JP2014135679A - Terminal-side communication device, station-side device and communication failure restoration method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To receive a forcible stop signal even when a failure occurs in a part for processing wavelength used in a signal from an OLT (Optical Line Terminal) to each ONU (Optical Network Unit).SOLUTION: An ONU of the present invention is compatible with two different PON systems and is operated in selected one PON system. The ONU includes a first termination circuit for processing a reception signal compatible with the PON system currently in operation; a second termination circuit for processing a reception signal compatible with the PON system not in operation; and a control part for stopping outputting of a transmission signal compatible with the PON system currently in operation, when a reception signal, transmitted from a station-side device in the PON system currently in operation and processed in the second termination circuit, is a forcible stop signal indicating the stop of the transmission signal.

Description

  The present invention relates to an optical access system, particularly a PON (Passive Optical Network), which connects one station side communication device (OLT: Optical Line Terminal) and a plurality of terminal side communication devices (ONU: Optical Network Unit) via an optical fiber. It is about the system.

The PON system connects one station side communication device (hereinafter referred to as OLT) and a plurality of terminal side communication devices (hereinafter referred to as ONU) using passive optical branching devices such as optical fibers and optical splitters. In the PON system, an ONU is connected to a branch line optical fiber installed in a user's house or outdoors, thereby enabling communication with an OLT installed in a station building.

The PON system includes, for example, EPON (Ethernet (registered trademark) PON) having an Ethernet frame for communication between OLT and ONU having a transmission rate of 100 Mbps and GE-PON (Gigabit Ethernet (registered trademark)) having a transmission rate of 1 Gbps. PON) and 10G-EPON having a transmission rate of 10 Gbps.

  The wavelength used in the signal from the OLT of each PON system to each ONU is 1540 to 1570 nm in the EPON system, 1480 to 1500 nm in the GE-PON system, and 1574 to 1580 nm in the 10G-EPON system.

  The PON system is switched to increase the transmission speed. For example, switching from the EPON system to the GE-PON system. In switching the PON system, the network topology is the same, and transmission lines with the same specifications can be used. However, the OLT and ONU corresponding to different PON systems cannot be connected for the following reasons. The first reason is that the wavelength band of the downstream signal is different as described above. The second reason is that the communication protocol is different. Data is not conducted between the OLT and ONU corresponding to different PON systems.

For the above reasons, for example, when switching the system from EPON to GE-PON, if the EPON ONUs on the user's home side are sequentially replaced with GE-PON ONUs, the EPON on the station side will eventually be Until the OLT is replaced with the GE-PON OLT, communication cannot be performed at the user's home exchanged with the GE-PON ONU.

Therefore, when system switching is performed, it is necessary to exchange all EPON ONUs on the user's home side simultaneously with GE-PON ONUs, and simultaneously exchange the EPON OLT on the station side with GE-PON OLT. However, this method is inefficient in migration work.

  As one of the efficient migration methods, there is introduction of an integrated ONU corresponding to two different PON systems. For example, there are EPON / GE-PON integrated ONU and GE-PON / 10G-EPON integrated ONU corresponding to different PON systems.

  In the PON system, since an optical transmission path between the OLT and the optical coupler is shared by a plurality of ONUs, TDI (Time Division Multiple Access) is used from each ONU to the OLT. In TDMA, the OLT instructs each ONU in advance the transmission timing of a signal from the ONU to the OLT (hereinafter referred to as an upstream signal), and each ONU transmits an optical signal in bursts at the instructed transmission timing. The transmission of the optical signal is stopped except for the instructed transmission timing.

  When a failure occurs in an ONU, there may be a case where an ONU that has failed at the transmission timing of another ONU transmits an optical signal. In that case, a communication failure occurs in which part or all of the non-failing ONUs connected to the OLT cannot be communicated.

  The PON system has a communication failure recovery method for recovering a communication failure of another ONU when an ONU that has failed at the transmission timing of the other ONU transmits an optical signal. In Patent Document 1, a forced stop signal is sent to an ONU at a wavelength used for a signal from the OLT of the PON system to each ONU, and communication failures of other ONUs are restored.

JP-A-11-154958

  As described above, in the conventional PON system, the forced stop signal is transmitted using the wavelength used in the signal from the OLT of the PON system to each ONU. Therefore, when the part which processes the wavelength used by the signal from the OLT to each ONU in the ONU fails, the forced stop signal cannot be received and the communication failure of other ONUs cannot be recovered. There is.

