JP5026467B2 - COMMUNICATION MONITORING DEVICE, COMMUNICATION MONITORING METHOD, AND PROGRAM - Google Patents

Description

  The present invention relates to a communication monitoring device, a communication monitoring method, and a program in an optical access network system.

  When relocating an optical fiber cable in relocation work due to factors such as road construction, it is necessary to cut the existing optical fiber cable and reconnect it to the newly laid optical fiber cable. Also, in the replacement work of the optical fiber cable, it is necessary to similarly cut the existing optical fiber cable and reconnect it to the replacement optical fiber cable. In such an optical fiber cable switching work, since the optical fiber in the optical fiber cable is temporarily cut, the service may be interrupted even though the user is using the service.

  Since interruption during use of the service by the user leads to deterioration in service quality, it is preferable that when the optical fiber is cut, it can be determined whether or not the user is using the service. If the usage status of the user's service is known, it is possible to postpone the switching work of the optical fiber in which the user is using the service, or to perform the flexible switching work according to the service usage status of the user. Therefore, since the switching work can be performed without interrupting the service, the service quality is greatly improved. Therefore, a communication monitoring device that monitors the traffic of the optical access network and monitors the service usage status of the user is desired.

  Hereinafter, the optical access network will be described. As shown in FIG. 1, in the media converter (MC) method, one optical subscriber terminal (OLT) 3 is connected to one optical network terminal (ONU) 2 and an optical fiber. It is a network that performs point-to-point communication through the network. The communication terminal 1 used by the user can receive a service from the backbone network via the OLT 3 via the ONU 2. Further, as shown in FIG. 2, the passive optical network (PON) system is configured by using a plurality of ONUs 2-N in which one OLT 3 is connected to each communication terminal 1-N, an optical fiber, and a 1 to N optical splitter 4. Network that performs point-to-multipoint communication (N is a natural number).

  As an MC and PON standard, Gigabit Ethernet (registered trademark) defined in IEEE 802.3 is used. Note that EPON (Ethernet (registered trademark) Passive Optical Network) is standardized as a standard for Gigabit Ethernet (registered trademark) corresponding to PON. In EPON, since signals transmitted from a plurality of ONUs are shared by the optical fiber ahead of the splitter, a protocol (MPCP) that controls the transmission timing of signals is avoided so as to avoid collision of signals transmitted from different ONUs. It prescribes. Here, in order to control the transmission timing, a MAC frame that is used only in the EPON section is called an MPCP frame, and a MAC frame that is used outside the EPON section is called a data frame. Also, EPON assigns LLID (Logical Link ID) to each ONU to identify a plurality of ONUs, and performs transmission / reception control of MAC frames in units of LLIDs. The LLID is given to the preamble of the MAC frame exchanged in the EPON section.

  As shown in FIG. 3, the optical access network system includes an MC system, a PON system, an intra-station optical fiber termination 5 and a service multiplexer / demultiplexer 6. Each of the plurality of communication terminals is represented as 1-N, each of the plurality of ONUs is represented as 2-N, and each of the plurality of OLTs is represented as 3-N. The optical fiber termination 5 collects the optical fiber from each OLT3-N and the optical fiber extending outside the office. Here, the MC system and the PON system are mixedly accommodated in the optical fiber termination 5. Further, each optical coupler 5-N for an optical pulse test (OTDR: Optical Time-Domain Reflectometer) 7 is connected to each optical fiber. The service multiplexer / demultiplexer 6 collects optical fibers extending from the respective OLTs 3-N and connects them to the backbone network. The service multiplexer / demultiplexer 6 has a mirroring port, and the traffic flowing through the MC type or PON type optical fiber can be monitored via this mirroring port.

  Hereinafter, a conventional communication monitoring method will be described.

  As a first communication monitoring method, the traffic for each communication terminal 1-N can be monitored by connecting a protocol analyzer functioning as a communication monitoring device to the mirroring port of the service demultiplexing device 6 (for example, non-communication). Patent Document 1). However, since it is impossible to identify which OLT3-N and which ONU2-N the traffic flows from, it is necessary to specify the optical fiber that the user is using the service in the optical fiber switching work. I can't.

  As a second communication monitoring method, if an optical tester or an optical power meter is connected to the optical coupler 5-N for OTDR 7 in the optical fiber termination 5, it is possible to determine the presence or absence of an optical signal for each optical fiber. . However, it is impossible to determine whether or not the user is actually using the service only by the presence or absence of the optical signal.

  As a third communication monitoring method, the conventional MC communication monitoring device 8 is connected to the MC optical fiber through the optical coupler 5-N of the optical fiber termination 5 and monitors the traffic flowing through the MC optical fiber. be able to. As shown in FIG. 4, the conventional MC communication monitoring device 8 includes an optical receiver 81, an MC signal processing function unit 82, and a display function unit 83. The optical receiver 81 receives an optical signal of Gigabit Ethernet (registered trademark) via the optical coupler 5-N for OTDR7. The MC signal processing function unit 82 performs frame processing on the received signal received by the optical receiver 81 and collects traffic information (count of the number of frames and contents of the frames). The display function unit 83 can display the collected traffic information on a predetermined display screen of the MC communication monitoring device 8 (see, for example, Non-Patent Document 1).

