponding to the redundant function, and the latter is a configuration corresponding to the degenerate function.

  The transmission direction of “management information” is not particularly limited. The direction from the outside of the station side device to the station side device, the direction from the station side device to the outside of the station side device, and both of these directions are included in “transmission of management information”. The type of management information is not particularly limited. Further, the type of management information transmitted may be different between the direction from the outside of the station side device to the station side device and the direction from the station side device to the outside of the station side device.

  It is sufficient that the line associated with the management information is converted between the logical line and the actual line using the mapping information by the station side device, and the conversion is performed in a specific component of the station side device. It is not limited to be executed.

  The mapping information may be held by an element (for example, a station control unit or an optical line unit) having a function of performing conversion between a logical line and a real line, or may be held separately from the element. For example, the station-side device may further include a storage unit that stores mapping information. The station control unit or the optical line unit may refer to the mapping information stored in the storage unit.

  Preferably, when the management information to be sent to the outside of the station side device is received from the optical line unit, the station control unit associates the logical line with the management information based on the mapping information, and associates the logical information with the logical line. Output management information.

  According to this configuration, the management information to be sent to the outside of the station side device can be output by being linked to the logical line by the station control unit of the station side device. Therefore, the interface between the station side device and the outside of the station side device can be matched. The conditions for generating management information to be sent to the outside of the station side device are not particularly limited. For example, the station side device may generate management information in response to a request from the outside, or may generate management information in response to a change in state in a passive optical network connected to the optical line unit. Good.

  Preferably, when the station control unit requests acquisition of management information related to the passive optical network designated by the logical line from the outside of the station side apparatus, the station control unit responds to the actual optical corresponding to the logical line based on the mapping information. A line unit is specified, management information is acquired from the actual optical line unit, and the management information is linked to a logical line and output.

  According to this configuration, it is possible to acquire management information corresponding to a logical line designated from the outside of the station side device, and to output the management information linked to the designated logical line. Therefore, the interface between the station side device and the outside of the station side device can be matched.

  Preferably, the optical line unit associates a logical line with the management information acquired by the optical line unit based on the mapping information.

  According to this configuration, the management information is linked to the logical line in the optical line unit. The station control unit outputs management information associated with the logical line to the outside. Therefore, the interface between the station side device and the outside of the station side device can be matched.

  Preferably, when acquisition of management information related to the passive optical network is requested from the outside of the station side device, the optical line unit acquires the management information in response to the request, and based on the mapping information, the management information A logical line is linked to.

  According to this configuration, it is possible to output management information associated with a logical line in response to a request from the outside of the station side device. A method for transmitting a request from the outside of the station side device to the optical line unit from which management information is to be acquired is not particularly limited. When the optical line unit corresponding to the logical line specified by the request from the outside of the station side device matches the optical line unit corresponding to the actual line, for example, the station control unit sends a request from the outside of the station side device. It is sufficient to transmit directly to the optical line unit. When the optical line unit corresponding to the logical line specified by the request from the outside of the station side device is different from the optical line unit corresponding to the actual line, for example, the station control unit changes to the optical line unit corresponding to the logical line. Communicate that request. The optical line unit corresponding to the logical line can transfer the request to the optical line unit corresponding to the actual line.

  Preferably, one of the passive optical network and the optical line unit is a passive optical network. The at least one optical line unit is a plurality of optical line units including a backup optical line unit. The station side device further includes an optical switch for switching a communication path between the passive optical network and the optical line unit. The station control unit controls the optical switch and updates the mapping information.

  According to this configuration, there are a plurality of optical line units that can be connected to one passive optical network. That is, the station side device has a redundancy function. In the station side device having such a redundancy function, the interface between the station side device and the outside of the station side device can be matched.

  Preferably, one of the passive optical network and the optical line unit is an optical line unit. The at least one passive optical network includes first and second passive optical networks. The at least one optical line unit includes a degenerate unit connected to the first and second passive optical networks. The degenerate system unit includes a first optical transceiver that can be optically connected to the first passive optical network, a second optical transceiver that can be optically connected to the second passive optical network, and a first passive unit. A first access control unit capable of executing normal line control, which is uplink multiple access control for an optical network, and degenerate control, which is uplink multiple access control for first and second passive optical networks, and a second passive A second access control unit capable of executing normal line control, which is uplink multiple access control for a general optical network, an upper switch provided on the upper side of the first and second access control units, and first and second And controlling the lower switch, the upper switch and the lower switch provided between the first access controller and the first and second optical transmitter / receivers to perform normal line control and degeneration control. Ri replaced and a degeneration control unit. Either the station control unit or the degeneration control unit updates the mapping information when executing the degeneration control.

  According to this configuration, there are a plurality (at least two) of optical line units connectable to one optical line unit. That is, the station side device has a degeneration function. In the station side device having such a degeneration function, the interface between the station side device and the outside of the station side device can be matched.

  A station-side device control method according to another aspect of the present invention is a station-side device control method that accommodates at least one passive optical network, and includes either a passive optical network or an optical line unit. The present invention relates to management of a passive optical network that is optically connected to the optical line unit in at least one optical line unit provided corresponding to the passive optical network so that a plurality of the other can be optically connected. Mapping between the step of obtaining management information and a logical line defined by the original combination of optical line unit and passive optical network and a real line indicating the current combination of optical line unit and passive optical network To refer to the mapping information that defines the management information, and to manage the logical line specified based on the mapping information In association, and a step of outputting the management information associated with the logical line to an external line terminal.

  According to this configuration, in an optical communication network including a station side device having a configuration in which a plurality of combinations of a passive optical network and an optical line unit can be provided, an interface between the station side device and the outside of the station side device Can be matched.

  An optical communication system according to still another aspect of the present invention includes at least one passive optical network, a plurality of home devices connected to each of the passive optical networks, a passive optical network, and an optical line unit. Any one of a station side device including at least one optical line unit and a plurality of home side devices provided corresponding to a passive optical network so that a plurality of the other can be optically connected to one of them And a management device that acquires management information related to the designated home-side device from the station-side device. The management apparatus designates the home-side apparatus using a logical line defined by the original combination of the optical line unit and the passive optical network. The station side device retains mapping information defining mapping between the logical line and the actual line indicating the current combination of the optical line unit and the passive optical network, and stores the management information obtained based on the mapping information. The logical line is linked, and the management information linked to the logical line is transmitted to the management apparatus.

  According to this configuration, in an optical communication network including a station side device having a configuration in which a plurality of combinations of a passive optical network and an optical line unit can be provided, an interface between the station side device and the outside of the station side device Can be matched. Therefore, the management device can identify the home side device using the logical line and manage the home side device without depending on the internal configuration of the station side device.

  According to the present invention, an interface between an external device such as an NMS and a station-side device can be matched in an optical communication network in which there can be a plurality of combinations of passive optical networks and optical line units.

