JP7456133B2 - Communication monitoring device, communication monitoring method, and communication monitoring program - Google Patents

Description

The present invention relates to a communication monitoring device, a communication monitoring method, and a communication monitoring program.

For example, communication systems that establish a connection and communicate with a partner system using TCP (Transmission Control Protocol)/IP (Internet Protocol) communication protocols are widely used. In the TCP protocol, after establishing a connection with the other party's system, there is no need to continue sending and receiving packets; instead, packets are sent only when necessary, and the connection is left in a state of no communication when no packets are being sent or received. can continue to be maintained. Therefore, the communication device does not notice even if the other party's system is down during a non-communication state, and only detects an abnormality in the other party's system when subsequent packet transmission fails.

The TCP protocol has a no-communication monitoring function that monitors the existence of a connection when an established connection is in a no-communication state. With this function, if no packets are received from a connection for a certain period of time or more, a no-communication monitoring packet is sent to that connection, and if no response to the no-communication monitoring packet is detected, an abnormality in that connection is detected.

Japanese Patent Application Publication No. 2010-4487 International Publication No. 2017/010079

The communication device establishes a large number of backup connections in advance for each partner system, and if an error occurs in the operational connection during communication, it switches the operational connection in which the error occurred to the backup connection to suppress communication interruptions. Communication systems are known.

However, in a communication device, after establishing a large number of backup connections, a large number of backup connections are sent all the no-communication monitoring packets all at once, so the simultaneous occurrence of a large number of no-communication monitoring packets can cause an instantaneous increase in the network load. concentrate. As a result, for example, a packet lost event may occur due to a buffer shortage in a communication device on the transmitting side or a receiving side of a non-communication monitoring packet, or a buffer shortage in a router on a communication path through which the non-communication monitoring packet passes. Connection breaks and communication delays occur.

One aspect of the present invention is to provide a communication monitoring device and the like that can reduce the concentration load caused by non-communication monitoring packet transmission.

A communication monitoring device according to one aspect includes a transmitter and a monitor. In a situation where multiple connections have been established to communicate with multiple systems, the transmitting unit monitors non-communication by distributing it to the non-communicating connections of each system during multiple time periods with intervals in between. Send a packet. The monitoring unit monitors the communication state of each connection to which the no-communication monitoring packet was sent, based on the presence or absence of a response to the no-communication monitoring packet.

According to one aspect, it is possible to reduce the concentrated load caused by non-communication monitoring packet transmission.

FIG. 1 is an explanatory diagram showing an example of a communication system according to the present embodiment. FIG. 2 is an explanatory diagram illustrating an example of a communication monitoring device. FIG. 3 is an explanatory diagram showing an example of the transmission order in the order table. FIG. 4A is an explanatory diagram showing an example of a transmission order during the first simultaneous transmission (normal). FIG. 4B is an explanatory diagram showing an example of the transmission order during the second simultaneous transmission (normal time). FIG. 4C is an explanatory diagram showing an example of the transmission order during the third simultaneous transmission (normal time). FIG. 5 is an explanatory diagram showing an example of a non-communication monitoring packet transmission operation when the communication status is normal. FIG. 6A is an explanatory diagram illustrating an example of the transmission order at the time of the first simultaneous transmission (at the time of abnormality). FIG. 6B is an explanatory diagram showing an example of the transmission order at the time of the second simultaneous transmission (at the time of abnormality). FIG. 6C is an explanatory diagram showing an example of the transmission order at the time of the third simultaneous transmission (at the time of abnormality). FIG. 7 is an explanatory diagram illustrating an example of a non-communication monitoring packet transmission operation when the communication status is abnormal. FIG. 8 is a flowchart illustrating an example of processing operations of the communication monitoring device related to transmission order registration processing. FIG. 9A is a flowchart illustrating an example of processing operations of the communication monitoring device related to monitoring packet transmission processing. FIG. 9B is a flowchart illustrating an example of processing operations of the communication monitoring device related to monitoring packet transmission processing. FIG. 10 is a flowchart illustrating an example of processing operations of the communication monitoring device related to transmission order update processing. FIG. 11 is a flowchart illustrating an example of processing operations of the communication monitoring device related to response monitoring processing. FIG. 12 is a block diagram showing an example of a computer that executes a communication monitoring program.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a communication monitoring device and the like disclosed in the present application will be described in detail based on the drawings. Note that the disclosed technology is not limited by each example. Furthermore, the embodiments shown below may be combined as appropriate to the extent that no contradiction occurs.

FIG. 1 is an explanatory diagram showing an example of a communication system 1 of this embodiment. The communication system 1 shown in FIG. 1 includes a local system 2, a plurality of partner systems 3, and a network 4. The own system 2 has a plurality of communication monitoring devices 5. Note that the communication monitoring device 5 is included in, for example, a communication device within the own system 2. The destination system 3 also has a plurality of communication monitoring devices 5A(5). Further, the communication monitoring device 5A is also included in a communication device within the partner system 3, for example. Each communication monitoring device 5 in its own system 2 simultaneously establishes a plurality of connections with a plurality of partner systems 3 when starting communication operations with the partner system 3 . The communication monitoring device 5 establishes a plurality of connections for each partner system 3 using the TCP protocol, and uses, for example, one connection among the plurality of connections as an operational connection. Furthermore, the communication monitoring device 5 uses the remaining connections other than the operational connection among the plurality of connections as backup connections. When the communication monitoring device 5 detects an abnormality in the working connection, it switches the working connection to a backup connection and takes over the communication of the working connection where the abnormality has been detected to the backup connection.

The counterpart system 3 includes, for example, three counterpart systems 3A, 3B, and 3C. The four backup connections between the local system 2 and the destination system 3A are 1-1 to 1-4, and the four backup connections between the local system 2 and the destination system 3B are 2-1 to 2-. Set it to 4. Furthermore, the four backup connections between the own system 2 and the partner system 3C are designated as 3-1 to 3-4.

