JP2023125007A - Communication device and communication method - Google Patents

Abstract

To provide a communication device having a duplex configuration capable of, when a failure occurs in a line connecting first and second main control devices, appropriately setting both of them respectively to an operation system and a standby system, and a communication method thereof.SOLUTION: A communication device 500 having a duplex configuration includes: first and second communication function units; a first main control device 100 and a second main control device 200 which are set to a standby system or an operation system, and control operation of the first communication function unit or the second communication function unit when being set to the operation system. Each of the first and second main control devices includes: an IP communication unit connected with an IP network; and an operation system/standby system determination processing unit which determines whether or not a main control device on a counterpart side among the first and second main control devices is under operation, and performs system switching where the processing unit sets itself to the standby system when it is determined being under operation, and sets itself to the operation system when it is determined being not under operation.SELECTED DRAWING: Figure 2

Description

The present invention relates to a communication device, and particularly to a communication device having a duplex configuration and a communication method thereof.

As a redundant control device that increases fault tolerance, a monitoring unit that monitors the operational status of the first and second components forming the redundant component appropriately sets the active system and standby system to the active system and standby system, respectively. A device that performs switching has been proposed (for example, see Patent Document 1).

In addition, the first and second components forming the redundant component are connected to each other by a dedicated line, and while using the dedicated line to exchange information regarding the operational status of each other, based on the operational status of the other side. A device that performs switching between an active system and a standby system has been proposed (for example, see Patent Document 2).

Japanese Patent Application Publication No. 2013-12094 JP2018-37888A

By the way, in the device employing the duplex configuration described above, the first and second components are connected to each other in order to communicate with each other to acquire information regarding the operating status of each of the first and second components. If a problem occurs in the wiring, it becomes impossible to check the operating status of the component on the other side. Therefore, if the operation status of the other party cannot be confirmed, it is conceivable to determine that a failure has occurred on the other party and switch the own device from the standby system to the active system.

However, for example, even if there is no fault in the component on the other side and it is operating correctly as the active system, the own device is set to the active system, and both the first and second components become the active system. A problem occurs.

Therefore, there is a problem in that the communication operation using the duplex configuration cannot be continued normally until the wiring connecting the first and second components is repaired to eliminate the fault.

Therefore, the present invention provides a duplex system that allows the first and second components to be appropriately set as an active system and a standby system even if a failure occurs in the wiring that connects the first and second components. An object of the present invention is to provide a communication device and a communication method having the above configuration.

The communication device according to the present invention includes a first communication function unit and a second communication function unit, and is set to a standby system or an active system, and when set to the active system, the first communication function unit and the second communication function unit are set to a standby system or an active system. A communication device with a duplex configuration including first and second main control devices that control operations of a communication function unit, each of the first and second main control devices controlling a communication unit connected to an IP network. and determine whether the other main controller of the first and second main controllers is in operation via the IP network, and when it is determined that the main controller is in operation; has an active system/standby system determination processing unit that performs system switching that sets itself as the standby system, and sets itself as the active system when it is determined that it is not in operation.

The communication method according to the present invention includes first and second communication functional units, and when set to a standby system or an active system, and when set to the active system, the first communication functional unit and the second communication functional unit. A communication method performed by each of the first and second main control devices of a communication device with a duplex configuration, the communication device including first and second main control devices controlling operations of functional units, the communication method being connected to an IP network. By doing so, it is determined via the IP network whether the other main controller of the first and second main controllers is in operation, and if it is determined that it is in operation; When it is determined that it is not in operation, it sets itself as the standby system, and when it is determined that it is not in operation, it performs system switching to set itself as the active system.

In the present invention, each of the first and second main control devices having a redundant communication configuration communicates with the other main control device through communication via an IP (Internet Protocol) network to determine the operating status (in operation, standby) of the other main control device. I'm trying to get it.

As a result, even if there is a failure in the wiring that connects the first and second main controllers in order to obtain the operational status of the other party's main controllers, one of the first and second main controllers It becomes possible to appropriately set one as the active system and the other as the standby system.