It is a block diagram which shows schematic structure of the station side apparatus which concerns on the 1st Embodiment of this invention. It is a figure which shows the structural example of the optical switch 11a. It is a block diagram which shows the structural example of OSU. 3 is a block diagram illustrating a configuration example of a control unit 14. FIG. It is a figure for demonstrating the example of the identification information of ONU memorize | stored inside NMS. It is a sequence diagram for demonstrating the response of the station side apparatus when there exists an inquiry from NMS at the time of normal operation. It is a sequence diagram for demonstrating the process of the station side apparatus when the information which should be notified to NMS occurs at the time of normal operation. It is a 1st figure for demonstrating the subject which may arise by switching from the active system OSU to the standby system OSU. FIG. 10 is a second diagram for explaining a problem that may occur due to switching from the active OSU to the standby OSU. It is a figure for demonstrating the content of the table at the time of normal operation. It is a figure for demonstrating the content of the table at the time of redundant operation. It is the flowchart which showed the update process of the mapping table by the control part of a station side apparatus. It is the flowchart which showed the process in which the control part of the station side apparatus which concerns on 1st Embodiment responds to the inquiry of NMS. It is the flowchart which showed the process for the control part of the station side apparatus which concerns on 1st Embodiment to notify the state of ONU to NMS. FIG. 10 is a sequence diagram for explaining a response of the station-side device according to the first embodiment when an inquiry is made from the NMS after switching from the active OSU to the standby OSU. It is a sequence diagram for demonstrating the process of the station side apparatus which concerns on 1st Embodiment, when the information which should be notified to NMS after switching from active OSU to standby OSU occurs. It is a block diagram which shows schematic structure of the station side apparatus which concerns on the 2nd Embodiment of this invention. It is a block diagram which shows the structure of OSU12a shown by FIG. It is a figure which shows the flow of the communication frame in the normal operation | movement of the station side apparatus which concerns on 2nd Embodiment. It is a figure which shows the flow of the normal flame | frame in the case of concentrating access control to the system | strain A side in the degeneracy operation | movement of the station side apparatus which concerns on 2nd Embodiment. It is a sequence diagram for demonstrating the response of the station side apparatus which concerns on 2nd Embodiment in case there exists an inquiry from NMS in degeneration operation | movement. It is a sequence diagram for demonstrating the process of the station side apparatus which concerns on 2nd Embodiment when the information which should be notified to NMS generate | occur | produces in degeneration operation | movement. It is a figure for demonstrating the content of the table at the time of normal operation | movement. It is a figure for demonstrating the content of the table at the time of degeneration operation | movement. It is the flowchart which showed the process in which the control part of the station side apparatus which concerns on 2nd Embodiment responds to the inquiry of NMS. It is the flowchart which showed the process for the control part of the station side apparatus which concerns on 2nd Embodiment to notify the information of ONU to NMS. It is the flowchart which showed another process in which the control part of the station side apparatus which concerns on 2nd Embodiment responds to the inquiry of NMS. It is the flowchart which showed another process for the control part of the station side apparatus which concerns on 2nd Embodiment to notify the information of ONU to NMS.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals and description thereof will not be repeated. Also, it is assumed that the PON shown in the following embodiment is an Ethernet (registered trademark) -based PON (EPON).

[Embodiment 1]
FIG. 1 is a block diagram showing a schematic configuration of a station-side apparatus according to the first embodiment of the present invention. Referring to FIG. 1, a PON system 301 includes a station side device (OLT) 1a, N PON lines 1 to N (3-1 to 3-N) as optical fibers, and N optical couplers 4. -1 to 4-N, a plurality of home-side devices (ONUs) 2, and a network management system (NMS) 5.

  The station side device 1a includes an optical switch 11a, OSU1 to N + 1 (12-1 to 12-N + 1), a concentrator 13a, and a control unit 14 that performs overall control of the station side device 1a. In this embodiment, N is an integer greater than or equal to 2. The “control unit 14” realizes a “station control unit” included in the station side apparatus according to the present invention.

  The station apparatus 1a is connected to N PON lines 1 to N and accommodates the N PON lines. The PON lines 1 to N are connected to the optical couplers 4-1 to 4-N, respectively, and are connected to a plurality of ONUs 2 through these optical couplers.

  The station side device 1a has a redundant configuration. That is, out of N + 1 OSUs 12, OSU1 to N are active (active) OSUs, and OSU N + 1 is a standby (standby) OSU. The station side device 1a may include two or more standby OSUs. When an abnormality occurs in any active OSU, the standby OSU terminates the PON line associated with the active OSU.

  The optical switch 11a is connected between the N + 1 OSU1 to N + 1 (12-1 to 12-N + 1) and the N PON lines 1 to N (3-1 to 3-N) according to an instruction from the control unit 14. Switch the communication path.

  The concentrator 13a multiplexes the uplink frames from the OSU1 to N + 1 (12-1 to 12-N + 1) and transmits them to the upper network (hereinafter also referred to as uplink). Furthermore, the line concentrator 13a distributes the downlink frame received from the uplink to an appropriate OSU.

  The NMS 5 is realized by hardware, software, or a combination thereof. In the network management system 5, the PON line and the ONU 2 connected to the PON line are registered. The ONU registration includes, for example, settings such as identification information (for example, serial number) for recognizing individual ONUs, quality of service, network parameters, and the like. The NMS 5 manages each ONU 2 and provides various services to each ONU 2. For example, the NMS 5 performs various settings for each ONU 2 through the station apparatus 1a. Or NMS5 acquires the information regarding the state of each ONU2 through the station | side apparatus 1a.

  When the network administrator registers an ONU installed at the subscriber's home in the NMS 5, the ONU is registered in association with the PON line. Further, in the NMS 5, each of the PON lines 1 to N is registered in association with the active OSU and 1 to N in a 1: 1 relationship. Therefore, the NMS 5 identifies each of the PON lines 1 to N by a combination of the active OSU and the PON line. A communication path that is logically identified by the original combination between the active OSU and the PON line is defined as a “logical line” in this specification. That is, the NMS 5 holds logical line information.

  On the other hand, the combination of the OSU and the PON line can change inside the station apparatus 1a. That is, there are a plurality of OSUs that can be optically connected to one PON line (active OSU and standby OSU). In this specification, a communication path determined by an actual combination of an OSU and a PON line (that is, a combination at the present time) is defined as “real line”. In this embodiment, there may be both cases where the logical line and the real line match and when the logical line and the real line are different.

  In the configuration shown in FIG. 1, the number of PON lines connected to one OSU is one. However, a plurality of PON lines may be connected to one OSU. In the following, the first embodiment will be described based on a configuration in which one PON line is connected to one OSU.

