JP2020120344A - Device status management apparatus, device status management method, and program - Google Patents

Abstract

To make it easier to understand a status of a device to be monitored.SOLUTION: A device status management apparatus includes: a packet reception unit for receiving an address resolution protocol packet from a switch for operating according to control information for transferring a packet of address resolution protocol between devices to a predetermined device status confirmation apparatus; and a device status management unit for managing statuses of source and destination devices of the address resolution protocol packet based on a status of transmission and reception of the address resolution protocol packet between the devices.SELECTED DRAWING: Figure 1

Description

The present invention relates to a device status management device, a device status management method, and a program.

In a general Local Area Network (LAN), as shown in FIG. 14, there are relay devices such as L2 switches and L3 switches, and devices such as terminals and servers that are end points of the network. A Network Management System (NMS) is generally used for the purpose of confirming the operating states of these devices existing in the LAN. In the NMS, the normality of operation of hardware is monitored between a manager and an agent such as a switch by using a standardized protocol such as SNMP (Simple Network Management Protocol). When an abnormality is found, each switch reports the fact to the NMS manager, so that the NMS manager can grasp the failure occurrence location. In addition, alive monitoring using Ping or the like may be performed on the server and the like.

Patent Document 1 discloses an inter-LAN connection device that immediately disconnects the line to reduce the cost of using the line when reception is not possible, or transfers data to another terminal when reception is not possible. It is disclosed. The LAN-to-LAN connecting device described in this document sends a node state confirmation packet PKTC for confirming the terminal state to a LAN terminal under its control. Upon receiving the confirmation packet, the normal terminal returns a response packet to the inter-LAN connecting device. On the other hand, a terminal that cannot receive data due to a cable drop or other failure does not return a response packet. The LAN-to-LAN connecting device identifies and stores the receivable/unreceivable state of the terminal according to the presence or absence of the response packet. Then, this LAN-to-LAN connecting device immediately disconnects the line when the other LAN terminal receives a call from a predetermined LAN terminal and the LAN terminal cannot receive the call. Further, the LAN-to-LAN connecting device transfers the received data to the transfer destination when the transfer destination is registered for the terminal that cannot receive.

In addition, Patent Document 2 discloses a method for detecting duplication of IP addresses by using transmission and reception of an ARP (Address Resolution Protocol) packet, which is one of address resolution protocols. Specifically, the IP address duplication diagnosis detection host described in the document sends an ARP request packet including an inspection target IP address in the same subnet as itself to each inspection target host via the LAN. Then, the IP address duplication diagnosis detection host detects the duplication of the IP address based on whether or not the ARP reply packet, which is the response packet, is returned.

Further, Patent Document 3 discloses a communication terminal including a control unit that selects a communication interface depending on the presence or absence of a response to a packet.

JP, 7-131478, A JP 2001-244945A International Publication No. 2015/083320

Open Networking Foundation (ONF), OpenFlow Switch Specifications, [online], [January 4, 2019 search], Internet <URL: https://www.opennetworking.org/software-defined-standards/specifications/> "IETF RFC 826", [online], November 1982, An Ethernet Address Resolution Protocol, [online], [January 4, 2019 search], Internet <URL: https://tools.ietf.org/ html/rfc826>

The following analysis is given by the present invention. The life and death monitoring by the Ping has a problem that if the IP (Internet Protocol) address of the target device is not known in advance, the Ping packet cannot be delivered to the destination device in the first place, and the life and death monitoring cannot be performed. is there. Further, even if the IP address of the target device can be grasped, the Ping packet is a packet that is not necessary for communication between the terminals, and there is a problem that the band of the network is consumed extra. In this respect, the same is true of Patent Document 1, and an extra node state confirmation packet PKTC needs to be transmitted and received. Further, in these methods, as the number of devices to be monitored increases, the bandwidth of the network will be pressed more.

In addition to the life and death monitoring, there is a need to grasp whether or not the target device has previously communicated with another device or the like. In order to meet such needs, it is conceivable to check the transfer table of switches and the like on the route. However, the information in the transfer table is generally deleted after a certain time by a process called Ageout (also called aging). Therefore, there is a problem that it is not possible to distinguish whether the state is “the device has been communicated with in the past but was deleted by the Ageout process” or “the device was never communicated in the first place”. is there.

An object of the present invention is to provide a device status management device, a device status management method, and a program that can contribute to facilitating the grasp of the status of a device to be monitored.

