JP2013085055A - Ring-type network system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technique that can reduce wasteful electric power by shifting a port at which a communication fault is occurring to a power saving mode in a ring-type network system.SOLUTION: If a communication failure occurs, a ring node 12b will transmit a link down frame to a master node 12a. The link down frame is transmitted to the master node 12a via a ring node 12c, a ring node 12d, and a ring node 12e. The master node 12a transmits a transmission power cut-off frame F3 to the ring node 12b triggered by receiving the link down frame. The transmission power cut-off frame F3 is transmitted to the ring node 12b via the ring node 12e, ring node 12d, and ring node 12c. The ring node 12b shifts a ring port 16r at a side where the communication failure is occurring to a power saving mode triggered by receiving the transmission power cut-off frame F3.

Description

  The present invention relates to a ring network system.

  As a conventional technique, an electronic device equipped with a low power consumption mode is known (for example, see Patent Document 1).

  In the technique of Patent Document 1, when the physical layer (PHY LSI) transitions to the low power consumption mode, the optical transceiver also shifts to a standby state in the low power consumption mode in conjunction with the transition.

  For this reason, according to the technique of Patent Document 1, it is considered that by setting the optical transceiver to the standby state, the drive power supply voltage of various circuits is lowered, so that power consumption can be reduced.

JP 2002-118563 A

As a network system having a redundant network configuration, there is a ring network system in which network relay devices are connected in a ring shape.
In a ring network system, when a communication failure such as disconnection of a communication cable occurs, frames are not transmitted / received at the port where the communication failure has occurred. However, the conventional ring network system has a problem that power is wasted because a port in which a communication failure has occurred remains in a normal power mode.

  Accordingly, an object of the present invention is to provide a technique capable of shifting a port in which a communication failure has occurred in a ring network system to a power saving mode and reducing wasted power.

  In order to solve the above problems, a ring network system of the present invention is a ring network system in which a plurality of network relay devices are connected in a ring shape, and the plurality of network relay devices include a master node having a control port and A ring node having a ring port connected directly or indirectly to the control port of the master node, and when the ring node detects that a communication failure has occurred in the ring port, When the failure information is transmitted to the node, the master node transmits power saving mode transition command information to the ring node in which the communication failure has occurred, when the failure information is received. When the power saving mode transition command information is received, the ring in which the communication failure has occurred Over preparative usually ring network system to transition to the power mode and low power saving mode power consumption compared.

  According to the present invention, in a ring network system, a port in which a communication failure has occurred can be shifted to a power saving mode, and wasteful power can be reduced.

1 is a diagram illustrating a ring network system 10 according to a first embodiment. It is a block diagram which shows the structure of the master node 12a roughly. It is a block diagram which shows the structure of the ring node 12b schematically. It is a figure which shows the format of a control frame. It is a continuation figure explaining operation of ring type network system 10 (1/5). It is a continuation figure explaining operation of ring type network system 10 (2/5). It is a continuous figure explaining operation | movement of the ring type network system 10 (3/5). It is a continuation figure explaining operation of ring type network system 10 (4/5). It is a continuous figure explaining operation | movement of the ring type network system 10 (5/5). It is a continuous figure explaining operation | movement of the ring type network system 10 when a communication failure generate | occur | produces between a ring node and a ring node (1/2). It is a continuation figure explaining operation | movement of the ring type network system 10 when a communication failure generate | occur | produces between a ring node and a ring node (2/2). It is a figure which shows the ring type network system 10-2 of 2nd Embodiment. It is a block diagram which shows the structure of the 1st master node 12x roughly. It is a continuation figure explaining operation of ring type network system 10-2 (1/5). It is a continuation figure explaining operation of ring type network system 10-2 (2/5). It is a continuation figure explaining operation of ring type network system 10-2 (3/5). It is a continuous figure explaining operation | movement of the ring type network system 10-2 (4/5). It is a continuous figure explaining operation | movement of the ring type network system 10-2 (5/5). It is a continuous figure explaining operation | movement of the ring type network system 10-2 when a communication failure generate | occur | produces between a ring node and a ring node (1/2). It is a continuous diagram explaining the operation | movement of the ring type network system 10-2 when a communication failure generate | occur | produces between a ring node and a ring node (2/2).

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[First Embodiment]
FIG. 1 is a diagram illustrating a ring network system 10 according to the first embodiment.
The ring network system 10 includes five network relay devices 12 (12a to 12e) connected in a ring shape.

  The network relay device 12 is a device that relays frames at the layer 2 level using an OSI (Open Systems Interconnection) reference model, and is, for example, an Ethernet (registered trademark) switch.

  Each network relay device 12 is connected by, for example, one optical communication cable 14. A two-core type cable including two optical fibers can be applied to the optical communication cable 14.

