JP6526149B2 - Relay device and its program - Google Patents

Description

  The present invention relates to a relay apparatus and its program, and more particularly, to a relay apparatus and its program for processing communication between a plurality of networks providing communication service according to a predetermined communication protocol.

  A relay apparatus (gateway apparatus (switch)) is widely used as an apparatus that enables communication between a plurality of communication networks, in particular between communication networks based on different protocols, to enable mutual communication.

  In the communication network, various factors may cause a failure that interferes with normal communication, and the relay device has a function to monitor the status of the communication network in order to detect a failure in the communication network promptly. There is a case.

  Also, not only one relay device for connecting a plurality of communication networks but also a plurality of relay devices are prepared, and even if a failure occurs between one relay device and a certain communication network, another relay device is used. It may be designed to allow communication to continue. As described above, when a failure occurs in the communication via the relay device normally used, the communication network can be switched to another communication relay device to realize communication to a desired communication network. Is called a communication network having a bypass function.

  For example, according to the method described in Patent Document 1, when a node detects a failure in the relay network, it blocks the voice line of the extension network. It is also conceivable to secure a bypass communication route by using a plurality of such devices.

Unexamined-Japanese-Patent No. 11-186983

  However, according to the method of Patent Document 1, although the voice line is merely blocked, the processing of actively notifying the occurrence of a fault to the communication network connected to the node is not performed. Absent. Therefore, the communication network may smoothly communicate, such as the possibility of continuing to attempt recommunication on the communication route where the failure has occurred without noticing the occurrence of the failure, or delay of transition to a bypass route for switching to use of another relay device. There are a variety of situations that could interfere with

  SUMMARY OF THE INVENTION In view of such problems, according to the present invention, even when communication between a communication network and another communication network facing each other causes a failure in a communication network to prevent normal communication, the present invention is not limited thereto. A relay apparatus capable of actively and surely notifying occurrence of a failure to a communication network and promoting measures to shift a communication route used in communication between communication networks to a bypass route, and a control method thereof The purpose is to

  In order to solve the problems described above, the present invention provides an interface connected to a network for transmitting and receiving signals to and from another network, another interface connected to another network and transmitting and receiving signals to and from the network, and another interface. Based on a monitoring unit that detects a fault from a network, a learning unit that detects communication of port 80 in TCP (Transmission Control Protocol) from a received signal received from a certain network, and a detection result of the monitoring unit and a detection result of a learning unit And a monitoring unit configured to transmit a predetermined signal to another network constantly or periodically via another interface, and to monitor another signal corresponding to the predetermined signal. The presence or absence of a failure is detected according to the presence or absence of a response from the network, and the learning unit Detecting a communication from a received signal received from the network, there interface takes the configuration of a relay apparatus to the network in a pseudo fault signal.

  Also, the program according to the present invention has one interface connected to a network to transmit and receive signals to and from the other network, and another interface connected to another network to transmit and receive signals to and from the network A relay device interposed between a network and another network is automatically or periodically sent a predetermined signal to another network via another interface, and the presence or absence of a response from the other network to the predetermined signal Correspondingly, monitoring means for detecting the presence or absence of failure, learning means for detecting the communication of port 80 in TCP (Transmission Control Protocol) from a received signal received from a certain network via an interface, detection results of the monitoring means and learning means Control the generation of a false fault signal based on the detection result of Interface a configuration to function as a pseudo fault generating means for transmitting to the network in a pseudo fault signal to.

  In addition, the control method according to the present invention includes an interface connected to a network to transmit and receive signals to and from the network, and another interface connected to another network to transmit and receive signals to and from the network A method of controlling a relay device interposed between a network and another network, wherein the relay device transmits a predetermined signal to another network on its own at all times or periodically via another interface. For detecting the presence or absence of a failure according to the presence or absence of a response from the network, and performing communication to another network where the relay device has detected a failure, the communication of port 80 in TCP (Transmission Control Protocol) If it detects from the received signal received from a certain network, the relay device And it controls the generation of the pseudo fault signal based on the communication, a configuration and a step of transmitting to the network at the interface with a pseudo fault signal.

  Further, another relay device according to the present invention is connected between a certain network and another network which is interposed between a certain network and another network and which transmits and receives a signal to and from another network. And another interface for transmitting and receiving a signal, and further transmitting a predetermined signal to another network at all times or periodically via another interface, and the presence or absence of a response from the other network to the predetermined signal. In accordance with the monitoring unit that detects the presence or absence of a failure, communication of port 80 in the communication protocol TCP (Transmission Control Protocol) from a relay signal received from a certain network via an certain interface from one network to another network Detecting learning unit, detection result of monitoring unit and detection of learning unit Result and a pseudo-fault failure status data generated by the pseudo-fault generation unit that generates an HTTP (HyperText Transfer Protocol) pseudo-fault condition in the relay apparatus and an HTTP pseudo-fault condition generated by the pseudo-fault generation unit And a storage unit for storing at least another HTTP pseudo failure status data different from the failure status data, wherein the pseudo failure creation unit generates an HTTP pseudo failure based on a certain HTTP pseudo failure status data or another HTTP pseudo failure status data. When an HTTP pseudo-fault status is generated based on certain HTTP pseudo-fault status data, an interface of the relay apparatus performs processing for returning an HTTP pseudo-fault signal including a predetermined HTTP status code to a network. When creating an HTTP pseudo failure state based on another HTTP pseudo failure state data, what process is the process of returning an interface of a relay device being? It is configured to the composed process.

  According to the present invention, when a relay device intervening between one network and another network detects communication from a received signal received from another network after detecting a failure from the one network, a pseudo failure signal is generated. As a result, it is possible to positively and surely notify the occurrence of a failure to a network other than the network where the occurrence of the failure is detected. Further, it is possible to urge a measure to shift the communication route to the bypass route when performing communication between networks.

