JP2007235540A - Terminating device of bus-type lan - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a bus-type LAN terminating device capable of notifying faults in a link between clients while link is retained in a relay, even if a plurality of the bus-type LAN terminating devices are connected in multi-stage so as to conduct relaying. <P>SOLUTION: The terminating device comprises a setting means for setting up the device as the one for relaying or the one for termination within a bus-type LAN. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a termination device for a bus type LAN (Local Area Network), and more particularly to a termination device used in a bus type LAN such as Ethernet (registered trademark), and more particularly to termination of a bus type LAN characterized by control of link disconnection. Relates to the device.

  Conventionally, a bus type LAN (Local Area Network) such as Ethernet (registered trademark) has been widely used, and various structures of termination devices have been proposed.

  For example, Patent Document 1 discloses an example of an Ethernet termination device.

  An example of an alarm transfer method in a conventional Ethernet termination device will be described with reference to FIG.

  In FIG. 6, the frame reception unit 611 of the Ethernet termination device 610 receives a frame from the client device 630. In addition, the frame reception unit 611 detects link abnormality.

  If the frame reception unit 611 detects a link abnormality, the frame reception unit 611 notifies the alarm transmission unit 613 of the Ethernet termination device 610 to that effect.

  The encapsulation unit 612 of the Ethernet termination device 610 performs frame encapsulation from the frame reception unit 611.

  The alarm transmission unit 613 of the Ethernet termination device 610 writes the fact of detection of the link abnormality notified from the frame reception unit 611 in a part of the overhead area of the frame encapsulated by the encapsulation unit 612, and transmits this To notify the opposite Ethernet termination device 620 of the link abnormality.

  The alarm reception unit 624 of the Ethernet termination device 620 receives the link abnormality transmitted from the alarm transmission unit 613 of the Ethernet termination device 610 and notifies the frame transmission unit 621 of the Ethernet termination device 620 of the fact.

  The decapsulation unit 625 of the Ethernet termination device 620 decapsulates the frame received from the Ethernet termination device 610.

  The frame transmission unit 621 of the Ethernet termination device 620 transmits a normal frame to the client device 640.

  The frame transmission unit 621 of the Ethernet termination device 620 receives the link abnormality notification received by the alarm reception unit 624 from the alarm reception unit 624 and forcibly disconnects the link with the client device 640 based on the notification.

Japanese Patent Laid-Open No. 2003-110585

  However, the conventional bus LAN termination device as described above has the following problems.

  The first problem is that in the above-described Ethernet termination device, the Ethernet termination device 620 disconnects the link with the client device 640 by the link abnormality notification from the opposing Ethernet termination device 610. When there is an Ethernet termination device for relay between the termination device 610, the link cannot be maintained even in the relay section.

  That is, when trying to maintain the link in the relay section, there is no abnormality in the relay section, so there is a problem that the link abnormality notification cannot be transmitted and the link abnormality notification in the terminal section cannot be performed.

  The second problem is that, conventionally, since the link is always disconnected, when the Ethernet termination device is connected in multiple stages, an alarm is notified in all sections, and it is difficult to monitor.

  In other words, if the oppositely connected device has the function of forcibly linking its own device by the opposite side link disconnection notification, the link will be disconnected even in the section used as a relay section if it is connected in multiple stages to relay. There was a problem of doing.

  The present invention has been made in view of the above points. Even when a bus LAN termination device is connected in multiple stages so as to relay, a link error is maintained between clients while maintaining the link in the relay section. It is an object of the present invention to provide a bus-type LAN termination device that can notify the above.

  The present invention is characterized by comprising setting means for setting whether to use as a relay or as a terminal in a bus type LAN.

  In addition, the present invention is characterized in that a transmission unit that varies transmission data according to a setting state by the setting unit is provided.

  Further, the present invention is characterized by comprising receiving means for differently processing received data according to the setting state by the setting means.

  In addition, the present invention includes an alarm receiver that receives an alarm from another bus LAN termination device, and is set by the setting means to be used for relay in the bus LAN. The processing when the alarm is received by the alarm receiving unit is different depending on whether it is set to be used for termination.

  The present invention further includes an alarm receiving unit for receiving information indicating that the link with the client device is abnormal from a terminal device of another bus type LAN connected to the client device, and the setting unit includes the bus type LAN. If it is set to be used for relaying in the network, information indicating that the link is abnormal is transmitted by the transmission means, and if it is set to be used for termination in the bus type LAN, Is further provided with a link cutting means for cutting the link with the client apparatus connected as the terminal.