  FIG. 2 is a diagram illustrating a configuration example of the optical switch 11a. Referring to FIG. 2, in optical switch 11a, N optical fibers on the PON side and N optical fibers on the OSU side are arranged to face each other. Hereinafter, these N sets of optical fibers are also referred to as operational optical fibers.

  Collimator lenses 23-1 to 23-N are arranged near the end face of each optical fiber on the OSU side. Collimator lenses 24-1 to 24-N are arranged near the end face of each optical fiber on the PON line side. In a normal state, optical space transmission is performed between facing optical fibers. N optical axes of the N sets of operational optical fibers are arranged to be parallel on the same plane.

  The movable mirror 22 is driven by the actuator 21 and moves on an axis orthogonal to the optical axis of the N PON lines (optical fibers) 3-1 to 3-N. The movable mirror 22 is located at any of the intersections of the N optical axes of the operational optical fiber and the moving axis of the movable mirror 22 and in the vicinity of the end face of the standby optical fiber. The actuator 21 moves the movable mirror 22 to one of the (N + 1) positions according to a control signal from the control unit 14. The control signal from the control unit 14 indicates the presence / absence of OSU redundancy switching and the number of the PON line connected to the standby OSU. The actuator 21 moves the movable mirror 22 based on this control signal.

  The movable mirror 22 is inclined by 45 ° with respect to the optical axis of the operational optical fiber, and reflects the light beam from the optical fiber on the PON line side in the moving axis direction of the movable mirror 22. The light beam reflected by the movable mirror 22 enters the standby optical fiber 3-N + 1 via the collimator lens 23-N + 1.

  The light beam from the standby optical fiber 3-N + 1 is reflected by the movable mirror 22 and is incident on the optical fiber on the PON line side corresponding to the position of the movable mirror 22. Therefore, optical space transmission can be performed between the optical fiber on the PON line side corresponding to the position of the movable mirror 22 and the standby optical fiber 3-N + 1.

  When the movable mirror 22 is moved, the movable mirror 22 is once shifted in the z direction (the direction from the front to the back in FIG. 2) and then moved in the x direction. By such a method, it is possible to prevent the movement of the movable mirror 22 from affecting the optical space transmission between the optical fiber pairs that are irrelevant to the switching among the opposed optical fiber pairs.

FIG. 3 is a block diagram illustrating a configuration example of the OSU. Referring to FIG. 3, OSU 12 includes a concentrator IF (Interface) unit 31, a control IF unit 32, a reception processing unit 33, and a transmission processing unit 34.
A PON transmitting / receiving unit 35, a local control unit 36, a FIFO1 (37) for accumulating upstream frames, and a FIFO2 (38) for accumulating downstream frames.

  The PON transmission / reception unit 35 is connected to the optical switch 11a by an optical fiber. The PON transmission / reception unit 35 receives an upstream optical signal of a specific wavelength, for example, a 1310 nm band, converts the optical signal into an electrical signal, and outputs the electrical signal to the reception processing unit 33. On the other hand, the PON transmission / reception unit 35 converts the electrical signal output from the transmission processing unit 34 into a downstream optical signal of another wavelength, for example, a 1490 nm band, and transmits the optical signal. Thereby, bidirectional communication can be performed in one optical fiber.

  The reception processing unit 33 reconstructs a frame from the electrical signal received from the PON transmission / reception unit 35 and distributes the frame to the control IF unit 32, the local control unit 36, or the FIFO 1 (37) according to the type of the frame. Specifically, the reception processing unit 33 outputs a user frame to the FIFO 1 (37), outputs a special control frame such as a loopback test to the local control unit 36, and transmits other general control frames to the control IF unit 32. Output to.

  The reception processing unit 33 receives grant information indicating when to receive a frame from which logical link from the transmission processing unit 34, and filters a received frame that is not indicated in the grant information, that is, discards the received frame. Also good. The reception processing unit 33 may output the MPCP frame by overwriting the time stamp at the time of reception.

  The concentration IF unit 31 sends the upstream frame stored in the FIFO 1 (37) to the concentration unit 13a and stores the downstream frame received from the concentration unit 13a in the FIFO 2 (38). At this time, the concentrating IF unit 31 performs conversion between the signal format of the concentrating unit 13a and the internal signal format.

  When the FIFO 2 (38), the control IF unit 32, or the local control unit 36 has a frame / message to be transmitted, the transmission processing unit 34 receives the frame / message according to the priority order, assembles the frame, and sends it to the PON transmission / reception unit 35. Output. At this time, the time stamp at the time of transmission may be overwritten on the MPCP frame and output. In addition, the transmission processing unit 34 outputs the grant information described in the gate message from the control IF unit 32 to the reception processing unit 33.

  The control IF unit 32 outputs the control message received from the reception processing unit 33 to the control unit 14 and outputs the control message received from the control unit 14 to the transmission processing unit 34. At this time, the control IF unit 32 performs conversion between the signal format of the control unit 14 and the internal signal format.

  Basically, the control unit 14 terminates the control protocol for managing and operating the PON. However, the local control unit 36 may terminate a specific protocol in order to reduce the processing load on the control unit 14.

  The transmission processing unit 34 collects statistical information such as the number of transmission frames and notifies the control unit 14 via the control IF unit 32.

  Similarly, the reception processing unit 33 collects statistical information such as the number of received frames and the number of received signal code errors and notifies the control unit 14 via the control IF unit 32. This statistical information is used when determining switching of the system in a configuration in which the OSU is made redundant. For example, when there is a large number of code errors in the received signal in a certain operating OSU, control such as switching from the OSU to the standby OSU is performed.

  Further, the PON transceiver unit 35 monitors its own transmission light level. When the transmitted light level is out of the specified range due to a failure and the aging deterioration of the light emitting element, the PON transmission / reception unit 35 notifies the control unit 14 of an alarm via the control IF unit 32.

  FIG. 4 is a block diagram illustrating a configuration example of the control unit 14. Referring to FIG. 4, the control unit 14 includes a CPU (Central Processing Unit) 51, a ROM (Read Only Memory) 52, a RAM (Random Access Memory) 53, an IO (Input Output) control unit 54, an OSU. An IF unit 55, a shared RAM 56, and a clock / timer 57 are included.

  The OSU IF unit 55 is connected to the OSUs 1 to N + 1 (12-1 to 12-N + 1), and is transmitted / received to / from the ONU, and the OSU for managing and controlling the OSU. Send and receive information via message communication. These messages are transmitted / received to / from the CPU 51 via the input message queue and the output message queue included in the shared RAM 56.

  In response to a command from the CPU 51, the IO control unit 54 performs setting and state management of the concentrator 13a and the optical switch 11a. Further, the IO control unit 54 communicates information related to maintenance or management of the PON line and ONU (hereinafter also referred to as “management information”) with the NMS 5. As described above, information about logical lines is registered in the NMS 5. Therefore, the IO control unit 54 transmits ONU management information to and from the NMS 5 using this logical line information.