  The network relay device 12 has a plurality of ports 16 to which the optical communication cable 14 is connected. The port 16 includes a transmission unit and a reception unit, and an optical fiber is connected to each of the transmission unit and the reception unit.

  The plurality of network relay devices 12 include a master node 12a having a master port 16m (control port, first control port) and a slave port 16s (control port, second control port). Since the master node 12a is a node having a master port 16m and a slave port 16s independently, it constitutes a single master.

  The plurality of network relay devices 12 include ring nodes 12b, 12c, 12d, and 12e having ring ports 16r that are directly or indirectly connected to the master port 16m and the slave port 16s of the master node 12a. Here, “directly connected” means that the ring port 16r is connected to the master port 16m and the slave port 16s of the master node 12a without going through the other ring port 16r. “Indirectly connected” means that the ring port 16r is connected to the master port 16m and the slave port 16s of the master node 12a via another ring port 16r.

[Master node]
FIG. 2 is a block diagram schematically showing the configuration of the master node 12a.
The master node 12 a includes a port 16, a PHY (physical layer) LSI (Large Scale Integration) 40, a relay module 50, a memory 60, and a ring control module 70.

〔port〕
A plurality of ports 16 are provided according to the number of ports provided in the master node 12 a, and each port 16 includes an optical transceiver 30. In the illustrated example, only two ports 16 are illustrated.

[Optical transceiver]
The optical transceiver 30 includes an electro-optical conversion unit (E / O (Electrical / Optical Converter)) 32 and an opto-electric conversion unit (O / E (Optical / Electrical Converter) unit) 34.

The electro-optical conversion unit 32 is configured by a light emitting element such as an LD (Laser Diode, laser diode), and is connected to the transmission unit of the port 16. The photoelectric conversion unit 34 includes a light receiving element such as a PD (Photo Diode), and is connected to the receiving unit of the port 16.
The optical transceiver 30 is an interface capable of shifting to a power saving mode, and for example, detachable QSFP + (Quad Small Form Factor Pluggable Plus) can be applied.

  Here, the “power saving mode” is a mode that consumes less power than the normal power mode (that is, the mode of power consumption in the normal state). In the “power saving mode”, although the mode contents differ depending on the performance and specifications of the optical transceiver 30, for example, accurate communication cannot be guaranteed by suppressing power consumption, but light is slightly received. It can be.

[PHY LSI]
The PHY LSI 40 performs processing such as encoding or decoding, and transmits a frame from the optical transceiver 30 to the relay module 50 or from the relay module 50 to the optical transceiver 30. The PHY LSI 40 includes a port operation unit 42, a communication failure detection unit 44, a communication failure notification unit 46, and a power mode setting unit 48.

[Port operation section]
The port operation unit 42 enables (enables) and disables (disables) each port 16 based on a predetermined command. Transmission / reception of the user frame is performed by the enabled port 16 and is not performed by the disabled port 16.

[Communication failure detection unit]
The communication failure detection unit 44 detects, for each port 16, whether the port 16 is in a normal state (link up) or a communication failure has occurred (link down). The communication failure detection unit 44 monitors (receives) light reception power at the optical transceiver 30 and determines that the reception power is less than a certain value when the reception power is above a certain value. In some cases, it is determined that a communication failure has occurred. Here, the “communication failure” includes not only a communication disabled state due to disconnection of the optical communication cable 14 but also a communication disabled state due to a failure of the network relay device 12 or a failure of the optical transceiver 30.

[Communication failure notification section]
When the communication failure detection unit 44 detects that a communication failure has occurred in any of the ports 16, the communication failure notification unit 46 sends a signal for notifying that a communication failure has occurred in the port 16 to the ring control module 70. Notification (output). In addition, when the communication failure notification unit 46 returns from the state where the communication failure has occurred to the normal state, the communication failure notification unit 46 notifies (outputs) a signal to that effect to the ring control module 70.

[Power mode setting section]
The power mode setting unit 48 sets the power mode (normal power mode or power saving mode) of the optical transceiver 30 in which a communication failure has occurred based on a command from the power mode management unit 78.
Specifically, when a signal to shift to the power saving mode is received from the power mode management unit 78, the signal to shift the optical transceiver 30 to the power saving mode and to shift to the normal power mode is received from the power mode management unit 78. If so, the optical transceiver 30 is shifted to the normal power mode.

[Relay module]
The relay module 50, in cooperation with the memory 60 and the ring control module 70, takes charge of the function of the MAC (Media Access Control) layer, and takes charge of the function of the MAC layer or higher as necessary.
The relay module 50 includes, for example, an ASIC (Application Specific Integrated Circuit), an FPGA (Field Programmable Gate Array), or the like. The relay module 50 has an input processing unit 52 and an output processing unit 54.