According to a first aspect, a packet receiving unit that receives a packet of the address resolution protocol from a switch that operates according to control information that causes a packet of the address resolution protocol between devices to be transferred to a predetermined device status confirmation device; There is provided a device state management device including a device state management unit that manages the states of the source and destination devices of the address resolution protocol packet based on the exchanged state of the address resolution protocol packet between them.

According to a second aspect, a packet of the address resolution protocol is received from a switch operating according to control information for transferring a packet of an address resolution protocol between devices to a predetermined device status confirmation device, and an address resolution between the devices is resolved. There is provided a device state management method for managing the states of a source device and a destination device of a packet of the address resolution protocol based on an exchange state of a protocol packet. The method is tied to a particular machine, a computer, which analyzes Address Resolution Protocol packets sent from the switch.

According to a third aspect, a process of receiving a packet of the address resolution protocol from a switch that operates according to control information that causes a packet of the address resolution protocol between devices to be transferred to a predetermined device status confirmation device; A program for causing a computer to execute processing for managing the states of the source and destination devices of the address resolution protocol packet based on the transmission/reception state of the address resolution protocol packet is provided. This program is input to a computer device from an input device or an external device through a communication interface, stored in a storage device, and drives a processor according to predetermined steps or processes, and if necessary, stages the processing results including intermediate states. Each can be displayed via a display device or can communicate with the outside via a communication interface. A computer device therefor typically includes, for example, a processor, a storage device, an input device, a communication interface, and optionally a display device that can be connected to each other by a bus.

According to the present invention, it is possible to easily grasp the state of the device to be monitored.

It is a figure which shows the structure of one Embodiment of this invention. It is a figure for demonstrating the apparatus state management function of the apparatus state management apparatus of one Embodiment of this invention. It is a figure which shows the structure of the apparatus state management apparatus of the 1st Embodiment of this invention. It is a figure which shows an example of the flow entry set to the switch of the 1st Embodiment of this invention. It is a figure which shows the ARP status information (apparatus status information) which the apparatus status management apparatus of the 1st Embodiment of this invention manages. It is a figure which shows an example of the transition table of the ARP state which the packet analysis part of the apparatus state management apparatus of the 1st Embodiment of this invention hold|maintains. It is a figure which shows an example of the transition table of the ARP state which the recorded information analysis part of the apparatus state management apparatus of the 1st Embodiment of this invention holds. It is an activity diagram showing operation|movement of the 1st Embodiment of this invention. FIG. 9 is a diagram showing ARP status information (apparatus status information) at the time when steps S8 and S12 of FIG. 8 are finished. FIG. 9 is a diagram showing ARP status information (apparatus status information) at the time when steps S28 and S31 of FIG. 8 are finished. FIG. 6 is an activity diagram showing an updating operation of ARP status information (device status information) of a recorded information analysis unit of the device status management device of the first exemplary embodiment of the present invention. FIG. 12 is a diagram showing ARP status information (apparatus status information) at the time when step S46 of FIG. 11 ends. FIG. 7 is an activity diagram showing an updating operation of ARP status information (device status information) by the packet analysis unit of the device status management device of the first exemplary embodiment of the present invention. It is a figure for demonstrating the function of NMS. It is a figure which shows the structure of the computer which comprises the apparatus state management apparatus of this invention.

First, an outline of one embodiment of the present invention will be described with reference to the drawings. The reference numerals in the drawings attached to this outline are added to the respective elements for convenience as an example for facilitating understanding, and are not intended to limit the present invention to the illustrated modes. Further, the connecting lines between blocks in the drawings and the like referred to in the following description include both bidirectional and unidirectional. The unidirectional arrows schematically show the flow of main signals (data), and do not exclude bidirectionality. The program is executed via a computer device, and the computer device includes, for example, a processor, a storage device, an input device, a communication interface, and a display device as necessary. This computer device is configured to be able to communicate with a device (including a computer) inside or outside the device via a communication interface regardless of whether it is wired or wireless. Further, although there are ports or interfaces at the input/output connection points of each block in the figure, they are not shown. Further, in the following description, “A and/or B” is used to mean at least one of A and B.

In one embodiment thereof, the present invention can be realized by a device status management device 10 including a packet reception unit 11 and a device status management unit 12, as shown in FIG. More specifically, the device status management device 10 is connected to the switch 20. The switch 20 transfers the packet of the address resolution protocol between the devices (device A and device B) to the device state management device 10 according to the control information. In the following description, ARP (Address Resolution Protocol) is used as the address resolution protocol, but the address resolution protocol is not limited to ARP. For example, instead of the ARP packet, a packet of ND (Neighbor Discovery) protocol that provides an address resolution function in IPv6 (Internet Protocol version 6) can be used.