  Furthermore, the IO control unit 54 provides an operator with an operation interface (hereinafter also referred to as an operation IF) of the station side device 1a. Further, when receiving an event such as a response or an alarm from the NMS 5, the operation IF, the line concentrator 13a, and the optical switch 11a, the IO control unit 54 notifies the CPU 51 as an interrupt.

  The clock / timer 57 manages a clock and various timers for managing the PON, and outputs a time and timer end interrupt to the CPU 51.

  The ROM 52 stores a program for controlling the entire control unit 14 and fixed data. The RAM 53 is used as a work area for temporarily storing data.

  The CPU 51 reads and executes a program from the ROM 52, and reads out fixed data stored in the ROM 52 and reads / writes data to / from the RAM 53 to execute processing described later.

  The reference clock for driving the PON clock is also given to each OSU, and the PON clock of each OSU is synchronized with the periodic time notification by management communication.

  FIG. 5 is a diagram for explaining an example of ONU identification information stored in the NMS. Referring to FIG. 5, an OSU number, a PON line number, an ONU serial number, and an SLA (Service Level Agreement) are stored as ONU identification information.

  The OSU number is a number for identifying the operating OSUs 1 to N (OSUs 12-1 to 12-N). Each OSU number is associated with a PON line number. In this embodiment, one PON line is optically connected to one active OSU. Therefore, one PON line number is associated with one OSU number. In a configuration in which a plurality of PON lines are optically connected to one operational OSU, a plurality of PON line numbers are associated with one OSU number. A communication path defined by a combination of an OSU number and a PON line number corresponds to a “logical line”.

  The ONU serial number is a number for identifying an ONU connected to one PON line. The SLA indicates the content or quality of the service negotiated between the service provider and the service user. As shown in FIG. 5, a level such as “Normal” or “Premium” is set according to the content or quality of the contracted service.

  FIG. 6 is a sequence diagram for explaining the response of the station side device when an inquiry is received from the NMS during normal operation. Referring to FIG. 6, during normal operation, OSUs 1 to N are optically connected to PON lines 1 to N by optical switch 11 a (hereinafter referred to as “optical connection”). Through the steps (1) to (4) described below, the station side device 1a responds to an inquiry from the NMS. In FIG. 6, broken-line arrows labeled “(1)” to “(4)” indicate information flows corresponding to the following steps (1) to (4).

  The NMS 5 requests the control unit 14 to obtain management information indicating the state of the ONU 2 identified by the OSU 1 -PON line 1 -serial number AAA (step (1)). The control unit 14 requests the OSU 1 (OSU 12-1) to obtain information regarding the state of the ONU 2 identified by the PON line 1-serial number AAA (step (2)). The OSU 1 (OUS12-1) generates information on the state of the ONU 2 identified by the serial number AAA among the plurality of ONUs 2 connected to the PON line 1 (PON line 3-1), and uses the information as a control unit 14 (step (3)). The control unit 14 transmits the information acquired from the OSU 1 to the NMS 5 (Step (4)).

  FIG. 7 is a sequence diagram for explaining processing of the station side apparatus when information to be notified to the NMS occurs during normal operation. Referring to FIG. 7, management information indicating the state of the ONU is issued from ONU 2 (serial number AAA) connected to PON line 1 of OSU 1. This management information is, for example, an alarm indicating an ONU abnormality (step (1)). The alarm is sent to OSU 1 (step (2)). The OSU 1 notifies the control unit 14 that an alarm has been issued from the ONU 2 (serial number AAA) connected to the PON line 1 (step (3)). The control unit 14 notifies the NMS 5 of an alarm of the OSU1-PON line 1-ONU (serial number AAA) (step (4)). As shown in FIG. 6 and FIG. 7, the control unit 14 manages information regarding management of the PON line 1 optically connected to the OSU 1 between the OSU 1 and the NMS 5, that is, the ONU 2 connected to the PON line 1. Relay management information of The management information is linked to the actual line.

  During normal operation, the actual line matches the logical line managed by the NMS. Therefore, even if the management information is associated with a real line, the management information can be transmitted between the station side device 1a and the NMS 5. However, in this embodiment, the station side device has a redundancy function. When an abnormality occurs in the active OSU that terminates a certain PON line, the OSU that terminates the PON line is changed to a standby OSU. In this case, a real line that does not match the logical line is generated. Therefore, the following problems may occur.

  FIG. 8 is a first diagram for explaining a problem that may be caused by switching from the active OSU to the standby OSU. Referring to FIG. 8, it is assumed that a failure has occurred in OSU1. In this case, the optical switch 11a switches the OSU optically connected to the PON line 1 from OSU1 to OSUN + 1.

  As in the example of FIG. 6, the NMS 5 requests the control unit 14 to obtain management information indicating the state of the ONU 2 identified by the OSU1-PON line 1-serial number AAA (step (1)). The control unit 14 requests the OSU 1 (OSU 12-1) to obtain management information indicating the state of the ONU 2 identified by the PON line 1-serial number AAA (step (2)). However, the PON line 1 is not optically connected to the OSU 1. For this reason, the OSU 1 cannot transmit the management information of the ONU 2 identified by the serial number AAA to the control unit 14. Therefore, the control unit 14 cannot execute the processing of step (3) and step (4) shown in FIG.

  FIG. 9 is a second diagram for explaining a problem that may occur due to switching from the active OSU to the standby OSU. Referring to FIG. 9, ONU 2 (serial number AAA) connected to OSUN + 1 PON line 1 generates an alarm (step (1)). Since a failure has occurred in OSU1, PON line 1 is optically connected to OSUN + 1. Therefore, the alarm is sent to OSUN + 1 (step (2)).

  The control unit 14 receives an alarm from OSUN + 1. However, the combination of OSUN + 1 and PON line 1 is not registered as a logical line. Therefore, the control unit 14 cannot send management information that is not associated with a logical line to the NMS 5.

  In order to solve the problems shown in FIGS. 8 and 9, the control unit 14 stores mapping information for mapping the logical line and the real line. In this embodiment, the mapping information is stored in the RAM 53 of the control unit 14 in the form of a table, for example. When changing the communication path between the OSU and the PON line, the control unit 14 controls the optical switch 11a and updates this table. By updating the table, the mapping information between the logical line and the actual line is updated.

  FIG. 10 is a diagram for explaining the contents of the table during normal operation. FIG. 11 is a diagram for explaining the contents of the table during redundant operation. Referring to FIG. 10 and FIG. 11, the logical line and the actual line match during normal operation. On the other hand, during the redundant operation, for example, the PON line connected to the active OSU1 is switched to be connected to the standby ONUN + 1. In this case, the table is updated and the actual lines (OSU1-PON lines 1 to M) are associated with the logical lines (OSU1-PON lines 1 to M).