The present invention has been made in order to solve the above-described problems, and even if a portion of the ONU that processes the wavelength used in the signal from the OLT to each ONU has failed, the forced from the OLT The purpose is to enable reception of a stop signal.

  The present invention has been made to solve the above-described problems. According to the present invention, the ONU corresponds to two different PON systems, and is operated by any one selected PON system. The first termination circuit that processes the received signal corresponding to the PON system of the second, the second termination circuit that processes the received signal corresponding to the non-operating PON system, and the transmission from the station side device in the operating PON system And a control unit that stops output of the transmission signal corresponding to the PON system in operation when the reception signal processed by the second termination circuit is a forced stop signal instructing to stop the transmission signal. .

  As described above, according to the present invention, the ONU can receive the forcible stop signal from the OLT side even when a part of the ONU that processes the wavelength used in the signal from the OLT to each ONU fails. As a result, even when the wavelength processing unit used in the signal from the OLT to each ONU in the ONU fails, the ONU can stop the transmission of the upstream signal according to the forced stop signal from the OLT side. As a result, it becomes possible to recover communication failures of other ONUs accommodated in the OLT.

1 is a configuration diagram of a PON system in Embodiment 1. FIG. It is a figure which shows the frame format of the forced stop signal of wavelength 1540-1570nm. It is a figure which shows the frame format of the forced stop signal of wavelength 1480-1500nm. FIG. 10 is a diagram illustrating an operation flow of the OLT and the forced stop signal transmitter when the ONU fails in the first embodiment. It is a figure which shows the operation | movement flow of OLT and a forced stop signal transmitter when ONU fails in Embodiment 2. FIG.

Embodiment 1 FIG.
FIG. 1 is a configuration diagram of a PON system according to Embodiment 1 of the present invention. The PON system includes a station-side device 100, a plurality of ONUs 103a and 103b (collectively referred to as ONUs), an optical splitter (optical splitter) 104, a trunk optical fiber 105, an optical coupler 106, and a plurality of branch optical fibers 107a. 107b (collectively referred to as a branch optical fiber). Although FIG. 1 discloses the case where there are two ONUs, the number is not limited to this. The station side device 100 includes an OLT 101 and a forced stop signal transmitter 102.

The OLT 101 and the ONU are an upstream signal (hereinafter referred to as an OLT signal) from the ONU to the OLT using the wavelength used in the PON system in operation via the optical splitter 104, the trunk optical fiber 105, the optical coupler 106, and the branch optical fiber. (Uplink main signal) and a downlink signal (hereinafter referred to as a downlink main signal) which is a signal from the OLT to the ONU. When the operating PON system is an EPON system, the wavelength of the downstream main signal used in the operating PON system is 1540 to 1570 nm. When the operating PON system is a GE-PON system, the wavelength is used in the operating PON system. The wavelength of the downlink main signal is 1480 to 1500 nm. When the operating PON system is a 10G-EPON system, the wavelength of the downlink main signal used in the operating PON system is 1574 to 1580 nm.

The OLT 101 includes an ONU failure detection unit 123, an ONU confirmation unit 124, and a wavelength determination unit 125.

The ONU failure detection unit 123 detects a terminal-side communication device that transmits at a timing different from the allocated transmission timing (hereinafter, illegal transmission).

The ONU confirmation unit 124 identifies the terminal-side communication device detected by the ONU failure detection unit 123. Specific information includes the MAC address of the ONU. Also, it is confirmed whether the detected terminal side communication device is a terminal side communication device corresponding to two different PON systems. Information indicating whether the connected ONU is a terminal-side communication device corresponding to two different PON systems is held by the OLT 101 or the operator.

The wavelength determination unit 125 supports a non-operating PON system when it is confirmed that the terminal-side communication device that performs unauthorized transmission by the ONU confirmation unit is a terminal-side communication device that supports two different PON systems. The wavelength to be determined is determined as the wavelength of the forced stop signal. The PON system used for transmitting the forced stop signal may be determined as a non-operating PON system. The OLT 101 or the operator holds information on the wavelength corresponding to the termination circuit mounted on the connected ONU. For example, the PON system in operation is an EPON system, and a termination circuit mounted on a connected ONU is an EPON termination circuit 111 corresponding to a wavelength of 1540 to 1570 nm, and a GE-PON termination circuit 109 corresponding to a wavelength of 1480 to 1500 nm. In this case, the wavelength used for the forced stop signal is 1480 to 1500 nm of the GE-PON system which is a non-operating PON system. In addition, the PON system in operation is a GE-PON system, and the termination circuit mounted on the connected ONU is an EPON termination circuit 111 corresponding to a wavelength of 1540 to 1570 nm, and a GE-PON termination corresponding to a wavelength of 1480 to 1500 nm. In the case of the circuit 109, the wavelength used for the forced stop signal is the EPON system 1540 to 1570 nm which is a non-operating PON system.