In addition, when multiple spare connections for each destination system 3 are in a no-communication state for a certain period of time or more, the communication monitoring device 5 sequentially transmits a no-communication monitoring packet to the spare connections in the no-communication state. The communication monitoring device 5 monitors the communication state of each spare connection based on whether or not there is a response to the no-communication monitoring packet.

FIG. 2 is an explanatory diagram showing an example of the communication monitoring device 5. As shown in FIG. The communication monitoring device 5 shown in FIG. 2 includes a TCP protocol processing section 11 and a storage section 12. The TCP protocol processing section 11 includes a transmitting section 11A and a monitoring section 11B. In a situation where a plurality of connections are established to communicate with a plurality of destination systems 3, the transmitting unit 11A transmits a backup signal of each destination system 3 in a non-communication state in each of a plurality of time periods with intervals between them. Sends non-communication monitoring packets distributed among connections. The monitoring unit 11B monitors the communication state of each backup connection to which the no-communication monitoring packet has been transmitted, based on the presence or absence of a response to the no-communication monitoring packet.

The transmitter 11A includes a monitoring timer 21, a hold timer 22, a controller 23, and a transmission controller 24. The storage unit 12 includes a TCP table 31 and an order table 32.

One TCP table 31 is generated when the TCP protocol processing unit 11 is activated, and is a table for managing parameters common to the TCP protocol. The TCP table 31 manages the number of possible simultaneous transmissions, hold interval time, etc., which will be described later. The destination table 33 is queued in the TCP table 31, and is a table for managing parameters specific to the destination system 3, for example. The partner table 33 manages an abnormality flag that identifies whether or not the partner system 3 has an abnormality. The connection management table 34 is a table that is queued in the destination table 33 and manages the connection status of the destination system 3, such as a predetermined time period for monitoring whether or not there is a response to a non-communication monitoring packet, and the communication status of the connection. . The connection management table 34 manages a response waiting flag that identifies whether or not a response to a non-communication monitoring packet is being waited for. The order table 32 is a table that stores the transmission order of non-communication monitoring packets for backup connections, which will be described later.

The monitoring timer 21 is a timer for detecting a monitoring cycle for periodically transmitting a no-communication monitoring packet to a backup connection in a no-communication state. The timer time of the monitoring cycle is, for example, every 30 seconds. The hold timer 22 is a timer for detecting the hold interval of the no-communication monitoring packet during the monitoring cycle period when the no-communication monitoring packet is transmitted to the backup connection in response to the detection of the monitoring cycle. The timer time of the hold interval is, for example, a 50 msec interval from detection of a monitoring cycle to detection of the next monitoring cycle.

When the communication monitoring device 5 detects the monitoring cycle, it sequentially transmits the non-communication monitoring packets within the number that can be transmitted simultaneously at each hold interval. The number of simultaneous transmissions is the number of non-communication monitoring packets that can be simultaneously transmitted by the communication monitoring device 5, and corresponds to the number of packets within a range where a buffer shortage or a packet lost event does not occur, and is set to, for example, four. When the communication monitoring device 5 detects the monitoring cycle, it sequentially transmits, for example, four no-communication monitoring packets at every hold interval (50 msec) based on the transmission order described later. Based on the transmission order, the communication monitoring device 5 sequentially and simultaneously transmits the no-communication monitoring packets to the backup connections in each destination system 3, that is, up to four backup connections, at each hold interval.

That is, the communication monitoring device 5 executes simultaneous transmission (first simultaneous transmission) of a no-communication monitoring packet to the first four spare connections based on the transmission order after the first hold interval has elapsed since the detection of the monitoring cycle. Furthermore, if the communication monitoring device 5 is unable to transmit a no-communication monitoring packet to all spare connections in the first simultaneous transmission after the second hold interval has elapsed since the detection of the monitoring cycle, it executes a second simultaneous transmission. That is, the communication monitoring device 5 executes simultaneous transmission of a no-communication monitoring packet to the next four spare connections based on the transmission order. Furthermore, if the communication monitoring device 5 is unable to transmit a no-communication monitoring packet to all spare connections in the second simultaneous transmission after the third hold interval has elapsed since the detection of the monitoring cycle, it executes a third simultaneous transmission. That is, the communication monitoring device 5 executes simultaneous transmission of a no-communication monitoring packet to the next four spare connections based on the transmission order. Then, the communication monitoring device 5 repeatedly executes simultaneous transmission for each hold interval based on the transmission order until simultaneous transmission of a no-communication monitoring packet to all spare connections is completed.

The control unit 23 controls the TCP table 31 when the monitoring cycle is detected by the timeout of the monitoring timer 21. The control unit 23 sequentially queues the destination table 33 and the connection management table 34 in the order table 32 in the order in which the non-communication monitoring packets are transmitted, while referring to the TCP table 31. Register the sending order. The transmission control unit 24 controls the transmission of non-communication monitoring packets to each backup connection in each destination system 3 based on the transmission order in the order table 32. The monitoring unit 11B monitors the communication status of each backup connection based on whether there is a response within a predetermined time to the no-communication monitoring packet for each backup connection. Furthermore, the monitoring unit 11B updates the transmission order in the order table 32 based on whether there is a response to the backup connection. When the monitoring unit 11B detects a response to the non-communication monitoring packet of the backup connection within a predetermined time, it determines that the communication status of the backup connection is normal, and performs connection management of the backup connection for which the response was detected based on the transmission order in the order table 32. Delete table 34. Further, if the monitoring unit 11B does not detect a response within a predetermined time to the no-communication monitoring packet of the backup connection, the monitoring unit 11B determines that the communication status of the backup connection is abnormal, that is, the partner system 3 that manages the backup connection is abnormal. do. Then, when it is determined that the partner system 3 is abnormal, the monitoring unit 11B updates the transmission order in the order table 32 to give priority to the transmission of the no-communication monitoring packet to the backup connection of the abnormal partner system 3. do. That is, the monitoring unit 11B updates the transmission order in the order table 32 by increasing the transmission order in the partner table 33 and connection management table 34 corresponding to the partner system 3 that manages the abnormal backup connection.