〔memory〕
The memory 60 is a storage device capable of reading and writing, and stores an FDB (Forwarding Data Base) 62. In the FDB 62, the port 16 number and the MAC address are registered in association with each other.

[Ring management DB]
The memory 60 stores a ring management DB (Data Base) 64. In the ring management DB 64, the master node 12a is set as the master node in the ring network system 10, the number of the master port 16m set as the first control port, and the second control port. The number of the slave port 16s, the status of the master port 16m and the slave port 16s, and the like are registered.

  Here, the states of the master port 16m and the slave port 16s registered in the ring management DB 64 include a forwarding state and a blocking state. The forwarding state is a state where both user frames and control frames can be transmitted and received, and the blocking state is a state where user frames cannot be transmitted and received, and control frames can be transmitted and received.

  The master port 16m belongs to the ring network system 10 and is a port set to the forwarding state when the ring network system 10 is in a normal state. The slave port 16s belongs to the ring network system 10 and is a port set to a blocking state when the ring network system 10 is in a normal state.

[Input processing unit]
The input processing unit 52 performs processing for setting the output destination port 16 and transmitting the frame to the output processing unit 54 while referring to the FDB 62 and the ring management DB 64 based on the transmission destination MAC address in the frame. Further, the input processing unit 52 performs processing for registering the source MAC address in the frame received from the PHY LSI 40 in the FDB 62 in association with the number of the port 16 that received the frame.

The input processing unit 52 performs processing for discarding the user frame received by the slave port 16s in the blocking state. That is, the slave port 16s in the blocking state is in a state where it does not substantially receive the user frame. Further, the input processing unit 52 performs a process of not setting the slave port 16s in the blocking state as the output destination of the user frame. That is, the slave port 16s in the blocking state does not transmit the user frame.
Further, when the frame received from the PHY LSI 40 is a control frame, the input processing unit 52 performs a process of transmitting the control frame to the ring control module 70.

[Output processing unit]
The output processing unit 54 transmits the frame received from the input processing unit 52 to the PHY LSI 40.

[Ring control module]
The ring control module 70 is constituted by a CPU (Central Processing Unit) and controls the ring protocol. The ring control module 70 includes a control frame generation unit 72, a control frame determination unit 74, a ring management unit 76, and a power mode management unit 78.

[Control frame generator]
The control frame generation unit 72 generates a control frame. The generated control frame is transmitted from one or both of the master port 16m and the slave port 16s through the relay module 50.

  As the destination of the control frame, a multicast address destined for all the network relay devices 12 belonging to the ring network system 10 is set. Therefore, each of the ring nodes 12 b to 12 e transmits a control frame received from one of the two ports 16 belonging to the ring network system 10 from the other port 16. That is, each ring node 12 b to 12 e transfers the control frame so as to flow along the ring network system 10.

  The control frames generated by the control frame generator 72 of the master node 12a include connection confirmation frames F1 and F2, and a transmission power cut frame (power saving mode shift command information) F3. The connection confirmation frame F1 indicates a connection confirmation frame transmitted from the master port 16m, and the connection confirmation frame F2 indicates a transmission transmitted from the slave port 16s. Further, the transmission power interruption frame F3 is a frame for shifting the ring port 16r in which the communication failure has occurred to the power saving mode.

[Control frame determination unit]
When the control frame is received by the master port 16m or the slave port 16s, the control frame is transmitted to the control frame determination unit 74 via the input processing unit 52.
The control frame determination unit 74 determines whether a control frame has been received. Then, the control frame determination unit 74 determines whether the received control frame is one of the connection confirmation frames F1 and F2 and the link down frame (failure occurrence information) F4. The link down frame F4 is a control frame transmitted by the ring nodes 12b, 12c, 12d, and 12e when a communication failure occurs.

[Ring Management Department]
The ring management unit 76 registers the states of the master port 16m and the slave port 16s in the ring management DB 64. Specifically, when the state of the slave port 16s is set to the blocking state, the ring management unit 76 registers the state of the slave port 16s as the blocking state in the ring management DB 64. When the state of the slave port 16s is set to the forwarding state, the ring management unit 76 registers the state of the slave port 16s as the forwarding state in the ring management DB 64.
When the ring network system 10 is in a normal state, the ring management unit 76 sets the state of the master port 16m to the forwarding state and the state of the slave port 16s to the blocking state.
In addition, when a communication failure occurs in the ring network system 10, the ring management unit 76 sets the slave port 16s to the forwarding state. Specifically, the ring management unit 76 sets the slave port 16s to the forwarding state based on the reception of the link down frame F4.
Further, when the communication failure of the ring network system 10 is recovered, the ring management unit 76 sets the slave port 16s to the blocking state. Specifically, the ring management unit 76 sets the slave port 16s to the blocking state based on the reception of the connection confirmation frame F1.
The ring management unit 76 has a function of clearing the contents of the FDB 62 when the communication path is changed due to a communication failure.