  As a fourth communication monitoring method, the conventional PON communication monitoring device 9 is connected to a PON type optical fiber via the optical coupler 5-N of the optical fiber termination 5 and traffic flowing through the PON type optical fiber is transmitted. Can be monitored. As shown in FIG. 5, the conventional PON communication monitoring device 9 includes an optical receiver 91, a PON signal processing function unit 92, and a display function unit 93. The optical receiver 91 receives an optical signal of Gigabit Ethernet (registered trademark) via the optical coupler 5-N for OTDR7. The PON signal processing function unit 92 processes the received signal received by the optical receiver 91 as a MAC frame for PON, and collects MPCP frames and traffic information for each LLID assigned to the ONU 2-N. The display function unit 93 displays the collected traffic information on a predetermined display screen of the communication monitoring device 9 (see, for example, Patent Document 1).

JP 2007-96847 A

“EtherScope NetWork Assistant VLAN / Switch Network Troubleshooting”, Fluke Networks, 2005

  Such a conventional communication monitoring method can see the amount of traffic flowing through the optical access network and the contents of the traffic. However, the conventional communication monitoring devices 8 and 9 have a function of determining whether a link between the OLT and the ONU is established for each ONU, or a function of identifying which service is being used. Absent. Furthermore, since the optical fiber termination 5 may accommodate both the MC method and the PON method, if the optical access network is accommodated in which optical fiber in advance, the communication monitoring device 8 or It is difficult to easily identify whether the optical access network to which the communication monitoring device 9 is connected is communication based on the MC system or communication based on the PON system.

  That is, it is desirable for the communication monitoring apparatus to have the following functions.

  First, it is possible to automatically determine whether the optical access network connected to the optical fiber is an MC or a PON.

  Secondly, the connection state (that is, the link state) between the ONU and the OLT in the optical access network system can be confirmed for each ONU. A MAC address is used as identification information for each ONU.

  Third, in the optical access network, it is possible to determine whether or not communication is being performed for each service.

  An object of the present invention is made in view of these problems, and is to provide a communication monitoring device, a communication monitoring method, and a program in an optical access network system.

  Unlike the conventional MC and PON communication monitoring apparatus, the communication monitoring apparatus of the present invention further includes a signal type identification unit and a PON / MC communication monitoring unit. Thereby, it is possible to determine whether the connection destination of the communication monitoring apparatus of the present invention is an MC optical fiber or a PON optical fiber. Further, the communication monitoring device of the present invention grasps the usage status of each service and displays it on a predetermined display screen in the communication monitoring device of the present invention if the connection destination of the communication monitoring device of the present invention is an MC type optical fiber. However, if it is a PON type optical fiber, the usage status of each service for each ONU can be grasped and displayed on a predetermined display screen in the communication monitoring apparatus of the present invention.

  That is, the communication monitoring apparatus of the present invention is a communication state of an optical access network system in which one or more optical subscriber termination devices (OLT) and one or more optical network termination devices (ONU) are connected via an optical fiber. Monitoring apparatus for monitoring an upstream optical signal from an ONU to an OLT via an optical coupler on an optical fiber transmission line, and receiving from the received signal received by the optical signal receiving means A signal type identifying means for automatically discriminating whether the communication is based on MC or PON based on the preamble difference in the MAC frame in the signal, and according to the signal type determined by the signal type identifying means And a communication monitoring means for monitoring the communication state in the MC system or the communication state in the PON system.

  In the communication monitoring apparatus of the present invention, when the communication monitoring unit determines whether the communication is based on the MC method or the communication based on the PON method by the signal type identification unit, Data representing the link establishment between the ONU and the OLT and the communication state of each priority is generated.

  In the communication monitoring apparatus of the present invention, when the communication monitoring unit determines whether the communication is based on the MC method or the communication based on the PON method by the signal type identification unit, the communication monitoring unit is a communication based on the PON method. Data representing the establishment of each link between the ONU and the OLT and the communication state of each priority for each ONU is generated.

  The communication monitoring apparatus according to the present invention further includes display means for displaying the generated data on a predetermined display screen.

  Further, in the communication monitoring apparatus of the present invention, the signal type identification unit determines that the signal is in a connected state when continuously receiving a giga idle signal for more than a prescribed bit within a certain time, and continuously receives more than the prescribed bit. If not, it is determined that it is not connected.

  The communication monitoring apparatus of the present invention further includes a PON signal processing means for processing a PON frame of the received signal, and the PON signal when the signal type identifying means determines that the communication is based on the PON system. When the PON frame is an MPCP frame, the processing means reads the LLID and the source address from the MPCP frame, identifies the corresponding ONU, associates the LLID with the source address, and sets the MPCP for each LLID. A function of counting frames within a predetermined time, and the communication monitoring unit determines that the number of MPCP frames of the PON frame is equal to or greater than a predetermined threshold when the signal type identification unit determines that the communication is based on the PON method. Is determined to be equal to or greater than the predetermined threshold. When the communication is in progress, it is determined that the communication is in progress, the state of link establishment between each ONU and the ONU is determined, and whether the communication is being performed for each LLID and priority. It sends out to a display means, It is characterized by the above-mentioned.