FIG. 3 is an explanatory diagram showing an example of the transmission order in the order table 32. For convenience of explanation, for example, there are three destination systems 3, four backup connections (1-1 to 1-4) to the destination system 3A, and four backup connections (2-1 to 2) to the destination system 3B. -4) Assume that the destination system 3C has four backup connections (3-1 to 3-4). The destination system 3A is managed by the destination table 33 of “1”, and the connection management tables “1-1” to “1-4” of the backup connections “1-1” to “1-4” of the destination system 3A are managed. ” to manage. The partner system 3B is managed by the partner table 33 of "2", and the connection management tables "2-1" to "2-4" of the backup connections "2-1" to "2-4" of the partner system 3B are managed. ” to manage. The partner system 3C is managed by the partner table 33 of "3", and the connection management tables "3-1" to "3-4" of the backup connections "3-1" to "3-4" of the partner system 3C are managed. ” to manage.

FIG. 4A is an explanatory diagram showing an example of the transmission order at the time of the first simultaneous transmission (normal time), FIG. 4B is an explanatory diagram showing an example of the transmission order at the time of the second simultaneous transmission (normal time), and FIG. 4C is an explanatory diagram showing an example of the transmission order at the time of the third simultaneous transmission (normal time). FIG. 5 is an explanatory diagram showing an example of a non-communication monitoring packet transmission operation when the communication status is normal. When the communication status is normal, the transmission order of the no-communication monitoring packets is such that the first simultaneous transmission is directed to backup connections "1-1", "2-1", "3-1", and "1-2". Furthermore, the transmission order of the non-communication monitoring packets is such that the second simultaneous transmission is to backup connections "2-2", "3-2", "1-3" and "2-3", and the third simultaneous transmission is to backup connections "2-2", "3-2", "1-3" and "2-3". The backup connections are "3-3", "1-4", "2-4", and "3-4".

The control unit 23 starts activating the monitoring timer 21, and detects a monitoring cycle when the monitoring timer 21 times out. Referring to the transmission order in FIG. 4A, the transmission control unit 24 transmits "1-1", "2-1", "3-1" and A non-communication monitoring packet for the backup connection “1-2” is set as the first simultaneous transmission. Then, the transmission control unit 24 simultaneously transmits a non-communication monitoring packet to each protection connection as the first simultaneous transmission. If the monitoring unit 11B detects a response to the non-communication monitoring packet of the backup connections “1-1”, “2-1”, “3-1” and “1-2” within a predetermined time, the monitoring unit 11B detects “1-1”. The backup connections of ``1'', ``2-1'', ``3-1'', and ``1-2'' are determined to be normal. Then, from the transmission order in the order table 32, the monitoring unit 11B detects "1-1", "2-1", "3-1", and "1-1", which have already sent the non-communication monitoring packet in the first simultaneous transmission. 2" is deleted from the connection management table 34 for the backup connection (see FIG. 4B).

Next, the transmission control unit 24 refers to the transmission order shown in FIG. 4B, and when the second hold interval has elapsed since the detection of the monitoring cycle, "2-2", "3-2", "1-3", and " A non-communication monitoring packet for the backup connection of 2-3" is set as the second simultaneous transmission. Then, the transmission control unit 24 simultaneously transmits a non-communication monitoring packet to each backup connection as a second simultaneous transmission. If the monitoring unit 11B detects a response to the non-communication monitoring packet of the backup connections “2-2”, “3-2”, “1-3”, and “2-3” within a predetermined time, the monitoring unit 11B detects “2-2”. The backup connections of ``2'', ``3-2'', ``1-3'', and ``2-3'' are determined to be normal. Then, the monitoring unit 11B selects "2-2", "3-2", "1-3", and "2-2", which have already sent non-communication monitoring packets in the second simultaneous transmission, from the transmission order in the order table 32. 3" is deleted from the connection management table 34 for the backup connection (see FIG. 4C).

Next, the transmission control unit 24 refers to the transmission order shown in FIG. 4C, and when the third hold interval elapses after the detection of the monitoring cycle, the A non-communication monitoring packet for the backup connection "3-4" is set as the third simultaneous transmission. Then, the transmission control unit 24 simultaneously transmits a non-communication monitoring packet to each protection connection as the third simultaneous transmission. If the monitoring unit 11B detects a response to the non-communication monitoring packet of the backup connections “3-3”, “1-4”, “2-4”, and “3-4” within a predetermined time, the monitoring unit 11B detects “3-3”. The backup connections of ``3'', ``1-4'', ``2-4'', and ``3-4'' are determined to be normal. Then, from the transmission order in the order table 32, the monitoring unit 11B detects "3-3", "1-4", "2-4", and "3-3", which are the non-communication monitoring packets that have been transmitted in the third simultaneous transmission. 4" is deleted from the connection management table 34 for the backup connection. Since the communication monitoring device 5 has completed simultaneous transmission for all backup connections in the transmission order, it will wait until it detects the next monitoring cycle.

FIG. 6A is an explanatory diagram showing an example of the transmission order at the time of the first simultaneous transmission (at the time of abnormality), FIG. 6B is an explanatory diagram showing an example of the transmission order at the time of the second simultaneous transmission (at the time of abnormality), and FIG. 6C FIG. 2 is an explanatory diagram showing an example of the transmission order at the time of the third simultaneous transmission (at the time of abnormality). FIG. 7 is an explanatory diagram illustrating an example of a non-communication monitoring packet transmission operation when the communication status is abnormal. When the communication status is normal, the transmission order of the no-communication monitoring packets is such that the first simultaneous transmission is directed to backup connections "1-1", "2-1", "3-1", and "1-2". Furthermore, the transmission order of the non-communication monitoring packets is such that the second simultaneous transmission is to backup connections "2-2", "3-2", "1-3" and "2-3", and the third simultaneous transmission is to backup connections "2-2", "3-2", "1-3" and "2-3". The backup connections are "3-3", "1-4", "2-4", and "3-4".