[Power Mode Management Department]
The power mode management unit 78 executes processing for managing the power mode (normal power mode or power saving mode) of the optical transceiver 30. Specifically, the power mode is managed based on the following conditions.

[When a failure occurs]
(1) When a communication failure occurs in the ring ports 16r of the ring nodes 12b to 12e, the link down frame F4 is transmitted from the ring nodes 12b to 12e. The power mode management unit 78 can recognize that a communication failure has occurred in the ring ports 16r of the ring nodes 12b to 12d based on the reception of the link down frame F4. In this case, the power mode management unit 78 causes the control frame generation unit 72 to generate the transmission power cutoff frame F3, and transmits the transmission power cutoff frame F3 to the ring nodes 12b to 12d in which the failure has occurred.

(2) When a communication failure occurs in the master port 16m or the slave port 16s of the master node 12a, the communication failure notification unit 46 notifies that the communication failure has occurred. A signal to shift to the power saving mode is transmitted to the power mode setting unit 48.

[When recovering from a failure]
(3) When the communication failure at the master port 16m or the slave port 16s of the master node 12a is recovered, the communication failure notification unit 46 notifies that the communication failure has been recovered, so the power mode management unit 78 Then, a signal for shifting to the normal power mode is transmitted to the power mode setting unit 48.

[Ring node]
FIG. 3 is a block diagram schematically showing the configuration of the ring node 12b. In the following description, the same configuration as that of the master node 12a is denoted by the same name or symbol, and the description thereof is omitted as appropriate. The configuration of the ring nodes 12c to 12e is the same as that of the ring node 12b.

[Ring management DB]
The ring management DB 66 of the ring node 12b registers that the ring node 12b is set as a ring node in the ring network system 10 and the number of the ring port 16r set as a ring port.

[Control frame generator]
The control frame generation unit 80 generates a control frame. The control frame generated by the control frame generation unit 80 of the ring node 12b is a link down frame F4. The link down frame F4 is a frame for notifying the master node 12a of information on the ring port 16r in which a communication failure has occurred.

[Power Mode Management Department]
The power mode management unit 82 executes processing for managing the power mode (normal power mode or power saving mode) of the optical transceiver 30. Specifically, the power mode is managed based on the following conditions.

[When a failure occurs]
(1) When a communication failure occurs in the ring port 16r of the ring node 12b, since the communication failure notification unit 46 notifies that the communication failure has occurred, the power mode management unit 82 uses the control frame generation unit 80 generates a link-down frame F4, and transmits the link-down frame F4 to the master node 12a.
(2) When the link-down frame F4 is transmitted to the master node 12a, the transmission power cutoff frame F3 is transmitted from the master node 12a this time, so that the power mode management unit 82 receives the received transmission power cutoff frame F3. Based on this, a signal for shifting to the power saving mode is transmitted to the power mode setting unit 48.

[When recovering from a failure]
(3) When the communication failure at the ring port 16r of the ring node 12b is recovered, the communication failure notification unit 46 notifies that the communication failure has been recovered, so the power mode management unit 82 sets the power mode. A signal for shifting to the normal power mode is transmitted to the unit 48.

FIG. 4 is a diagram showing the format of the control frame.
The control frame includes a DA (Destination Address) area, an SA (Source Address) area, other areas, a frame type area, a message type area, a port type area, and the like.

The DA area stores the MAC address of the transmission destination, and the SA area stores the MAC address of the transmission source.
In the other area, for example, a VID (Virtual LAN ID) indicating a virtual network identification number, a RingID indicating a ring network identification number, and the like are stored.

  A value indicating the type of frame is stored in the frame type area. For example, the value “1” is stored for the connection confirmation frame F1, the value “2” is stored for the connection confirmation frame F2, and the value “3” is stored for the other control frames. .

  In the message type area, values indicating the types of other control frames are stored. For example, a value of “1” is stored for the transmission power cut-off frame F3, and a value of “2” is stored for the link-down frame F4.

  In the port type area, when it is necessary to specify a predetermined port, a value (failure occurrence port information) for specifying the predetermined port is stored. For example, the value “1” is stored in the ring node 16r of the ring port 16r close to the master port 16m, and the value of “2” is stored in the ring port 16r close to the slave port 16s. For the port type area, the port can also be specified by storing the identification number of each port.

  For this reason, in the link-down frame F4, it is possible to specify its own transmission source information by the SA area, and it is possible to specify the ring port 16r where the communication failure has occurred by the port type area. Further, in the transmission power interruption frame F3, the transmission destination information can be specified by the DA area, and the ring port 16r where the communication failure has occurred can be specified by the port type area. Therefore, by referring to the link-down frame F4 and the transmission power interruption frame F3, it is possible to grasp which port of which node has a communication failure.