  FIG. 12 is a flowchart showing mapping table update processing by the control unit of the station side device. The processing shown in FIG. 12 is executed at a constant cycle, for example. With reference to FIG. 12, in step S1, the control unit 14 determines whether or not the optical connection between the OSU and the PON line has changed. “Optical connection change” includes, but is not limited to, switching the optical connection of the PON line from the active OSU to the standby OSU. The case where the optical connection of the PON line is switched from the standby OSU to the active OSU can be included in the “optical connection change”.

  When there is a change in the optical connection between the PON line and the OSU (YES in step S1), in step S2, the control unit 14 updates the table. If there is no change in the optical connection between the PON line and the OSU (NO in step S1), the process in step S2 is skipped. Therefore, the table is not updated.

  FIG. 13 is a flowchart illustrating a process in which the control unit of the station-side apparatus according to the first embodiment responds to an NMS inquiry. Referring to FIG. 13, in step S11, control unit 14 receives a request from the NMS. In step S12, the control unit 14 refers to the table. In step S13, the control unit 14 determines a real line corresponding to the logical line designated by the NMS based on the table, and determines an OSU corresponding to the real line.

  In step S14, the control unit 14 designates the PON line and ONU to the corresponding OSU and requests acquisition of management information of the ONU. In step S15, the control unit 14 acquires information (that is, management information) regarding the state of the ONU through the OSU. In step S16, the control unit 14 converts (maps) the actual line associated with the management information into a logical line. The control unit 14 may execute this process with reference to the table. Or the control part 14 may perform the process of step S16 based on the information of the table referred in step S12. In step S <b> 17, the control unit 14 transmits ONU management information associated with the logical line to the NMS 5.

  FIG. 14 is a flowchart showing a process for the control unit of the station side apparatus according to the first embodiment to notify the NMS of the ONU state. Referring to FIG. 14, in step S21, control unit 14 receives a notification from OSU. The OSU receives information from the ONU through a PON line connected to the OSU. This information is transmitted to the control unit 14 as a notification from the OSU. The notification from the OSU includes, but is not limited to, an alarm issued from the ONU.

  In step S22, the control unit 14 refers to the table and converts the actual line into a logical line. In step S <b> 23, the control unit 14 transmits information about the ONU associated with the logical line to the NMS 5.

  FIG. 15 is a sequence diagram for explaining a response of the station side apparatus according to the first embodiment when there is an inquiry from the NMS after switching from the active OSU to the standby OSU. Referring to FIG. 15, reference signs “S11” to “S17” indicate processing of corresponding steps shown in FIG. 13.

  The NMS 5 requests the control unit 14 to acquire information related to the state of the ONU 2 identified by the OSU 1 -PON line 1 -serial number AAA (step S 11). Next, the control unit 14 refers to the table and confirms that OSU1 in the logical line corresponds to OSUN + 1 in the real line (steps S12 and S13). The control unit 14 requests OSUN + 1 to obtain information on the state of the ONU 2 identified by the PON line 1-serial number AAA (step S14).

  OSUN + 1 returns to the control unit 14 information related to the state of the ONU 2 identified by the serial number AAA among the plurality of ONUs 2 connected to the PON line 1 (PON line 3-1). As a result, the control unit 14 acquires management information of the designated ONU 2 (step S15).

  The management information acquired by the control unit 14 is linked to the actual line (OSUN + 1-PON line 1). Therefore, the control unit 14 converts OSUN + 1 in the actual line into the corresponding logical line OSU (that is, OSU1) (step S16). The control unit 14 transmits the management information of the ONU 2 associated with the logical line (OSU1-PON line 1) to the NMS 5 (step S17).

  FIG. 16 is a sequence diagram for explaining processing of the station side apparatus according to the first embodiment when information to be notified to the NMS occurs after switching from the active OSU to the standby OSU. Referring to FIG. 16, reference numerals “S21” to “S23” indicate processes of corresponding steps shown in FIG.

  First, the PON line 1 is optically connected to OSUN + 1. An ONU (serial number AAA) connected to the PON line 1 generates an alarm. The alarm is sent to OSUN + 1 through the PON line 1. The control unit 14 receives an alarm from OSUN + 1 (step S21). This alarm is linked to the actual line (OSUN + 1-PON line 1). The control unit 14 refers to the table and converts OSUN + 1 in the actual line into the corresponding logical line OSU (that is, OSU1) (step S22). The control unit 14 transmits an alarm for the ONU 2 associated with the logical line (OSU1-PON line 1) to the NMS 5 (step S23).

  As described above, according to the first embodiment, in the station side device having a redundancy function, the line associated with the ONU management information is mutually converted (mapped) between the logical line and the actual line. To do. As a result, the interface between the station side device and the outside of the station side device can be matched.

  The NMS can identify an ONU using a logical line and manage the ONU without depending on the internal configuration of the station side device. As described above, the NMS can make various settings for the ONU and receive notifications from the ONU. Thereby, the NMS can provide various services to the ONU via the station side device.

[Embodiment 2]
The station side apparatus according to the first embodiment has a redundancy function. The station side apparatus according to the second embodiment has a degeneration function.

  FIG. 17 is a block diagram showing a schematic configuration of a station side apparatus according to the second embodiment of the present invention. Referring to FIGS. 1 and 17, the PON system 302 includes a station side device 1b instead of the station side device 1a. The station side apparatus 1b is different from the station side apparatus 1a in that the optical switch 11a is omitted and the OSUs 12a-1 to 12-N are provided instead of the OSUs 12-1 to 12-N + 1.

  The OSU 12a-1 is connected to M (M; an integer of 2 or more) PON lines. That is, the OSU 12a-1 is a degenerate system unit. It is not necessary to limit the OSUs 12a-1 to 12-N to be all degenerate units. For example, at least one of the OSUs 12a-1 to 12-N may be a degenerate unit, and one PON line may be optically connected to the remaining OSUs. In the configuration shown in FIG. 17, the number of PON lines connected to OSUN is one. Such a configuration is also included in this embodiment.

  FIG. 18 is a block diagram showing the configuration of the OSU 12a shown in FIG. Referring to FIG. 18, for the sake of simplicity, it is assumed that only two PON lines are optically connected to OSU 12a. The OSU 12a includes an upper switch 61, access control units 62A and 62B, a management unit 63, a lower switch 64, an optical transmission / reception control unit 65, and optical transmission / reception units 66A and 66B. In the following, as an expression for distinguishing the system composed of the PON line 3-1, the access control unit 62A and the optical transmission / reception unit 66A from the system composed of the PON line 3-2, the access control unit 62B and the optical transmission / reception unit 66B, A ”and“ System B ”may be used.