  The communication monitoring apparatus of the present invention further includes a PON signal processing means for processing a PON frame of the received signal, and the PON signal when the signal type identifying means determines that the communication is based on the PON system. As the frame processing, when the PON frame is a data frame, the processing means reads the user priority bits (priority) of the LLID and VLAN from the data frame, and counts the data frame for each LLID and priority within a certain time. And the communication monitoring means compares whether the number of data frames in the PON frame is equal to or greater than a predetermined threshold when the signal type identification means determines that the communication is based on the PON method. And determining that the communication is in progress when it is determined that the predetermined threshold value is exceeded, The state of the link establishment between the NU different OLT and ONU, determines whether communication is in progress for each LLID and priority, and wherein the sending the result of the determination on the display means.

  Further, the communication monitoring apparatus of the present invention further comprises MC signal processing means for performing frame processing on the MC frame of the received signal, and the MC signal when the signal type identifying means determines that the communication is based on the MC system. The processing means has a function of reading a VLAN user priority bit (priority) from the data frame of the MC frame as frame processing, and counting the data frame within a predetermined time for each priority, and the communication monitoring means When the signal type identification means determines that the communication is based on the MC method, the number of data frames in the MC frame is compared with a predetermined threshold value, and is determined to be equal to or higher than the predetermined threshold value. When determining, it is determined that communication is in progress, and the status of link establishment between the OLT and the ONU, and each priority It is determined whether or not in communication, and wherein the sending the result of the determination on the display means.

  Furthermore, the communication monitoring method of the present invention is a communication state of an optical access network system in which one or more optical subscriber termination units (OLT) and one or more optical network termination units (ONU) are connected via an optical fiber. A method of monitoring an upstream optical signal from the ONU to the OLT via an optical coupler on an optical fiber transmission line, and a MAC in a received signal from the received signal received in the step A step of automatically determining whether the communication is based on the MC method or the communication based on the PON method based on the difference in the preamble in the frame, and depending on the signal type determined in the step, the communication state in the MC method or the PON method And a step of monitoring a communication state.

  Further, the present invention provides communication for monitoring a communication state of an optical access network system in which one or more optical subscriber termination units (OLT) and one or more optical network termination units (ONU) are connected via an optical fiber. A computer configured as a monitoring device receives an upstream optical signal from the ONU to the OLT via an optical coupler on an optical fiber transmission line, and from the received signal received in the step, in a MAC frame in the received signal A step of automatically determining whether the communication is based on MC or PON based on the preamble difference between the communication method in the MC method or the communication in the PON based on the signal type determined in the step It is also characterized as a program for executing the step of monitoring the condition.

  According to the communication monitoring apparatus, the communication monitoring method, and the program of the present invention, the optical access network connected to the optical fiber is automatically recognized regardless of whether the communication is based on the MC system or the communication based on the PON system. Can be discriminated.

  In addition, according to the communication monitoring apparatus and the communication monitoring method of the present invention, the connection state (that is, the link state) between the ONU and the OLT of the optical access network system can be confirmed for each ONU.

1 is a diagram illustrating a media converter (MC) type network in which one optical subscriber termination unit (OLT) performs point-to-point communication with one optical network termination unit (ONU) via an optical fiber. FIG. FIG. 2 is a diagram illustrating a passive optical network (PON) network in which one OLT performs point-to-multipoint communication via a plurality of ONUs, optical fibers, and 1 to n optical splitters (n is a natural number). It is a figure which shows an optical access network system provided with MC, PON, an optical fiber termination in a station, and a service demultiplexing apparatus. It is a functional block diagram of the conventional MC communication monitoring apparatus. It is a functional block diagram of the conventional PON communication monitoring apparatus. It is a functional block diagram of the communication monitoring apparatus of one Example by this invention. It is a flowchart which shows the operation | movement at the time of signal type identification of the signal type identification function part in the communication monitoring apparatus of one Example by this invention. It is a figure which shows an example of the MPCP frame count table which concerns on the communication monitoring apparatus of one Example by this invention. It is a figure which shows an example of the PON data frame count table which concerns on the communication monitoring apparatus of one Example by this invention. It is a flowchart which shows operation | movement of the PON communication monitoring function part in the communication monitoring apparatus of one Example by this invention. It is a flowchart which shows operation | movement of the PON link establishment discrimination | determination function part in the communication monitoring apparatus of one Example by this invention. It is a flowchart which shows operation | movement of the PON communication state discrimination | determination function part in the communication monitoring apparatus of one Example by this invention. It is a figure which shows an example of the display screen in case the signal classification of a received signal is PON in the communication monitoring apparatus of one Example by this invention. It is a figure which shows an example of the MC data frame count table to which the priority was allocated in the communication monitoring apparatus of one Example by this invention. It is a flowchart which shows operation | movement of the MC monitoring communication function part in the communication monitoring apparatus of one Example by this invention. It is a flowchart which shows the operation | movement at the time of link state identification of the signal classification identification function part in the communication monitoring apparatus of one Example by this invention. It is a flowchart of the MC communication state discrimination | determination function part in the communication monitoring apparatus of one Example by this invention. It is a figure which shows an example of the display screen in case the signal classification of a received signal is MC in the communication monitoring apparatus of one Example by this invention.