[Overall operation]
Hereinafter, operations of the master node 12a and the ring nodes 12b to 12e in the ring network system 10 will be described.

  5 to 9 are continuous diagrams for explaining the operation of the ring network system 10. 5 to 9 show a series of operations until the ring network system 10 changes from a normal state to an abnormal state and the abnormal state is recovered.

[Normal (1)]
As shown in FIG. 5A, the master node 12a transmits a connection confirmation frame F1 and a connection confirmation frame F2 from the master port 16m and the slave port 16s, respectively.
The connection confirmation frame F1 is sequentially transferred by the ring node 12b, the ring node 12c, the ring node 12d, and the ring node 12e, and is received by the slave port 16s of the master node 12a. Similarly, the connection confirmation frame F2 is sequentially transferred by the ring node 12e, the ring node 12d, the ring node 12c, and the ring node 12b, and is received by the master port 16m. The master node 12a can determine that the ring network system 10 is operating normally when the connection confirmation frames F1 and F2 are periodically received.

[Normal (2)]
As shown in FIG. 5B, at the normal time, the master port 16m of the master node 12a is in the forwarding state, and the slave port 16s is in the blocking state.
Therefore, when the ring network system 10 is in a normal state, the user frame UF transmitted from the outside of the ring node 12c passes through the ring node 12c, the ring node 12b, and the master node 12a, and is transmitted to the master node 12a. Forwarded to the outside. On the other hand, all the user frames UF that have passed through the ring node 12d and the ring node 12e are discarded at the slave port 16s because the slave port 16s of the master node 12a is in a blocking state.

[When communication failure occurs (part 1)]
As shown in FIG. 6, it is assumed that a communication failure occurs between the master node 12a and the ring node 12b.
The ring node 12b detects the occurrence of a communication failure and transmits a link down frame F4 toward the master node 12a. The link down frame F4 is transmitted to the master node 12a via the ring node 12c, the ring node 12d, and the ring node 12e. The master node 12a sets the slave port 16s to the forwarding state based on the reception of the link down frame F4. Thereby, the user frame transmitted from the outside of the ring node 12c is transferred to the outside of the master node 12a via the ring node 12c, the ring node 12d, the ring node 12e, and the master node 12a ( (See FIG. 7B).

[When communication failure occurs (part 2)]
As shown in FIG. 7A, the master node 12a transmits a transmission power interruption frame F3 toward the ring node 12b when the link-down frame F4 is received. The transmission power interruption frame F3 is transmitted to the ring node 12b via the ring node 12e, the ring node 12d, and the ring node 12c.

[When communication failure occurs (part 3)]
As shown in FIG. 7B, the ring node 12b shifts the ring port 16r on the communication failure side to the power saving mode when receiving the transmission power interruption frame F3. The master node 12a shifts the master port 16m to the power saving mode. Note that the ports that have shifted to the power saving mode are colored black.

  Here, the master node 12a and the ring nodes 12b to 12e can erase the contents of the FDB 62 after a predetermined time, for example, after shifting to the power saving mode. The reason for erasing the contents of the FDB 62 after shifting to the power saving mode is that it is necessary to transmit the transmission power interruption frame F3 before it becomes impossible to identify the relay device in which the communication failure has occurred.

[At the time of restoration (part 1)]
As shown in FIG. 8A, it is assumed that a portion where a communication failure has occurred is recovered. Here, “recovery” means that the communication failure is solved for some reason. For example, if the optical communication cable 14 is firmly inserted, or if the optical communication cable 14 is disconnected, the optical communication cable 14 14 is replaced, or if the optical transceiver 30 is faulty, the communication fault is solved by replacing the optical transceiver 30 with a new one.

[At the time of recovery (part 2)]
As shown in FIG. 8B, when the communication failure detection unit 44 detects recovery of the communication failure, the master node 12a and the ring node 12b shift the port 16 in the power saving mode to the normal power mode.

[At the time of recovery (part 3)]
As shown in FIG. 9A, when the master port 16m of the master node 12a shifts from the power saving mode state to the normal power mode, it once enters the listening state. Here, the listening state is a state in which user frames are not transmitted / received, but control frames are transmitted / received. In order to recover from the listening state to the forwarding state, the recovery can be performed manually or automatically. When recovering manually, it is possible to recover from the listening state to the forwarding state by inputting a command to the master node 12a or the like with a predetermined input device. In the case of automatic recovery, the recovery processing can be automatically performed by setting the specification to recover from the listening state to the forwarding state after a lapse of a certain time after shifting to the listening state.