  Further, the present invention is characterized in that the bus type LAN is an Ethernet and the termination device of the bus type LAN is an Ethernet termination device.

  Further, the alarm transfer system of the present invention is characterized in that the data to be transferred is made different based on whether it is used for relaying or used for termination in a bus type LAN.

  Further, according to the present invention, in a program of a termination device that operates on a computer for operation as a bus LAN termination device, whether the computer is used for relay or termination in the bus LAN A program that functions as a setting means for setting, and a program that functions as an alarm receiving unit that receives information indicating that there is a link error with the client device from another bus-type LAN termination device connected to the client device If the setting means sets that the relay is used in the bus type LAN, the transmission means transmits information indicating that the link is abnormal, and the bus type LAN uses the information for termination. If it is set to be used, link the client device connected as the end Characterized in that a program to function as a cross linking cutting means.

  According to the present invention, even when a bus-type LAN termination device is connected in multiple stages so as to relay, the bus type can notify link abnormality between clients while maintaining the link in the relay section. A LAN termination device can be provided.

  More specifically, the present invention has the following effects.

  That is, the first effect is that since the link is maintained in the relay section, it is easy to identify the section where the failure first occurs.

  The second effect is that since the link is maintained in the relay section, alarm notifications can be reduced for the monitored system.

  Next, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a block diagram showing a configuration of a LAN system using an embodiment of a bus LAN termination device according to the present invention.

  In the following description, an Ethernet (registered trademark) termination device will be described as an example of a termination device of a bus type LAN (Local Area Network).

  The Ethernet termination device according to the present embodiment is characterized in that the number of alarms that are issued when a link abnormality occurs in the oppositely connected Ethernet termination device during multistage connection is reduced.

  As shown in FIG. 1, the Ethernet termination device 120 is connected to the client device 110, the Ethernet termination device 150 is connected to the client device 160, and the Ethernet termination device 150 is connected between the Ethernet termination device 120 and the Ethernet termination device 150. 130 and Ethernet terminator 140 relay.

  The client device 110 and the Ethernet termination device 120 are connected by a client interface 111 and a client interface 112.

  The Ethernet termination device 120 and the Ethernet termination device 130 are connected by an aggregate interface 121 and an aggregate interface 122.

  The Ethernet termination device 130 and the Ethernet termination device 140 are connected by a client interface 131 and a client interface 132.

  The Ethernet termination device 140 and the Ethernet termination device 150 are connected by an aggregate interface 141 and an aggregate interface 142.

  The Ethernet termination device 150 and the client device 160 are connected by a client interface 151 and a client interface 152.

  The Ethernet termination device 120 detects a link abnormality with the client device 110 and notifies the Ethernet termination device 130 of the link abnormality through the aggregate interface 121.

  The Ethernet termination device 130 that has received the link abnormality notification detects the reception of the link abnormality notification from the Ethernet termination device 120 by the aggregate interface 121, generates a special frame in response thereto, and the client interface 131 causes the Ethernet termination device 130 to receive the link abnormality notification. The generated special frame is transmitted to the device 140.

  Upon receiving this special frame, the Ethernet termination device 140 detects the reception of the special frame from the Ethernet termination device 130 by the client interface 131, and accordingly, the aggregate interface 141 causes the link termination error to the Ethernet termination device 150. Make a notification.

  The Ethernet termination device 150 that has received this link abnormality notification detects the reception of the link abnormality notification from the Ethernet termination device 140 by the aggregate interface 141, and in response to this, the link of the client interface 151 with the client device 160 is detected. Turn off.

  In this manner, in this embodiment, the link state of the relay section is maintained, so that the alarms that are generated can be reduced, and maintenance can be facilitated thereby.

  In the relay section, the link disconnection function based on the link disconnection notification is stopped, a special frame is output, and only the client is disconnected.

  FIG. 2 is a block diagram showing the internal structure of the Ethernet terminator used in the embodiment shown in FIG. The Ethernet termination device 210 and the Ethernet termination device 220 have the same configuration.

  In FIG. 2, the frame termination unit 211 of the Ethernet termination device 210 has a frame reception unit and a frame transmission unit, and the frame reception unit of the frame termination unit 211 receives a frame from the client device 230.

  The frame reception unit of the frame termination unit 211 monitors the link with the client device 230, and notifies the alarm transmission unit 214 of the Ethernet termination device 210 when the link abnormality occurs.