  The upper switch 61 includes an L2 switch connected to the upper side of the access control units 62A and 62B. The upper switch 61 multiplexes the uplink frames transmitted from the access control units 62A and 62B and relays them to the uplink (upper network). Furthermore, the upper switch 61 relays the downstream frame from the uplink to the PON lines 3-1 and 3-2 to each of the access control units 62A and 62B. When the downstream frame is a unicast frame, the upper switch 61 separates the downstream frame. If the downstream frame is not a unicast frame, the upper switch 61 copies the downstream frame as necessary. Note that the upper switch 61 can also return a downlink frame from the uplink to the uplink or return an uplink frame from the access control units 62A and 62B to the access control units 62A and 62B.

  The management unit 63 performs management of the OSU 12a and management of the ONU 2 via the access control units 62A and 62B. The management unit 63 includes a management interface 69 and a degeneration control unit 70. The management interface 69 is connected to the control unit 14. The management interface 69 can receive a command from the NMS 5 via the control unit 14.

  The degeneration control unit 70 performs switching of the upper switch 61 and switching of the lower switch 64 via the optical transmission / reception control unit 65 based on an input signal from the management interface 69. The lower switch 64 includes an L1 switch. The lower switch 64 is connected between the access control units 62A and 62B and the optical transmission / reception units 66A and 66B. The lower switch 64 has a function of switching the electrical signal path between the access control units 62A and 62B and the optical transmission / reception units 66A and 66B at the physical layer level.

  The access control unit 62A includes an upper side transmission unit 72, an upper side reception unit 73, a relay processing unit 74, an LLID (Logical Link ID) management table 75, a PON control unit 76, a PON side reception unit 77, A PON side transmitter 78. The downstream frame input from the upper switch 61 is received by the upper receiving unit 73 and sent to the relay processing unit 74. The relay processing unit 74 sends the downstream frame to the PON side transmission unit 78. The PON side transmitter 78 inputs the downstream frame to the lower switch 64.

  The upstream frame input from the lower switch 64 is received by the PON side receiving unit 77 and sent to the relay processing unit 74 or the PON control unit 76. If the upstream frame is a data frame, the PON side receiving unit 77 passes it to the relay processing unit 74. If the upstream frame is a control frame such as an MPCP frame or an OAM frame, the PON side receiving unit 77 passes it to the PON control unit 76. The relay processing unit 74 sends the data frame to the higher-level transmission unit 72. The upper PON control unit 76 performs predetermined processing according to the nature of the control frame received from the PON side receiving unit 77.

  The optical transceiver 66A is configured by a known optical transceiver. The optical transceiver 66A includes an optical receiver 80, an optical transmitter 81, and a multiplexing / demultiplexing unit 82. The upstream optical signal from the PON line 3-1 is received by the optical receiving unit 80 through the multiplexing / demultiplexing unit 82. The optical receiver 80 converts the received upstream optical signal into an electrical signal and inputs the electrical signal to the lower switch 64. The downstream electrical signal from the lower switch 64 is converted into an optical signal by the optical transmitter 81. The downstream optical signal is sent to the PON line 3-1 through the multiplexing / demultiplexing unit 82.

  The configuration of the access control unit 62B is the same as the configuration of the access control unit 62A. The configuration of the optical transceiver 66B is the same as the configuration of the optical transceiver 66A. Accordingly, the description of the configuration of the access control unit 62B and the optical transmission / reception unit 66B will not be repeated.

  The degeneration control unit 70 outputs a control signal for switching the upper switch 61 to the upper switch 61 and also outputs a control signal for switching the lower switch 64 to the optical transmission / reception control unit 65 based on a command from the control unit 14. To do.

  FIG. 19 is a diagram illustrating a communication frame flow in the normal operation of the station-side apparatus according to the second embodiment. FIG. 20 is a diagram illustrating a normal frame flow when the access control is concentrated on the system A side in the degeneration operation of the station side apparatus according to the second embodiment. Hereinafter, the contents of the switch control performed by the degeneration control unit 70 will be described with reference to FIGS. 19 and 20.

  When the command received from the management interface 69 indicates “normal operation”, the degeneration control unit 70 determines the output destination of the downstream frame to the PON lines 3-1 and 3-2 input to the upper switch 61 as access control. The parts 62A and 62B are dispersed. Further, the degeneration control unit 70 sets the output destinations of the downlink frames input to the lower switch 64 from the access control units 62A and 62B in the optical transmission / reception units 66A and 66B, respectively. Further, the degeneration control unit 70 sets the output destinations of the upstream frames input from the optical transmission / reception units 66A and 66B to the lower switch 64 in the access control units 62A and 62B, respectively.

  Next, a case where the command received from the management interface 69 indicates degeneration control that concentrates access on the system A side will be described. The output destinations of the downstream frames to the PON lines 3-1 and 3-2 input to the upper switch 61 are concentrated on the access control unit 62A. Further, the degeneration control unit 70 distributes the output destinations of the downlink frames input from the access control unit 62A to the lower switch 64 to the optical transmission / reception units 66A and 66B. Further, the degeneration control unit 70 performs time-division multiplexing control on the lower switch 64 and concentrates the output destinations of the upstream frames input from the optical transmission / reception units 66A and 66B to the lower switch 64 in the access control unit 62A. The lower switch 64 inputs the upstream frame from the optical receiver 80 of the optical transceivers 66A and 66B to the PON side receiver 77 of the access controller 62A by time division multiplexing.

  When the command received from the management interface 69 indicates degeneration control that concentrates access on the system B side, the degeneration control unit 70 controls the access control unit 62B to perform the same control as that described above for the access control unit 62A. Run against. Therefore, detailed description of the control in this case will not be repeated.

  When the number of PON lines connectable to one OSU is three or more, the OSU only needs to have the same number of optical transmission / reception units and access control units as the PON line. Since the operation at the time of degeneration control in this case is the same as the operation shown in FIG. 20, the following description will not be repeated.

  FIG. 21 is a sequence diagram for explaining the response of the station side apparatus according to the second embodiment when there is an inquiry from the NMS in the degeneration operation. Referring to FIG. 21, OSU 1 degenerates PON line 1 to PON line M. In other words, access is concentrated in the access control unit corresponding to the PON line M in the OSU 1.

  The NMS 5 requests the control unit 14 to obtain information regarding the state of the ONU 2 identified by the OSU 1 -PON line 1 -serial number AAA (step (1)). The control unit 14 requests the OSU 1 (OSU 12-1) to acquire information regarding the state of the ONU 2 identified by the PON line 1-serial number AAA (step (2)).

  In the OSU 1, the degeneration control unit 70 returns information related to the state of the ONU 2 identified by the serial number AAA among the plurality of ONUs 2 connected to the PON line 1 (PON line 3-1) to the control unit 14. (Step (3)).