The control unit 23 starts activating the monitoring timer 21, and detects a monitoring cycle when the monitoring timer 21 times out. When the first hold interval has elapsed since the detection of the monitoring cycle, the transmission control unit 24 refers to the transmission order shown in FIG. A non-communication monitoring packet for the protection connection 1-2'' is set as the first simultaneous transmission. Then, the transmission control unit 24 simultaneously transmits a non-communication monitoring packet to each protection connection as the first simultaneous transmission. If there is no response to the no-communication monitoring packet for the backup connection "3-1" within a predetermined period of time, the monitoring unit 11B determines that there is an abnormality in the destination system 3C that manages the backup connection "3-1." When the monitoring unit 11B determines that there is an abnormality in the destination system 3C, the monitoring unit 11B uses the information in the order table 32 to preferentially transmit the no-communication monitoring packet to the remaining backup connections in the destination system 3C in the transmission order. Sort the sending order.

In other words, as shown in the transmission order in FIG. 6B, the monitoring unit 11B sets the backup connections "3-2", "3-3", "3-4", and "2-2" as the second simultaneous transmission. Then, the monitoring unit 11B rearranges the transmission order so that the backup connections "1-3", "2-3", "1-4", and "2-4" are the third simultaneous transmission.

When the second hold interval has elapsed since the detection of the monitoring cycle, the transmission control unit 24 refers to the transmission order shown in FIG. A non-communication monitoring packet for the backup connection of 2-2" is set as the second simultaneous transmission. Then, the transmission control unit 24 simultaneously transmits a non-communication monitoring packet to each backup connection as a second simultaneous transmission. If the monitoring unit 11B detects a response to the non-communication monitoring packet of the backup connections "3-2", "3-3", "3-4", and "2-2" within a predetermined time, It is determined that the communication status of the backup connections 2", 3-3, 3-4, and 2-2 is normal. If the monitoring unit 11B detects a response to the non-communication monitoring packet of the backup connections “3-2”, “3-3”, “3-4”, and “2-2” within a predetermined time, the monitoring unit 11B Delete backup connections "3-2", "3-3", "3-4" and "2-2". In other words, the monitoring unit 11B determines from the order table 32 that the backup packets "3-2", "3-3", "3-4" and "2-2" have already been sent the non-communication monitoring packets in the second simultaneous transmission. The connection management table 34 of the connection is deleted (see FIG. 6C).

When the third hold interval has elapsed since the detection of the monitoring cycle, the transmission control unit 24 refers to the transmission order shown in FIG. A non-communication monitoring packet for the backup connection of 2-4" is set as the third simultaneous transmission. Then, the transmission control unit 24 simultaneously transmits a non-communication monitoring packet to each protection connection as the third simultaneous transmission. When the monitoring unit 11B detects a response to the non-communication monitoring packet of the backup connections “1-3”, “2-3”, “1-4” and “2-4” within a predetermined time, the monitoring unit 11B It is determined that the communication status of the backup connections "3", "2-3", "1-4", and "2-4" is normal. When the monitoring unit 11B detects a response to the non-communication monitoring packet of the backup connections “1-3”, “2-3”, “1-4”, and “2-4” within a predetermined time, the monitoring unit 11B updates the order table 32. From here, the backup connections "1-3", "2-3", "1-4", and "2-4" are deleted. In other words, the monitoring unit 11B selects from the order table 32 the backup packets "1-3", "2-3", "1-4", and "2-4" that have already sent the non-communication monitoring packets in the third simultaneous transmission. The connection management table 34 of the connection is deleted (see FIG. 6C).

Next, the operation of the communication system 1 of this embodiment will be explained. FIG. 8 is a flowchart illustrating an example of processing operations of the communication monitoring device 5 related to transmission order registration processing. In FIG. 8, the control unit 23 in the communication monitoring device 5 determines whether a monitoring cycle has been detected (step S11). When the control unit 23 detects the monitoring cycle (step S11: Yes), the control unit 23 executes an extraction operation to extract the destination table 33 having the first transmission order from the TCP table 31 (step S12).

The control unit 23 determines whether the destination table 33 exists by the extraction operation (step S13). If the destination table 33 exists (step S13: Yes), the control unit 23 performs an extraction operation to extract the connection management table 34 having the first transmission order from the destination table 33 (step S14).

The control unit 23 determines whether or not the connection management table 34 exists by the extraction operation (step S15). If the connection management table 34 exists (step S15: Yes), the control unit 23 determines whether the connection management table 34 is a connection to which a non-communication monitoring packet is to be transmitted (step S16).

When the connection management table 34 is the connection to which the non-communication monitoring packet is to be sent (step S16: Yes), the control unit 23 determines whether the destination table 33 of step S13 is present in the sequence table 32 (step S17). When the destination table 33 is present in the sequence table 32 (step S17: Yes), the control unit 23 queues the connection management table 34 of step S15 in the destination table 33 of the sequence table 32 (step S18). When the destination table 33 is not present in the sequence table 32 (step S17: No), the control unit 23 queues the destination table 33 of step S13 in the sequence table 32 (step S19). Furthermore, the control unit 23 queues the connection management table 34 of step S15 in the destination table 33.

The control unit 23 executes an extraction operation to extract the next connection management table 34 from the destination table 33 (step S20), and moves to step S35 to determine whether or not there is a connection management table 34 based on the extraction operation. do. If the control unit 23 does not detect the monitoring cycle in step S11 (step S11: No), or if the destination table 33 does not exist in step S13 (step S13: No), the control unit 23 performs the processing operation shown in FIG. end.