1 is a block diagram showing the configuration of a communication system 1000. FIG. FIG. 2 is a block diagram showing the internal configuration of a duplex communication device 500 as a communication device according to the present invention. FIG. 2 is a communication flow diagram showing an example of communication operations performed between main controllers 100 and 200 after startup. FIG. 6 is a diagram showing a communication flow when a failure occurs in cables 30, 40, 50, and 60 after main controllers 100 and 200 are set to standby and active, respectively. 5 is a communication flow diagram illustrating an example of communication operations performed between the main control devices 100, 200 and the Ethernet switch 51 in failure handling processing. FIG. An example of a communication operation performed between the main control devices 100 and 200 and the Ethernet switch 51 is shown in a failure response process initiated by the main control device 200 in a state where both the main control devices 100 and 200 are in operation. It is a communication flow diagram. FIG. 2 is a communication flow diagram illustrating an example of communication operations performed between the main control devices 100 and 200 and the Ethernet switch 51 when the main control devices 100 and 200 simultaneously execute failure handling processing. FIG. 3 is a communication flow diagram showing communication operations performed between the main control devices 100 and 200 and the Ethernet switch 51 when the main control devices 100 and 200 execute failure handling processing that takes system switching priorities into consideration.

FIG. 1 is a block diagram showing a communication system 1000 including a communication device according to the present invention.

As shown in FIG. 1, the communication system 1000 includes a duplex communication device 500, an Ethernet switch 51, a router 52, an intranet 53, an external device 54, and a public IP (Internet Protocol) network connected to the duplex communication device 500. Contains 55.

FIG. 2 is a block diagram showing an example of the internal configuration of a duplex communication device 500 as a communication device according to the present invention.

As shown in FIG. 2, the redundant communication device 500 is composed of main controllers 100 and 200 as redundant components, and terminal line accommodating parts A11, A12, B13 to B16 as function providing parts.

Each of the terminal line accommodation units A11, A12, B13 to B16 accommodates various types of terminals such as telephones and FAX (facsimile) connected to the main controllers 100 and 200, as well as public network lines or private network dedicated lines. A line is connected to it, and it is deployed as a device used by communication control devices such as business phones. As shown in FIG. 2, the terminal line accommodation units A11, A12, B13 to B16 are connected to the main controllers 100 and 200 via cables 17 to 20, 30, 40, 50 and 60 for transmitting control signals and audio signals. connected.

Each of the terminal line accommodation units A11, A12, B13 to B16 performs the service function of the business phone by connecting the devices to be used and exchanging audio signals according to instructions (control signals) from the main controller 100 or 200. provide.

The main controller 100 is connected to each of the terminal line accommodating units A11, A12, B13 to B16 via cables 30 and 40, and the main controller 200 is connected to each of the terminal line accommodating units A11, A12 via cables 50 and 60. , B13 to B16.

In addition, in the redundant communication device 500, the status of the main control devices 100 and 200 as a redundant configuration is monitored via the cables 30, 40, 50, and 60 through which control signals and audio signals for providing business phone service functions flow. One of its characteristics is that it uses a proprietary signal system for communication.

The main controllers 100 and 200 are provided via a cable 30 or 40 and a cable 50 or 60 separately from the control signal channel for the normal terminal line accommodation section in order to determine the active system and standby system. Data regarding the operational status is exchanged with each other using a dedicated channel.

Note that the dedicated channel is a control signal that is allocated for checking the status of the main controller. For example, the main controller 100 transmits data on the dedicated channel to the cable 50 via the cable 30 and a hardware switch (not shown) included in the terminal line accommodation section A11. Similarly, the main controller 100 transmits data on the dedicated channel to the cable 60 via the cable 40 and a hardware switch (not shown) included in the terminal line accommodation section A12.

Each of the main controllers 100 and 200 includes a memory RG that holds operational status information 31, redundant control data 32, and IP information 41, an active system/standby system determination processing section 33, an IP duplication determination processing section 42, and an IP communication 43.

The operational state information 31 is information indicating whether the own device and other devices are in an active state or a standby state, respectively. For example, the operation state information 31 held in the memory RG included in the main control device 100 indicates whether the main control device 100 is the own device and the main control device 200 is another device, and whether each state is an active system or a standby system. This information indicates whether the above applies. On the other hand, the operational state information 31 held in the memory RG included in the main control device 200 indicates whether the main control device 200 is the own device and the main control device 100 is another device, and whether each state is an active system or a standby system. This information indicates whether the above applies.