It is a block diagram showing composition of an example of a gateway device concerning the present invention. It is a block diagram which shows roughly the example of construction | assembly of the network using the gateway apparatus shown in FIG. It is a figure which shows an example of the pseudo | simulation failure state data memorize | stored in the memory | storage part shown in FIG. It is a block diagram which shows the example of an internal structure of the control part shown in FIG. It is a flowchart which shows the production | generation operation | movement of the pseudo | simulation failure state which the gateway apparatus shown in FIG. 1 performs, and the processing operation of the communication network resulting from the operation | movement. It is a figure which shows the production | generation operation | movement of the pseudo | simulation failure state which the gateway apparatus shown in FIG. 1 performs, and the processing operation of the communication network resulting from the operation | movement. In the embodiment shown in FIG. 1, it is a flow chart showing recovery operation from a simulated fault condition. It is a sequence chart which shows the operation | movement in the case of producing | generating a pseudo | simulation failure state using the pseudo | simulation failure state data shown in FIG. It is a block diagram which shows the structure of another Example of the gateway apparatus based on this invention. It is a block diagram which shows the internal structural example of the learning part shown in FIG. It is a figure which shows an example of the pseudo | simulation failure state data memorize | stored in the memory | storage part shown in FIG. 10 is a flowchart showing an operation of analyzing a fault detection method of the communication network in the gateway device shown in FIG. 9;

  An embodiment of a gateway device according to the invention will now be described in detail with reference to the accompanying drawings. Referring to FIG. 1, an embodiment of the gateway apparatus 10 (GW) according to the present invention is configured to execute communication between a plurality of communication networks providing communication services according to a predetermined communication protocol (communication protocol), as needed. The control unit 12 performs overall control of the gateway device 10 such as conversion of a communication protocol while interlocking with respective units of the device 10 described later.

  Also, the gateway device 10 receives a signal including data information and the like between the device 10 and the communication network, which is arbitrarily connected so as to be able to receive a control signal required from the control unit 12 to execute communication between communication networks. It has ports 14a-14c which are interfaces for output. The detailed connection mode of the control unit 12 and the port 14 will be described later together with the connection mode of each unit in the control unit 12 and the apparatus 10.

  Furthermore, the ports 14a to 14c are connected to the communication networks 20a to 20c via arbitrary communication lines such as communication lines 16a to 16c using serial or parallel transmission methods. Although three communication networks 20 and three ports 14 are shown in the figure, this is merely a matter of convenience for explanation, and the number of communication networks 20 connected with the gateway device 10 and the number of ports 14 required therefor are as follows. Is optional.

  With such a configuration, the gateway device 10 receives information from the communication network (for example, the communication network 20a) to which the transmission source of communication information belongs, performs necessary protocol conversion by the operation of the control unit 12 or the like, and the communication network to which the transmission destination belongs. By passing information to (for example, the communication network 20b), communication between different communication networks is established.

  A network constructed by connecting the communication networks 20a to 20c with the gateway device 10 is shown in FIG. Here, the communication networks 20a to 20c are communication networks having a predetermined communication protocol for each arbitrary communication network such as Integrated Services Digital Network (ISDN), Ethernet, Fiber Distributed Data Interface (FDDI), and token ring. That is, the present invention can be used in connection with a communication network having any known communication protocol.

  The communication networks 20a to 20c are mutually connected via a plurality of gateway devices 10a and 10b. Here, the gateway device used for inter-network communication in normal times is assumed to be the device 10a, and on the other hand, information is exchanged instead of the device 10a when some trouble occurs in the route passing through the device 10a and smooth communication can not be performed. A standby gateway apparatus that executes transmission / reception, protocol conversion, etc. is referred to as the apparatus 10 b. The communication networks 20a to 20c are connected to the standby system 10b using communication lines 16d to 16f as well as connected to the gateway 10a using the communication lines 16a to 16c.

  Further, the communication networks 20a to 20c respectively have terminals 24a to 24c connected via the lines 22a to 22c and used for operations for the user to transmit and receive communication data. With such a network configuration, for example, when the user of the terminal 24a intends to communicate with the user of the terminal 24b, the data inputted from the terminal 24a is normally transmitted through the line 22a, the communication network 20a and the communication line 16a to the gateway device The data is supplied to 10a, and the necessary protocol conversion is performed in the apparatus 10a, and the converted data is transmitted to the terminal 24b via the communication line 16b, the communication network 20b and the line 22b.

  Further, in the communication networks 20a to 20c constituting the present network, a fault occurs in the gateway device 10a by the detection units 26a to 26c and the detection units 26a to 26c that detect occurrence of a failure in the gateway device 10a being used for inter-network communication. When it detects, it shall have switching parts 28a-28c switched to the communication route which goes through via the gateway apparatus 10b provided preliminarily. That is, communication networks 20a to 20c constituting the present network are assumed to be communication networks having a so-called bypass function.

  In the description of this embodiment, the communication networks connected to the gateway devices 10a and 10b are three communication networks 20a to 20c for convenience of explanation, but the number of communication networks 20 connected to the gateway device 10 is of course arbitrary It is.

  With such a network configuration, for example, assuming that the device 10a is normally used for communication from the communication network 20a to the communication network 20b, the communication network 20a does not receive the device 10b even if a failure occurs between the device 10a and the communication network 20b. Communication to the communication network 22b can be performed via the communication network 22b.