The control unit 14 transmits the information acquired from the OSU 1 to the NMS 5 (Step (4)).
FIG. 22 is a sequence diagram for explaining processing of the station side apparatus according to the second embodiment when information to be notified to the NMS is generated in the degeneration operation. Referring to FIG. 22, PON line 1 is degenerated to PON line M in OSU 1. Also in this case, access is concentrated in the access control unit corresponding to the PON line M within the OSU 1.

  The ONU (serial number AAA) connected to the PON line 1 of the OSU 1 generates an alarm (step (1)). The alarm is sent to the OSU 1 through the PON line 1 (step (2)). Inside the OSU 1, the degeneration control unit 70 notifies the control unit 14 that an alarm has been issued from the ONU 2 with the serial number AAA connected to the PON line 1 (step (3)). The control unit 14 notifies the NMS 5 of the alarm as an ONU alarm of the OSU1-PON line 1-serial number AAA (step (4)).

  In OSU1, since the PON line 1 is degenerated to the PON line M, a difference occurs between the logical line designated by the NMS and the actual line. Therefore, as in the first embodiment, a table for mapping logical lines and actual lines is also used in the second embodiment.

  FIG. 23 is a diagram for explaining the contents of the table during normal operation. FIG. 24 is a diagram for explaining the contents of the table during the degeneration operation. Referring to FIG. 23 and FIG. 24, the logical line and the actual line are coincident during normal operation. During the degeneration operation, for example, in the OSU 1, access control for a plurality of PON lines is concentrated on the access control unit corresponding to the PON line M. The PON line “1M” shown in FIG. 24 indicates that the PON line 1 and the access control unit of the PON line M are combined in the degeneration operation. Similarly, the PON line “MM” indicates that the PON line M and the access control unit of the PON line M are combined in the degeneration operation. Thus, in this embodiment, the actual line during the degeneration operation can be defined by the PON line and the access control unit that concentrates access control.

  According to one configuration according to this embodiment, the control unit 14 holds the table. According to another configuration, each of the OSUs 1 to N holds a table. In the latter case, each OSU only needs to hold a table indicating the mapping between the logical line corresponding to itself and the actual line. For example, the OSU 1 may hold the mapping associated with the OSU 1 in the table shown in FIG. In this case, the degeneration control unit 70 of the OSU 1 holds the table. Hereinafter, processing executed by each configuration will be described.

(Configuration in which the control unit 14 holds the table)
FIG. 25 is a flowchart illustrating a process in which the control unit of the station-side apparatus according to the second embodiment responds to an NMS inquiry. Referring to FIG. 25, in step S31, control unit 14 receives a request from the NMS. In step S32, the control unit 14 refers to the table. In step S33, the control unit 14 determines a real line corresponding to the logical line designated by the NMS based on the table, and determines an OSU and a PON line corresponding to the real line. For example, when “OSU1-PON line 1” is designated as the logical line during the degeneration operation, the control unit 14 refers to the table to determine the corresponding real line (for example, “OSU1-PON line 1M”). .

  In step S34, the control unit 14 requests the corresponding OSU to acquire ONU2 information. In step S35, the control unit 14 acquires management information related to the ONU2 through the OSU. This management information is linked to the actual line. In step S36, the control unit 14 converts (maps) the actual line (OSU1-PON line 1M) associated with the management information into a logical line (OSU1-PON line 1). In step S <b> 37, the control unit 14 transmits information on the ONU 2 associated with the logical line to the NMS 5.

  FIG. 26 is a flowchart showing a process for the control unit of the station side apparatus according to the second embodiment to notify the NMS of ONU information. Referring to FIG. 26, in step S41, control unit 14 receives a notification from OSU. This notification includes an alarm issued from the ONU 2, but is not limited to this.

  In step S42, the control unit 14 refers to the table and converts the actual line (OSU1-PON line 1M) associated with the alarm into a logical line (OSU1-PON line 1). In step S <b> 43, the control unit 14 transmits an alarm (that is, information on the ONU 2) associated with the logical line to the NMS 5.

(Configuration in which each OSU holds a table)
FIG. 27 is a flowchart illustrating another process in which the control unit of the station-side apparatus according to the second embodiment responds to an NMS inquiry. Referring to FIG. 27, in step S51, control unit 14 receives a request from the NMS. In step S52, the control unit 14 requests the OSU corresponding to the logical line designated by the NMS to obtain the ONU 2 information. For example, when “OSU1-PON line 1” is designated as the logical line, the control unit 14 instructs the OSU 1 to acquire information on the ONU 2 connected to the PON line 1.

  In step S53, the corresponding OSU (OSU1 in the above example) refers to the table. In step S54, the OSU determines a PON line (for example, PON line 1) corresponding to the logical line designated by the NMS 5 based on the table. In step S55, the OSU (degeneration control unit 70) acquires information about the ONU 2 through an access control unit (for example, an access control unit of the PON line M) corresponding to the PON line.

  In step S56, the OSU converts the actual line (OSU1-PON line 1M) into a logical line (OSU1-PON line 1), associates the information of ONU2 with the logical line, and transmits the information to the control unit 14. In step S57, the control unit 14 transmits information about the ONU 2 to the NMS 5. Therefore, ONU 2 information is transmitted between the control unit 14 and the NMS 5 using a logical line.

  FIG. 28 is a flowchart showing another process for the control unit of the station side apparatus according to the second embodiment to notify the NMS of ONU information. Referring to FIG. 28, in step S61, the OSU (for example, OSU1) receives a notification from ONU2. This notification includes an alarm issued from the ONU 2, but is not limited to this.

  In step S62, the OSU refers to the table and associates the logical line (OSU1-PON line 1) with the alarm information. In step S <b> 63, the OSU transmits information about the ONU 2 associated with the logical line to the control unit 14. In step S <b> 64, the control unit 14 transmits information on the ONU 2 to the NMS 5. Therefore, ONU 2 information is transmitted between the control unit 14 and the NMS 5 using a logical line.

  As described above, according to the second embodiment, the logical line and the real line are mutually converted (mapped) in the station side device having the degeneration function. This mapping can be executed by either the control unit 14 (station control unit) or the OSU degeneration control unit. As a result, the interface between the station side device and the outside of the station side device can be matched. As in the first embodiment, the NMS can identify a target ONU using a logical line and manage the ONU without depending on the internal configuration of the station side device. Therefore, the NMS can provide various services to the ONU via the station side device.