If the connection management table 34 does not exist in step S15 (step S15: No), the control unit 23 executes an extraction operation to extract the next destination table 33 from the order table 32 (step S21). The control unit 23 moves to step S13 to determine whether or not the destination table 33 exists by the extraction operation. Further, if the connection management table 34 is not the connection to which the non-communication monitoring packet is to be transmitted (step S16: No), the control unit 23 moves to step S20 to extract the next connection management table 34 from the destination table 33. .

When the communication monitoring device 5, which executes the transmission order registration process shown in FIG. 8, detects a monitoring period, it sequentially extracts the destination table 33 and the connection management table 34 from the TCP table 31. Furthermore, the communication monitoring device 5 distributes the spare connections of each destination system 3 and registers the transmission order of the no-communication monitoring packets in the sequence table 32. As a result, the communication monitoring device 5 can prevent concentrated loads associated with the transmission of no-communication monitoring packets.

9A and 9B are flowcharts illustrating an example of processing operations of the communication monitoring device 5 related to the no-communication monitoring packet transmission process. In FIG. 9A, the transmission control unit 24 in the communication monitoring device 5 determines whether the current timing is the elapsed timing of the first hold interval after the detection of the monitoring cycle (step S31). Note that the elapsed timing of the first hold interval is the timing when 100 msec has elapsed since the management cycle was detected. When the first hold interval has elapsed (step S31: Yes), the transmission control unit 24 executes an extraction operation to extract the first destination table 33 from the order table 32 (step S32).

The transmission control unit 24 determines whether or not the destination table 33 exists by the extraction operation (step S33). If the destination table 33 exists (step S33: Yes), the transmission control unit 24 executes an extraction operation to extract the first connection management table 34 from the destination table 33 (step S34). The transmission control unit 24 determines whether or not the connection management table 34 exists by the extraction operation (step S35).

If the connection management table 34 exists (step S35: Yes), the transmission control unit 24 sets the connection management table 34 to the simultaneous transmission set (step S36). The transmission control unit 24 determines whether the connection management table 34 in the simultaneous transmission set has reached the maximum number of simultaneous transmissions possible (step S37). Note that the number of simultaneous transmissions possible is, for example, four. When the connection management table 34 in the simultaneous transmission set reaches the maximum number of simultaneous transmissions possible (step S37: Yes), the transmission control unit 24 simultaneously transmits non-communication monitoring packets to the backup connections in the simultaneous transmission set ( Step S39). Furthermore, after simultaneously transmitting the no-communication monitoring packet to the backup connections in the simultaneous transmission set, the transmission control unit 24 turns on the response wait flag in the connection management table 34 corresponding to the backup connections (step S40). , the processing operation shown in FIG. 9A ends. The transmission control unit 24 can refer to the response waiting flag in the connection management table 34 to identify the state of waiting for a response to the non-communication monitoring packet of the backup connection.

If the number of connection management tables 34 in the simultaneous transmission set has not reached the maximum number of possible simultaneous transmissions (step S37: No), the transmission control unit 24 performs an extraction operation to extract the next connection management table 34 from the destination table 33. Execute (step S38). Then, the transmission control unit 24 moves to step S35 to determine whether or not there is the next connection management table 34 by the extraction operation. If the destination table 33 does not exist in step S33 (step S33: No), the transmission control unit 24 executes an extraction operation to extract the next destination table 33 from the order table 32 (step S41). The transmission control unit 24 moves to step S34 to extract the first connection management table 34 from the next destination table 33 by an extraction operation.

If the current timing is not the elapsed timing of the first hold interval (step S31: No), the transmission control unit 24 moves to M1 shown in FIG. 9B.

At M1 in FIG. 9B, the transmission control unit 24 determines whether the current timing is the elapsed timing of the second or subsequent hold interval after the detection of the monitoring cycle (step S51). If the current timing is the elapsed timing of the second or subsequent hold interval (step S51: Yes), the transmission control unit 24 executes the transmission order update process shown in FIG. 10 (step S52).

After executing the transmission order update process, the transmission control unit 24 executes an extraction operation to extract the first destination table 33 from the order table 32 (step S53). The transmission control unit 24 determines whether or not the destination table 33 exists by the extraction operation (step S54). If the destination table 33 exists (step S54: Yes), the transmission control unit 24 determines whether the abnormality flag in the destination table 33 is ON (step S55).

If the abnormality flag in the destination table 33 is ON (step S55: Yes), the transmission control unit 24 executes an extraction operation to extract the first connection management table 34 from the destination table 33 (step S56). The transmission control unit 24 determines whether the connection management table 34 exists by the extraction operation (step S57).

If there is a connection management table 34 (step S57: Yes), the transmission control unit 24 sets this connection management table 34 in the simultaneous transmission set (step S58). The transmission control unit 24 determines whether the connection management table 34 in the simultaneous transmission set has reached the maximum number of simultaneous transmissions possible (step S59). When the connection management table 34 in the simultaneous transmission set reaches the maximum number of simultaneous transmissions possible (step S59: Yes), the transmission control unit 24 simultaneously transmits non-communication monitoring packets to the backup connections in the simultaneous transmission set ( Step S63). Furthermore, after simultaneously transmitting the no-communication monitoring packet to the backup connections in the simultaneous transmission set, the transmission control unit 24 turns ON the response wait flag in the connection management table 34 corresponding to the backup connections (step S64). , the processing operation shown in FIG. 9B ends.

If the number of connection management tables 34 in the simultaneous transmission set has not reached the maximum number of possible simultaneous transmissions (step S59: No), the transmission control unit 24 performs an extraction operation to extract the next connection management table 34 from the destination table 33. Execute (step S60). Further, the transmission control unit 24 moves to step S57 to determine whether or not the connection management table 34 exists by the extraction operation.

