JP2011166514A - Packet relay device and fault diagnosis method - Google Patents

Abstract

An object of the present invention is to provide a low-cost packet relay device that guarantees high reliability required for a communication carrier network and at the same time has high functionality.
A packet relay apparatus includes a plurality of interface units for transmitting and receiving data packets, two packet switch units for an active system and a standby system that distribute received data packets to an interface unit corresponding to a destination of the data packet, And a device management unit that transmits and receives control signals to and from an operation device connected to the outside. The interface unit receives a control command from the device management unit, and uses the command to generate a diagnostic packet. Is inserted in a stream of data packets at a predetermined fixed period, and a diagnostic packet sent from another interface unit via the packet switch unit is If the specified number of monitoring cycles do not arrive continuously, Controlling the system switching of Ttosuitchi portion.
[Selection] Figure 2

Description

  The present invention relates to a packet relay device and a failure diagnosis method, and more particularly to a data packet even when a failure occurs in a switch unit that relays an electrical signal from a packet reception interface to a packet transmission interface in a packet relay device constituting a packet communication network. The present invention relates to a packet relay apparatus and a failure diagnosis method that can continue the relay of a packet.

  The recent deregulation of telecommunications has transformed the telecommunications market, previously a government-led oligopoly market, into a competitive society based on capitalism. As a result, competition between conventional communication carriers and emerging communication carriers has intensified, and the reduction in communication charges has been promoted. As a result, there is an urgent need for communication carriers to reduce the operational costs of communication networks (hereinafter sometimes referred to as transmission networks or simply networks) and to switch to more profitable networks. ing.

  With the spread of packet communication technology represented by IP (Internet Protocol) in recent years, IP and Ethernet (registered trademark) technology has been introduced to communication networks for communication carriers, and conventional network synchronous (circuit-switched) communication technology. To the packet-switched communication technology is surely progressing. As a result, most of the traffic becomes packet data, and transmission network construction technology based on circuit switching technology such as SDH (Synchronous Digital Hierarchy) and OTN (Optical Transport Network) is used for data transmission efficiency (traffic for each communication device). In some cases, sufficient investment effects cannot be expected in terms of accommodation efficiency. As a result, the need for packet communication technology that can efficiently accommodate traffic at a lower cost has increased.

  Packet communication technology is a technology that has been widely used for small-scale networks centering on LAN (Local Area Network), and is widely used as a technology for connecting user terminals. It is easy to handle and technical. Has a well-established foundation and can be used for mass production of compatible parts. Therefore, the cost of the packet communication device (hereinafter also referred to as “communication device” or simply “device”) can be reduced as compared with a special communication device for a communication carrier that constitutes a dedicated line. Also, in order to realize a complicated network configuration, development of various control protocols that enable packet communication devices to cooperate with each other and change device settings and path configurations is also progressing. By using these, it is not necessary for the operator to constantly manage the synchronization status between the packet communication devices, and the connection relationship can be established autonomously between the devices. It is easy to replace some communication devices.

  The standardization of Ethernet-related technologies has been carried out by the IEEE (The Institute of Electrical and Electronics Engineers) 802 Committee until around 2002, but since then, the requirements of the communication carriers have been reflected and the ITU-T ( International Telecommunication Union-Telecommunication Standardization Sector (SG) (Study Group) 13 and SG15 have also started. The IEEE 802 Committee and ITU-T SG13 and SG15 are working on standardization in close cooperation, and harmonized standard technologies are defined while complementing each other's discussions. Until now, functions have been expanded mainly in technical fields such as high bit rate communication, large capacity communication, longer communication sections, and improved maintenance operation functions.

  With the standardization of long-distance interface specifications for Ethernet, it is becoming possible to provide high-speed and long-distance transmission equivalent to transmission technologies for communication carrier networks such as SDH and OTN. Realization of an Ethernet transmission network with higher capacity and longer distance than ever is expected.

  Since Ethernet has been developed as a computer-to-computer communication technology for LAN, initially there were almost no regulations regarding OAM (Operation Administration and Maintenance), which is a maintenance management function for a large-scale network constructed by a communication carrier. However, as usage in communication carrier networks has increased, the demand for OAM functions has increased and standardization for Ethernet OAM has been made.

  Further, in applying Ethernet technology to a communication carrier network, improvement of communication reliability (continuity) is one of the issues in addition to maintenance management control using the OAM function. Spanning tree protocols and link aggregation have been used as means for improving reliability, but in addition to these, linear protection switching methods (current transmissions) widely used in conventional SDH and ATM (Asynchronous Transfer Mode). A method of improving fault tolerance by installing a backup transmission path corresponding to the path and switching the communication path to the backup transmission path in the event of a failure in the working transmission path) is ITU-T Recommendation G. It was standardized in June 2006 as 8031 (Non-Patent Document 1).

  In response to the results of standardization activities as described above, it is possible to maintain and manage communication services over the Ethernet network. At present, practical use of the OAM function in a packet communication network including Ethernet has started. Ethernet is usually applied to LANs owned by individual or corporate users, but it can be applied to infrastructure services provided by communication carriers by providing Ethernet technology with a quality management function using OAM. Sex is attracting attention.

  A packet relay device according to the prior art is generally composed of a device management unit, a plurality of interface units, and two packet switch units having a redundant configuration. The two packet switch units have a function of distributing data packets received from any of the plurality of interface units to any of the interface units corresponding to the destinations of the packets. In general, a bus line for control signals is mounted between the device management unit and each module other than the device management unit, and when a failure occurs in one of the two packet switch units, the packet that has failed The switch unit notifies the device management unit of the failure via the bus line. Upon receiving the notification, the device management unit notifies the operation device on the network of the occurrence of the failure. As a result, the operator can know that a failure has occurred in one of the packet switch units of the packet relay apparatus, and can take measures such as replacement work.