  A communication monitoring apparatus according to an embodiment of the present invention will be described below.

[Device configuration]
FIG. 6 is a functional block diagram of a communication monitoring apparatus according to an embodiment of the present invention. The communication monitoring apparatus 10 of this embodiment includes an optical receiver 101, a signal type identification function unit 102, a PON signal processing function unit 103, an MC signal processing function unit 104, a PON communication monitoring function unit 105, and an MC communication monitoring. A function unit 106 and a display function unit 107 are provided.

  The PON communication monitoring function unit 105 includes an MPCP frame count table 1051 and a PON data frame count table 1053 stored in a memory (not shown), and a PON link establishment determination function unit 1052 for controlling access and update of these tables, respectively. A PON communication state determination function unit 1054.

  The MC communication monitoring function unit 106 includes an MC data frame count table 1061 stored in a memory (not shown) and an MC communication state determination function unit 1062 for controlling access and update of this table.

  In the optical access network system as shown in FIG. 3, the communication monitoring apparatus 10 according to the present embodiment transmits an upstream optical signal from the ONU 2-N to the OLT 3-N via an optical coupler 5-N on an optical fiber transmission line. Whether the communication is based on the MC method or the communication based on the PON method based on the difference in the preamble (such as the presence or absence of LLID) in the MAC frame in the received signal from the received signal received by the optical receiver 101 If the communication is based on the MC system, the link function between the ONU 2-N and the OLT 3-N and the communication status of each priority are displayed on the predetermined display screen by the display function unit 107. The display function unit 107 displays a predetermined display screen indicating the link establishment between the ONU 2-N and the OLT 3-N and the communication status of each priority for each ONU 2-N. Is a device to be displayed.

  Further, the communication monitoring apparatus 10 according to the present embodiment identifies which ONU2-N the data frame is transmitted from the MAC address of the transmission source, and then whether or not the number of data frames is equal to or greater than a predetermined threshold value. It is possible to determine the communication status between each ONU 2-N and each OLT 3-N, and display the determination result on a predetermined display screen.

  Hereinafter, a conventional communication monitoring apparatus will be described in detail.

  The optical receiver 101 receives an upstream optical signal from the ONU 2-N to the OLT 3-N via the optical coupler 5-N on the optical fiber transmission line.

  The signal type identification function unit 102 determines whether the received signal received by the optical receiver 101 is a PON frame, an MC frame, or is not connected, and the difference in the preamble in the MAC frame in the received signal (such as the presence or absence of LLID) It has a function of automatically discriminating based on.

  When the signal type identification function unit 102 determines that the received signal is a PON frame, the PON signal processing function unit 103 processes the received signal as a PON frame, and performs the following frame processing depending on the type of the PON frame.

  As the first frame processing, when the PON frame of the received signal is an MPCP frame, the PON signal processing function unit 103 reads the LLID and the transmission source address from the MPCP frame (which can identify the ONU). The LLID is associated with the transmission source address, and the MPCP frame is counted for each LLID within a certain period of the observation period, and the counted result is stored in the MPCP frame count table 1051 illustrated in FIG. Here, the source address of the upstream MPCP frame corresponds to the MAC address of each ONU 2-N.

  As the second frame processing, when the PON frame of the received signal is a data frame, the PON signal processing function unit 103 reads the user priority bits (priority) of the LLID and VLAN, and the data frame for each LLID and priority. Are stored in the PON data frame count table 1053 illustrated in FIG. 9.

  When the signal type identification function unit 102 determines that the received signal is a PON frame, the PON communication monitoring function unit 105 counts the number of MPCP frames or data frames in the PON frame by the PON signal processing function unit 103. Whether the number of frames or data frames is equal to or greater than a predetermined threshold is compared by the PON communication state determination function unit 1054, and when it is determined that the number is greater than the predetermined threshold, it is determined that communication is in progress. Thus, the PON communication monitoring function unit 105 determines the link establishment between the OLT 3-N and the ONU 2-N for each ONU 2-N, determines the communication state of each service for each ONU 2-N, and determines the determination result. Is created to display a table on a predetermined display screen.

  The PON link establishment determination function unit 1052 determines link establishment for each LLID for the MPCP frame of the PON frame.

  The PON communication status determination function unit 1054 compares the number of MPCP frames or data frames of the PON frame with a predetermined threshold value, and establishes the link establishment status, LLID, and priority between the OLT 3-N and the ONU 2-N. Each time it is determined whether or not communication is in progress, the determination result is sent to the display function unit 107.