If the abnormality flag in the destination table 33 is not ON (step S55: No), i.e., if the abnormality flag is OFF, the transmission control unit 24 executes an extraction operation to extract the first connection management table 34 from the destination table 33 (step S65). The transmission control unit 24 determines whether or not a connection management table 34 exists through the extraction operation (step S66).

If there is a connection management table 34 (step S66: Yes), the transmission control unit 24 sets this connection management table 34 in the simultaneous transmission set (step S67). The transmission control unit 24 determines whether the connection management table 34 in the simultaneous transmission set has reached the maximum number of simultaneous transmissions possible (step S68). If the number of connection management tables 34 in the simultaneous transmission set has not reached the maximum number of simultaneous transmissions possible (step S68: No), the transmission control unit 24 executes an extraction operation to extract the next destination table 33 (step S69). ). The transmission control unit 24 moves to step S54 to determine whether or not the destination table 33 exists by the extraction operation.

When the connection management table 34 in the simultaneous transmission set reaches the maximum number of simultaneous transmissions possible (step S68: Yes), the transmission control unit 24 simultaneously transmits non-communication monitoring packets to the backup connections in the simultaneous transmission set ( Step S70). Furthermore, after simultaneously transmitting the no-communication monitoring packet to the backup connections in the simultaneous transmission set, the transmission control unit 24 turns on the response wait flag in the connection management table 34 corresponding to the backup connections (step S71). , the processing operation shown in FIG. 9B ends.

If the current timing is not the second or subsequent hold interval lapse timing (step S51: No), or if the destination table 33 does not exist (step S54: No), the transmission control unit 24 ends the processing operation shown in FIG. 9B.

The communication monitoring device 5 that executes the monitoring packet transmission process extracts the number of backup connections that can be simultaneously transmitted from the beginning of the transmission order according to the elapsed timing of the first hold interval after the detection of the monitoring cycle. Further, the communication monitoring device 5 simultaneously transmits a non-communication monitoring packet to the extracted backup connection. As a result, the communication monitoring device 5 can reduce the concentrated load caused by the transmission of non-communication monitoring packets.

The communication monitoring device 5 extracts the number of backup connections that can be sent simultaneously from the beginning of the transmission order at each elapsed timing of the second hold interval after the detection of the monitoring cycle, and monitors the extracted backup connections for non-communication. Send packets simultaneously. As a result, the communication monitoring device 5 can reduce the concentrated load caused by the transmission of no-communication monitoring packets by distributing the transmission of no-communication monitoring packets for each hold interval.

FIG. 10 is a flowchart illustrating an example of processing operations of the communication monitoring device 5 related to transmission order update processing. In FIG. 10, the transmission control unit 24 in the communication monitoring device 5 executes an extraction operation to extract the first destination table 33 from the order table 32 (step S81), and determines whether or not there is a destination table 33 by the extraction operation. is determined (step S82).

If the destination table 33 exists (step S82: Yes), the transmission control unit 24 turns off the abnormality flag in the destination table 33 (step S83). Further, the transmission control unit 24 determines whether or not there is a connection management table 34 with the response waiting flag ON in the destination table 33 (step S84).

If there is a connection management table 34 with the response waiting flag ON in the destination table 33 (step S84: Yes), the monitoring unit 11B turns on the abnormality flag of the destination table 33 (step S85). In other words, if there is a connection management table 34 whose response wait flag is ON even though the hold interval has elapsed, the monitoring unit 11B determines that the backup connection corresponding to the connection management table 34 is abnormal. Furthermore, the monitoring unit 11B dequeues, that is, deletes, from the destination table 33 in the order table 32, the connection management table 34 whose response wait flag is ON (step S86).

After dequeuing the connection management table 34 whose response wait flag is ON, the monitoring unit 11B moves the corresponding destination table 33 in the order table 32 to the top of the transmission order (step S87). Note that moving the transmission order to the top means, for example, as shown in FIG. 6B, the connection management tables "3-2", "3-3" and " 3-4” is moved to the top with priority. Furthermore, the monitoring unit 11B executes an extraction operation to extract the next destination table 33 from the order table 32 (step S88), and proceeds to step S82 to determine whether or not there is a destination table 33 by the extraction operation. Transition.

If the destination table 33 does not exist (step S82: No), the transmission control unit 24 moves to step S53 shown in FIG. 9B in order to extract the first destination table 33 from the order table 32. If there is no connection management table 34 with the response waiting flag ON in the destination table 33 (step S84: No), the monitoring unit 11B moves to step S88 to extract the next destination table 33 from the order table 32. .

In the transmission order update process, an abnormality is determined in the partner system 3 from the presence or absence of a response to the no-communication monitoring packet, and the transmission order of the no-communication monitoring packet for the backup connection of the partner system 3 determined to be abnormal is moved to the top. As a result, the communication monitoring device 5 moves the transmission order of the abnormal partner system 3 to the top, thereby preferentially sending the non-communication monitoring packet to the backup connection in the partner system 3 that is determined to be abnormal. Can be sent.

FIG. 11 is a flowchart showing an example of the processing operation of the communication monitoring device 5 related to response monitoring processing. In FIG. 11, the monitoring unit 11B in the communication monitoring device 5 determines whether a response to the no-communication monitoring packet has been detected (step S91). When the monitoring unit 11B detects a response (step S91: Yes), it executes an extraction operation to extract the first destination table 33 from the order table 32 (step S92). The monitoring unit 11B determines whether the destination table 33 exists by the extraction operation (step S93).

If the destination table 33 exists (step S93: Yes), the monitoring unit 11B determines whether the detected response is a response of a backup connection corresponding to the destination table 33 (step S94). If the detected response is not a response of a backup connection corresponding to the corresponding destination table 33 (step S94: No), the monitoring unit 11B executes an extraction operation to extract the next destination table 33 from the order table 32 (step S95). ). The monitoring unit 11B moves to step S93 to determine whether or not the destination table 33 exists by the extraction operation.