  Returning to FIG. 1, the other components of the gateway device 10 will be described in more detail. In the present embodiment, as shown in FIG. 1, transmission and reception of data and signals between components in the apparatus 10 and the outside of the apparatus 10 are provided in the apparatus 10 and serve as a communication bus 30 serving as a path of data and signals. It is supposed to be done through. For example, the control unit 12 is connected to the communication bus 30 via the signal line 32, and the communication bus 30 is further connected to the ports 14a to 14c via the signal lines 34a to 34c. By providing the communication bus 30 in this manner, transmission or reception of control signals from the control unit 12 to the ports 14a to 14c, and signals between components in the apparatus 10 such as the control unit 12 and units to be described later. And sending and receiving of data. However, this connection mode in which the communication bus 30 is installed is merely wired as an example for the sake of convenience so as to simply explain the present invention, and various conditions such as signal processing efficiency and manufacturing cost are taken into consideration. The optimal connection configuration may be adopted as appropriate.

  The gateway device 10 is connected to the ports 14 a to 14 c and the control unit 12 via the signal line 38 and the communication bus 30, and constantly or periodically states of the communication networks 20 a to 20 c according to a monitoring instruction from the control unit 12. The monitoring unit 40 monitors the The monitoring unit 40 is based on the information received from the communication networks 20a to 20c via the ports 14a to 14c, or the failure of the communication networks 20a to 20c by an appropriate method such as the presence or absence of a response from the communication network side to the signal transmitted by itself. When it is determined that any of the communication networks 20a to 20c is in a failure state, a failure detection signal is transmitted to the control unit 12.

  Also, the gateway device 10 is connected to the ports 14 a to 14 c and the control unit 12 via the signal line 44 and the communication bus 30, and the occurrence of a failure is detected between the device 10 and any communication network 20 by the monitoring unit 40. In this case, a pseudo failure generation unit that generates a pseudo failure in the ports 14a to 14c connected to the communication network facing the communication network 20 in which the failure occurrence is detected in response to the reception of the command signal from the control unit 12 It has 46.

  That is, for example, when occurrence of a failure is detected on the communication network 20b side as viewed from the gateway device 10, a pseudo failure is generated in the ports 14a and 14c connected to the communication networks 20a and 20c facing the communication network 20b. . In addition, when the monitoring unit 40 that detects a failure in the communication networks 20a to 20c subsequently detects the disappearance of the failure, the pseudo failure generation unit 46 causes the ports 14a to 14c to generate in response to an instruction from the control unit 12. It is also possible to eliminate false failures.

  Furthermore, the gateway device 10 is connected to each unit such as the control unit 12, the monitoring unit 40, and the simulated fault generation unit 46 via the signal line 48 and the communication bus 30, and a protocol stack or the like for realizing communication is implemented. A storage unit 50 is provided. Furthermore, the storage unit 50 holds simulated failure status data 52 set as to what port is used to generate what type of simulated failure. In addition, the storage unit 50 can store the state of the gateway device 10 at that time, such as the presence or absence of the pseudo failure state, by receiving the storage instruction signal from the control unit 12.

  FIG. 3 shows an example of the simulated fault state data 52 set and held in the storage unit 50. As shown in FIG. As the simulated fault state data 52, various types of data D1 to D4 are stored, including, for example, data such as the route 54, the communication layer 56, the simulated fault processing 58, and the fault detection 60 of the opposing apparatus.

  In the route 54, ports 14a to 14c connected to the communication lines 16a to 16c and performing signal input / output with the communication networks 20a to 20c are shown.

  The communication layer 56 indicates seven communication function layers defined by the OSI Reference Model (Open Systems Interconnection Reference Model). For example, when the port 14a is connected to the ISDN communication network, the communication function of layer 1 (physical layer) may be a bit-stream transmission function or synchronization function by Bch (B channel) or Dch (D channel). Although only the layer 2 (data link layer), the layer 3 (network layer) and the layer 7 (application layer) other than the layer 1 are shown in the communication layer 56 in the figure, this is merely an example, It does not prevent the layers not listed in the figure from being stored as the contents of the communication layer 56.

  The simulated fault processing 58 in the simulated fault state data 52 is a simulated fault state in which the simulated fault generation unit 46 specifically generates a port connected to the communication network facing the communication network in which the fault has occurred. It is processing content. For example, when the port 14a is connected to the ISDN communication network, the pseudo failure generation unit 46 performs processing to delay transmission of the transmission frame to the port 14a, whereby the failure of the synchronization failure with respect to the detection unit 26a of the communication network 20a. To identify that has occurred. The simulated fault processing 58 stored in the storage unit 50 as part of the data 52 is a device 10 for any communication network that can be connected to the device 10 according to the present embodiment, such as an ISDN network or an Ethernet network. It is possible to set a simulated fault that causes a fault to be recognized as having occurred.

  With the fault detection 60 of the opposing apparatus, any pseudo fault processing 58 stored in the storage unit 50 by the pseudo fault generation unit 46 of the device 10 is performed, and the communication network that makes the pseudo abnormal state 58 confront the gateway device 10 This refers to a specific failure state that the communication network 20 identifies when the twenty detection units 26 detect.

  Therefore, based on the simulated fault state data 52 held in the storage unit 50, the control unit 12 sends, for example, the route 54 "port 14a", the communication layer 56 "layer 1", and the simulated fault processing 58 "send frame delay transmission When the simulated failure generation unit 46 is instructed to execute setting of the data type D1 with “fault out” with the failure detection 60 of the opposing device, the simulated failure generation unit 46 executes such a command to execute By performing processing to delay transmission of the transmission frame in layer 1, the communication network 20a connected to the port 14a is made to identify the failure state of “out of synchronization”.

  Of course, the simulated fault processing 58 shown in FIG. 3 is an example, and the simulated fault processing 58 corresponding to the communication protocol of the communication layer 56 can be set as appropriate.

  According to FIG. 3, a plurality of pseudo failure processes 58 are prepared for one port. By this, it is possible to change the generated simulated fault processing 58 every predetermined time. As a result, even if the communication network 20 connected to the gateway device 10 is a communication network having a function of automatically recovering from, for example, an out-of-synchronization state, such as sending no B & D ch frame to the device 10 after a predetermined time. Since another simulated fault process 58 is performed, the probability that the communication network 20 is identified as having a fault in the device 10 can be increased.