  Therefore, the PON communication monitoring function unit 105 determines the MAC address of each ONU 2-N, the state of link establishment between the OLT 3-N and the ONU 2-N, and the priority based on the two processes of the PON signal processing function unit 103. A table (FIG. 13) representing the communication state for each time is created and stored in a memory (not shown). The display function unit 107 can read out the table illustrated in FIG. 13 and display it on a predetermined display screen by an operation of an operator who operates the apparatus or automatically. Here, the reason why the MAC address, not the LLID of the ONU 2-N, is used for display is that the LLID may be changed by the OLT 3-N. Even if a new LLID is assigned to an ONU 2-N, the ONU 2-N can be identified by reading the MAC address from the MPCP frame.

  When the signal type identification function unit 102 determines that the received signal is an MC frame, the MC signal processing function unit 104 processes the received signal as a MAC frame and sets the user priority bit (priority) of the VLAN of the data frame. Data frames are counted for each reading and priority within a certain period of the observation period, and the counted result is stored in the MC data frame count table 1061 illustrated in FIG.

  When the MC type monitoring function unit 106 determines that the received signal is an MC frame by the signal type identification function unit 102, the MC signal processing function unit 104 determines whether the number of data frames in the MC frame is equal to or greater than a predetermined threshold. Is determined by the MC communication state determination function unit 1062 to determine that the communication is in progress when it is determined that the predetermined threshold value is exceeded. Thereby, the MC communication monitoring function unit 106 determines the link establishment between the OLT 3-N and the ONU 2-N for each ONU 2-N, determines the communication status of each service, and displays the determination result on a predetermined display screen. Create a table to display in

  The MC communication state determination function unit 1062 compares the number of data frames of the MC frame with a predetermined threshold, thereby determining the state of link establishment between the OLT 3-N and the ONU 2-N and the priority of the MC frame. It is determined whether or not communication is in progress, and the determination result is sent to the display function unit 107.

  Based on the results of the PON link establishment determination function unit 1052, the PON communication state determination function unit 1054, and the MC communication state determination function unit 1062, the display function unit 107 determines whether the signal type is between OLT3-N and ONU2-N. The link establishment state and the communication state of each priority are displayed on a predetermined display screen. Note that the ONU2-N MAC address is displayed as “MC” because it cannot be known from the data frame flowing through the MC type optical fiber.

  When the transmission of a frame with a certain priority starts immediately after the end time of the predetermined time, the display function unit 107 determines that “waiting” because the number of received frames of the communication monitoring device 10 does not reach the threshold at that time. When the number of received frames reaches a threshold value within a certain period of the next cycle, “Communicating” is displayed.

  Here, in order to describe the priority of the MAC frame in detail, the priority (0 to 7) of the data frame can be determined by the user priority bit (3 bits: 0 to 7) in the VLAN tag of the MAC frame. . At this time, since priority is assigned to one data frame, the priority is not changed within a predetermined time for determining whether or not a link is established.

  Further, to describe the priority bits in detail, in the case of MC, the 3 bits of the user priority field in the VLAN tag of the MAC frame are referred to as user priority bits. It is also called CoS (Class of Service) and is defined in IEEE 802.1p.

  Similar to the PON, in the Gigabit Ethernet (registered trademark) MC, a VLAN tag is added to the MAC frame (data frame) between the OLT and the ONU, and it can be determined from the user priority bit of the VLAN tag. .

  Next, the operation of the communication monitoring apparatus according to an embodiment of the present invention will be further described.

[Device operation]
FIG. 7 is a flowchart showing the operation of the signal type identification function unit 102 when identifying the signal type. The reception signal discrimination performed by the signal type identification function unit 102 will be described below. In the conditional branch 1 (step S1), when the giga idle signal is continuously received within a predetermined time for a predetermined bit (96 bits) or more, it can be determined that it is Gigabit Ethernet (registered trademark), so the conditional branch 2 (step S2). Proceed to In conditional branch 1 (step S1), it is determined that the connection is not established when the specified bits (96 bits) or more are not continuously received. In step S2, if a PON frame is received within the predetermined time, it is determined to be a PON, and otherwise, it is determined to be an MC. Whether or not the received signal is a PON frame can be determined by, for example, a difference in the preamble of the MAC frame between the PON and the MC (such as the presence or absence of LLID).

  The giga idle signal is a gigabit Ethernet (registered trademark) idle signal (no signal). Generally, in Ethernet (registered trademark), it is possible to easily realize bit synchronization on the receiving side by continuously transmitting an idle signal to an inter frame gap (IFG: Inter Flame Gap). Here, IFG is a gap from when a MAC frame is transmitted to when the next MAC frame is transmitted. In Ethernet (registered trademark), there is a rule that a gap of at least 12 bytes (96 bits) is always provided.

  In the PON system and the MC system, the IFG has a giga idle signal, and the communication status is determined using this giga idle signal.

  In addition, although the case where the gear idle signal has received the prescribed bit (96 bits) “more” is described, when the ONU does not transmit the MAC frame in the MC, the giga idle signal is always transmitted. It is. On the other hand, in the PON, the ONU can transmit the MAC frame and the giga idle signal only when the OLT is permitted.