[At the time of recovery (part 4)]
As shown in FIG. 9B, when the restoration work is completed, the master port 16m is set from the listening state to the forwarding state. Further, based on the fact that the connection confirmation frame F1 transmitted from the master port 16m is received by the slave port 16s, the slave port 16s is set from the forwarding state to the blocking state. As a result, the ring network system 10 returns to the original (initial) state.

  The above description is an operation example when a communication failure occurs between the master node 12a and the ring node 12b, but when a communication failure occurs between the ring node and the ring node, Become. Note that a description of the same parts as those of the operation example described above is omitted.

  10 and 11 are continuous diagrams for explaining the operation of the ring network system 10 when a communication failure occurs between the ring nodes.

[When communication failure occurs (part 1)]
As shown in FIG. 10A, it is assumed that a communication failure occurs between the ring node 12b and the ring node 12c.
The ring node 12b detects the occurrence of a communication failure and transmits a link down frame F4 toward the master node 12a. Further, the ring node 12c transmits a link down frame F4 toward the master node 12a. The link down frame F4 transmitted by the ring node 12c is transmitted to the master node 12a via the ring node 12d and the ring node 12e.
Therefore, the master node 12a receives the link down frame F4 at both the master port 16m and the slave port 16s. The master node 12a sets the slave port 16s to the forwarding state based on the reception of the link down frame F4.

[When communication failure occurs (part 2)]
As shown in FIG. 10B, the master node 12a transmits a transmission power interruption frame F3 toward the ring node 12b and the ring node 12c when the link-down frame F4 is received. The transmission power interruption frame F3 includes a frame that is directly transmitted to the ring node 12b and a frame that is transmitted to the ring node 12b via the ring node 12e and the ring node 12d.

[When communication failure occurs (part 3)]
As illustrated in FIG. 11, the ring node 12b and the ring node 12c shift the ring port 16r on the communication failure side to the power saving mode when receiving the transmission power cut frame F3. Note that the recovery procedure after shifting to the power saving mode is the same as the recovery procedure described above.

Thus, according to the first embodiment, there are the following effects.
(1) Since the ring nodes 12b and 12c shift the ring port 16r to the power saving mode when receiving the transmission power interruption frame F3 from the master node 12a, the ring port 16r in which a communication failure has occurred. Can be shifted to the power saving mode. For this reason, only the ring port 16r in which a communication failure has occurred can be shifted to the power saving mode pinpointly, and wasteful power can be efficiently reduced. Since the ring port 16r that has been shifted to the power saving mode is in a state where communication cannot be performed in the first place due to the occurrence of a communication failure, there is no influence on communication even if the ring port 16r is shifted to the power saving mode.

(2) The ring port 16r in which the communication failure has occurred does not turn off the power but shifts to the power saving mode. For this reason, when recovering from a communication failure, it is possible to quickly shift to the normal power mode, and to shorten the recovery time for the communication failure of the entire system. The specific recovery time depends on the performance of the optical transceiver 30. For example, when QSFP + is adopted for the optical transceiver 30, “about 2 seconds” is required to shift from the power-off state to the normal power mode. However, since it takes about 100 ms to shift from the power saving mode to the normal power mode, a quick recovery process can be realized.

(3) When a failure occurs, the ring nodes 12b and 12c transmit the link down frame F4 to the master node 12a, and after receiving the transmission power interruption frame F3 from the master node 12a, shift to the power saving mode. That is, the ring nodes 12b and 12c do not operate on their own, but shift to the power saving mode after receiving an instruction from the master node 12a. For this reason, when a failure occurs, it is possible to provide a system that is controlled by collective management at the master node 12a. On the other hand, at the time of recovery, the ring nodes 12b and 12c do not wait for an instruction from the master node 12a but voluntarily shift to the normal power mode. Thereby, a quicker recovery process can be realized at the time of recovery.

(4) On the other hand, regarding the master node 12a, the master port 16m voluntarily shifts to the power saving mode or shifts to the normal power mode both when a failure occurs and when it recovers. This is because the master node 12a corresponds to a control device that performs overall control of the ring network system 10, and the processing procedure and control contents are complicated by directly managing the power mode. It is avoiding that.

[Second Embodiment]
FIG. 12 is a diagram illustrating a ring network system 10-2 according to the second embodiment.
The ring network system 10-2 of the second embodiment is different from the ring network system 10 of the first embodiment in that it includes two master nodes.

Specifically, the ring network system 10-2 includes a first master node 12x (network relay device 12) having a master port 16m (first control port). The ring network system 10-2 includes a second master node 12y (network relay device 12) having a slave port 16s (second control port).
For this reason, the first master node 12x and the second master node 12y are nodes each having a master port 16m and a slave port 16s, and thus constitute a distributed master. The first master node 12x and the second master node 12y are connected by an interconnection port 16i. Other configurations are the same as those in the first embodiment.