The duplex control data 32 indicates which of the main controllers 100 and 200 is preferentially switched to the standby system when there is a conflict between the two systems to become the active system. For example, the memory RG stores in advance redundant control data 32 that is associated with the main controllers 100 and 200 and represents the priority for switching between the active system and the standby system (hereinafter also referred to as system switching). There is. Note that the memory RG of each of the main control devices 100 and 200 stores duplex control data 32 representing mutually different priorities.

The IP information 41 is, for example, a MAC address. That is, the IP information 41 stored in the memory RG of the main control device 100 indicates the MAC address of the main control device 100, and the IP information 41 stored in the memory RG of the main control device 200 indicates the MAC address of the main control device 100. The MAC address of the device 200 is shown.

The main controllers 100 and 200 can be connected to an IP network 55 via an Ethernet switch (hereinafter also referred to as L2SW) 51 by an IP communication unit 43 included in each of the main controllers 100 and 200 .

The Ethernet switch 51 is a switch that aggregates the duplex communication devices 500 so that they appear to be one communication device from the outside. This Ethernet switch 51 connects the duplex communication device 500 to a public IP network 55 via a router 52 or an intranet 53 provided at the same base as the duplex communication device 500.

The internal operation of duplex communication device 500 will be described in detail below.

When the main controllers 100 and 200 are powered on, the main controller control program is executed. As a result, first, for example, the active system/standby system determination processing unit 33 of the main control device 100 determines the current state of the own device based on the state (active system, standby system) at the time of the previous startup indicated by the operational status information 31. Create information that represents the status (starting, operating, standby). Then, the main controller 100 transmits the status inquiry signal 101 including status information representing the status at the time of the previous startup (active system, standby system) and the current status (starting up, in operation, standby) to the dedicated channel. control signals to the cables 30 and 40. At this time, the control signal is assigned to a dedicated channel for status monitoring of the main control device, and is transferred to the other party's main control device via the terminal line accommodation units A11 and A12. The main controller that receives the control signal analyzes the state information included in the control signal, that is, the state of the other party (the state at the time of the previous startup, the current own state), and adjusts its own state based on the state of the other party. Determine the status (active system, standby system). Then, a status inquiry response signal 102 containing information indicating the determination result is sent back to the other party's main control device as a control signal for the dedicated channel.

By the way, when the power is turned on normally, both main controllers start operating at approximately the same timing. Therefore, the main controllers 100 and 200 each
Status at last startup: None Status of own device: Starting Receives a status inquiry signal containing status information.

At this time, the state of each of the main controllers 100 and 200 is also
Status at last startup: None Status of own device: Booting, and will be exactly the same.

Therefore, the active system/standby system judgment processing unit 33 of each of the main control devices 100 and 200 determines whether the main control devices 100 or 200 One of them is in operation and the other is on standby. In other words, between the main controllers 100 and 200, the one holding the duplex control data 32 indicating a higher priority is in operation, and the one holding the duplex control data 32 indicating a lower priority is on standby. decide.

As a result, the operation status information 31 regarding the operation status of the main controller 100 is
Status at last startup: None Status of own device: Set to In operation.

On the other hand, the operation status information 31 regarding the operation status of the main controller 200 is
Status at last startup: None Status of own device: Set to Standby.

After such settings, the main control device 200 sends back a status inquiry response signal 102 that includes the state of own device: Standby as the status information to the other party's main control device 100 as a control signal for the dedicated channel. Upon receiving this, the main control device 100 uses its own active system/standby system determination processing unit 33 to determine that the state of its own device is in operation, and overwrites the operational state information 31 representing that fact in the memory RG. . Then, the main control device 100 notifies the terminal line accommodation unit A11 that it is the active system. Upon receiving the notification, the terminal line accommodating unit A11 switches path connections for control signals and audio signals using the main control device 100 as the active system. This makes it possible to provide the service function of a business phone by connecting the devices in use according to instructions (control signals) from the main control device 100 and exchanging audio signals.

FIG. 3 is a communication flow diagram showing an example of communication operations performed between main controllers 100 and 200 after the above-described initial startup is completed and operation as a business phone is started.