  The packet communication device is expected to greatly reduce the cost as compared with a communication device dedicated to a conventional communication carrier network. Recently, there are many examples of reducing the cost of communication equipment by modularizing the functions in the equipment for special communication equipment for communication carriers, and replacing parts that can use general-purpose parts with general-purpose parts. It is done. By modularizing the functions constituting the communication device and increasing the independence between the functions, it becomes easier to handle failures and maintain the communication device. Improvement in maintainability also leads to improvement in the reliability of the communication device. Furthermore, it is possible to reduce the price by configuring each functional module with general-purpose parts capable of mass production. As described above, the common platform construction for designing parts common to devices or systems and similar devices is a method capable of simultaneously realizing high reliability and high functionality of products and cost reduction. For this reason, it has attracted attention in fields other than the communication equipment industry.

ITU-T Recommendation G.8031 / Y.1342

  As described above, a general packet relay apparatus according to the prior art includes an apparatus management unit, a plurality of interface units, and two packet switch units. Since the specifications of the device management unit of such a packet relay device are required to be consistent with the interface specification with the operation device, it is difficult to generalize the interface unit. Therefore, it is difficult for the vendors of each device to make it versatile by original devices.

  However, the packet switch unit only needs to provide connectivity only inside the packet relay device, and as long as the connectivity between the functional blocks (interfaces) can be ensured, it is not affected by the external environment. Can be selected. By paying attention to this point and creating a packet communication device using the packet switch unit as a general-purpose product (or device), the price of the packet communication device can be reduced.

  However, as described above, when a communication failure occurs due to a failure of the packet switch unit or the like, the packet communication device needs means for notifying the operator of the failure. In order to realize this, a packet relay device including a packet switch unit using a general-purpose product needs to add a failure detection function and a notification interface with the device management unit to the packet switch unit.

  In other words, a packet relay device including a packet switch unit using a general-purpose product needs to be modified to a packet switch unit that is a general-purpose product, and as a result, the object of reducing product manufacturing costs can be realized. This causes the problem of being unable to do so. In order to avoid such problems, the packet switch unit interface using a general-purpose product for the packet switch unit detects a failure of the packet switch unit and notifies the device management unit. It suffices to provide means for allocating data packets to the normal one of the active system and the standby system.

  In view of the above-described points, an object of the present invention is to provide a high-performance packet relay device at a low cost while ensuring high reliability required for a communication carrier network, and to configure a functional block of the packet relay device. The packet switch unit is configured with a general-purpose switch, and it is not necessary to modify the general-purpose switch. When a failure occurs in the packet switch unit configured with the general-purpose switch, the failure is detected, and the communication path within the device Is to provide a packet relay apparatus and a fault diagnosis method having a function of notifying an operator of the fault.

  According to the present invention, the object is to provide a packet relay device that constitutes a packet communication network, has a function of transmitting and receiving data packets, and is controllable from an operation device connected to the outside, wherein the packet relay device includes the data packet A plurality of interface units for transmitting and receiving, the two packet switch units for the active system and the standby system for distributing the data packet received from the interface unit to the interface unit corresponding to the destination of the data packet, and the plurality of interface units And a device management unit that transmits and receives control signals to and from the operation device connected to the outside, and the interface unit receives a control command from the device management unit; Generate a diagnostic packet and the packet A diagnostic packet generation / insertion unit that is inserted into the data packet stream to the switch unit, a switching control unit that switches and controls the packet switch unit that is the transmission destination of the data packet, and another interface unit through the packet switch unit. A diagnostic packet termination unit for receiving and terminating the transmitted diagnostic packet; a failure diagnostic unit for determining a path from the diagnostic packet reception state at the diagnostic packet termination unit to the packet switch unit or a failure of the packet switch unit; A failure notification unit that notifies the device management unit of determination information of the failure diagnosis unit; an instruction from the command reception unit; presence / absence of insertion of a diagnostic packet based on the determination information of the failure diagnosis unit; This is achieved by including a diagnostic function management unit that controls system switching of the unit.

  In addition, the object is to provide a failure diagnosis method for a packet relay device that constitutes a packet communication network and has a function of transmitting and receiving data packets, and is controllable from an operation device connected to the outside. A plurality of interface units for transmitting and receiving packets, two packet switch units for the active system and the standby system for distributing the data packet received from the interface unit to the interface unit corresponding to the destination of the data packet, and the plurality of interfaces And a device management unit that transmits and receives control signals to and from the operation device connected to the outside, and the interface unit receives a control command from the device management unit, Will instruct you to insert a diagnostic packet. A diagnostic packet is generated at a predetermined fixed period and inserted into a data packet stream, and the diagnostic packet sent from another interface unit via the packet switch unit is monitored by a predetermined number of times. If the packets do not arrive continuously, this is achieved by controlling system switching of the packet switch unit.

  According to the present invention, it is possible to obtain a packet relay device capable of reducing development costs and providing an inexpensive service to a user, and a failure has occurred in a packet switch unit by a general-purpose switch constituting a redundant system. In this case, the failure can be detected, the route can be switched, and the failure can be notified to the operator.