  As described above, the control unit 12 performs overall control of the gateway device 10, but in order to help the understanding of the present invention, various functions provided in the control unit 12 will be described here. Several elements to realize are described with reference to FIG.

  The control unit 12 is configured to change the simulated failure process 58 to be generated on the port 14 at predetermined time intervals, such as every 5 seconds, when the plurality of simulated failure status data 52 is stored in the storage unit 50. You may have the change part 62 which controls the production | generation part 46. FIG.

  In addition, the control unit 12 is pseudo-generated on the port 14 by execution of the simulated failure processing 58 when it is further detected that the failure detected in any of the communication networks 20 by the monitoring unit 40 is subsequently eliminated. You may have the restoration part 64 which controls the pseudo | simulation failure generation part 46 used to eliminate a failure.

  Furthermore, the control unit 12 refers to the monitoring cycle of the monitoring unit 40 to determine the time interval at which the presence or absence of a fault is detected, and the number of times abnormal data is detected continuously or in total as a fault. You may have the adjustment part 66 which adjusts the frequency | count of detection of the monitoring part 40, etc. FIG. By providing the adjustment unit 66 and adjusting the monitoring conditions according to possible abnormalities, it is immediately judged that there is a slight abnormality that does not affect the continuation of communication or an abnormality that can be recovered instantaneously as a communication failure. It can prevent being done.

  In the present embodiment, the control unit 12 provided in the gateway device 10, the monitoring unit 40 monitoring the communication network 20 under control of the control unit 12, and a simulated failure generation unit generating a simulated failure state 46 are separately shown in order to clarify the operation of the components provided in the apparatus 10. However, some or all of these components may be integrated as hardware or software. For example, the control unit 12 may be integrally configured to also serve as the monitoring unit 40 and the simulated failure generation unit 46.

  Similarly, for the changing unit 62, the recovery unit 64 and the adjustment unit 66 described as internal elements of the control unit 12 in the present embodiment, for example, the change unit 62 and the recovery unit 64 are provided as internal elements of the simulated failure generation unit 46 Of course, any configuration can be adopted in the gateway device 10.

  Subsequently, referring to FIG. 5 and FIG. 6, it corresponds to the basic operation of the device 10 and the operation of the device 10 when a communication failure occurs in any of the communication networks 20 connected to the gateway device 10. The operation of the communication network 20 will be described.

  When the gateway device 10 processed for normal communication between the communication networks 20a and 20b is the device 10a, the monitoring unit 40 of the device 10a monitors the state of the communication networks 20a and 20b connected to the device 10a. doing. Therefore, for example, when a failure that prevents normal communication occurs between the device 10a and the communication network 20b, the gateway device 10a recognizes the occurrence of the failure through the detection of the failure occurrence by the monitoring unit 40 (step S10).

  When occurrence of a failure on the communication network 20b side is detected from the gateway device 10a, the control unit 12 of the device 10a sends a command to the simulated failure generation unit 46, and the simulated failure state held in the storage unit 50 Based on the data 52, the port 14a connected to the communication network 20a facing the communication network 20b in which the failure has occurred is shifted to the pseudo failure state (step S20).

  The simulated fault condition to be specifically generated is selected from the data types D1 to D4 of the simulated fault condition data 52 according to the communication protocol of the communication network connected to each port. For example, when the communication network 20a is an ISDN network, the pseudo failure of the port 14a generated by the pseudo failure generation unit 46 according to an instruction of the control unit 12 is layer 1 transmission frame delay transmission of data type D1, for example. .

  Further, the gateway device 10 controls the storage unit 50 from the control unit 12 to store information indicating that the device 10 itself is in a simulated failure state. (Step S30)

  The communication network 20a connected to the port 14a in which the simulated failure is generated detects that a failure has occurred in the gateway 10 by the detection unit 26a (step S40). The communication network 20a that detects the occurrence of a failure in the gateway device 10 passes through the standby gateway device 10b in place of the device 10a that has been used for inter-network communication by the switching unit 28a. The setting is switched so that communication with the communication network 20b can be performed by the route (step S50). As a result, normal communication between the communication networks 20a and 20b is restored.

  As described above, the gateway device 10 automatically shifts the port 14a connected to the opposite communication network 20a to the simulated failure state in response to the failure detection of the one communication network 20b, thereby causing the other communication network 20a to operate. It becomes possible to actively promote bypass communication.

  In this description, the operation of the gateway device 10 for securing normal communication between the communication networks 20a and 20b when a failure occurs in the communication network 20b has been described as an example. However, of course, the operation performed by the device 10 on the port 14c connected to the communication network 20c in order to secure the normal communication of the communication between the communication networks 20c and 20b is also the same. Therefore, the users of the terminals 24a to 24c installed in the respective communication networks 20a to 20c use the other terminal 24 in the same manner as when no failure occurs even if a failure occurs in any of the communication networks 20. It is possible to communicate with the

  By the same principle, when a bypass route via the gateway device 10b is selected due to the occurrence of a failure on the communication network 20b side, the failure on the communication network 20b side is solved thereafter, and the monitoring unit 40 of the device 10a fails When it is detected that the above is detected, it is also possible to prompt the communication network 20a or 20c opposite to the communication network 20b to promptly restore the route between the communication networks to the normal route by the command of the recovery unit 64.

  An example of the basic operation of the device 10 and the operation of the communication network 20 with respect to the operation of the device 10 for prompting recovery from the bypass route to the normal route will be described using FIG. 7.