If the detected response is a response of a backup connection corresponding to the destination table 33 (step S94: Yes), the monitoring unit 11B executes an extraction operation to extract the first connection management table 34 from the destination table 33 (step S94: Yes). S96). The monitoring unit 11B determines whether or not the connection management table 34 exists by the extraction operation (step S97). If the extracted connection management table 34 exists (step S97: Yes), the monitoring unit 11B determines whether the detected response is a response of a backup connection corresponding to the connection management table 34 (step S98).

If the detected response is not a response of a backup connection corresponding to the connection management table 34 (step S98: No), the monitoring unit 11B executes an extraction operation to extract the next connection management table 34 from the order table 32 (step S99). . The monitoring unit 11B moves to step S96 to extract the first connection management table 34 from the destination table 33.

If the detected response is a response of a backup connection compatible with the connection management table 34 (step S98: Yes), the monitoring unit 11B determines whether the response wait flag of the backup connection compatible with the connection management table 34 is ON. (Step S100). If the response wait flag of the backup connection corresponding to the connection management table 34 is ON (step S100: Yes), the monitoring unit 11B turns OFF the response wait flag of the backup connection corresponding to the connection management table 34 (step S101). The monitoring unit 11B dequeues, that is, deletes the corresponding connection management table 34 from the destination table 33 in the order table 32 (step S102). The monitoring unit 11B determines whether or not there is a connection management table 34 in the destination table 33 of the dequeued connection management table 34 (step S103).

If there is a connection management table 34 in the destination table 33 of the dequeued connection management table 34 (step S103: Yes), the monitoring unit 11B dequeues the corresponding destination table 33 from the order table 32 (step S104). . The monitoring unit 11B then ends the processing operation shown in FIG.

If the response waiting flag in the connection management table 43 is not ON (step S100: No), the monitoring unit 11B ends the processing operation shown in FIG. 11. If the connection management table 34 does not exist in the destination table 33 of the dequeued connection management table 34 (step S103: No), the monitoring unit 11B ends the processing operation shown in FIG. 11. If the monitoring unit 11B does not detect a response (step S91: No) or if there is no connection management table 34 (step S97: No), the monitoring unit 11B ends the processing operation shown in FIG. 11.

When the communication monitoring device 5 that executes the response monitoring process detects a response to the no-communication monitoring packet, it deletes the connection management table 34 of the backup connection for which the response was detected from the order table 32 . As a result, the communication monitoring device 5 can delete the backup connection to which the no-communication monitoring packet has been sent from the transmission order.

The communication monitoring device 5 detects the non-communication of each partner system 3 during each of a plurality of time periods (holding intervals) under a situation where a plurality of backup connections are established to connect the plurality of partner systems 3 by communication. Sends non-communication monitoring packets distributed to backup connections in the status. The communication monitoring device 5 monitors the communication state of each backup connection to which the no-communication monitoring packet has been transmitted, based on the presence or absence of a response to the no-communication monitoring packet. As a result, the concentrated load caused by non-communication monitoring packet transmission can be reduced. Furthermore, the communication status of the backup connection within the partner system 3 can be monitored.

The communication monitoring device 5 distributes the non-communication monitoring packets to the backup connections of each partner system 3 and sequentially transmits the non-communication monitoring packets, within the range of the number of non-communication monitoring packets that can be simultaneously transmitted. As a result, the communication monitoring device 5 can reduce the concentrated load caused by the transmission of non-communication monitoring packets by distributing the transmission of non-communication monitoring packets within the range of the number that can be simultaneously transmitted and the hold interval.

The communication monitoring device 5 distributes the no-communication monitoring packets to the remaining backup connections within the range of the number that can be sent simultaneously and sequentially transmits them for each hold interval period until the transmission of the no-communication monitoring packets to all the backup connections is completed. Send. As a result, the communication monitoring device 5 can reduce the concentrated load caused by the transmission of non-communication monitoring packets by distributing the transmission of non-communication monitoring packets within the range of the number that can be simultaneously transmitted and the hold interval.

When the communication monitoring device 5 detects an abnormality in the communication status of a backup connection, the communication monitoring device 5 gives priority to the backup connection in the destination system 3 that has established the backup connection with the abnormality within the range of the number of simultaneous transmissions possible. Sends a no-communication monitoring packet to. As a result, the communication monitoring device 5 can quickly recognize an abnormality in the communication state by preferentially transmitting a no-communication monitoring packet to the backup connection of the partner system 3 that manages the backup connection with the abnormal communication state. .

For convenience of explanation, the communication monitoring device 5 has been exemplified in the case where there are three partner systems 3, but the present invention is not limited to this and can be changed as appropriate.

Although the communication monitoring device 5 has a monitoring cycle of 30 seconds, it is not limited to 30 seconds and can be changed as appropriate. Furthermore, although the counterpart systems 3 have been shown to have the same monitoring cycle, different monitoring cycles may be set for each counterpart system 3, and can be changed as appropriate.

Although the communication monitoring device 5 sets the hold interval to 100 msec, it is not limited to 100 msec and can be changed as appropriate.

Although the case where the communication monitoring device 5 sets the number of simultaneous transmissions to "4" has been exemplified, the number of packets may be within a range in which packet loss does not occur due to simultaneous transmission of non-communication monitoring packets, and can be changed as appropriate.

Further, each component of each part shown in the drawings does not necessarily have to be physically configured as shown in the drawings. In other words, the specific form of dispersion/integration of each part is not limited to what is shown in the diagram, but all or part of it may be functionally or physically distributed/integrated in arbitrary units depending on various loads, usage conditions, etc. can be configured.

Furthermore, the various processing functions performed by each device are executed in whole or in part on a CPU (Central Processing Unit), DSP (Digital Signal Processor), FPGA (Field Programmable Gate Array), etc. Also good. Furthermore, all or any part of the various processing functions may be executed on a program analyzed and executed by a CPU or the like, or on hardware using wired logic.