It is a block diagram which shows the structural example of the general communication network with which this invention is applied, and the structural example of a packet relay apparatus. It is a block diagram which shows the structure of the packet relay apparatus by the 1st Embodiment of this invention. It is a figure explaining the example of a failure generation in the packet relay apparatus by the 1st Embodiment of this invention. It is a figure explaining the apparatus structural example of the interface part in the 1st Embodiment of this invention, and the transmission / reception path | route of a user packet. It is a figure explaining the transmission path | route of the diagnostic packet in the interface part in the 1st Embodiment of this invention. It is a figure explaining the receiving path | route of the diagnostic packet in the interface part in the 1st Embodiment of this invention. It is a flowchart explaining the processing operation in a diagnostic packet termination part. It is a flowchart explaining the processing operation in a failure diagnosis part. It is a flowchart explaining the processing operation in a diagnostic function management part. It is a flowchart explaining the processing operation in a diagnostic packet production | generation insertion part. It is a flowchart explaining the processing operation in a switching control part. It is a block diagram which shows the apparatus structural example of the interface part in the 2nd Embodiment of this invention. It is a figure explaining the method to detect a failure directly in the interface part in the 2nd Embodiment of this invention, and the transfer path | route of the notification information of the detected failure. It is a figure explaining the method to detect a failure indirectly in the interface part in the 2nd Embodiment of this invention, and the transfer path | route of the notification information of the detected failure. It is a flowchart explaining the processing operation in a Link monitoring part. It is a flowchart explaining the processing operation | movement in a failure notification packet termination | terminus part. It is a flowchart explaining the processing operation in a failure diagnosis part. It is a flowchart explaining the processing operation in a diagnostic function management part. It is a flowchart explaining the processing operation | movement in a failure notification packet production | generation insertion part. It is a block diagram which shows the structure of the packet relay apparatus by the 3rd Embodiment of this invention.

  Hereinafter, embodiments of a packet relay device and a failure diagnosis method according to the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a block diagram showing a configuration example of a general communication network to which the present invention is applied and a configuration example of a packet relay device. First, referring to FIG. A configuration example of the packet relay device will be described.

  The general communication network shown in FIG. 1 connects a plurality of networks 1 and 2 accommodating packet communication devices 4 and 5 and packet communication devices 4 and 5 via physical cables 6 and 7 to form a packet. A packet relay device 110 that relays data packets (consisting of a header and a payload) transmitted and received between the communication devices 4 and 5, and an operation device connected to the packet relay device 110 via the network 102 100.

  In the above description, the packet communication device 4 of the network 1 performs communication by transmitting and receiving data packets 8, 9, 10, and 11 with the packet communication device 5 of the network 2 via the packet relay device 110. The packet relay device 110 includes a device management unit 111, a plurality of interface units 121, 122, and 123, and two redundant packet switch units 131 and 132. The interface unit # 1 121, the interface unit # 2 122, and the active packet switch unit 131 are connected by bus lines 141 and 143, respectively. The interface unit # 1 121, the interface unit # 2 122, and the backup packet switch unit 132 are connected to each other. Are connected by bus lines 142 and 144, respectively. The interface unit # 3 123 is also described in the two packet switch units 131 and 132 that are made redundant. The device management unit 111 is connected to the network 102 outside the packet relay device via the control signal route 103 and further connected to the operation device 100 via the control signal route 101. The device management unit 111 communicates with the operation device 100. As indicated by an arrow 151, a user packet is input from a certain interface unit to the packet relay apparatus, and is output from a certain interface unit via the active packet switch unit 131.

  The packet relay device according to the first embodiment of the present invention will be described below. The packet relay apparatus according to the first embodiment of the present invention transmits and receives dedicated diagnostic packets between the interface units, and one interface unit confirms that a diagnostic packet from the other interface unit has arrived. When it is determined that the packet switch unit is normal and the diagnostic packet does not arrive, it is determined that a failure has occurred in the packet switch unit, the system of the packet switch unit is switched, and the diagnosis from the own interface is performed. By stopping packet transmission, the switching of the packet switch unit system is similarly generated for other interface units, and the mismatch of the packet switch unit systems selected between the interface units is prevented. It is a thing.

  FIG. 2 is a block diagram showing the configuration of the packet relay device 110 according to the first embodiment of the present invention.

  As in the case described with reference to FIG. 1, the packet relay apparatus 110 according to the first embodiment of the present invention includes an apparatus management unit 111, a plurality of interface units 121, 122, and 123, and two redundant packet switches. Parts 131 and 132.

  The interface unit # 1 121 includes a packet receiving unit 201 and a packet transmitting unit 202 that are in contact with the outside of the packet relay device, and a packet transmitting unit 211 that is in contact with the inside of the packet relay device and communicates with the active packet switch unit 131. And a packet receiving unit 212, a packet transmitting unit 213 and a packet receiving unit 214 for communicating with the backup packet switch unit 132, and a packet control unit 205. The packet control unit 205 includes a diagnostic function management unit 703 and a fault diagnosis unit 709 as main functions in the embodiment of the present invention. The interface unit # 2 122 is configured similarly to the interface unit # 1 121.

  The active packet switch unit 131 includes a packet reception unit 302 and a packet transmission unit 303 on the interface unit # 1 121 side, a packet reception unit 306 and a packet transmission unit 307 on the interface unit # 2 122 side, and a path determination that is a core function. The unit 301 is configured. The backup packet switch unit 132 is configured in the same manner as the active packet switch unit 131.

  The interface unit # 1 121 and the active packet switch unit 131 are connected by a physical cable 141. Inside the physical cable 141, a packet transmission path 603 from the interface unit # 1 121 to the active packet switch unit 131, A packet transmission path 604 from the active packet switch unit 131 to the interface unit # 1 121 is provided. Other physical cables 142, 143, and 144 also connect the interface unit and the packet switch unit, and are provided with packet transmission paths and packet reception paths 605, 606, 607, 608, 609, and 610, respectively. It has been.