  The gateway device 10a used for relaying communication between communication networks at normal time is a monitoring unit even when transmission and reception of communication information and the function as a protocol conversion device are suspended due to the occurrence of a failure on the communication network 20b side as viewed from the device 10a. Monitoring of the fault condition on the communication network 20b side is continued by 40. FIG. As a result, when the fault occurring between the device 10a and the communication network 20b is eventually eliminated, the fact of the fault elimination can be detected (step S60).

  The monitoring unit 40 notifies the control unit 12 that the failure has been eliminated when it detects that the failure state occurring on the communication network 20 b has been eliminated. The recovery unit 64 in the control unit 12 that has received this notification instructs the simulated failure generation unit 46 to end the generation of the simulated failure state. In response to this instruction, the simulated fault generation unit 46 restores the status of the simulated fault processing 58 created in the ports 14a and 14c to the normal status (step S70). The gateway device 10 controls the storage unit 50 from the control unit 12 to store the state of the restored device 10 so as to store information indicating that the device 10 has recovered from the simulated failure state. (Step S80)

  The communication network 20a connected to the port 14a recovered from the pseudo failure detects that the failure status of the gateway device 10 has been recovered by the detection unit 26a (step S90), and the switching unit 28a causes the failure to occur. The setting is returned to execute communication with the communication network 20b using the gateway device 10a, which is a route normally used, in place of the device 10b used for inter-network communication (step S100).

  As described above, by providing the gateway 10 with a configuration for prompting restoration of the communication route between the communication networks to the normal route when the fault condition of one communication network is eliminated, it is used for inter-network communication. In any of the switching of the gateway device 10 and the recovery thereof, network processing can be smoothly performed without adversely affecting the user of the terminal 24.

  By the way, some communication networks 20 have a failure recovery function that automatically attempts to overcome communication and continue communication when it detects that a failure has occurred in the connecting gateway device 10. There is a case. In that case, even if a simulated failure is created in the gateway device 10, the failure recovery function of the communication network 20 works and the internetwork communication is continued without switching to the bypass route. However, since the failure existing between the gateway 10 and the other communication network has not recovered, normal communication is still impossible.

  In order to prevent such a situation and to increase the probability that the communication network in use is identified to be in a failure state by the communication network on the other side from the side where the failure has occurred, the storage unit 50 has one port The plurality of simulated fault processes 58 and the change unit 62 for controlling changes in the simulated fault state are prepared, and it is possible to adopt a configuration in which the simulated fault process 58 can be changed at predetermined time intervals. That's right. Here, the operation of the gateway 10 will be described in the case where the configuration capable of generating different simulated failure states according to time is taken.

  In the network of FIG. 2 in the present description, the communication network 20a is an ISDN network, and the communication network 20c is Ethernet. The port 14a connected to the ISDN communication network 20a is an ISDN-compatible port, and the port 14c connected to the Ethernet communication network 20c is a LAN (Local Area Network) standard IEEE 802.3 (the Institute of Electrical and Electronic Engineers 802.3). ) It shall be a corresponding port. Of course, this setting condition is only an aspect of the embodiment, and the gateway device 10 may be connected to a communication network of any communication protocol.

  In the case where the gateway device 10 generates different simulated fault conditions every time, operations corresponding to step S20 and step S30 among the operations of the device 10a shown in FIG. 5 and FIG. 6 are repeated a plurality of times. . A description of the operation taken by the gateway device 10a in this case will be described with reference to the attached FIG.

  The gateway device 10a connected to the communication networks 20a to 20c and executing transmission / reception of information and protocol conversion monitors the monitoring unit 40 for the occurrence of communication failure in each communication network 20. For example, when a failure that prevents normal communication is detected from the communication network 20b side (step S110), the monitoring unit 40 transmits a detection signal to the control unit 12 to notify the occurrence of a failure (step S120).

  The control unit 12 that has identified the occurrence of a communication failure in the communication network 20b refers to the simulated failure state data 52 held by the storage unit 50 as processing for automatically shifting the gateway 10a to the simulated failure state (step S130). ), For example, a command is sent to the simulated fault generation unit 46 to realize the setting of the data type D1 described in the top row (step S140). The simulated fault generation unit 46 that has received the command performs processing to generate a simulated state of the data type D1 (step S150). Specifically, the pseudo failure generation unit 46 causes frame transmission to be performed at an interval exceeding the transmission timing defined by the protocol stack implemented in the storage unit or the like in the layer 1 of the port 14a. For example, in the case of a one second interval in the protocol stack, it transmits at an interval exceeding one second, such as 1.3 seconds. Further, when the communication timing is synchronized between the gateway device 10a and the communication network 20a, frames are sent out at a timing that deviates from the synchronization intentionally. In this way, the communication network 20a, which is the opposite device, is made to identify the failure state of "out of synchronization".

  After the simulated fault state set to the data type D1 is executed in the gateway device 10a, the control unit 12 stores in the storage unit 50 information indicating that the device 10 itself is in the simulated fault state of the data type D1. Control is performed (step S160).

  Thereafter, after a predetermined time such as 5 seconds has elapsed, for example, the control unit 12 including the changing unit 62 starts control for changing the simulated failure process 58 generated in the port 14a. First, the control unit 12 refers to the simulated fault state data 52 stored in the storage unit 50 (step S170), and this time, the simulated fault generation unit 46 realizes the setting of the data type D2 as the next data related to the port 14a. Command (step S180). The simulated fault generation unit 46 that has received the instruction performs processing to generate a simulated state of the data type D2 (step S190). Specifically, the pseudo failure generation unit 46 performs a process of not transmitting the B & Dch frame in the layer 2 of the port 14a. Here, when not transmitting the B & Dch frame, the control unit 12 controls each unit so as not to transmit the call control message or the packet information based on the call control message defined by the protocol stack implemented in the gateway device 10. Do. In this manner, the communication network 20a, which is the opposite device, identifies the failure state of "communication failure".