The packet receiving unit 11 receives the packet of the address resolution protocol (hereinafter, ARP packet) from the switch 20. Then, the device state management unit 12 manages the states of the transmission source device and the transmission destination device of the ARP packet based on the transmission/reception state of the packet of the address resolution protocol between the devices.

Here, a method of managing the device status by the device status management unit 12 will be described with reference to FIG. In the following description, it is assumed that the device A sends an ARP request packet (ARP Request) to the device B, and the device B sends an ARP response packet (ARP Reply) to the device A.

The left side of FIG. 2 shows the state transition of the device A that has transmitted the ARP request packet (ARP Request). The right side of FIG. 2 shows the state transition of the device B which has received the ARP request packet (ARP Request). In the initial state, neither device A nor device B exchanges ARP packets. Therefore, the device status management device 10 manages the devices A and B as "no ARP status information".

When the device A transmits an ARP request packet (ARP Request) to the device B, the device state management device 10 receives the ARP request packet (ARP Request) from the switch 20. Upon receiving the ARP request packet (ARP Request), the device state management device 10 recognizes that the device A has started communication and changes the state of the device A to “normal” (“normal” in FIG. 2).

On the other hand, since the device B does not always correctly receive the ARP request packet (ARP Request), the device state management device 10 changes the state of the device B to “during state confirmation” (“state confirmation in FIG. 2”). During").

After that, when the device B transmits an ARP response packet (ARP Reply), the device state management device 10 receives the ARP response packet (ARP Reply) from the switch 20. Upon receiving the ARP reply packet (ARP Reply), the device status management device 10 recognizes that the device B has started ARP communication and changes the status of the device B to “normal” (“normal” in FIG. 2). In this case, the device status management device 10 keeps the status of the device A as “normal” because it is known that the device A is normal by transmitting the ARP request packet (ARP Request) (see FIG. 2). "normal").

On the other hand, when the device B does not send the ARP reply packet (ARP Reply) and a certain period of time has passed (time out), the device state management device 10 determines that the device B is abnormal and determines the state of the device B. Change to "abnormal" ("abnormal" in FIG. 2). In this case, the device status management device 10 keeps the status of the device A as “normal” because it is known that the device A is normal by transmitting the ARP request packet (ARP Request) (see FIG. 2). "normal").

As described above, the device state management device 10 manages the states of the transmission source device and the transmission destination device of the ARP packet based on the transmission/reception state of the ARP packet between the devices. As a result, the state of the device to be monitored can be grasped without exchanging a special packet represented by Ping.

[First Embodiment]
Subsequently, a first embodiment of the present invention will be described in detail with reference to the drawings. FIG. 3 is a diagram showing the configuration of the device status management device according to the first embodiment of the present invention. Referring to FIG. 3, the device state management device 100 connected to the switches 200A and 200B is shown.

The switches 200A and 200B are devices that relay packets between devices that are endpoints of the network, such as terminals and servers that communicate via the network. Further, the switch 200A and the switch 200B have a function as the OpenFlow switch of Non-Patent Document 1.

In the following description, it is assumed that the device status management device 100 is connected to the switches 200A and 200B via a control channel and functions as an OpenFlow controller. The flow entry shown in FIG. 4 is set in the switches 200A and 200B. In the example of FIG. 4, a flow entry that sets a packet in which 0806 (ARP) is set in the Ethernet Type field (Ethernet Type Number) of the packet header to not only the normal destination (NORMAL) but also the controller (CONTROLLER) Is set. Therefore, when the switch 200A and the switch 200B receive the packet of the ARP communication, the switch 200A and the switch 200B also transmit the packet to the device state management device 100 separately from the specified destination.

The device status management device 100 includes a packet analysis unit 110, a packet information recording unit 120, a recorded information analysis unit 130, and a device status information providing unit 140.

The packet information recording unit 120 holds ARP status information (device status information) that represents status information of a device connected to the network. FIG. 5 is a diagram showing an example of ARP status information. In the example of FIG. 5, the terminal A and the terminal B specified by the IP address are known. Further, in the example of FIG. 5, no ARP packet has been exchanged between the terminals A and B, so that the ARP status field is “no ARP status information”. Further, the ARP state last update time is also (no update). That is, in this state, the existence of the terminals A and B is known, but the respective states are unknown. In the following description, the ARP status field is set to at least four statuses of “abnormal”, “normal”, and “status checking” in addition to no ARP status information.