  The packet relay apparatus 110 according to the first embodiment of the present invention uses a dedicated diagnostic packet to monitor a failure of the packet switch unit, but the diagnostic packet is different as indicated by arrows 152 and 153. Data is transmitted and received between the interface units via the active packet switch unit 131 and the standby packet switch unit 132.

  FIG. 3 is a diagram for explaining an example of the occurrence of a failure in the packet relay device 110 according to the first embodiment of the present invention. Here, as an example, it is assumed that a failure 181 has occurred between the interface unit # 1 121 and the active packet switch unit 131.

  In the example shown in FIG. 3, since the interface unit # 1 121 can directly detect a failure, when a failure is detected, the packet switch unit is autonomously used as indicated by an arrow 182 indicated by a dotted line. Switch from primary to standby. At this time, in general, the interface unit # 1 121 notifies the device management unit 111 that a failure has occurred on the active packet switch unit 131, and the device management unit 111 issues a system switching instruction to the interface unit # 2 122. By performing the instruction to be performed, it is possible to continue the conduction of the data packet without the mismatch of the selected packet switch unit system between the interface unit # 1 121 and the interface unit # 2 122. However, at this time, if the device management unit 111 is out of order, or if the device management unit 111 is removed due to replacement work or the like, the selected packet switch system mismatch between the interface units Will occur. When the packet relay device 110 according to the embodiment of the present invention is used for a communication carrier, it is essential to continue the user data even if the device management unit 111 does not function. The present invention prevents the packet switch system mismatch between the interface units even in such a case. Details of the configuration for that purpose will be described later.

  FIG. 4 is a diagram for explaining a device configuration example of an interface unit and user packet transmission / reception paths in the first embodiment of the present invention. In the example shown here, the interface unit # 1 121 is taken as an example.

  The interface unit # 1 121 includes a command reception unit 701 and a failure notification unit 702 in addition to the above-described packet transmission unit, packet reception unit, and packet control unit described with reference to FIGS. The command receiving unit 701 receives a control command from the device management unit 111. On the other hand, the failure notification unit 702 notifies the device management unit 111 of failure information. The packet control unit 205 includes a diagnostic function management unit 703, a diagnostic packet generation insertion unit 704, a switching control unit 705, a packet transmission switching unit 706, a packet reception switching unit 707, a diagnostic packet termination unit 708, and a failure diagnostic unit 709. Has been.

  In the example of the device configuration of the interface unit as described above, the user packet is received by the packet receiving unit 241 in the direction indicated by the arrow 601 and sent to the packet transmission switching unit 706 in the direction indicated by the arrow 203. When the selected packet switch system is the active system, the user packet is sent to the packet transmitting unit 211 and transmitted to the active system packet switch unit in the direction indicated by the arrow 603. When the switch system is the backup system, the packet is sent to the packet transmission unit 213 and transmitted to the backup system packet switch unit in the direction indicated by the arrow 142.

  On the other hand, the user packet sent from the active packet switch unit is received by the packet receiving unit 212, and the user packet sent from the backup packet switch unit is received by the packet receiving unit 214, and each packet reception switching unit 707 is received. Sent to. The packet reception switching unit 707 selects a user packet that has arrived from the selected packet switch unit system, and sends the user packet to the packet transmission unit 242. The user packet is transmitted from the packet transmission unit 242 to an external network and a communication device.

  Although the system selection on the packet transmission side and the reception side is described in the previous paragraph, the system selection may be performed only on the reception side.

  FIG. 5 is a diagram illustrating the transmission path of the diagnostic packet in the interface unit according to the first embodiment of the present invention.

  The maintenance person performs setting for enabling the diagnostic function according to the present invention from the operation device 100 when the system management unit 111 is inserted after the system management unit 111 is replaced after the system is started up. Note that the maintenance person sets the diagnosis function to be invalid at the start of replacement work or the like of the device management unit 111. The setting information is received as a command by the command receiving unit 701 via the device management unit 111 as indicated by a thick line arrow in FIG.

  The command receiving unit 701 sends the command received from the device management unit 111 to the diagnostic function management unit 703. When receiving the diagnostic function valid setting command, the diagnostic function management unit 703 instructs the diagnostic packet generation and insertion unit 704 to generate and insert a diagnostic packet. Upon receiving the instruction, the diagnostic packet generation / insertion unit 704 sends a diagnostic packet to a stream of user packets transmitted to the packet transmission units 211 and 213 corresponding to the packet switch units of both systems at a predetermined period. Insert with and send. Diagnostic packets periodically inserted and transmitted to the packet transmitter 211 are transmitted to the active packet switch unit, and diagnostic packets periodically inserted and transmitted to the packet transmitter 213 are transmitted to the standby packet switch unit Is done.

  FIG. 6 is a diagram illustrating a diagnostic packet reception path in the interface unit according to the first embodiment of the present invention.

  As described with reference to FIG. 5, the diagnostic packet transmitted to the active and standby packet switch units is received by the packet receiving unit 212 and the packet receiving unit 214 of the interface unit # 1 121, and the diagnostic packet termination unit is received. Terminated at 708. The diagnostic packet termination unit 708 monitors the termination status of whether or not diagnostic packets are periodically received, and the diagnostic packet from either the active system or the standby system packet switch unit has a predetermined number of monitoring periods, for example, If the three monitoring cycles have not arrived continuously, the failure diagnosis unit 709 is notified that no diagnostic packet has arrived. Upon receiving this notification, the fault diagnosis unit 709 determines that a fault has occurred in the packet switch unit that has not received the diagnostic packet, and sends it to both the fault notification unit 702 and the diagnostic function management unit 703. To be notified.