  After the simulated fault state set to the data type D2 is executed in the gateway device 10a, the control unit 12 stores in the storage unit 50 information indicating that the device 10 itself is in the simulated fault state of the data type D2. Control is performed (step S200).

  Thereafter, after a predetermined time such as 5 seconds has elapsed, for example, the control unit 12 refers again to the simulated failure state data 52 stored in the storage unit 50 (step S210). Since all the next data related to the port 14a has been executed, the control unit 12 including the change unit 62 subsequently sends a command to the simulated failure generation unit 46 to realize the setting of the data type D3 which is data related to the port 14c. (Step S220). The simulated fault generation unit 46 that has received the command performs processing to generate a simulated state of the data type D3 (step S230). Specifically, the pseudo failure generation unit 46 performs a process of not transmitting an ICMP control (Internet Control Message Protocol Reply) at layer 3 of the port 14c. Here, when the ICMP Reply is not transmitted, the control unit 12 performs a process of not transmitting the ICMP Reply based on the ICMP message defined by the protocol stack implemented in the gateway device 10. Therefore, even if the gateway device 10 receives a ping (Echo Request) from the communication network 20c, the device 10 does not return a ping response. In this way, the communication network 20c, which is the opposite device, is made to identify the failure state of "Heartbeat".

  After the simulated failure process 58 set to the data type D3 is executed in the gateway device 10a, the control unit 12 stores the information indicating that the device 10 itself is in the simulated failure state of the data type D3 in the storage unit 50. Control to be stored is performed (step S240).

  Thereafter, after a predetermined time such as 5 seconds has elapsed, the control unit 12 including the change unit 62 refers again to the simulated failure state data 52 held in the storage unit 50 (step S250), and this time the next related to the port 14c The command is sent to the simulated fault generation unit 46 to realize the setting of the data type D4 as the data of (step S260). The simulated fault generation unit 46 that has received the command performs processing to generate a simulated state of the data type D4 (step S270). Specifically, the simulated failure generation unit 46 performs a process of not transmitting a Simple Network Management Program Trap (SNMP Trap) in the layer 7 of the port 14c. Here, when the SNMP Trap is not transmitted, the control unit 12 performs a process of not transmitting the SNMP Trap based on the SNMP message defined by the protocol stack implemented in the gateway device 10. Therefore, the gateway device 10 suspends the transmission of the SNMP Trap which is regularly transmitted to the communication network 20c. In this way, the communication network 20c, which is the opposite device, is made to identify the failure state of "monitoring failure".

  After the simulated failure processing 58 set to the data type D4 is executed in the gateway device 10a, the control unit 12 stores the information indicating that the device 10 itself is in the simulated failure state of the data type D4 in the storage unit 50. Control to be stored is performed (step S280).

  As described above, the gateway device 10 changes the content of the simulated fault generated in the device at predetermined time intervals, so that the communication network 20 connected to the device 10 has a fault recovery function even if it is connected. Even if this is the case, it is possible to increase the probability of causing the communication network 20 to identify the occurrence of a failure based on the simulated failure state of the device 10. As a result, switching to the bypass communication route can be urged more quickly.

  The order of selection of the pseudo fault condition data 52 actually generated is arbitrary. In addition to creating a simulated fault state sequentially for each port, processing may be performed to create a simulated fault state simultaneously for a plurality of ports.

  Although the communication network in which the failure first occurred is the communication network 20b connected to the port 14b in the above description according to the embodiment of the present invention, which communication network is the communication network in which the failure occurred Even if this is the case, of course, the gateway apparatus 10 can cause the opposing communication network group to identify the occurrence of the pseudo failure by taking the above operation to the other port.

  Next, another embodiment of the gateway device 10 according to the present invention will be described. For example, in the case where a new communication network 20d is connected to the gateway device 10 in operation, for example, in the gateway device 10 according to this embodiment, what method is used by the communication network 20d to detect a failure occurrence of the device 10? It is possible to analyze

  The configuration of the gateway device 10 according to the embodiment to be described this time is as shown in FIG. The same parts as the constituent elements of the previous embodiment are represented using the same reference numerals. The gateway device 10 according to the present invention is assumed to have ports 14a to 14d, and a new communication network 20d is connected to the port 14d.

  Similar to the communication networks 20a to 20d shown in FIG. 2, the communication network 20d includes a detection unit 26d for detecting the occurrence of a failure in the gateway 10 and a switching unit 28d for switching the communication route. However, at the stage of the new connection, it is assumed that the gateway device 10 does not recognize what failure detection means or method is the detection unit 26 d.

  The gateway device 10 according to the present embodiment has a learning unit 70 connected to the communication bus 30 via the signal line 68. The learning unit 70 detects periodic communication in communication per predetermined unit time from each communication network 20 under the control of the control unit 12, and translates the communication protocol using the protocol stack, Are stored in the storage unit 50. Furthermore, the learning unit 70 performs detection, collation and storage processing of periodic communication for each unit time any number of times, and compares the storage history of each time to the communication network 20 d for the newly connected gateway device 10. Is an apparatus to infer and analyze the fault detection method adopted by

  The unit time at the time of detection may be any time, for example, 10 minutes from the start of the gateway device 10. Here, when the starting point of the unit time is the activation time point of the device 10, the control unit 12 performs control so as to, for example, once restart the gateway device 10 each time the periodic communication detection starts.

  More specifically, an example of the configuration of the learning unit 70 will be described with reference to FIG. First, the learning unit 70 may have a periodic signal detection unit 72 that monitors a signal transmitted from the communication network 20 d newly connected to the port 14 d and detects a signal received periodically. The learning unit 70 can also have a translating unit 74 that translates a communication protocol based on the protocol stack stored in the storage unit 50 for the periodic signal detected by the periodic signal detecting unit 72. Furthermore, the learning unit 70 compares the translation results for a predetermined number of times stored in the storage unit 50, and an analysis unit 76 that estimates and analyzes the fault detection method implemented by the communication network 20d by means such as deriving common points. May be included.