  The special frame termination unit 212 of the Ethernet termination device 210 terminates the special frame received from the CPU client interface, detects and discards the special frame, and notifies the alarm transmission unit 214 of the contents of the special frame.

  The encapsulation unit 213 of the Ethernet termination device 210 encapsulates data received by the client interface.

  The alarm transmission unit 214 of the Ethernet termination device 210 responds to the special frame reception information notified from the special frame termination unit 212 when the CPU unit 218 sets that this device is installed in the relay section. The link abnormality information is added to the overhead of the frame encapsulated by the encapsulation unit 213.

  Further, the alarm transmission unit 214 detects the link abnormality notified from the frame reception unit of the frame termination unit 211 and adds link abnormality information to the overhead of the frame encapsulated by the encapsulation unit 213.

  The alarm receiving unit 225 of the Ethernet termination device 220 detects the information added by the alarm transmission unit 214 of the Ethernet termination device 210 and notifies the frame generation unit 227 or the frame transmission unit 221 of the link abnormality. Which block (the frame generation unit 227 or the frame transmission unit 221) is notified is a setting in the CPU unit 228 that sets whether this apparatus is installed in a relay section or a terminal point by. Based on this setting, the alarm receiving unit 225 notifies the frame generation unit 227 when the relay section is set, and notifies the frame termination unit 221 when the termination point is set.

  The decapsulation unit 226 of the Ethernet termination device 220 decapsulates the data encapsulated by the encapsulation unit 213 of the Ethernet termination device 210.

  The frame generation unit 227 of the Ethernet termination device 220 generates a special frame based on the link abnormality notification of the Ethernet termination device 210 notified from the alarm reception unit 225, and transmits the special frame to the frame transmission unit of the frame termination unit 221.

  The frame transmission unit of the frame termination unit 221 forcibly disconnects the link with the client device 240 based on the link abnormality notification of the Ethernet termination device 210 notified from the alarm reception unit 225.

  As described above, the CPU unit 228 sets whether the apparatus is installed in the relay section or the terminal point based on, for example, an external input. This setting result is stored in a storage means (not shown), for example, and is referred to as necessary.

  FIG. 3 is a diagram illustrating a configuration example of a special frame generated by the frame generation unit of the Ethernet termination device illustrated in FIG.

  As shown in FIG. 3, the frame configuration of this special frame is an Ethernet frame, a broadcast address is set as the transmission destination MAC address 310, and a unique MAC address of the own apparatus is set as the transmission source MAC address 320. . The length 330 indicating the frame length is fixed to 64 bytes.

  FIG. 4 is a diagram illustrating a configuration example of an encapsulated frame generated by the encapsulation unit of the Ethernet termination device illustrated in FIG.

  As shown in FIG. 4, information indicating that the link is abnormal is set using a partial area of the frame overhead 410, and “1” is set in the LINK 420 when the link is abnormal, and “0” is set when the link is normal. To do.

  Next, the operation of the Ethernet termination apparatus according to this embodiment will be described in more detail with reference to FIG.

  FIG. 5 is a block diagram showing a connection configuration example of the Ethernet termination device used in the embodiment shown in FIG.

  In each of the Ethernet termination devices 510, 520, 540, and 550, the CPU unit 519, 529, 549, and 559 determines whether the own device is installed in a relay section or a termination point in the LAN. Done in advance. In the example of FIG. 5, the termination points are set for the Ethernet termination devices 510 and 550, and the relay point settings are set for the Ethernet termination devices 520 and 540. This setting is set in each alarm transmission unit and each alarm reception unit from each CPU unit of each Ethernet termination device, for example.

  For example, when an abnormality occurs in the link between the Ethernet termination device 510 and the client device 530, a link abnormality is detected by the frame reception unit 511 of the Ethernet termination device 510, and this link abnormality is notified to the alarm transmission unit 514.

  As described above, when the link abnormality is detected by the frame receiving unit 511, the bit of the LINK 420 of the frame shown in FIG. 4 is set to “1”. The alarm transmission unit 514 transmits this frame.

  Subsequently, the alarm receiving unit 525 of the Ethernet termination device 520 checks the overhead of the frame received from the Ethernet termination device 510.

  When the bit of the LINK 420 of the frame shown in FIG. 4 is “1”, since the setting of the Ethernet termination device 520 is the setting of the relay section here, the link generation is detected by the frame generation unit 527 of the Ethernet termination device 520. Notify you.