Note that communication between the main controllers 100 and 200 is actually performed via the terminal line accommodating parts A11, A12, and the cables 30, 40, 50, and 60, but in FIG. , the descriptions of the cables 30, 40, 50, and 60 are omitted.

First, the main control device 200 in the standby state transmits a status inquiry signal 101 in order to monitor the communication state of the main control device 100 in the active state at regular intervals, and the response, that is, the state Depending on the presence or absence of the inquiry response signal 102, the current state of the duplex main controller is updated.

In other words, if there is no failure in the active main controller 100, the main controller 100 will send the status inquiry response signal after the main controller 200 transmits the status inquiry signal 101 until a predetermined period of time elapses. 102 is returned. At this time, the main control device 200 continues the state because its own state is in standby and the state of the other party (main control device 100) indicated by the state inquiry response signal 102 is in operation. do.

However, when a failure occurs in the active main control device 100, the status inquiry response signal 102 is not returned even after a predetermined period of time has elapsed since the status inquiry signal 101 was sent. Therefore, if the status inquiry response signal 102 is not returned after a predetermined period of time has elapsed after transmitting the status inquiry signal 101, the standby main controller 200 resends the status inquiry signal 101. Here, if the status inquiry response signal 102 is not returned, the main control device 200 repeatedly executes the process of retransmitting the status inquiry signal 101 described above a predetermined number of times. Even so, if the status inquiry response signal 102 is not returned from the active main controller 100, the standby main controller 200 determines that a failure has occurred in the active main controller 100.

That is, the main controller 200 performs failure detection indicating that a failure has occurred when there is no reply of the status inquiry response signal 102 in response to the transmission of the status inquiry signal 101.

Upon such failure detection, the main control device 200 switches the state of its own device from standby to operation. The main control device 200 then overwrites the operation state information 31 in the memory RG indicating that the main control device 200 is in operation and the other device is in a failure state.

Thereafter, when the main control device 100 recovers from the failure state, the main control device 100 transmits to the main control device 200 a state inquiry signal 101 including state information indicating that the state of the main control device 100 is undetermined. When the main control device 200 that is being switched during operation receives this status inquiry signal 101, the operation status information 31 held in its own memory RG indicates that the state of the own device is in operation. Therefore, a status inquiry response signal 102 including status information indicating that the status of the own device is in operation is transmitted to the main control device 100.

Upon receiving the status inquiry response signal 102, the main control device 100 determines that its own device is a standby system by its own active system/standby system determination processing unit 33, and the state of its own device is on standby. Operation status information 31 indicating that the partner device is in operation is overwritten in the memory RG.

As a result of the series of communication processing described above, if a failure occurs in the main control device that was performing communication operations as an active system among the main control devices 100 and 200, the main device that was set as a standby system becomes operational. system and continue communication operations.

By the way, according to the series of communication processes described above, when the failure of main control device 100 is recovered, mutual communication between main control devices 100 and 200 using status inquiry signal 101 and status inquiry response signal 102 is restarted. As a result, each of the main controllers 100 and 200 can acquire each other's status information (active system, standby system), so based on the acquired status information, one of the main controllers 100 and 200 can be appropriately configured. It is possible to set one as a standby system and the other as an active system.

However, if a failure occurs in the communication path between the main controllers 100 and 200, that is, the cables 30, 40, 50, 60, such as a disconnection or short circuit, communication between the main controllers 100 and 200 becomes impossible, and the state It becomes impossible to obtain information (active system, standby system). As a result, each of the main controllers 100 and 200 cannot grasp the operational status of the other, and it is not possible to appropriately set one of the main controllers 100 and 200 as an active system and the other as a standby system. It becomes difficult.

FIG. 4 shows that cables 30, 40, 50, and 60 are damaged after main controllers 100 and 200 are set to standby and active, respectively, by communication of status inquiry signal 101 and status inquiry response signal 102. FIG. 3 is a diagram illustrating a communication flow when a problem occurs.