  For example, in the storage history of each time, when the detection result and the translation result that the ping is periodically transmitted to the gateway device 10 from the newly connected communication network 20d are stored in the storage unit 50, the ping is a layer Since the communication check is performed using the ICMP specified in the protocol located at 3, the analysis unit 76 analyzes that the specific abnormality detection method adopted by the communication network 20d is the communication check by ping.

  In addition, the storage unit 50 stores the detection and translation result that a session by a predetermined port such as TCP 80 (Transmission Control Protocol 80) is reestablished from the communication network 20 d each time the device 10 is restarted. In this case, the learning unit 70 determines that the continuous session maintenance during the detection period is a kind of periodic communication, and the detection method adopted by the communication network 20 d detects an abnormality of the device 10 by disconnection of the TCP session. Analyze it as

  The storage unit 50 sets and holds simulated fault state data 152, an example of which is shown in FIG. As the simulated fault state data 152, various types of data D5 to D10 including data such as the communication layer 56, the simulated fault process 58, and the fault detection 60 of the opposing apparatus are stored. In the simulated fault state data 152 of the present embodiment, as the simulated fault processing 58, in addition to the ICMP non-transmission (data D5) stored also as the simulated fault state of the previous embodiment, RIP (Routing Information Protocol) ) Response Not sent, TCP DIN (Transmission Control Protocol Finish) to data D7, Internet Group Management Protocol (IGMP) query & report not sent to data D8, HTTP (HyperText Transfer Protocol) status code 500 returned to D9, and D10 to D10 Status code 201 non-transmission is also stored.

  Further, in the case of the present embodiment, the storage unit 50 stores the analysis result in accordance with an instruction of the control unit 12. By this, when it becomes necessary to generate a simulated fault condition for the communication network 20d in the future, it is possible to generate a simulated fault of an appropriate layer using stored analysis results and simulated fault condition data 152. It becomes.

  Next, an analysis operation when a new communication network 20d is connected to the gateway device 10 according to the present embodiment will be described with reference to FIG. When the communication network 20d is newly connected to the port 14d of the gateway device 10, the periodic signal detection unit 72 detects the period of the communication performed between the communication network 20d and the device 10 performed for a predetermined unit time. Communication is detected (step S310). After the unit time has elapsed, the translation unit 74 translates the communication protocol using the protocol stack for the detected periodic communication (step S320). The result of the communication information translated by the learning unit 70 is stored in the storage unit 50 as a history for analysis under the control of the control unit 12 (step S330).

  Here, the learning unit 70 determines whether the history has been stored by a predetermined number set in advance (step S340). If the stored history does not reach the predetermined number, the process returns to step S310 to continue detection, translation and storage of the communication. On the other hand, when the history is stored for a predetermined number, the analysis unit 76 analyzes the failure detection method of the newly connected communication network 20d based on the history stored so far (step S350). After analyzing the fault detection method of the communication network, the storage unit 50 stores the analysis result (step S360).

  As described above, by using the gateway device 10 according to the present embodiment, it is possible to automatically analyze the failure detection method of the newly connected communication network 20d. Therefore, even if a communication failure occurs in another communication network later without requiring a special management operation by the administrator, the gateway device 10 can use the communication network 20d based on the stored analysis result. It is possible to generate a pseudo-fault state in a suitable layer, and to prompt the communication network 20d to perform bypass switching of the communication route.

  Further, as shown in FIG. 11, if a plurality of pseudo failure state data 152 are prepared for each layer, the control of the changing unit 62 based on the data 152 makes it possible to obtain a predetermined time by the method as shown in FIG. It is possible to change the contents of the simulated fault that is generated on a case-by-case basis. As a result, even if the communication network 20d is a communication network having an automatic failure recovery function, it is possible to increase the probability of causing the communication network 20d to identify the occurrence of a failure based on the simulated failure state of the gateway device 10. . Of course, the change order of the generated pseudo state can be set arbitrarily.

  Although some embodiments of the present invention have been described above, the embodiments are not limited to the above-described embodiments, and appropriate design and operation procedures can be made as long as the present invention can be implemented. Can make changes.

10 Gateway device
14 ports
40 Monitoring Department
46 Pseudo fault generation unit
50 storage unit
52 Pseudo-fault status data
64 change part
64 Recovery section
70 Learning Department
72 Periodic signal detector
74 Translation Department
76 Analysis Unit
152 simulated fault status data

Claims (7)