  The failure notification unit 702 notifies the device management unit 111 that a failure has occurred between the packet switch unit or the packet switch unit and the interface unit. This notification is sent from the device management unit 111 to the operation device 100. As a result, the operator can take measures for failure recovery. The diagnostic function management unit 703 instructs the switching control unit 705 to switch the system of the packet switch unit when the notified failure is a failure of the path to the active packet switch unit, The diagnostic packet generation / insertion unit 704 is instructed to stop generating and inserting the diagnostic packet. As a result, the diagnostic packet does not arrive at another interface unit connected via the packet switch unit, and the other interface unit can perform system switching of the packet switch unit. If the notified failure is a failure in the path to the standby packet switch unit, the diagnostic function management unit 703 does not perform the above-described processing and performs packet communication using the active packet switch unit. To continue.

  FIG. 7 is a flowchart for explaining the processing operation in the diagnostic packet termination unit 708, which will be described next.

  The diagnostic packet termination unit 708 monitors the arrival of the diagnostic packet from the other interface unit, and determines whether or not the diagnostic packet from any of the active system and the standby system packet switch unit can be confirmed for 3 monitoring periods continuously. (Steps 901 and 902) If the arrival of the diagnostic packet cannot be confirmed for three consecutive monitoring periods, the failure diagnosis unit 709 is notified of the failure of the diagnostic packet (Step 903) and the processing is terminated. .

  FIG. 8 is a flowchart for explaining the processing operation in the fault diagnosis unit 709. Next, this will be explained.

  The failure diagnosis unit 709 waits for reception of the notification that the diagnosis packet has not arrived (steps 911 and 912) from the diagnosis packet termination unit 708, and when the notification that the diagnosis packet has not arrived is received, The failure notification unit is notified of the failure of the corresponding packet switch unit (step 913), and the diagnosis function management unit is similarly notified of the failure of the corresponding packet switch unit (step 914).

  FIG. 9 is a flowchart for explaining the processing operation in the diagnostic function management unit 703, which will be described next.

(1) The diagnostic function management unit 703 monitors reception of a command from the command receiving unit 701, and when receiving a command, determines whether the content of the received command is a diagnostic function valid setting or a diagnostic function invalid setting. (Steps 921, 922, 927).

(2) If it is determined in step 927 that the command content is a valid setting of the diagnostic function, the diagnostic function management unit 703 instructs the diagnostic packet generation / insertion unit 704 to send the diagnostic packet to both packet switch units. The start of generation / insertion is instructed, and the processing here is terminated (step 929).

(3) If it is determined in step 927 that the command content is an invalid setting of the diagnostic function, the diagnostic function management unit 703 instructs the diagnostic packet generation / insertion unit 704 to diagnose the packet switch units of both systems. The stop of packet generation / insertion is instructed, and the processing here is terminated (step 928).

(4) The diagnostic function management unit 703 monitors the reception of the failure notification from the failure diagnosis unit 709 when the command reception is not received in the command reception monitoring from the command reception unit 701 in step 922, and the failure notification is received. If not received, the process returns to the process from step 922 to monitor the command reception (step 923).

(5) When the failure notification is received in the monitoring of the failure notification received from the failure diagnosis unit 709 in step 923, the diagnosis function management unit 703 determines whether the setting state of the diagnosis function is enabled or disabled. If the function is disabled, the process here is terminated without doing anything (step 924).

(6) If it is determined in step 924 that the setting state of the diagnostic function is valid, the diagnostic function management unit 703 sends the diagnostic packet generation / insertion unit 704 to the diagnostic packet generation / insertion unit 704 to insert the diagnostic packet into the faulty system The stop is instructed, and further, the switching control unit 705 is instructed to switch the system of the packet switch unit, and the processing here ends (steps 925 and 926).

  FIG. 10 is a flowchart for explaining the processing operation in the diagnostic packet generation / insertion unit 704, which will be described next.

(1) The diagnostic packet generation / insertion unit 704 waits for reception of an instruction from the diagnostic function management unit 703. When the instruction is received, the instruction content is an instruction to start inserting a diagnostic packet or an instruction to stop inserting a diagnostic packet Is determined (steps 931 to 933).

(2) If it is determined in step 933 that the instruction content from the diagnostic function management unit 703 is the start of insertion of a diagnostic packet, insertion of the diagnostic packet into the specified system (which may be both systems) is started. If the instruction content is an instruction to stop the diagnostic packet, the insertion of the diagnostic packet into the designated system is stopped and the processing here is terminated (steps 935, 934, 936).

  FIG. 11 is a flowchart for explaining the processing operation in the switching control unit 705, which will be described next.

(1) The switching control unit 705 waits for reception of a switching instruction from the diagnostic function management unit 703. When the switching instruction is received, the active system of the packet switch unit is faulty and the standby system is normal. Is determined (steps 941 to 943).

(2) If it is determined in step 943 that the active system of the packet switch unit is out of order and the backup system is in a normal state, the packet transmission switching unit 706 is instructed to switch the transmission destination of the user packet. If the standby system of the packet switch unit is out of order, the process is terminated without issuing a switching instruction (steps 944 and 945).

  This is the end of the description of the first embodiment of the present invention. Next, the second embodiment of the present invention will be described. The second embodiment of the present invention uses a dedicated failure notification packet. For this reason, when the interface unit in the second embodiment of the present invention monitors the link state of the packet transmission path and the reception path in the physical cable connected to the packet switch unit, and detects a link break In addition, a failure notification packet is transmitted from itself to another interface unit. Each interface unit other than the interface that has transmitted the failure notification packet determines that a failure has occurred in the packet switch unit by receiving the failure notification packet, and switches the system of the packet switch unit.