When the OLT 101 or the operator detects a failure of the connection ONU, the OLT 101 notifies the forced stop signal transmitter 102 of a forced stop signal transmission instruction. In addition, when a faulty ONU is specified, specific information such as a MAC address of the ONU is notified to the forced stop signal transmitter 102. If the wavelength used for the forced stop signal or the PON system is determined, the information is notified to the forced stop signal transmitter 102.

The forced stop signal transmitter 102 that has received an instruction to transmit a forced stop signal transmits a forced stop signal to the ONU via the optical splitter 104, the trunk optical fiber 105, the optical coupler 106, and the branch optical fiber. The forcible stop signal uses a wavelength different from the wavelength used for the downlink main signal. The optical branching device 104 multiplexes the forced stop signal from the forced stop signal transmitter 102 and the downlink main signal from the OLT 101.

The frame format of the forced stop signal conforms to the system corresponding to the wavelength used for the forced stop signal. This eliminates the need for the ONU that receives the forced stop signal to provide a new termination circuit.

FIG. 2 is a diagram illustrating a frame format of a forced stop signal having a wavelength of 1540 to 1570 nm. The frame format conforms to the frame format of the EPON system corresponding to wavelengths 1540 to 1570 nm. Specifically, a preamble part, a PON header part, an SFD part for notifying the start of an Ethernet (registered trademark) frame, a DA part as a destination address, an SA part as an oscillation source address, and a TYPE for identifying an upper layer protocol Part, IP header part, payload, and FCS part used for error detection. The forced stop signal is mapped to the control signal area A of the PON header portion of the frame.

FIG. 3 is a diagram showing a frame format of a forced stop signal having a wavelength of 1480 to 1500 nm. The frame format conforms to the frame format of the GE-PON system corresponding to the wavelength of 1480 to 1500 nm. Specifically, it includes a preamble part, a DA part as a destination address, an SA part as an oscillation source address, a TYPE part for identifying a frame length and an upper layer protocol, a payload, and an FCS part used for error detection. At this time, the forced stop signal is mapped to the control signal area B of the preamble portion of the frame.

Further, the forced stop signal transmitter 102 may be configured in the OLT 101. The forced stop signal transmitter 102 can be said to be a forced stop signal transmitter of the station side device 100.

It may also be configured in the video OLT. For example, when the wavelength used in the signal from the video OLT to each ONU is 1540 to 1570 nm, it is the same as the wavelength used in the downlink main signal of the EPON system. Therefore, it is useful to configure the forced stop signal transmitter 102 that transmits a forced stop signal having a wavelength of 1540 to 1570 nm in the video OLT.

The ONU 103a includes two termination circuits corresponding to different wavelengths, an EPON termination circuit 108, a GE-PON termination circuit 109, an optical splitter 110, and an O / E (Optical / Electrical Converter) circuit 111 that converts an optical signal into an electrical signal. , O / E circuit 112, optical multiplexer / demultiplexer 113, determination circuit 114, first selection circuit 115, second selection circuit 116, user side port 117, MUX 118, E / O for converting electrical signals into optical signals ( An electric / optical converter circuit 119, a power supply control unit 120, a switch 121, and a power supply unit 122 are included.

In FIG. 1, the case of the EPON / GE-PON integrated ONU including the EPON termination circuit 111 and the GE-PON termination circuit 109 as two termination circuits corresponding to different wavelengths is disclosed, but the present invention is not limited to this. . For example, there is a GE-PON / 10G-EPON integrated ONU including a GE-PON termination circuit and a 10G-PON termination circuit as two termination circuits corresponding to different wavelengths.

The optical branching unit 110 receives the downstream signal from the branch optical fiber, branches the signal according to the wavelength corresponding to the termination circuit, and outputs the branched signal to the O / E circuit 111 or the O / E circuit 112. In the EPON / GE-PON integrated ONU of FIG. 1, when the wavelength of the received signal is 1540 to 1570 nm, it is output to the O / E circuit 111, and when the wavelength of the received signal is 1480 to 1500 nm, The signal is output to the O / E circuit 112 via the wave filter 113.