  FIG. 10 is a flowchart showing the operation of the PON monitoring communication function unit 105.

  In step S11, a fixed time (update cycle) that defines the update of the frame count tables (MPCP frame count table 1051 and PON data frame count table 1053) is set.

  In step S12, a link establishment determination threshold is set. The link establishment determination threshold is used to determine the link establishment between the OLT 3-N and the ONU 2-N by comparing with the count number of the MPCP frame.

  In step S13, a communication determining threshold for determining whether or not communication is in progress is set. The communication determining threshold is set for each priority of the data frame. The in-communication determination threshold is used to determine whether or not the communication is in progress by comparing with the count number of the data frame of each priority.

  In step S14, a PON frame is received for a predetermined time.

  In step S15, the PON communication state determination function unit 1054 determines whether or not the number of MPCP frames or data frames in the PON frame counted by the PON signal processing function unit 103 is equal to or greater than a predetermined threshold value. Each time the link establishment between the OLT 3-N and the ONU 2-N is determined, the communication state of each service is determined for each ONU 2-N in step S16, and the MAC of each ONU 2-N is determined in step S17. A table (FIG. 13) is created that represents the address, the state of link establishment between the OLT 3-N and the ONU 2-N, and the communication state for each priority.

  The PON monitoring communication function unit 105 repeats the operations of steps S14 to S17 every predetermined time, thereby enabling display of the determination result every fixed time.

  Here, the link establishment determination threshold will be described in detail. In IEEE 642.3ah, Clause 64, the cycle in which the OLT transmits a GATE frame (downward MPCP frame) to the same ONU is defined as 50 ms at maximum. Further, the cycle in which the ONU transmits a REPORT frame (uplink MPCP frame) to the OLT is defined as 50 ms at maximum. As a result, the communication monitoring apparatus 10 according to an embodiment of the present invention can observe an uplink MPCP frame at a maximum period of 50 ms. That is, if the fixed time of the received signal is 1 s, the link establishment determination threshold is set to 20 frames or less.

  In GE-PON, the ONU transmits an uplink MPCP frame at a maximum period of 1 ms (for example, it can be set to 0.5 m period). Can be set to 1000 frames or less.

  The communication determination threshold can be set for each service (priority). For example, the following cases can be considered depending on the service.

  First, VoIP service: Since voice packets are transmitted in a cycle of 20 ms, the communication threshold for VoIP service is set to 50 frames or less when the signal reception time is 1 s.

  Second, the Internet: Packets are not always sent, but several to several hundred packets are sent when the browser is clicked and the screen is updated. It depends heavily on the user, and based on an empirical rule using a communication monitoring device prototype, assuming that the signal reception time is 1 s, the Internet communication discrimination threshold is set to 10 frames.

  FIG. 11 is a flowchart of the PON link establishment determination function unit 1052. First, the MPCP frame count table 1051 is read (step S21). Next, for each LLID in the read MPCP frame count table 1051, the number of MPCP frames of the received signal is compared with the set link establishment determination threshold (steps S22 and S23), and the link establishment determination threshold with the number of MPCP frames set. If it is above, it is determined that the link between the OLT 3-N and the ONU 2-N is established (step S24). Otherwise, it is determined that the link is not established (step S25). Finally, a determination result for each LLID is sent to the display function unit 107 after a certain time, and the MPCP frame count table 1051 is cleared for the next certain time, and the process ends (steps S26 and S27).

  FIG. 12 is a flowchart of the PON communication state determination function unit 1054. First, the PON data frame count table 1053 is read (step S31). Next, for each LLID and priority in the read PON data frame count table 1053, the number of received data frames is compared with the set communication discrimination threshold (steps S32, S33, S34), and the number of received data frames. Is equal to or greater than the set communication determination threshold value, it is determined that communication is in progress (step S35), and otherwise, it is determined that the communication apparatus is in a standby state (step S36). Finally, a determination result for each LLID and priority is sent to the display function unit 107 after a certain time, and the PON data frame count table 1053 is cleared for the next certain time, and the process ends (steps S37, S38, S39). ).

  FIG. 13 shows an example of a display screen when the signal type of the received signal is communication by the PON method. The display function unit 107, based on the determination results of the PON link establishment determination function unit 1052 and the PON communication state determination function unit 1054 in the PON communication monitoring function unit 105, the signal type, the ONU MAC address, the link state, and each priority. Is displayed on a predetermined display screen. The display screen may be displayed on a display screen included in the communication monitoring device 10 or may be configured to be output to an external computer device for display. Here, in addition to the display function unit 107, it is also possible to add a sound notification function unit (not shown) for notifying the communication status with sound for each priority. By notifying the communication status with sound, when a person engaged in the switching work uses the communication monitoring device 10, the communication status can be recognized without requiring confirmation of the display screen in the communication monitoring device 10. Work efficiency of construction improves.

  FIG. 15 is a flowchart showing the operation of the MC communication monitoring function unit 106.

  In step S41, a fixed time (update cycle) that defines the update of the frame count table (MC data frame count table 1061) is set.