  FIG. 12 is a block diagram showing a device configuration example of the interface unit in the second embodiment of the present invention. In the example shown here, the interface unit # 1 121 is taken as an example.

  The interface unit # 1 121 in the second embodiment shown in FIG. 12 uses a failure notification packet generation / insertion unit 710 instead of the diagnosis packet generation / insertion unit 704 of the interface unit in the first embodiment of the present invention. A failure notification packet termination unit 711 is provided instead of the termination unit 708, and a link monitoring unit 712 is added. As in the case of the interface unit in the first embodiment, the interface unit # 1 121 in the second embodiment of the present invention receives a command from the device management unit 111 by the command receiving unit 701. The diagnostic function is set to be valid / invalid for the diagnostic function management unit.

  FIG. 13 is a diagram for explaining a method of directly detecting a failure in the interface unit and a transfer path of the detected notification information of the failure in the second embodiment of the present invention.

  The link monitoring unit 712 in the interface unit shown in FIG. 13 monitors the state of the link, which is a packet transmission and reception path connected to the packet switch unit, and breaks the link (including failure of the packet switch unit). Is detected, the failure diagnosis unit 709 is notified of the link disconnection. At that time, the failure diagnosis unit 709 notifies both of the failure notification unit 702 and the diagnosis function management unit 703 of the failure of the packet switch unit. Note that a method well known in the art can be used as a method for the Link monitoring unit 712 to monitor the Link state and detect Link disconnection, and a description thereof will be omitted here.

  Upon receiving the failure information, the failure notification unit 702 notifies the device management unit 111 that a failure has occurred between the packet switch unit or the packet switch unit and the interface unit. This notification is sent from the device management unit 111 to the operation device 100, so that the operator can take measures for failure recovery. The diagnostic function management unit 703 instructs the switching control unit 705 to switch the system of the packet switch unit when the notified failure is a failure of the path to the active packet switch unit, and The notification packet generation / insertion unit 710 is instructed to insert a failure notification packet. As a result, another interface unit connected via the packet switch unit can receive the failure notification packet and perform system switching of the packet switch unit. If the notified failure is a failure in the path to the standby packet switch unit, the diagnostic function management unit 703 does not perform the above-described processing and performs packet communication using the active packet switch unit. To continue.

  FIG. 14 is a diagram for explaining a method of indirectly detecting a failure in the interface unit and a transfer path of notification information of the detected failure in the second embodiment of the present invention. The example described with reference to FIG. 14 is an example in another interface unit that has received the failure notification packet transmitted by the interface unit described with reference to FIG.

  14, even when the link monitoring unit 712 of its own interface unit does not detect link disconnection, the failure notification packet from the corresponding packet switch system transmitted by another interface unit detecting link disconnection is transmitted. Will receive. When the failure notification packet termination unit 711 confirms the arrival of the failure notification packet, the failure notification packet termination unit 711 notifies the failure diagnosis unit 709 that the failure notification packet has arrived. Subsequent processing operations in the failure diagnosis unit 709, failure notification unit 702, diagnosis function management unit 703, failure notification packet generation / insertion unit 710, and switching control unit 705 are the same as those described with reference to FIG. .

  FIG. 15 is a flowchart for explaining the processing operation in the Link monitoring unit 712. Next, this will be explained.

  The link monitoring unit 712 monitors the link disconnection with the packet switch unit (step 952), and when detecting the link disconnection with the packet switch unit, notifies the failure diagnosis unit 709 of the link disconnection detection ( Step 953).

  FIG. 16 is a flowchart for explaining the processing operation in the failure notification packet terminating unit 711. Next, this will be explained.

  The failure notification packet termination unit 711 waits for reception of a failure notification packet to be transmitted (step 962). When the failure notification packet is received, the failure notification packet termination unit 711 notifies the failure diagnosis unit 709 that the failure notification packet has been received (step 96). 963).

  FIG. 17 is a flowchart for explaining the processing operation in the fault diagnosis unit 709. Next, this will be explained.

(1) The failure diagnosis unit 709 waits for reception of a link disconnection notification from the link monitoring unit 712 and waits for reception of a failure notification packet from the failure notification packet termination unit 711 (steps 972 and 973).

(2) The failure diagnosis unit 709 waits for reception of the link disconnection notification from the link monitoring unit 712 in step 972 and receives the link disconnection notification from the link monitoring unit 712 or the failure notification packet termination unit 711 in step 973 When a failure notification packet from the failure notification packet termination unit 711 is received while waiting for reception of a failure notification packet from, a failure of the packet switch unit is notified to the diagnostic function management unit 703 and to the failure notification unit 702 Then, the failure of the packet switch unit is notified (steps 974 and 975).

  FIG. 18 is a flowchart for explaining the processing operation in the diagnostic function management unit 703. Next, this will be described.

(1) The diagnostic function management unit 703 determines whether or not a command has been received from the command receiving unit 701. When the command is received, whether the received command content is a diagnostic function valid setting or a diagnostic function invalid setting (Steps 981, 982, and 987).

(2) The diagnostic function management unit 703 performs the diagnostic function valid setting when the command content is the diagnostic function valid setting in the determination of step 987, and the command content is the diagnostic function invalid setting. The diagnostic function is disabled (steps 989 and 988).

(3) If the command is not received in the determination in step 982, the diagnostic function management unit 703 determines whether a failure notification is received from the failure diagnosis unit 709, and the failure notification is not received. In this case, the process returns to the process from step 982 and continues the process (step 983).