The O / E circuit 111 is a circuit corresponding to a wavelength of 1540 to 1570 nm, and outputs the converted electric signal to the EPON termination circuit 108. The O / E circuit 112 is a circuit corresponding to a wavelength of 1480 to 1500 nm, and outputs the converted electric signal to the GE-PON termination circuit 109.

The EPON termination circuit 108 is a termination circuit that operates according to the communication protocol of the EPON system, and terminates the received signal having a wavelength of 1540 to 1570 nm to perform various signal processing. That is, when the ONU 103a is connected to the EPON system, the EPON termination circuit 108 terminates the downlink main signal. When the ONU 103a is connected to the GE-PON system, the EPON termination circuit 108 terminates the forced stop signal and performs signal processing. The signal processed by the EPON termination circuit 108 is output to the determination circuit 114, the first selection circuit 115, and the second selection circuit 116. Alternatively, a reception main signal reception presence / absence signal may be output to the determination circuit 114. The upstream signal input from the first selection circuit 115 is generated according to the communication protocol of the EPON system, and is output to the MUX 118.

The GE-PON termination circuit 109 is a termination circuit that operates in accordance with the communication protocol of the GE-PON system, and terminates a received signal having a wavelength of 1480 to 1500 nm to perform various signal processing. That is, when the ONU 103a is connected to the GE-PON system, the GE-PON termination circuit 109 terminates the downlink main signal. When the ONU 103a is connected to the EPON system, the GE-PON termination circuit 109 terminates the forced stop signal and performs signal processing. The signal processed by the GE-PON termination circuit 109 is output to the determination circuit 114, the first selection circuit 115, and the second selection circuit 116. Alternatively, a reception main signal reception presence / absence signal may be output to the determination circuit 114. Further, the upstream signal input from the first selection circuit 115 is generated according to the communication protocol of the GE-PON system, and is output to the MUX 118.

Based on the signals received from the EPON termination circuit 108 and the GE-PON termination circuit 109, the determination circuit 114 determines from which termination circuit the main downlink signal has been output. The determination result is output to the first selection circuit 115, the second selection circuit 116, and the MUX 118. When the determination circuit 114 determines that the downstream main signal is output from the EPON termination circuit 108, it can determine that the own ONU is connected to the EPON system. Similarly, when it is determined that the downstream main signal is output from the GE-PON termination circuit 109, it is possible to determine that the own ONU is connected to the GE-PON system.

The first selection circuit 115 selects the signal output from the termination circuit from which the downlink main signal is output based on the determination result by the determination circuit 114, and outputs the signal to the outside, for example, the user terminal via the user side port 117. . Further, an uplink signal input from the outside, for example, a user terminal via the user side port 117 is output to a termination circuit from which the downlink main signal is output based on a determination result by the determination circuit 114.

Based on the determination result by the determination circuit 114, the MUX 118 outputs the uplink signal input from the termination circuit from which the downlink main signal is output to the E / O circuit 119.

The E / O circuit 119 is a conversion circuit corresponding to 1310 nm that is the wavelength of the upstream signal used in EPON and GE-PON, converts the upstream signal from the MUX 118 into an optical signal, and passes through the optical branching unit 110. Output to branch optical fiber.

Based on the determination result by the determination circuit 114, the second selection circuit 116 is a termination circuit (a termination circuit that processes a received signal corresponding to the PON system in operation) from which the downlink main signal is output ( A signal output from a termination circuit that processes a received signal corresponding to a non-operating PON system is selected and output to a control unit capable of controlling the output of uplink signal transmission. A specific example of the control unit is the power supply control unit 120. That is, a forced stop signal is output to the power supply control unit 120.

When receiving the forced stop signal from the second selection circuit, the power control unit 120 turns off the switch 121 and stops the power supply from the power supply unit 122 to the part related to the uplink signal transmission. As a result, power supply to the portion related to uplink signal transmission is cut off, transmission of the uplink signal from the failed ONU 103a is stopped, unauthorized transmission can be stopped, and communication failures of other ONUs are restored. The part related to uplink signal transmission includes the MUX 118, the E / O circuit 119, and the like.

Next, the operation will be described. FIG. 4 is a diagram showing an operation flow of the OLT and the forced stop signal transmitter when the ONU fails in the first embodiment of the present invention.