As shown in FIG. 4, after the failure occurs, the standby main controller 200 continues to repeat the status inquiry signal 101 and send it to the main controller 100, but the failure occurs in the cables 30, 40, 50, and 60. Therefore, the main control device 100 cannot receive this. Therefore, although the status inquiry signal 101 has been transmitted a predetermined number of times, the status inquiry response signal 102 as a response has not been returned, so the main controller 200 transmits the status inquiry signal 101 a predetermined number of times. 60), and switches itself from the standby system to the active system. Note that since the main control device 100 is not accessed in any way, the current state of the active system is maintained, and both the main control devices 100 and 200 become the state of the active system.

Therefore, in the redundant communication device 500, in order to avoid the problem that both the main control devices 100 and 200 become active, when it is determined that the main control device on the other side is malfunctioning, the system is immediately switched off. Instead of switching, perform the following failure handling process.

That is, in the failure handling process, first, the IP communication unit 43 of the main control device (100 or 200) that has made the above failure determination transmits an ARP (Address Resolution Protocol) request message to the Ethernet switch 51. The ARP request message includes IP address #0, which is the active IP information of the main control device of the business phone, as a target IP address, and the MAC address of the main control device of the transmission source. Note that since the ARP request message is a broadcast IP packet, the IP communication unit 43 of each of the main controllers 100 and 200 receives the ARP request message via the Ethernet switch 51, router 52, and the IP network.

The main control device that receives the ARP request message determines whether the target IP address indicated in the ARP request message is the same as its own IP address. At this time, if it is determined that the target IP address indicated in the ARP request message is the same as its own IP address, the main control device that received the ARP request message sends the ARP reply message to the Ethernet switch 51, router 52, It is sent to the main controller having the source's MAC address via the IP network.

During this time, the main control device that sent the ARP request message is in a state of waiting to receive an ARP reply message for a predetermined waiting time. Here, if the ARP reply message 111 is not returned (received) within the waiting time, the IP duplication determination processing unit 42 of this main control device determines that the device with IP address #0 on the IP network (53, 55) In other words, it is determined that there is no device (main controller) in operation with a duplicate IP address. As a result, the active/standby system determination processing unit 33 of the main controller that sent the ARP request message determines that the other main controller is in a standby state, and changes itself from the standby system to the active system. Switch.

On the other hand, if the ARP reply message is received within the waiting time, the IP duplication determination processing unit 42 of the main control device determines whether there is another device on the IP network 55 and the intranet 53 that uses IP address #0 redundantly. In other words, it is determined that there is an operating main control device. Then, the IP duplication determination processing unit 42 determines that the MAC address of the transmission source indicated in the ARP reply message 111 is the same as the MAC address indicated in the IP information 41 of the other party's main control device acquired or set in advance. Determine whether or not.

If it is determined that they are the same, the IP duplication determination processing unit 42 determines that another device that uses IP address #0 redundantly is the main control device in operation on the other party. As a result, the active system/standby system judgment processing unit 33 of the main control device that received the ARP reply message determines that the MAC address of the transmission source indicated in the ARP reply message is the main control device of the other party (in operation). Therefore, set the own device as a standby system and retry failure detection. In other words, at this time, the active system/standby system determination processing unit 33 of the main control device that has received the ARP reply message maintains the standby state and indicates that it is in operation if its own device is currently on standby. If so, perform a system switchover from the active system to the standby system.

Note that if it is determined that the MAC address of the transmission source of the ARP reply message 111 does not match the MAC address of the main control device 100, the IP duplication determination processing unit 42 determines that the transmission source is the main controller of the duplex communication device 500. It is determined that the device is not a device, but an external network device (IP-connected device such as a computer router). Therefore, the active system/standby system judgment processing unit 33 saves the alert information urging the address change of the external network device that is the source of the transmission in its own memory RG, without changing the state of its own device (standby system). .

FIG. 5 is a communication flow diagram showing an example of communication operations performed between the main controllers 100, 200 and the Ethernet switch 51 through the above-described failure handling process.

As shown in FIG. 5, although the standby main controller 200 has transmitted the status inquiry signal 101 to the main controller 100 a predetermined number of times, the status The inquiry response signal 102 is not returned. Since the status inquiry response signal 102 is not returned, the main control device 200 determines that there is a failure, and executes the following failure handling process.