  In step S42, a link establishment determination threshold value is set. The link establishment determination threshold is used to determine the link establishment between the OLT 3-N and the ONU 2-N by comparing with the count number of the MC data frame.

  In step S43, a communication determination threshold for determining whether or not communication is in progress is set. The communication determining threshold is set for each priority of the data frame. The in-communication determination threshold is used to determine whether or not the communication is in progress by comparing with the count number of the data frame of each priority.

  In step S44, the MC data frame is received for a predetermined time.

  In step S45, the MC communication state determination function unit 1062 determines whether or not the number of MC data frames counted by the MC signal processing function unit 104 is equal to or greater than a predetermined threshold value, so that the OLT 3-N is determined for each ONU 2-N. In step S46, the communication status of each service is determined for each ONU 2-N. In step S47, the link between the OLT 3-N and the ONU 2-N is determined. A table (not shown) representing the link establishment state and the communication state for each priority is created.

  FIG. 16 is a flowchart showing the operation of the signal type identification function unit 102 at the time of link state identification. If the giga idle signal is continuously received within a predetermined time for a predetermined bit (96 bits) or more, the link is established (steps S51 and S52). Otherwise, the link is not established (steps S51 and S53).

  FIG. 17 is a flowchart showing the operation of the MC communication state determination function unit 1062. First, the MC data frame count table is read (step S61). Next, for each priority in the read MC data frame count table 1061, the number of MC data frames of the received signal is compared with the set communication discrimination threshold (steps S62 and S63), and the communication with the number of MC data frames set. If it is greater than or equal to the determination threshold, it is determined that communication is in progress (step S64), and if not, it is determined that it is in a standby state (step S65). Finally, the MC data frame count table 1061 is cleared and the process ends (steps S66 and S67). FIG. 18 shows an example of a display screen when the signal type of the received signal is communication based on the MC method.

  As described above, according to the communication monitoring apparatus 10 and the communication monitoring method of this embodiment, it is possible to determine whether or not communication is being performed for each service in the optical access network.

  Furthermore, according to the communication monitoring apparatus 10 and the communication monitoring method of the present embodiment, the link states before and after the switching work can be compared, and it is possible to easily confirm whether or not the correct work has been performed.

  Further, according to the communication monitoring apparatus 10 and the communication monitoring method of the present embodiment, it is possible to avoid interruption during service use (during communication) in the switching work, so that service quality is greatly improved for the user.

  In particular, since the switching construction worker can confirm the service usage status of the user, it is possible to perform flexible work according to the service usage status. Furthermore, there is no need to notify / explain the switching work to the user in advance, and the operation for handling the user can be greatly reduced.

  In this embodiment, since the link establishment and communication state are determined for each MAC address of the ONU 2-N, the present invention can be applied to a multi-LLID that assigns a plurality of LLIDs to the ONU 2-N. It is clear that the present invention can also be applied to a 10 gigabit MC and a 10 gigabit PON.

  Further, the communication monitoring apparatus 10 of the present invention can be configured as a computer, and a program for realizing each function described above is stored in a memory (not shown) provided inside or outside the computer. Such a memory can be realized by an external storage device such as an external hard disk or an internal storage device such as a RAM. The control unit in the communication monitoring apparatus 10 that executes the program can be realized by a central processing unit (CPU) or the like. In other words, each function can be realized on the computer by the CPU appropriately reading a program in which the processing content for realizing each function is described from the memory. Here, any one of the functional units may be realized by a part of hardware.

  The above-described program can be recorded on a computer-readable recording medium. As the computer-readable recording medium, any recording medium such as a magnetic recording device, an optical disk, a magneto-optical recording device, and a semiconductor memory may be used.

  Although specific embodiments have been described in the above-described embodiments, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the invention. For example, in the above-described embodiments, the optical access network system in which the MC method and the PON method are mixed has been described as an example. However, it is needless to say that the present invention can be applied to an optical access network system configured only by an MC method or PON method network. Absent. Therefore, the present invention is not limited to the above-described embodiments, and many modifications can be realized without departing from the gist thereof.

  According to the present invention, link establishment and communication status are determined for each MAC address of ONU2-N, which is useful for traffic monitoring in an optical access network.

1,1-N communication terminal 2,2-N ONU
3,3-N OLT
4,4-N optical splitter 5 optical fiber termination 5-N optical coupler 6 service demultiplexer 7 OTDR (Optical Time-Domain Reflectometer)
8 MC Communication Monitoring Device 9 PON Communication Monitoring Device 10 Communication Monitoring Device 81 Optical Receiver 82 MC Signal Processing Function Unit 83 Display Function Unit 91 Optical Receiver 92 MC Signal Processing Function Unit 93 Display Function Unit 101 Optical Receiver 102 Signal Type Identification Function Unit 103 PON signal processing function unit 104 MC signal processing function unit 105 PON communication monitoring function unit 106 MC communication monitoring function unit 107 Display function unit 1051 MPCP frame count table 1052 PON link establishment determination function unit 1053 PON data frame count table 1054 PON communication state determination Function unit 1061 MC data frame count table 1062 MC communication state determination function unit

Claims (10)