In step S401, the ONU failure detection unit 123 of the OLT 101 or the operator executes failure detection processing for the connected ONU. Detect unauthorized transmissions. If a failure is detected, the process proceeds to step S402. If no failure is detected, the failure detection process in step S401 is repeated.

In step S402, the ONU confirmation unit 124 or the operator of the OLT 101 executes a failure ONU specifying process. When the failure ONU can be identified, the process proceeds to step S403. If the failure ONU cannot be identified, the process is terminated. Alternatively, as in the conventional PON system, the forced stop signal is transmitted using the wavelength used in the downstream signal of the PON system in operation. Alternatively, the process proceeds to step S404.

In step S403, the ONU confirmation unit 124 or the operator of the OLT 101 executes a confirmation process for the presence / absence of a termination circuit other than a system that is in operation (corresponding to a system that is not in operation) for the faulty ONU. When there is a termination circuit other than the one corresponding to the system in operation, the wavelength determination unit 125 of the OLT 101 confirms the wavelength / system corresponding to the termination circuit, and executes the determination process of the wavelength used in the forced stop signal. Thereafter, the process proceeds to step S404. If there is no termination circuit other than the one corresponding to the operating system, the process is terminated. Alternatively, as in the conventional PON system, the forced stop signal is transmitted using the wavelength used in the signal from the OLT of the PON system to each ONU.

For example, when the failure ONU is an EPON / GE-PON integrated ONU and the PON system in operation is an EPON system, the termination corresponding to the GE-PON system, which is a termination circuit other than the one corresponding to the EPON system being operated as the failure ONU A circuit exists. It decides to use the wavelength corresponding to the GE-PON system, which is a non-operating PON system, for the forced stop signal, and proceeds to step S404.

For example, if the failure ONU is an EPON / GE-PON integrated ONU and the PON system in operation is a GE-PON system, it is compatible with an EPON system that is a termination circuit other than the GE-PON system currently in operation as a failure ONU There is a termination circuit. It is determined that the wavelength corresponding to the EPON system which is a non-operating PON system is used for the forced stop signal, and the process proceeds to step S404.

In step S404, the OLT 101 or the operator notifies the forced stop signal transmitter 102 of a forced stop signal transmission instruction. If a faulty ONU has been identified in step S402, the OLT 101 or the operator notifies the forced stop signal transmitter 102 of the ONU's MAC address and the like. If the wavelength / system used in the forced stop signal is determined in step S403, the OLT 101 or the operator notifies the forced stop signal transmitter 102 of the information.

In step S405, the forcible stop signal transmitter 102 transmits a forcible stop signal at a wavelength other than that for the system in operation. In step S404, if the ONU MAC address or the like is received, the forced stop signal transmitter 102 transmits a forced stop signal to the ONU. If the wavelength / system used in the forced stop signal is received in step S404, the forced stop signal transmitter 102 transmits the forced stop signal at the wavelength.

Step S402 and step S403 may be omitted. If omitted, in step S405, the forced stop signal transmitter 102 transmits a forced stop signal at a predetermined wavelength to all connected ONUs.

As described above, even when the termination circuit of the downstream main signal of the ONU fails, the ONU can receive the forced stop signal from the OLT side. Thereby, even when the termination circuit of the downstream main signal of the ONU fails, the ONU can stop the transmission of the upstream signal according to the forced stop signal from the OLT side. As a result, it becomes possible to recover communication failures of other ONUs accommodated in the OLT.

In addition, in an integrated ONU that supports two different PON systems introduced to improve the efficiency of migration work at the time of system switching, only the termination circuit corresponding to the system before switching is used before switching the system. There is no use of termination circuitry for later systems. Further, after the system is switched, only the termination circuit corresponding to the system after the switching is used, and the termination circuit corresponding to the system before the switching is not used. Therefore, if attention is paid only before the switching work is started and after the switching work is completed, useless hardware is installed. However, in the present invention, the forced stop signal is signal-processed using a termination circuit corresponding to a non-operating system. Therefore, it is possible to obtain an effect of effectively utilizing hardware corresponding to other than the PON system in operation of the integrated ONU corresponding to two different PON systems.

Embodiment 2. FIG.
The configuration diagram of the PON system in the second embodiment of the present invention is the same as that in the first embodiment. A description of portions having the same functions as those in Embodiment 1 is omitted.
The forced stop signal transmitter 102 according to the second embodiment of the present invention is obtained by adding a function of transmitting a power recovery signal to the forced stop signal transmitter 102 according to the first embodiment. The other configuration is the same as that of the PON system of the first embodiment.