The packet analysis unit 110 analyzes the ARP packet transferred from the switches 200A and 200B according to the flow entry of FIG. 4, and updates the ARP status information (apparatus status information). Specifically, the packet analysis unit 110 updates the ARP status information (apparatus status information) held in the packet information recording unit 120 based on the combination of the source and the destination of the ARP packet and the contents thereof.

FIG. 6 is a diagram showing an example of a transition table that the packet analysis unit 110 refers to when updating the ARP status information. For example, when the packet analysis unit 110 receives an ARP Request packet whose source IP address (hereinafter, source) is IP address X and destination IP address (hereinafter, destination) is other than X, the type is Request, and the transmission is An entry whose source is X and destination is other than X is selected. Then, the packet analysis unit 110 updates the ARP status information according to the content of the ARP status field of the terminal having the IP address X. For example, as shown in FIG. 5, when the ARP status information of the terminal A is “no ARP status information”, the packet analysis unit 110 changes the ARP status information of the terminal A from “no ARP status information” to “normal”. change. This means that the terminal A has determined that it is functioning normally because it has transmitted the ARP Request packet.

Further, for example, when an ARP Request packet in which the transmission source is other than X and the transmission destination is X is received, the packet analysis unit 110 selects an entry in which the type is Request, the transmission source is other than X, and the transmission destination is X. For example, as shown in FIG. 5, when the ARP status information of the terminal A is “no ARP status information”, the packet analysis unit 110 changes the ARP status information of the terminal A from “no ARP status information” to “during status confirmation”. Change to ". This detects that the ARP Request packet is transmitted to the terminal A, but the state of the terminal A cannot be known only by this. This means that the state of checking the state of the terminal A is changed depending on the presence or absence of the response from the terminal A.

It should be noted that (*1) in FIG. 6 means that a conditional change is performed such that the state is changed when a certain time has elapsed from the ARP state last update time in FIG. For example, when an ARP Request packet with a transmission source other than X and a transmission destination X is received, the packet analysis unit 110 determines that the state of the terminal or the like having the corresponding IP address is “abnormal” or “normal” and the ARP state is When a certain period of time has passed since the last update time, the status is changed to "Checking status". On the other hand, even if the status of the terminal or the like of the corresponding IP address is “abnormal” or “normal”, if the fixed time has not elapsed since the ARP status last update time, the packet analysis unit 110 maintains “status checking”. Will be done. This is "abnormal" or "normal", and if a certain time has not passed from the last update time, even if an ARP Request packet is sent from another terminal, the state of terminal A It cannot be said that it has changed. Therefore, the packet analysis unit 110 maintains the previous state. On the other hand, when the fixed time has elapsed, the packet analysis unit 110 uses the ARP Request packet sent from another terminal as a trigger, and the packet analysis unit 110 displays the ARP status information of the terminal or the like of the corresponding IP address. Change to "Checking status". As a result, the packet analysis unit 110 reviews the state of the terminal A according to the behavior of the terminal A.

Further, for example, when the packet analysis unit 110 receives an ARP Reply packet in which the transmission source is X and the transmission destination is other than the terminal X, the packet analysis unit 110 selects entries whose type is Reply, transmission source is X, and transmission destination is other than X. Then, the packet analysis unit 110 updates the ARP status information according to the content of the ARP status field of the terminal or the like having the corresponding IP address. For example, as shown in FIG. 5, when the ARP status information of the terminal A is “no ARP status information”, the packet analysis unit 110 changes the ARP status information of the terminal A from “no ARP status information” to “normal”. change. This means that the terminal A has determined that it is functioning normally because it has transmitted the ARP Reply packet.

Further, for example, when an ARP Reply packet in which the transmission source is other than X and the transmission destination is X is received, the packet analysis unit 110 selects an entry in which the type is Reply, the transmission source is other than X, and the transmission destination is X. In this case, the packet analysis unit 110 maintains the ARP status information of the terminal A in the previous status.

The recorded information analysis unit 130 updates the ARP status information held in the packet information recording unit 120 based on the elapsed time from the last updated time.

FIG. 7 is a diagram showing an example of a transition table that the recorded information analysis unit 130 refers to when updating the ARP status information. For example, the recorded information analysis unit 130 maintains the previous ARP status information when the ARP status information has not changed, except when the status is being confirmed. Further, when the status of the corresponding terminal or the like is being checked and a certain period of time has passed, the recorded information analysis unit 130 changes the ARP status information to “abnormal”. This corresponds to the operation of changing X, which is the transmission destination of the ARP Request packet, to “state checking” and then changing to “abnormal” when a certain period of time has elapsed.