FIG. 13 is a block diagram schematically showing the configuration of the first master node 12x.
The configuration of the second master node 12y is the same as that of the first master node 12x except that the control port setting and operation are different. For this reason, illustration of the second master node 12y is omitted, and only differences from the first master node 12x will be described. Of the configuration of the first master node 12x, the description of the configuration common to the master node 12a of the first embodiment is omitted. Further, the configuration of the ring nodes 12b, 12c and the like is the same as the configuration of the ring nodes in the ring network system 10 of the first embodiment, and thus description thereof is omitted.

[Ring management DB]
In the case of the first master node 12x, the port connected to the ring node 12b is set as the master port 16m in the ring management DB 68, and the forwarding state is registered as the state of the master port 16m. In the ring management DB 68, a port connected to the second master node 12y is set as an interconnection port 16i.

  In the case of the second master node 12y, the port connected to the ring node 12c is set as the slave port 16s in the ring management DB, and the blocking state is registered as the state of the slave port 16s. In the ring management DB, a port connected to the first master node 12x is set as an interconnection port 16i.

[Overall operation]
Hereinafter, operations of the first master node 12x, the second master node 12y, the ring node 12b, and the ring node 12c in the ring network system 10-2 will be described.

  14 to 18 are continuous diagrams for explaining the operation of the ring network system 10-2. 14 to 18 show a series of operations until the ring network system 10-2 changes from a normal state to an abnormal state and the abnormal state is recovered.

[Normal (1)]
As shown in FIG. 14A, the first master node 12x transmits a connection confirmation frame F1 from the master port 16m.
The connection confirmation frame F1 is sequentially transferred by the ring node 12b and the ring node 12c, and is received by the slave port 16s of the second master node 12y.

On the other hand, the second master node 12y transmits a connection confirmation frame F2 from the slave port 16s.
The connection confirmation frame F2 is sequentially transferred by the ring node 12c and the ring node 12b and received by the master port 16m. When the first master node 12x and the second master node 12y regularly receive the connection confirmation frames F1 and F2, it can be determined that the ring network system 10-2 is operating normally.

[Normal (2)]
As shown in FIG. 14B, in the normal state, the master port 16m of the first master node 12x is in the forwarding state, and the slave port 16s of the second master node 12y is in the blocking state.
Therefore, when the ring network system 10-2 is in a normal state, the user frame UF transmitted from the outside of the ring node 12b is transferred to the outside of the first master node 12x via the ring node 12b. The On the other hand, the user frame UF that has passed through the ring node 12b and the ring node 12c is all discarded at the slave port 16s because the slave port 16s of the second master node 12y is in a blocking state.

[When communication failure occurs (part 1)]
As shown in FIG. 15, a case is assumed in which a communication failure occurs between the first master node 12x and the ring node 12b.
The ring node 12b detects the occurrence of a communication failure and transmits a link down frame F4 toward the second master node 12y. The link down frame F4 is transmitted to the second master node 12y via the ring node 12c. Based on the reception of the link down frame F4, the second master node 12y sets the slave port 16s from the blocking state to the forwarding state. Thereby, the user frame transmitted from the outside of the ring node 12b is transferred to the outside of the first master node 12x via the ring node 12b, the ring node 12c, the second master node 12y, and the first master node 12x. (See FIG. 16B).

[When communication failure occurs (part 2)]
As shown in FIG. 16A, the second master node 12y transmits a transmission power interruption frame F3 toward the ring node 12b when the link-down frame F4 is received. The transmission power interruption frame F3 is transmitted to the ring node 12b via the ring node 12c.

[When communication failure occurs (part 3)]
As shown in FIG. 16B, the ring node 12b shifts the ring port 16r on the communication failure side to the power saving mode when receiving the transmission power interruption frame F3. The first master node 12x shifts the master port 16m to the power saving mode.

  Similarly, after the first master node 12x, the second master node 12y, and the ring nodes 12b and 12c are shifted to the power saving mode, the contents of the FDB 62 are deleted after a predetermined time, for example.

[At the time of restoration (part 1)]
As shown in FIG. 17A, it is assumed that a portion where a communication failure has occurred is recovered.

[At the time of recovery (part 2)]
As shown in FIG. 17B, when the first master node 12x and the ring node 12b detect recovery by the communication failure detection unit 44, the first master node 12x and the ring node 12b shift the port 16 in the power saving mode to the normal power mode.

[At the time of recovery (part 3)]
As shown in FIG. 18A, when the master port 16m of the first master node 12x shifts from the power saving mode state to the normal power mode, the master port 16m once enters the listening state.

[At the time of recovery (part 4)]
As shown in FIG. 18B, when the restoration work is completed, the master port 16m is set to the forwarding state. Further, based on the fact that the connection confirmation frame F1 transmitted from the master port 16m is received by the slave port 16s, the slave port 16s of the second master node 12y is set from the forwarding state to the blocking state. As a result, the ring network system 10-2 returns to the original (initial) state.