The forced stop signal transmitter 102 that has transmitted the forced stop signal transmits a power recovery signal to the ONU via the optical splitter 104, the trunk optical fiber 105, the optical coupler 106, and the branch optical fiber after transmitting the forced stop signal. . The power recovery signal uses a wavelength different from the wavelength used for the downlink main signal. The optical branching device 104 multiplexes the power recovery signal from the forced stop signal transmitter 102 and the downlink main signal from the OLT 101.

The wavelength used in the power supply recovery signal is a wavelength that corresponds to the termination circuit mounted on the connected ONU. The OLT 101 or the operator holds information on the wavelength corresponding to the termination circuit mounted on the connected ONU.

The frame format of the power recovery signal conforms to the system corresponding to the wavelength used for the power recovery signal. This eliminates the need for the ONU that receives the power recovery signal to provide a new termination circuit.

FIG. 2 is a diagram illustrating a frame format of a power recovery signal having a wavelength of 1540 to 1570 nm. The frame format conforms to the frame format of the EPON system corresponding to wavelengths 1540 to 1570 nm. Specifically, a preamble part, a PON header part, an SFD part for notifying the start of an Ethernet (registered trademark) frame, a DA part as a destination address, an SA part as an oscillation source address, and a TYPE for identifying an upper layer protocol Part, IP header part, payload, and FCS part used for error detection. The power recovery signal is mapped to the control signal area A of the PON header portion of the frame. The power recovery signal is a value different from the forced stop signal.

FIG. 3 is a diagram illustrating a frame format of a power recovery signal having a wavelength of 1480 to 1500 nm. The frame format conforms to the frame format of the GE-PON system corresponding to the wavelength of 1480 to 1500 nm. Specifically, it includes a preamble part, a DA part as a destination address, an SA part as an oscillation source address, a TYPE part for identifying a frame length and an upper layer protocol, a payload, and an FCS part used for error detection. At this time, the power recovery signal is mapped to the control signal area B of the preamble portion of the frame. The power recovery signal is a value different from the forced stop signal.

The EPON termination circuit 108 is a termination circuit that operates according to the communication protocol of the EPON system, and terminates the received signal having a wavelength of 1540 to 1570 nm to perform various signal processing. That is, when the ONU 103a is connected to the EPON system, the EPON termination circuit 108 terminates the downlink main signal. When the ONU 103a is connected to the GE-PON system, the EPON termination circuit 108 terminates the forced stop signal and the power recovery signal and performs signal processing. The signal processed by the EPON termination circuit 108 is output to the determination circuit 114, the first selection circuit 115, and the second selection circuit 116. Alternatively, a reception main signal reception presence / absence signal may be output to the determination circuit 114. Further, the upstream signal input from the first selection circuit is generated according to the communication protocol of the EPON system, and is output to the MUX 118.

The GE-PON termination circuit 109 is a termination circuit that operates in accordance with the communication protocol of the GE-PON system, and terminates a received signal having a wavelength of 1480 to 1500 nm to perform various signal processing. That is, when the ONU 103a is connected to the GE-PON system, the GE-PON termination circuit 109 terminates the downlink main signal. When the ONU 103a is connected to the EPON system, the GE-PON termination circuit 109 terminates the forced stop signal and the power recovery signal and performs signal processing. The signal processed by the GE-PON termination circuit 109 is output to the determination circuit 114, the first selection circuit 115, and the second selection circuit 116. Alternatively, a reception main signal reception presence / absence signal may be output to the determination circuit 114. Further, the upstream signal input from the first selection circuit is generated according to the communication protocol of the GE-PON system, and is output to the MUX 118.

Based on the determination result by the determination circuit 114, the second selection circuit 116 is a termination circuit (a termination circuit that processes a received signal corresponding to the PON system in operation) from which the downlink main signal is output ( A signal output from a termination circuit that processes a received signal corresponding to a non-operating PON system is selected and output to a control unit capable of controlling the output of uplink signal transmission. A specific example of the control unit is the power supply control unit 120. That is, a forced stop signal and a power recovery signal are output to the power control unit 120.

When receiving the forced stop signal from the second selection circuit, the power control unit 120 turns off the switch 121 and stops the power supply from the power supply unit 122 to the part related to the uplink signal transmission. As a result, the power supply to the portion related to uplink signal transmission is cut off, the transmission of the uplink signal from the failed ONU 103a is stopped, and the communication failure of another ONU caused by unauthorized transmission is restored. The part related to uplink signal transmission includes the MUX 118, the E / O circuit 119, and the like.