That is, first, the main control device 200 sends an ARP request message 110 representing the active IP address #0 of the main control device of this business phone and the MAC address #2 of the main control device 200 as target IP addresses to the Ethernet switch 51. Send to. ARP request message 110 is sent to main controller 100 via Ethernet switch 51, router 52, and IP network. The main controller 100 that received the ARP request message 110 sends the ARP reply message 111 to the Ethernet switch 51, router 52, and It is transmitted to the main control device 200 having the source MAC address via the IP network.

During this time, the main controller 200 is in a waiting state for receiving the ARP reply message 111 for a predetermined waiting time. Here, if the main controller 200 receives the ARP reply message 111 within the waiting time, the main controller 200 detects that there is another device on the IP network 55 and the intranet 53 that uses the IP address #0 redundantly, that is, a device that is in operation. It is determined that the main controller 100 exists. Then, since the main controller 100 on the other side is in operation, the main controller 200 does not perform system switching from the standby system to the active system, and is set to maintain the current state of the own device as the standby system. I do.

As described in detail above, in the redundant communication device 500, the first communication function units (terminal line accommodation device A11, terminal line accommodation device B13, terminal line accommodation device B14) that perform various communication services including telephone call services etc. ) and the second communication function unit (terminal line accommodation device A12, terminal line accommodation device B15, terminal line accommodation device B16), two main control devices (100, 200) are placed on standby by the following configuration. Set it on either the system or the active system.

That is, each of the first and second main control devices has a communication section (43) connected to the IP network (51 to 53, 55) and the following active system/standby system determination processing section.

The active system/standby system determination processing unit (33) determines whether or not the other main control device among the first and second main control devices (100, 200) is in operation via the IP network. If it is determined that it is in operation, it sets itself to the standby system, and if it determines that it is not in operation, it sets itself to the active system.

With this configuration, each of the first and second main control devices obtains the operating status (in operation, on standby) of the other main control device through communication via the IP network. As a result, even if a failure occurs in the cables (30, 40, 50, 60) that connect the first and second main control devices to obtain the operational status of the other party's main control device, the first and second main control devices It becomes possible to appropriately set one of the second main controllers as an active system and the other as a standby system.

Next, the main controllers 100 and 200 return from the state in which both became active systems because the other could not receive the ARP reply message 111 that was sent by one of the main controllers (one The method (one for the active system and the other for the standby system) will be explained with reference to the communication flow shown in FIG.

FIG. 6 is a communication flow diagram illustrating an example of communication operations performed between the main control devices 100, 200 and the Ethernet switch 51 by failure handling processing initiated by the main control device 200.

As shown in FIG. 6, first, the IP communication unit 43 of the active main control device 200 sends an ARP request message 110 representing IP address #0 as the target IP address and MAC address #2 of the main control device 200. The data is sent to the Ethernet switch 51. That is, the main control device 200 transmits an ARP request message 110 as a broadcast IP packet, and waits for a reply from an ARP reply message 111. Here, if the main control device 200 receives the ARP reply message 111, it means that there is a device in operation that uses IP address #0 redundantly. Therefore, the main control device 200 determines whether the device in operation is the main control device 100 by checking the MAC address of the transmission source included in the ARP reply message 111. At this time, since the MAC address of the source of the ARP reply message 111 is the MAC address of the main control device 100 in operation, the main control device 200 sets its own device as the active system to avoid duplication of the active system. Switch to standby system. Then, the main control device 200 overwrites the operation state information 31 in the memory RG indicating that the state of the own device is on standby and the state of the partner device is in operation.

By the way, in the above-described recovery method, one of the main control devices 100 and 200 (main control device 200) that has become the active system executes failure handling processing.

However, both the main controllers 100 and 200 may perform failure handling processing, and there is a possibility that both the main controllers 100 and 200 are switched between the active system and the standby system at the same time.

FIG. 7 is a communication flow diagram showing communication operations performed between the main control devices 100 and 200 and the Ethernet switch 51 when each of the main control devices 100 and 200 simultaneously executes failure handling processing.

That is, when a failure is detected by the status inquiry signal 101 and status inquiry response signal 102 described above, the main controller 200 sends an ARP request message 110 to the main controller 100 via the Ethernet switch 51, as shown in FIG. At the same time, the main control device 100 transmits an ARP request message 112 to the main control device 200 via the Ethernet switch 51. At this time, upon receiving the ARP request message 110, the main control device 100 returns an ARP reply message 111 to the main control device 200 via the Ethernet switch 51. Further, upon receiving the ARP request message 112, the main control device 200 returns an ARP reply message 113 to the main control device 100 via the Ethernet switch 51.