  The frame generation unit 527 generates a special frame having the configuration shown in FIG. 3 based on the notified link abnormality. When the link reception is notified from the alarm reception unit 525, the special frame is transmitted to the frame transmission unit 521. Send to.

  The frame transmission unit 521 transmits the special frame generated by the frame generation unit 527 to the Ethernet termination device 540.

  The frame receiving unit 541 of the Ethernet termination device 540 that has received the special frame transmits the special frame as it is to the special frame termination unit 542.

  The special frame termination unit 542 notifies the alarm transmission unit 544 that a special frame has been received. The special frame termination unit 542 discards the received special frame.

  The alarm transmission unit 544 notified of the reception of the special frame is shown in FIG. 4 based on the link abnormality notified from the special frame termination unit 542, similarly to the processing of the alarm transmission unit 514 of the Ethernet termination device 540. The bit of the LINK 420 of the frame is set to “1”. The alarm transmission unit 514 transmits this frame to the Ethernet termination device 550.

  In the alarm reception unit 555 of the Ethernet termination device 550, when the bit of the LINK 420 of the received frame is “1”, the own device is set as the termination point as described above, so the frame transmission unit 551 of the Ethernet termination device 550 Is notified that a link error has been detected.

  The frame transmission unit 551 forcibly disconnects the link with the client device 560 when a link abnormality is notified from the alarm reception unit 555.

1 is a block diagram showing a configuration of a LAN system using an embodiment of a bus LAN termination device according to the present invention. FIG. It is a block diagram which shows the internal structure of the Ethernet termination | terminus apparatus used by embodiment shown in FIG. The Ethernet termination device 210 and the Ethernet termination device 220 have the same configuration. It is a figure which shows the structural example of the special frame produced | generated by the frame production | generation part of the Ethernet termination device shown in FIG. It is a figure which shows the structural example of the encapsulated frame produced | generated by the encapsulation part of the Ethernet termination device shown in FIG. It is a block diagram which shows the connection structural example of the Ethernet termination | terminus apparatus used by embodiment shown in FIG. It is a figure which shows an example of the alarm transmission system in the conventional Ethernet termination device.

Explanation of symbols

110, 160, 230, 240, 530, 560, 630, 640 Client device 120, 130, 140, 150, 210, 220, 510, 520, 540, 550, 610, 620 Ethernet terminator 211, 221 Frame terminator 212 , 222 Special frame termination unit 213, 223 Encapsulation unit 214, 224 Alarm transmission unit 215, 225 Alarm reception unit 216, 226 Decapsulation unit 217, 227 Frame generation unit 218, 228 CPU unit

Claims (8)

  A bus-type LAN termination device comprising setting means for setting whether to be used for relay or termination in a bus-type LAN.   2. The bus-type LAN termination device according to claim 1, further comprising a transmission unit that changes transmission data according to a setting state by the setting unit.   2. The bus-type LAN termination device according to claim 1, further comprising receiving means for changing processing of received data according to a setting state by the setting means. Provided with an alarm receiver for receiving alarms from other bus type LAN termination devices,
When the alarm is received by the alarm receiver in the case where the setting means is set to be used for relay in the bus type LAN and the case is set to be used for termination 4. The bus-type LAN termination device according to claim 3, wherein the processing is different. An alarm receiving unit for receiving information indicating a link error with the client device from a terminal device of another bus type LAN connected to the client device;
When it is set by the setting means to be used for relaying in the bus type LAN, the transmission means transmits information indicating that the link is abnormal and is used for termination in the bus type LAN. 4. The bus LAN termination device according to claim 2, further comprising a link disconnecting unit that disconnects a link with a client device connected as the termination when it is set as a termination. .   The bus-type LAN termination device according to any one of claims 1 to 5, wherein the bus-type LAN is an Ethernet, and the bus-type LAN termination device is an Ethernet termination device.   An alarm transfer method for a terminating device of a bus type LAN, wherein data to be transferred is made different based on whether it is used for relaying or used for terminating in a bus type LAN. In a program of a termination device that operates on a computer for operation as a termination device of a bus type LAN
Computer
A program that functions as a setting means for setting whether to be used for relaying or for termination in a bus type LAN;
A program that functions as an alarm reception unit that receives information indicating a link error with the client device from another bus-type LAN termination device connected to the client device;
When it is set by the setting means to be used for relaying in the bus type LAN, the transmission means transmits information indicating that the link is abnormal and is used for termination in the bus type LAN. And a program for functioning as a link disconnecting means for disconnecting a link with a client device connected as the terminal when it is set as a terminal.

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