A communication monitoring device for monitoring a communication state of an optical access network system in which one or more optical subscriber termination devices (OLT) and one or more optical network termination devices (ONU) are connected via an optical fiber,
An optical signal receiving means for receiving an upstream optical signal from the ONU to the OLT via an optical coupler on the optical fiber transmission line;
A signal type identifying means for automatically discriminating whether the communication is based on the MC system or the PON system based on the difference in the preamble in the MAC frame in the received signal from the received signal received by the optical signal receiving means; ,
Communication monitoring means for monitoring the communication state in the MC system or the communication state in the PON system according to the signal type determined by the signal type identifying means;
A communication monitoring apparatus comprising:   When the communication monitoring means determines whether the communication is based on the MC system or the communication based on the PON system by the signal type identification means, if the communication is based on the MC system, the link establishment between the ONU and the OLT and The communication monitoring apparatus according to claim 1, wherein data representing a communication state of each priority is generated.   When the communication monitoring means determines whether the communication is based on the MC system or the communication based on the PON system by the signal type identification means, each link between the ONU and the OLT is a communication based on the PON system. The communication monitoring apparatus according to claim 1 or 2, wherein data representing the establishment and the communication state of each priority for each ONU is generated.   The communication monitoring apparatus according to claim 2, further comprising display means for displaying each of the generated data on a predetermined display screen.   The signal type identification means determines that the giga idle signal is continuously received within a predetermined time for a predetermined bit or more, and determines that it is in a connected state, and if it does not continuously receive the predetermined bit or more, determines that it is not connected. The communication monitoring apparatus according to claim 1, wherein the communication monitoring apparatus is characterized. PON signal processing means for performing frame processing on the PON frame of the received signal,
When it is determined by the signal type identification means that the communication is based on the PON method,
The PON signal processing means is
As the frame processing, when the PON frame is an MPCP frame, the LLID and the source address are read from the MPCP frame, the corresponding ONU is identified, the LLID and the source address are associated, and the MPCP frame is set for each LLID for a certain period of time. Has the function to count in,
The communication monitoring unit compares the number of MPCP frames in the PON frame with a predetermined threshold value when the signal type identification unit determines that the communication is based on the PON method, If it is determined that it is greater than or equal to the threshold value, it is determined that communication is in progress, the state of link establishment between the ONUs for each ONU and the ONU, and whether communication is being performed for each LLID and priority, 5. The communication monitoring apparatus according to claim 4, wherein the determined result is sent to the display means. PON signal processing means for performing frame processing on the PON frame of the received signal,
When it is determined by the signal type identification means that the communication is based on the PON method,
The PON signal processing means is
As a frame process, when the PON frame is a data frame, it has a function of reading LLID and VLAN user priority bits (priority) from the data frame and counting the data frame within a predetermined time for each LLID and priority. ,
The communication monitoring unit compares the number of data frames in the PON frame with a predetermined threshold value when the signal type identification unit determines that the communication is based on the PON method, If it is determined that it is greater than or equal to the threshold value, it is determined that communication is in progress, the state of link establishment between the ONUs for each ONU and the ONU, and whether communication is being performed for each LLID and priority, 5. The communication monitoring apparatus according to claim 4, wherein the determined result is sent to the display means. MC signal processing means for performing frame processing on the MC frame of the received signal,
When it is determined by the signal type identification means that the communication is based on the MC method,
The MC signal processing means includes:
As frame processing, it has the function of reading the user priority bit (priority) of the VLAN from the data frame of the MC frame, and counting the data frame within a certain time for each priority,
The communication monitoring unit compares whether the number of data frames in the MC frame is equal to or greater than a predetermined threshold when the signal type identification unit determines that the communication is based on the MC method, When it is determined that the threshold is greater than or equal to the threshold, it is determined that communication is being performed, the state of link establishment between the OLT and the ONU is determined, whether communication is being performed for each priority, and the determination result is The communication monitoring apparatus according to claim 4, wherein the communication monitoring apparatus is sent to the display unit. A communication monitoring method for monitoring a communication state of an optical access network system in which one or more optical subscriber termination devices (OLT) and one or more optical network termination devices (ONU) are connected via an optical fiber,
Receiving an upstream optical signal from the ONU to the OLT via an optical coupler on an optical fiber transmission line;
Automatically determining from the received signal received in the step whether the communication is based on MC or PON based on the preamble difference in the MAC frame in the received signal;
Monitoring the communication state in the MC method or the communication state in the PON method according to the signal type determined in the step;
The communication monitoring method characterized by including. A computer configured as a communication monitoring device for monitoring a communication state of an optical access network system in which one or more optical subscriber termination devices (OLT) and one or more optical network termination devices (ONU) are connected via an optical fiber In addition,
Receiving an upstream optical signal from the ONU to the OLT via an optical coupler on an optical fiber transmission line;
Automatically determining from the received signal received in the step whether the communication is based on MC or PON based on the preamble difference in the MAC frame in the received signal;
Monitoring the communication state in the MC method or the communication state in the PON method according to the signal type determined in the step;
A program for running

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