Further, when the power control unit 120 receives the power recovery signal from the second selection circuit, the power control unit 120 turns on the switch 121 and resumes the power supply from the power unit 122 to the part related to the uplink signal transmission. As a result, power supply to the portion related to uplink signal transmission is resumed, and transmission of the uplink signal from the ONU 103a is resumed.

Next, the operation will be described. FIG. 5 is a diagram showing an operation flow of the OLT and the forced stop signal transmitter when the ONU fails in the second embodiment of the present invention. Since the same reference numerals as those in FIG. 4 are the same as those in the first embodiment, the description thereof is omitted.

In step S405, the forcible stop signal transmitter 102 transmits a forcible stop signal at a wavelength other than that for the system in operation. In step S404, if the ONU MAC address or the like is received, the forced stop signal transmitter 102 transmits a forced stop signal to the ONU. If the wavelength / system used in the forced stop signal is received in step S404, the forced stop signal transmitter 102 transmits the forced stop signal at the wavelength.

In step S406, the forced stop signal transmitter 102 transmits a power recovery signal at a wavelength other than that for the system in operation after the forced stop signal is transmitted. In step S404, if the ONU MAC address or the like is received, the forced stop signal transmitter 102 transmits a power recovery signal to the ONU. If the wavelength / system used in the forced stop signal is received in step S404, the forced stop signal transmitter 102 transmits a power recovery signal at the wavelength. After the process of step S406, the process returns to step S401.

Accordingly, transmission of the upstream signal of the ONU 103a can be resumed without the operation of the user of the ONU 103a, such as when the failure of the ONU 103a is a temporary failure that is recovered by reset (power off). Even when the failure of the ONU 103a is not temporary, a forced stop signal is transmitted again from the forced stop signal transmitter 102, so that communication failures of other ONUs do not occur. The part related to uplink signal transmission includes the MUX 118, the E / O circuit 119, and the like.

Next, when a failure ONU cannot be identified in step S402, the process proceeds to step S404, and a forced stop signal is transmitted, or steps S402 and S403 are omitted and a forced stop signal is transmitted in step S404. An example of the operation will be described with reference to FIG.
In step S404, a forced stop signal is transmitted to all ONUs connected in step S404 at a predetermined wavelength. A forced stop signal is sequentially transmitted to the connected ONUs. The forced stop signal is transmitted, and the ONU failure detection unit 123 checks whether or not the unauthorized transmission is stopped.
When the ONU failure detection unit 123 does not confirm the stop of unauthorized transmission, the forced stop signal transmitter 102 transmits a forced stop signal to the next ONU. The transmission of the forced stop signal to the next ONU may be performed by a timer or an instruction for transmitting the forced stop signal may be given sequentially.
When the ONU failure detection unit 123 confirms the stop of unauthorized transmission, the ONU that has transmitted a forced stop signal immediately before is identified as a failure ONU.
In step S406, the forcible stop signal transmitter 102 transmits a power recovery signal to a wavelength other than that corresponding to the operating system, to the ONUs other than the faulty ONU among the ONUs that transmitted the forcible stop signal in step S405. Specific information of the ONU that has transmitted the forced stop signal and specific information of the faulty ONU include the MAC address of the ONU.

As a result, the power supply of the ONU excluding the faulty ONU is restored without user operation.

As described above, according to the second embodiment, the following effects can be obtained in addition to the effects of the first embodiment. In the case where the ONU failure is a temporary failure that is recovered by reset (power off), transmission of the ONU upstream signal can be resumed without the operation of the ONU user.

100 Station side device 102 Forced stop signal transmitter 103a, 103b ONU
108 EPON Termination Circuit 109 GE-PON Termination Circuit 120 Power Supply Control Unit 123 ONU Failure Detection Unit 124 ONU Confirmation Unit 125 Wavelength Determination Unit

Claims (10)