(4) If a failure notification is received in the determination in step 983, the diagnostic function management unit 703 determines whether the setting state of the diagnostic function is set valid or invalid, Only when the setting state of the diagnostic function is valid, the failure notification packet generation / insertion unit 710 is instructed to insert a failure notification packet into the failure system, and the switching control unit 705 is instructed to switch the packet switch unit. (Steps 984 to 986).

  FIG. 19 is a flowchart for explaining the processing operation in the failure notification packet generation / insertion unit 710, which will be described next.

  The failure notification packet generation / insertion unit 710 monitors whether a failure notification packet insertion instruction is transmitted from the diagnostic function management unit 703 (step 992), and when there is a failure notification packet insertion instruction, The failure notification packet is inserted into (step 993).

  The first and second embodiments of the present invention described so far have been provided with two packet switch units 131 and 132 made redundant inside the packet relay apparatus 110. The switch units 131 and 132 can also be provided outside the packet relay device 110, and this will be described as a third embodiment of the present invention.

  FIG. 20 is a block diagram showing a configuration of a packet relay apparatus according to the third embodiment of the present invention.

  The packet relay apparatus 110 shown in FIG. 20 is configured such that the packet switch units 131 and 132 in the first and second packet relay apparatuses of the present invention described so far exist outside the packet relay apparatus 110. is there. For this reason, the packet relay device 110 is configured to include switch connection units 171 and 172 in order to connect the packet switch units 131 and 132 existing outside the packet relay device 110 to the packet relay device 110. The operations of the packet relay apparatus 110 and the packet switch units 131 and 132 are the same as those in the first and second embodiments of the present invention connected as described above.

  According to the embodiment of the present invention described above, it is possible to obtain a packet relay device that can reduce development costs and provide inexpensive services to users. The packet relay device according to the embodiment of the present invention detects a failure, switches a route, and notifies the operator of the failure when a failure occurs in the packet switch unit of the general-purpose switch constituting the redundant system. Can do. In addition, the packet relay device according to the embodiment of the present invention includes a mechanism capable of indirectly detecting a failure of the packet switch unit even in an interface unit other than the interface unit that directly detects the failure of the packet switch unit. When switching the route, it is possible to prevent the packet switch units selected to connect between the interface units from being inconsistent.

1, 2, 102 Network 4, 5 Packet communication device 6, 7 Physical cable 8-11 Data packet 100 Operation device 101, 103 Control signal path 104-106, 141-144 Signal line 111 Device management unit 121-123 Interface unit 131 , 132 Packet switch unit 151 Data packet route 154 to 157 User packet route 171, 172 Switch connection unit
201, 211, 213, 303, 307, 403, 407, 501, 511, 513 Packet transmitter
202, 212, 214, 302, 306, 402, 406, 502, 512, 514 Packet reception unit 205, 505 Packet control unit 301, 401 Route determination unit 506, 709 Fault diagnosis unit 515, 703 Diagnostic function management unit 701 Command reception Unit 702 failure notification unit 703 diagnostic function management unit 704 diagnostic packet generation insertion unit 705 switching control unit 706 packet transmission switching unit 707 packet reception switching unit 708 diagnostic packet termination unit 709 fault diagnosis unit 710 fault notification packet generation insertion unit 711 fault notification packet Termination part 712 Link monitoring part

Claims (8)