Therefore, each of the main control devices 100 and 200 receives the ARP reply message returned from the main control device of the other party, and the main control device of the other party also identifies the device in operation that performs communication operations using IP address #0. It determines that it is, and switches itself from the active system to the standby system. In this way, unnecessary system switching of the main control device during operation may lead to interruption or termination of telephone calls and various services being provided.

Therefore, in the duplex communication device 500, each of the main control devices 100 and 200 is given a priority for implementing system switching. That is, for example, the memory RG of the main control device 100 holds the redundant control data 32 representing the first priority, and the memory RG of the main control device 200 holds the second control data 32 representing the first priority. Duplex control data 32 representing priority is held. At this time, among the main control devices 100 and 200, the one with the higher priority is switched to the active system. Conversely, system switching to the standby system is performed using the system with a lower priority. For example, if each of the main control devices 100 and 200 determines that the other main control device is also an operating device, each of the main control devices 100 and 200 generates redundant control data representing a second priority lower than the first priority. In the main control device 200 where No. 32 is maintained, system switching is performed from the active system to the standby system every time a failure is detected. In the main control device 100 in which 32 is maintained, system switching is not performed unless a failure is detected twice in succession. In addition, if each of the main control devices 100 and 200 determines that the other main control device is also not an operating device, each of the main control devices 100 and 200 transmits redundant control data representing a first priority higher than the second priority. In the main control device 100 where No. 32 is maintained, system switching is performed from the standby system to the active system every time a failure is detected. In the main control device 200 in which 32 is maintained, system switching is not performed unless a failure is detected twice in succession.

FIG. 8 shows what is done between the main controllers 100 and 200 and the Ethernet switch 51 when each of the main controllers 100 and 200 executes the failure handling process that takes into account the priority for system switching described above. FIG. 3 is a communication flow diagram showing communication operations.

When a failure of the cable 30, 40, 50, or 60 is detected by the status inquiry signal 101 and status inquiry response signal 102 described above, the main controller 200 sends an ARP request message 110 to the main controller 100 via the Ethernet switch 51. Send. Furthermore, the main control device 100 sends an ARP request message 112 to the main control device 200 via the Ethernet switch 51. At this time, upon receiving the ARP request message 110, the main control device 100 returns an ARP reply message 111 to the main control device 200 via the Ethernet switch 51. Further, upon receiving the ARP request message 112, the main control device 200 returns an ARP reply message 113 to the main control device 100 via the Ethernet switch 51.

When each of the main control devices 100 and 200 receives an ARP reply message returned from the main control device on the other side, the main control device on the other side also performs a communication operation using IP address #0 based on the ARP reply message. It is determined that the device is in operation. Here, each of the main controllers 100 and 200 checks the duplication control data 32 stored in its own memory RG. At this time, the duplex control data 32 of the main controller 200 represents the second priority (priority 2), and the duplex control data 32 of the main controller 100 represents the first priority (priority 1). Therefore, the main control device 200 performs a process of switching itself from the active system to the standby system. On the other hand, the duplex control data 32 of the main controller 100 represents a first priority higher than the second priority. At this time, according to the first priority, the main controller 100 can perform system switching when the above-mentioned failure detection operation is performed twice in a row. ), system switching is not performed. Therefore, the main control device 100 maintains the current state of the active system.

In this way, in the redundant communication device 500, the main controllers 100 and 200 each have different priorities for performing system switching, thereby preventing unnecessary operation of switching the state of the active system to the standby system. To avoid.

The main control device 200 performs system switching after a predetermined first time delay after detecting the fault based on the second priority, and the main control device 100 performs system switching based on the first priority. After the detection, system switching may be performed after a delay of a second time longer than the first time.

In addition, the redundancy control data 32 includes the priority according to the state in which it was operating before the failure was detected (active system > standby system > failure > starting) and the identification number preset in the main control device (1 > 2 ) may be used.