A relay device interposed between the first network and the second network, the device being
A first interface connected to the first network for transmitting and receiving signals to and from the first network;
A second interface connected to the second network for transmitting and receiving signals to and from the second network;
A monitoring unit that detects a failure from the second network;
A learning unit that detects communication of the port 80 in TCP (Transmission Control Protocol) from a received signal received from the first network;
And a simulated fault generation unit configured to control generation of a simulated fault signal including an HTTP (HyperText Transfer Protocol) status code based on the detection result of the monitoring unit and the detection result of the learning unit.
The monitoring unit constantly or periodically transmits a predetermined signal to the second network via the second interface, and detects the presence or absence of a failure according to the presence or absence of a response from the second network to the predetermined signal. ,
The learning unit detects the communication from the received signal received from the first network via the first interface,
A relay apparatus characterized in that the first interface transmits the pseudo fault signal to the first network as a return. A relay device interposed between the first network and the second network, the device being
A first interface connected to the first network for transmitting and receiving signals to and from the first network;
A second interface connected to the second network for transmitting and receiving signals to and from the second network;
A monitoring unit that detects a failure from the second network;
A learning unit that detects communication of the port 80 in TCP (Transmission Control Protocol) from a received signal received from the first network;
Based on the detection result of the monitoring unit and the detection result of the learning unit, generation of a first pseudo failure signal including an HTTP (HyperText Transfer Protocol) status code or a second pseudo failure signal for terminating a TCP connection is generated. Have a department,
The monitoring unit constantly or periodically transmits a predetermined signal to the second network via the second interface, and detects the presence or absence of a failure according to the presence or absence of a response from the second network to the predetermined signal. ,
The learning unit detects the communication from the received signal received from the first network via the first interface,
The first interface transmits the first simulated fault signal to the first network as a return related to the communication when the simulated fault generation unit controls generation of the first simulated fault signal, and the simulated fault generation unit transmits the second simulated fault signal to the second network. A relay apparatus characterized by transmitting a second pseudo failure signal for terminating a TCP connection related to the communication to a first network when controlling generation of the pseudo failure signal. A first interface connected to the first network to transmit and receive signals to and from the first network; and a second interface connected to the second network to transmit and receive signals to and from the second network; Relay device between them,
A monitoring unit that transmits a predetermined signal to the second network by itself constantly or periodically via the second interface, and detects the presence or absence of a failure according to the presence or absence of a response from the second network to the predetermined signal;
Learning means for detecting the communication of the port 80 in TCP (Transmission Control Protocol) from a received signal received from the first network via the first interface, and HTTP based on the detection result of the monitoring means and the detection result of the learning means (HyperText Transfer Protocol) A program that controls generation of a pseudo fault signal including a status code, and functions as a pseudo fault generation unit that transmits the pseudo fault signal to the first network as a return to the first interface. A first interface connected to the first network to transmit and receive signals to and from the first network; and a second interface connected to the second network to transmit and receive signals to and from the second network; Relay device between them,
A monitoring unit that transmits a predetermined signal to the second network by itself constantly or periodically via the second interface, and detects the presence or absence of a failure according to the presence or absence of a response from the second network to the predetermined signal;
Learning means for detecting the communication of the port 80 in TCP (Transmission Control Protocol) from a received signal received from the first network via the first interface, and HTTP based on the detection result of the monitoring means and the detection result of the learning means (HyperText Transfer Protocol) controlling the generation of a first pseudo fault signal including a status code or a second pseudo fault signal for terminating a TCP connection, and controlling the generation of a first pseudo fault signal, the communication to the first interface The first pseudo fault signal is transmitted to the first network as a return related to the second network, and the second pseudo fault signal for terminating the TCP connection related to the communication is transmitted to the first interface when the generation of the second pseudo fault signal is controlled. (1) A program characterized in that it functions as a simulated fault generation unit to be transmitted to a network. A first interface connected to the first network to transmit and receive signals to and from the first network; and a second interface connected to the second network to transmit and receive signals to and from the second network; And controlling the relay apparatus interposed between the
The relay apparatus constantly or periodically transmitting a predetermined signal to the second network via the second interface, and detecting the presence or absence of a failure according to the presence or absence of a response from the second network to the predetermined signal; When,
The relay device detects communication of a port 80 in Transmission Control Protocol (TCP) that executes communication to the second network where the failure is detected from the received signal received from the first network via the first interface, the relay The apparatus controls generation of a pseudo fault signal including HTTP (HyperText Transfer Protocol) status code based on the pseudo fault status data relating to return, the fault and the communication, and sends the pseudo fault signal back to the first interface. And b. Causing the network to transmit. A first interface connected to the first network to transmit and receive signals to and from the first network; and a second interface connected to the second network to transmit and receive signals to and from the second network; And controlling the relay apparatus interposed between the
The relay apparatus constantly or periodically transmitting a predetermined signal to the second network via the second interface, and detecting the presence or absence of a failure according to the presence or absence of a response from the second network to the predetermined signal; When,
The relay device detects communication of a port 80 in Transmission Control Protocol (TCP) that executes communication to the second network where the failure is detected from the received signal received from the first network via the first interface, the relay The apparatus controls generation of a first pseudo failure signal including HTTP (HyperText Transfer Protocol) status code or a second pseudo failure signal for terminating a TCP connection based on the pseudo failure status data relating to the return, the failure and the communication. When controlling the generation of the first pseudo fault signal, the first interface transmits the first pseudo fault signal to the first network as a return related to the communication, and when controlling the generation of the second pseudo fault signal, the first Sending a second simulated fault signal to the first network to terminate the TCP connection involved in the communication on one interface. The method according to claim and. A first interface connected to the first network for transmitting and receiving signals to and from the first network, and a second interface connected to the second network and for transmitting and receiving signals to the second network, interposed between the first network and the second network And the relay apparatus further comprises:
A monitoring unit that transmits a predetermined signal to the second network via the second interface constantly or periodically, and detects the presence or absence of a failure according to the presence or absence of a response from the second network to the predetermined signal;
A learning unit that detects communication of a port 80 in a communication protocol TCP (Transmission Control Protocol) from a relay signal received from the first network via the first interface when going from the first network to the second network;
A simulated failure generation unit that generates an HTTP (HyperText Transfer Protocol) simulated failure state in the relay device based on the detection result of the monitoring unit and the detection result of the learning unit;
And a storage unit for storing at least second HTTP pseudo failure status data different from the first HTTP pseudo failure status data for setting the HTTP pseudo failure status generated by the pseudo failure generation unit or the first HTTP pseudo failure status data. ,
The simulated fault generation unit generates the HTTP simulated fault based on the first HTTP simulated fault status data or the second HTTP simulated fault status data,
When generating the HTTP pseudo failure state based on first HTTP pseudo failure state data, the first interface of the relay device performs processing to return an HTTP pseudo failure signal including a predetermined HTTP status code to the first network, 2. A relay apparatus characterized in that when the HTTP pseudo failure state is generated based on second HTTP pseudo failure state data, the first interface of the relay device performs processing different from the processing to be returned.

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