In a packet relay device that constitutes a packet communication network, has a function of transmitting and receiving data packets, and can be controlled from an externally connected operation device,
The packet relay device is:
A plurality of interface units for transmitting and receiving the data packet;
Two packet switch units of an active system and a standby system that distribute the data packet received from the interface unit to the interface unit corresponding to the destination of the data packet;
A device management unit that controls the plurality of interface units and transmits and receives control signals to and from the operation device connected to the outside.
The interface unit is
A command receiving unit for receiving a control command from the device management unit;
A diagnostic packet generating and inserting unit for generating a diagnostic packet and inserting it into a stream of data packets to the packet switch unit;
A switching control unit that controls switching of the packet switch unit of the transmission destination of the data packet;
A diagnostic packet termination unit for terminating reception of a diagnostic packet sent from another interface unit via the packet switch unit;
A failure diagnostic unit for determining a path from the reception state of the diagnostic packet at the diagnostic packet termination unit to the packet switch unit or a failure of the packet switch unit;
A failure notification unit for notifying the device management unit of determination information of the failure diagnosis unit;
A packet relay comprising: a diagnostic function management unit that controls whether or not a diagnostic packet is inserted and system switching of the packet switch unit based on an instruction from the command receiving unit and determination information in the fault diagnostic unit apparatus. In a packet relay device that constitutes a packet communication network, has a function of transmitting and receiving data packets, and can be controlled from an externally connected operation device,
The packet relay device is:
A plurality of interface units for transmitting and receiving the data packet;
A switch connection unit that secures connection between the active and standby packet switch units that distribute the data packet received from the interface unit to the interface unit corresponding to the destination of the data packet;
A device management unit that controls the plurality of interface units and transmits and receives control signals to and from the operation device connected to the outside.
The interface unit is
A command receiving unit for receiving a control command from the device management unit;
A diagnostic packet generating and inserting unit for generating a diagnostic packet and inserting it into a stream of data packets to the packet switch unit;
A switching control unit that controls switching of the packet switch unit of the transmission destination of the data packet;
A diagnostic packet termination unit for terminating reception of a diagnostic packet sent from another interface unit via the packet switch unit;
A failure diagnostic unit for determining a path from the reception state of the diagnostic packet at the diagnostic packet termination unit to the packet switch unit or a failure of the packet switch unit;
A failure notification unit for notifying the device management unit of determination information of the failure diagnosis unit;
A packet relay comprising: a diagnostic function management unit that controls whether or not a diagnostic packet is inserted and system switching of the packet switch unit based on an instruction from the command receiving unit and determination information in the fault diagnostic unit apparatus.   When the command receiving unit is instructed to insert a diagnostic packet via the diagnostic function management unit, the diagnostic packet generation / insertion unit generates a diagnostic packet at a predetermined fixed period and generates a data packet stream. The diagnostic packet termination unit inserts the fault diagnostic unit when a diagnostic packet sent from another interface unit via the packet switch unit does not arrive continuously for a predetermined number of monitoring cycles. The packet relay apparatus according to claim 1 or 2, wherein a notification that a diagnostic packet has not arrived is sent to the packet relay apparatus. In a packet relay device that constitutes a packet communication network, has a function of transmitting and receiving data packets, and can be controlled from an externally connected operation device,
The packet relay device is:
A plurality of interface units for transmitting and receiving the data packet;
Two packet switch units of an active system and a standby system that distribute the data packet received from the interface unit to the interface unit corresponding to the destination of the data packet;
A device management unit that controls the plurality of interface units and transmits and receives control signals to and from the operation device connected to the outside.
The interface unit is
A command receiving unit for receiving a control command from the device management unit;
A failure notification packet generation and insertion unit that generates a failure notification packet and inserts it into a stream of data packets to the packet switch unit;
A switching control unit that controls switching of the packet switch unit of the transmission destination of the data packet;
Link monitoring unit that monitors the state of Link that is a packet transmission and reception path connected between the packet switch unit,
A failure notification packet termination unit for terminating reception of a failure notification packet sent from another interface unit via the packet switch unit;
A failure diagnosis unit for determining a path from the reception state of the failure notification packet at the failure notification packet termination unit to the packet switch unit or a failure of the packet switch unit;
A failure notification unit for notifying the device management unit of determination information of the failure diagnosis unit;
A packet comprising: a diagnosis function management unit that controls whether or not a failure notification packet is inserted and system switching of the packet switch unit based on an instruction from the command reception unit and determination information in the failure diagnosis unit Relay device. In a packet relay device that constitutes a packet communication network, has a function of transmitting and receiving data packets, and can be controlled from an externally connected operation device,
The packet relay device is:
A plurality of interface units for transmitting and receiving the data packet;
A switch connection unit that secures connection between the active and standby packet switch units that distribute the data packet received from the interface unit to the interface unit corresponding to the destination of the data packet;
A device management unit that controls the plurality of interface units and transmits and receives control signals to and from the operation device connected to the outside.
The interface unit is
A command receiving unit for receiving a control command from the device management unit;
A failure notification packet generation and insertion unit that generates a failure notification packet and inserts it into a stream of data packets to the packet switch unit;
A switching control unit that controls switching of the packet switch unit of the transmission destination of the data packet;
Link monitoring unit that monitors the state of Link that is a packet transmission and reception path connected between the packet switch unit,
A failure notification packet termination unit for terminating reception of a failure notification packet sent from another interface unit via the packet switch unit;
A failure diagnosis unit for determining a path from the reception state of the failure notification packet at the failure notification packet termination unit to the packet switch unit or a failure of the packet switch unit;
A failure notification unit for notifying the device management unit of determination information of the failure diagnosis unit;
A packet comprising: a diagnosis function management unit that controls whether or not a failure notification packet is inserted and system switching of the packet switch unit based on an instruction from the command reception unit and determination information in the failure diagnosis unit Relay device.   The diagnostic function management unit instructs the packet switch unit to switch the system when the Link monitoring unit notifies the link disconnection via the fault diagnostic unit, and also sends a fault notification packet to the fault notification packet generation / insertion unit. The failure notification packet termination unit instructs the system switching of the packet switch unit when the failure notification packet termination unit notifies the failure notification packet via the failure diagnosis unit. 4. The packet relay device according to 4 or 5. In a failure diagnosis method of a packet relay device that constitutes a packet communication network, has a function of transmitting and receiving data packets, and can be controlled from an operation device connected to the outside,
The packet relay device is:
A plurality of interface units for transmitting and receiving the data packet;
Two packet switch units of an active system and a standby system that distribute the data packet received from the interface unit to the interface unit corresponding to the destination of the data packet;
A device management unit that controls the plurality of interface units and transmits and receives control signals to and from the operation device connected to the outside.
The interface unit is
When a control command is received from the device management unit and insertion of a diagnostic packet is instructed by the command, the diagnostic packet is generated at a predetermined period and inserted into a stream of data packets, and other interfaces A packet relay for controlling system switching of the packet switch unit when a diagnostic packet sent from the unit through the packet switch unit does not arrive continuously for a predetermined number of monitoring cycles Device fault diagnosis method. In a failure diagnosis method of a packet relay device that constitutes a packet communication network, has a function of transmitting and receiving data packets, and can be controlled from an operation device connected to the outside,
The packet relay device is:
A plurality of interface units for transmitting and receiving the data packet;
Two packet switch units of an active system and a standby system that distribute the data packet received from the interface unit to the interface unit corresponding to the destination of the data packet;
A device management unit that controls the plurality of interface units and transmits and receives control signals to and from the operation device connected to the outside.
The interface unit is
Monitors the status of the link that is the packet transmission and reception path connected to the packet switch unit and detects link disconnection, and instructs system switching of the packet switch unit and generates a failure notification packet. The packet switch is inserted into the data packet stream, and when a failure notification packet sent from the other interface unit via the packet switch unit is received, the packet switching unit is instructed to switch the system. Fault diagnosis method for relay device.

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