In a terminal-side communication device that supports two different PON systems and operates in one of the selected PON systems,
A first termination circuit for processing a received signal corresponding to the PON system in operation;
A second termination circuit for processing a received signal corresponding to a non-operating PON system;
Transmission corresponding to the PON system in operation when the reception signal transmitted from the station side device in the PON system in operation and processed by the second termination circuit is a forced stop signal instructing the stop of the transmission signal A terminal-side communication apparatus comprising: a control unit that stops signal output. The control unit is in operation when the received signal transmitted from the station side device in the PON system in operation and processed by the second termination circuit is a power recovery signal instructing to resume output of the transmission signal. The terminal-side communication device according to claim 1, wherein output of a transmission signal corresponding to the PON system is resumed. In a communication failure recovery method for a PON system that corresponds to two different PON systems and has a terminal-side communication device operated by any one selected PON system,
A failure detection step of detecting a terminal-side communication device operating in the PON system and performing unauthorized transmission;
A forced stop signal transmission step of transmitting a forced stop signal that instructs the terminal side communication device detected in the failure detection step to stop the transmission signal using a signal corresponding to a non-operating PON system;
A communication failure recovery method comprising: a transmission stop step in which the terminal-side communication device that has received the forcible stop signal stops output of a transmission signal corresponding to an operating PON system. A confirmation step for confirming whether the terminal side communication device detected in the failure detection step is a terminal side communication device corresponding to two different PON systems;
In the confirmation step, when the terminal side device is a terminal side communication device compatible with two different PON systems, a determination step of determining a wavelength corresponding to a non-operating PON system as a wavelength of the forcible stop signal And
The communication failure recovery method according to claim 3, wherein the forcible stop signal transmission step transmits the forcible stop signal to the terminal-side communication device using the wavelength signal obtained in the determination step. After transmitting the forced stop signal to the terminal-side communication device in the forced stop signal transmission step, the terminal-side communication device is caused to resume output of a transmission signal using a signal corresponding to a non-operating PON system. A power recovery signal transmission step for transmitting a power recovery signal;
The communication failure recovery method according to claim 3, further comprising: a transmission recovery step in which the terminal-side communication device that has received the power recovery signal restarts output of a transmission signal corresponding to an operating PON system. . After transmitting the forced stop signal to the terminal-side communication device in the forced stop signal transmission step, the terminal-side communication device is caused to resume output of a transmission signal using a signal corresponding to a non-operating PON system. A power recovery signal transmission step for transmitting a power recovery signal;
The terminal-side communication device that has received the power recovery signal comprises a transmission recovery step for resuming output of a transmission signal corresponding to an operating PON system,
In the determining step, when the terminal side device is a terminal side communication device corresponding to two different PON systems in the confirmation step, the wavelength corresponding to the non-operating PON system is set to the wavelength of the power recovery signal. And
5. The communication failure recovery method according to claim 4, wherein the power recovery signal transmission step transmits a power recovery signal to the terminal side communication device using the wavelength signal obtained in the determination step. In a station-side device of a PON system that corresponds to two different PON systems and has a terminal-side communication device operated in any one selected PON system,
An ONU failure detection unit that detects a terminal-side communication device that is operating in the PON system and performs unauthorized transmission;
A forced stop signal transmitting unit that transmits a forced stop signal that instructs the terminal side communication device detected by the failure detection unit to stop the transmission signal using a signal corresponding to a non-operating PON system;
A station side device comprising: An ONU confirmation unit for confirming whether or not the terminal-side communication device detected by the ONU failure detection unit is a terminal-side communication device compatible with two different PON systems;
The wavelength at which the wavelength corresponding to the non-operating PON system is determined as the wavelength of the forced stop signal when the terminal side device is a terminal side communication device compatible with two different PON systems in the ONU confirmation unit A determination unit,
The station side apparatus according to claim 7, wherein the forcible stop signal transmission unit transmits the forcible stop signal to the terminal side communication apparatus using the wavelength signal obtained by the wavelength determination unit. The forced stop signal transmitter transmits the forced stop signal to the terminal-side communication device, and then causes the terminal-side communication device to resume output of a transmission signal using a signal corresponding to a non-operating PON system. The station side apparatus according to claim 7, wherein a power supply recovery signal is transmitted. The forced stop signal transmitter transmits the forced stop signal to the terminal-side communication device, and then causes the terminal-side communication device to resume output of a transmission signal using a signal corresponding to a non-operating PON system. Send power recovery signal,
The wavelength determination unit, when the terminal-side device is a terminal-side communication device corresponding to two different PON systems in the ONU confirmation unit, sets a wavelength corresponding to a non-operating PON system to the power recovery signal. And determine the wavelength of
The station side apparatus according to claim 8, wherein the forcible stop signal transmission unit transmits a power recovery signal to the terminal side communication apparatus using the wavelength signal obtained by the wavelength determination unit.

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