  Also in the first embodiment, a logical line may be associated with management information in the OSU. For example, when the control unit 14 (station control unit) receives a request from the NMS 5, the control unit 14 transmits this request to the OSU corresponding to the logical line. When the logical line matches the actual line, the OSU that has received the request acquires management information and links the logical line to the management information based on the mapping information. When the logical line and the actual line are different (that is, when the OSU optically connected to a certain PON line is switched from the active OSU to the standby OSU), the standby OSU is managed as follows. A logical line can be linked to information. First, an OSU (active OSU) corresponding to a logical line receives a request from the NMS 5 via the control unit 14. Next, the active OSU transfers the request from the control unit 14 to the OSU (standby OSU) corresponding to the actual line. The standby OSU acquires management information from the PON line, and links a logical line to the management information based on the mapping information. The standby OSU transmits management information to the control unit 14.

  Similarly, when information to be notified to the NMS is generated, the OSU (active OSU or standby OSU) that has received the information associates a logical line with the management information based on the mapping information. The OSU transmits management information associated with the logical line to the control unit 14.

  In such a configuration, for example, the active OSU can hold a table as shown in FIG. When an OSU that is optically connected to a certain PON line is switched from the active OSU to the standby OSU, the active OSU updates its table to update the actual line information corresponding to itself to the new ( Change to real line information after switching. The table may be updated by the control unit 14 or the active OSU. The updated table is the same as the table shown in FIG. The active OSU may transfer the updated table to the standby OSU.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  1a, 1b Station side device, 2 home side device (ONU), 3-1 to 3-N PON line, 4-1 to 4-N optical fiber, 5 network management system (NMS), 11a optical switch, 12-1 -12-N + 1, 12a-1 to 12a-N Optical line unit (OSU), 13a Concentrator, 14 Controller, 21 Actuator, 22 Movable mirror, 23-1 to 23-N + 1, 241-1 to 24-N Collimate Lens, 31 Concentration IF unit, 32 Control IF unit, 33 Reception processing unit, 34 Transmission processing unit, 35 PON transmission / reception unit, 36 Local control unit, 37 FIFO1, 38 FIFO2, 51 CPU, 52 ROM, 53 RAM, 54 IO control Unit, 55 OSU IF unit, 56 shared RAM, 57 clock / timer, 61 host switch, 62A, 62B access control Unit, 63 management unit, 64 lower switch, 65 optical transmission / reception control unit, 66A, 66B optical transmission / reception unit, 69 management interface, 70 degeneration control unit, 72 upper side transmission unit, 73 upper side reception unit, 74 relay processing unit, 75 LLID management table, 76 PON control unit, 77 PON side receiving unit, 78 PON side transmitting unit, 80 optical receiving unit, 81 optical transmitting unit, 82 multiplexing / demultiplexing unit, 301, 302 PON system.

Claims (9)

A station-side device accommodating at least one passive optical network,
At least one of the optical line units provided corresponding to the passive optical network so that a plurality of the other can be optically connected to one of the passive optical network and the optical line unit; ,
A station controller that relays and transmits management information related to management of a passive optical network optically connected to the optical line unit between the optical line unit and the outside of the station side device;
Defined a mapping between a logical line defined by the original combination of the optical line unit and the passive optical network and a real line indicating the current combination of the optical line unit and the passive optical network Mapping information,
The station control unit communicates the management information associated with the logical line with the outside of the station side device,
The optical line unit acquires the management information associated with the real line,
The station-side apparatus, a line tied to the management information, and converts mutually between the actual line and the logical line using the mapping information,
The station side device reflects the change of the optical connection in the mapping information when the optical connection between the passive optical network and the optical line unit is changed .   The station control unit receives the management information to be sent to the outside of the station side device from the optical line unit, associates the logical line with the management information based on the mapping information, and connects the logical line to the logical line. The station-side apparatus according to claim 1, wherein the associated management information is output.   The station control unit, when requested to obtain the management information related to the passive optical network specified by the logical line from the outside of the station side device, to the logical line based on the mapping information The station according to claim 1, wherein a corresponding actual optical line unit is specified, the management information is acquired from the actual optical line unit, and the management information is linked to the logical line and output. Side device.   The station-side apparatus according to claim 1, wherein the optical line unit associates the logical line with the management information acquired by the optical line unit based on the mapping information.   When acquisition of the management information related to the passive optical network is requested from the outside of the station side device, the optical line unit acquires the management information in response to the request, and adds the management information to the mapping information. The station apparatus according to claim 1 or 4, wherein the logical line is linked to the management information based on the management information. The one of the passive optical network and the optical line unit is the passive optical network;
The at least one optical line unit is a plurality of optical line units including a backup optical line unit;
The station side device further includes an optical switch that switches a communication path between the passive optical network and the optical line unit,
The station-side device according to claim 1, wherein the station control unit controls the optical switch and updates the mapping information. The one of the passive optical network and the optical line unit is the optical line unit;
The at least one passive optical network includes first and second passive optical networks;
The at least one optical line unit includes a degenerate unit connected to the first and second passive optical networks;
The degenerate system unit is
A first optical transceiver that is optically connectable to the first passive optical network;
A second optical transceiver that is optically connectable to the second passive optical network;
First access capable of executing normal line control, which is uplink multiple access control for the first passive optical network, and degeneracy control, which is uplink uplink access control for the first and second passive optical networks A control unit;
A second access control unit capable of executing normal line control which is the uplink multiple access control for the second passive optical network;
An upper switch provided on an upper side of the first and second access control units;
A lower switch provided between the first and second access control units and the first and second optical transceiver units;
6. The station-side apparatus according to claim 1, further comprising: a degeneration control unit that controls the upper switch and the lower switch to switch between the normal line control and the degeneration control. A control method of a station side device accommodating at least one passive optical network,
In at least one of the optical line units provided corresponding to the passive optical network, such that a plurality of the other can be optically connected to one of the passive optical network and the optical line unit. Obtaining management information relating to management of a passive optical network optically connected to the optical line unit;
A mapping defining a mapping between a logical line defined by the original combination of the optical line unit and the passive optical network and a real line indicating a current combination of the optical line unit and the passive optical network A step of referring to the information;
Associating a logical line identified based on the mapping information with the management information, and outputting the management information associated with the logical line to the outside of the station side device ;
And a step of reflecting the change of the optical connection in the mapping information when there is a change in the optical connection between the passive optical network and the optical line unit . At least one passive optical network;
A plurality of home-side devices connected to the passive optical network;
At least one of the optical line units provided corresponding to the passive optical network is provided so that a plurality of the other can be optically connected to one of the passive optical network and the optical line unit. Including station side devices,
A management device that acquires management information related to the designated home-side device from the station-side device by designating any of the plurality of home-side devices to the station-side device;
The management device designates the home device using a logical line defined by an original combination of the optical line unit and the passive optical network,
The station side device holds mapping information defining mapping between the logical line and a real line indicating a current combination of the optical line unit and the passive optical network, and based on the mapping information, Link the logical line to the acquired management information, send the management information linked to the logical line to the management device, and change to an optical connection between the passive optical network and the optical line unit When there is, an optical communication system that reflects the change in the optical connection in the mapping information .

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