Examples of areas for storing various information include RAM (Random Access Memory) such as ROM (Read Only Memory), SDRAM (Synchronous Dynamic Random Access Memory), MRAM (Magnetoresistive Random Access Memory), and NVRAM (Non-Volatile Random Access Memory). Memory).

By the way, the various processes described in this embodiment can be realized by causing a processor such as a CPU in a computer to execute a program prepared in advance. Therefore, an example of a computer that executes a program having the same functions as those in the above embodiment will be described below. FIG. 12 is a block diagram showing an example of a computer that executes a communication monitoring program.

A computer 100 that executes the communication monitoring program shown in FIG. 12 includes a communication IF (Interface) 110, an input device 120, an output device 130, a ROM 140, a RAM 150, and a CPU 160. Communication IF 110, input device 120, output device 130, ROM 140, RAM 150, and CPU 160 are connected via bus 170. Communication IF 110 communicates with communication devices within the communication network.

The ROM 140 is pre-stored with a communication monitoring program that performs the same functions as the above embodiment. The ROM 140 stores a transmission program 140A and a monitoring program 140B as the communication monitoring program. The communication monitoring program may be recorded on a computer-readable recording medium using a drive (not shown) instead of the ROM 140. The recording medium may also be, for example, a portable recording medium such as a CD-ROM, DVD disk, or USB memory, or a semiconductor memory such as a flash memory, etc.

Then, the CPU 160 reads the transmission program 140A from the ROM 140 and functions as a transmission process 150A on the RAM 150. Further, the CPU 160 reads the monitoring program 140B from the ROM 140 and functions as a monitoring process 150B on the RAM 150.

In a situation where a plurality of connections are established to communicate with a plurality of systems, the CPU 160 distributes the non-communication monitoring packets to the non-communicating connections of each system during a plurality of time periods with intervals in between. Send. The CPU 160 monitors the communication status of each connection to which the no-communication monitoring packet was sent, based on whether there is a response to the no-communication monitoring packet. As a result, the concentrated load caused by non-communication monitoring packet transmission can be reduced.

5 Communication monitoring device 11A Transmission unit 11B Monitoring unit 23 Control unit 24 Transmission control unit 32 Order table

Claims (3)

In a situation where multiple backup connections have been established among multiple connections that are connected by communication for each multiple system, the idle connection is distributed to the idle backup connections of each system during multiple time periods with intervals in between. a transmitting unit that transmits a communication monitoring packet;
a monitoring unit that monitors the communication state of each backup connection to which the no-communication monitoring packet has been transmitted based on the presence or absence of a response to the no-communication monitoring packet;
The transmitter includes:
After distributing and transmitting the no-communication monitoring packets to the backup connections of each system within the range of the number of the no-communication monitoring packets that can be transmitted simultaneously, the no-communication monitoring packets are transmitted to all the backup connections in all systems. The range of the number of packets that can be sent simultaneously to the remaining backup connections in each system until the transmission of the no-communication monitoring packets is completed to all backup connections in all systems. distributing the non-communication monitoring packets within and sequentially transmitting them for each time period;
When the monitoring unit detects an abnormality in the communication state of the backup connection, the system that has established the backup connection with the abnormal communication state is determined to be abnormal, and no communication is detected in the system that is determined to be abnormal. transmitting the non-communication monitoring packets preferentially within the range of the number that can be simultaneously transmitted to backup connections in the state;
A communication monitoring device characterized by: The information processing device
In a situation where multiple backup connections have been established among multiple connections that are connected by communication for each multiple system, the idle connection is distributed to the idle backup connections of each system during multiple time periods with intervals in between. Sends a communication monitoring packet,
Based on the presence or absence of a response to the no-communication monitoring packet, monitoring the communication state of each backup connection to which the no-communication monitoring packet was sent;
As the sending process,
After distributing and transmitting the no-communication monitoring packets to the backup connections of each system within the range of the number of the no-communication monitoring packets that can be transmitted simultaneously, the no-communication monitoring packets are transmitted to all the backup connections in all systems. The range of the number of packets that can be sent simultaneously to the remaining backup connections in each system until the transmission of the no-communication monitoring packets is completed to all backup connections in all systems. distributing the non-communication monitoring packets within and sequentially transmitting them for each time period;
When an abnormality in the communication state of the backup connection is detected, the system that has established the backup connection with the abnormal communication state is determined to be abnormal, and the backup connection in the non-communication state in the system that is determined to be abnormal is determined to be abnormal. transmitting the non-communication monitoring packets preferentially within the range of the number that can be simultaneously transmitted to;
A communication monitoring method characterized by executing processing. In a situation where multiple backup connections have been established among multiple connections that are connected by communication for each multiple system, the idle connection is distributed to the idle backup connections of each system during multiple time periods with intervals in between. Sends a communication monitoring packet,
Based on the presence or absence of a response to the no-communication monitoring packet, monitoring the communication state of each backup connection to which the no-communication monitoring packet was sent;
As the sending process,
After distributing and transmitting the no-communication monitoring packets to the backup connections of each system within the range of the number of the no-communication monitoring packets that can be transmitted simultaneously, the no-communication monitoring packets are transmitted to all the backup connections in all systems. The range of the number of packets that can be sent simultaneously to the remaining backup connections in each system until the transmission of the no-communication monitoring packets is completed to all backup connections in all systems. distributing the non-communication monitoring packets within and sequentially transmitting them for each time period;
When an abnormality in the communication state of the backup connection is detected, the system that has established the backup connection with the abnormal communication state is determined to be abnormal, and the backup connection in the non-communication state in the system that is determined to be abnormal is determined to be abnormal. transmitting the non-communication monitoring packets preferentially within the range of the number that can be simultaneously transmitted to;
A communication monitoring program that causes a computer to execute processing.

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