Incidentally, in the above embodiment, an application example for increasing fault tolerance in the case where the main control device fails has been described. By the way, the terminal line accommodation device shown in FIG. 2 has a building block configuration that can be added as appropriate. Therefore, if system switching is performed according to the failure part to improve the fault tolerance of multiple terminal line accommodation devices, the state of the duplication control data and its judgment materials described above will be used to determine whether many terminal line accommodation devices can be used. By adding a detection unit, it becomes possible to apply the present invention to further redundant configuration devices.

As described above, according to the redundant communication device 500, even if the cables (30, 40, 50, 60) connecting the main control devices 100 and 200 are out of order, the IP address obtained through communication with the IP network device By comparing the information with the IP information of the own device, it becomes possible to correctly set one of the main control devices 100 and 200 as an active system and the other as a standby system.

As a result, it is also possible to prevent operations that would cause confusion to external IP network devices in which multiple MAC addresses are notified for one IP address.

Furthermore, depending on the transmission timing of the ARP request message, when a failure is detected, both the main controllers 100 and 200 may transition from the active system to the standby system, causing both to become standby systems and the system to be unable to provide functions. This issue is also avoided by using redundant control data that indicates the priority for executing system switching. Further, by using the duplication control data described above, it is possible to prevent the above-mentioned recovery process from being repeated if the failure state continues.

11, 12 Terminal line accommodation section A
13-16 Terminal line accommodation section B
30, 40, 50, 60 Cable 32 Redundant control data 33 Active system/standby system judgment processing section 42 IP superimposition processing section 43 IP communication section 100, 200 Main controller 500 Redundant communication device

Claims (7)

first and second communication functional units;
first and second main control devices that are set to a standby system or an active system, and control operations of the first communication function unit and the second communication function unit when set to the active system; A communication device with a duplex configuration including:
Each of the first and second main controllers includes:
a communications department that connects to the IP network;
If a determination process is performed to determine whether or not the other main controller of the first and second main controllers is in operation via the IP network, and it is determined that it is in operation; The system is characterized by having an active system/standby system determination processing unit that performs system switching that sets itself as the standby system, and sets itself as the active system when it is determined that it is not in operation. communication equipment. The communication unit transmits an ARP request requesting a MAC address corresponding to the IP address of the main control device of the active system to the IP network, and subsequently waits to receive an ARP reply as a response to the ARP request,
The active system/standby system determination processing section determines whether the other party's main control device has a MAC address when the ARP reply is received and the MAC address indicated in the ARP reply matches the MAC address of the main controller of the other party. 2. The main control device according to claim 1, wherein it is determined that the main control device is in operation, but if the ARP reply cannot be received, it is determined that the main control device on the other side is not in operation. Communication device. The first and second main control devices are connected to each other via a communication path within the communication device,
The active system/standby system determination processing unit performs the determination process and the system switching when a failure occurs in the main control device of the other party or when a failure occurs in the communication path. The communication device according to claim 1 or 2. Each of the first and second main controllers transmits a status inquiry signal indicating whether it is currently in operation or on standby to the main controller of the other party via the cable. 4. Communication according to claim 3, characterized in that it is determined that the failure has occurred when a status inquiry response signal that is a response to the status inquiry signal cannot be received via the cable. Device. Each of the first and second main control devices is assigned a priority for executing the system switching,
When each of the first and second main control devices determines that the other main control device is in operation, the priority of the lower one of the first and second main control devices is determined. 5. The communication device according to claim 1, wherein the system switching is executed by the active system/standby system determination processing section of the main control device to which the communication device is assigned. Each of the first and second main control devices is assigned a priority for executing the system switching,
If each of the first and second main control devices determines that the other main control device is not in operation, the priority of the higher one of the first and second main control devices The communication device according to any one of claims 1 to 5, wherein the system switching is executed by the active system/standby system determination processing unit of the main control device to which the communication device is assigned. a first communication function unit and a second communication function unit; and a first communication function unit that is set to a standby system or an active system and controls operations of the first communication function unit and the second communication function unit when the system is set to the active system. A communication method performed by each of the first and second main control devices of a communication device with a duplex configuration including:
By connecting to an IP network, determining whether the other main controller of the first and second main controllers is in operation via the IP network;
A communication method characterized by performing system switching to set itself as the standby system when it is determined that it is in operation, and to set itself as the active system when it is determined that it is not in operation.

Images