  The above description is an operation example when a communication failure occurs between the first master node 12x and the ring node 12b, but when a communication failure occurs between the ring node and the ring node, the following operation is performed. An example. In addition, although description is abbreviate | omitted about the part similar to the operation example demonstrated previously, in the following operation examples, it is the example which added the new ring node 12d between the 1st master node 12x and the ring node 12b. explain.

  19 and 20 are continuous diagrams for explaining the operation of the ring network system 10-2 when a communication failure occurs between the ring nodes.

[When communication failure occurs (part 1)]
As shown in FIG. 19A, it is assumed that a communication failure occurs between the ring node 12b and the ring node 12d.
The ring node 12d detects the occurrence of a communication failure, and transmits a link down frame F4 toward the first master node 12x. The ring node 12b detects the occurrence of a communication failure and transmits a link down frame F4 toward the second master node 12y. The link down frame F4 transmitted by the ring node 12b is transmitted to the second master node 12y via the ring node 12c.
Based on the reception of the link down frame F4, the second master node 12y sets the slave port 16s from the blocking state to the forwarding state.

[When communication failure occurs (part 2)]
As shown in FIG. 19B, the first master node 12x transmits a transmission power interruption frame F3 toward the ring node 12d when receiving the link-down frame F4. In addition, the second master node 12y transmits the transmission power cut frame F3 toward the ring node 12b when the link down frame F4 is received. The transmission power interruption frame F3 transmitted by the second master node 12y is transmitted to the ring node 12b via the ring node 12c.

[When communication failure occurs (part 3)]
As illustrated in FIG. 20, the ring node 12b and the ring node 12d shift the ring port 16r on the communication failure side to the power saving mode when receiving the transmission power cut frame F3. Note that the recovery procedure after shifting to the power saving mode is the same as the recovery procedure described above.

  As described above, according to the second embodiment, even when the distributed master is adopted as the master node, only the port 16 in which the communication failure has occurred is accurately set to the power saving mode, similarly to the first embodiment. The useless power can be efficiently reduced.

The present invention can be implemented with various modifications and substitutions without being limited to the above-described embodiment.
For example, the number of network relay devices configuring the ring network system, the number of ports, and the like are shown as examples, and are not limited thereto.

DESCRIPTION OF SYMBOLS 10,10-2 Ring type network system 12 Network relay apparatus 12a Master node 12b-12e Ring node 12x 1st master node 12y 2nd master node 16 port 16m Master port 16s Slave port 16r Ring port 30 Optical transceiver 40 PHY LSI
50 relay module 60 memory 70 ring control module

Claims (7)

A ring network system in which a plurality of network relay devices are connected in a ring shape,
The plurality of network relay devices are:
A master node having a control port;
A ring node having a ring port connected directly or indirectly to the control port of the master node,
The ring node is
When it is detected that a communication failure has occurred in the ring port, the failure occurrence information is transmitted to the master node,
The master node is
When receiving the failure occurrence information, transmit power saving mode transition command information to the ring node where the communication failure has occurred,
The ring node is
A ring network system that, when receiving the power saving mode shift command information, shifts the ring port in which the communication failure has occurred to a power saving mode that consumes less power than a normal power mode. The ring network system according to claim 1,
The ring node is
A ring network system that shifts from the power saving mode to the normal power mode when it is detected that a communication failure occurring in the ring port that has shifted to the power saving mode is recovered. The ring network system according to claim 1 or 2,
The master node is
A ring network system that shifts the control port in which the communication failure has occurred to the power saving mode when detecting that a communication failure has occurred in the control port. In the ring network system according to any one of claims 1 to 3,
The master node is
A ring network system that shifts from the power saving mode to the normal power mode when it is detected that a communication failure occurring in a control port that has shifted to the power saving mode is recovered. In the ring network system according to any one of claims 1 to 4,
The master node and the ring node are:
A ring network system comprising a transfer database and erasing the contents of the transfer database after shifting to the power saving mode. In the ring network system according to any one of claims 1 to 5,
The master node is
A node having the first control port as the control port set to the forwarding state and the second control port as the control port set to the blocking state at the normal time, or the first control port and the first control port It consists of multiple nodes that have two control ports individually,
A ring network system that sets the second control port from a blocking state to a forwarding state when the communication failure occurs, and sets the second control port from a forwarding state to a blocking state when the communication failure is recovered. In the ring network system according to any one of claims 1 to 6,
The ring node is
As the failure occurrence information, transmitting information including own transmission source information and failure occurrence port information for identifying a ring port in which a communication failure has occurred,
The master node is
A ring network system that transmits, as the power saving mode shift command information, a command for shifting to a power saving mode for a ring port in which a communication failure has occurred.

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