Further, when no packet having the source of the corresponding IP address is received for a certain time or more, the recording information analysis unit 130 changes the ARP status information to “abnormal” except when there is no ARP status information. This corresponds to the communication from the terminal A being interrupted after the status of the corresponding terminal (for example, the terminal A) is determined to be “abnormal”, “normal”, or “state checking” according to the communication content. The recording information analysis unit 130 determines that it is “abnormal”.

The device status information providing unit 140 provides the ARP status information (device status information) held in the packet information recording unit 120 in response to an inquiry from the user. For example, when the device status information providing unit 140 receives an inquiry about the device status in which the IP address of the terminal A is designated, it refers to the ARP status information (device status information) in FIG. 5 and replies “No ARP status information”. To do.

Therefore, the packet receiving function of the packet analysis unit 110 of this embodiment corresponds to the packet reception unit, and the packet analysis unit 110 and the recorded information analysis unit 130 correspond to the device state management unit.

Next, the operation of this embodiment will be described in detail with reference to the drawings. In the following description, it is assumed that the flow entries shown in FIG. 4 are set in the switch 200A and the switch 200B, and that the terminal A transmits an ARP packet when starting communication with the terminal B. FIG. 8 is an activity diagram showing the operation of the first exemplary embodiment of the present invention. Referring to FIG. 8, first, when the terminal A transmits an ARP request (step S1), the switch 200A transfers the ARP request to the terminal B (step S2). Further, the switch 200A transfers the ARP request received from the terminal A to the packet analysis unit 110 of the device status management device 100 according to the flow entry shown in FIG. 4 (step S3).

The packet analysis unit 110 analyzes the ARP request transferred from the switch 200A (step S4). Specifically, the packet analysis unit 110 extracts the source IP address (IP address of the terminal A) and the destination IP address (IP address of the terminal B) from the ARP request, and executes the following processing.

First, the packet analysis unit 110 queries the packet information recording unit 120 for ARP status information (device status information) associated with an IP address that matches the IP address of the terminal A extracted from the ARP request (step S5). ).

At this point, the ARP status information (apparatus status information) of the terminal A is “no ARP status information” (unregistered) as shown in FIG. 5, so the packet information recording unit 120 indicates “no ARP status information”. Respond (step S6).

The packet analysis unit 110 that has received the response “no ARP status information” creates ARP status information of the terminal A (step S7). Specifically, the packet analysis unit 110 selects from the transition table of FIG. 6 an entry other than the type=Request, the source IP address=X, and the destination IP address X that meet the ARP conditions. Then, according to the condition “no ARP status information” of the entry, the packet analysis unit 110 creates ARP status information in which the ARP status is “normal”. Then, the packet analysis unit 110 instructs the packet information recording unit 120 to create the ARP status information of the terminal A whose ARP status is “normal”.

According to the instruction from the packet analysis unit 110, the packet information recording unit 120 creates ARP status information of the terminal A whose ARP status is “normal” (step S8).

In parallel with the analysis of the source IP address (IP address of terminal A), the packet analysis unit 110 analyzes the destination IP address (IP address of terminal B). The packet analysis unit 110 queries the packet information recording unit 120 for ARP status information (apparatus status information) associated with an IP address that matches the IP address of the terminal B extracted from the ARP request (step S9).

At this point in time, the ARP status information (device status information) of terminal B is “no ARP status information” (unregistered) as shown in FIG. 5, so the packet information recording unit 120 indicates “no ARP status information”. Respond (step S10).

The packet analysis unit 110 that has received the response “no ARP status information” creates ARP status information of the terminal B (step S11). Specifically, the packet analysis unit 110 selects an entry that matches the ARP condition of the destination IP address X other than the type=Request and the source IP address=X from the transition table of FIG. Then, according to the condition “no ARP status information” of the entry, the packet analysis unit 110 creates ARP status information in which the ARP status is “status checking”. Then, the packet analysis unit 110 instructs the packet information recording unit 120 to create the ARP status information of the terminal B whose ARP status is “status checking”.

According to the instruction from the packet analysis unit 110, the packet information recording unit 120 creates the ARP state information of the terminal B whose ARP state is “state checking” (step S12). As a result, the ARP status information of the terminal A and the terminal B in the packet information recording unit 120 is as shown in FIG. After that, when the device status information providing unit 140 receives an inquiry about the device status in which the IP address of the terminal A is designated, it refers to the ARP status information (device status information) in FIG. 9 and responds as “normal”. On the other hand, when receiving the inquiry about the device state in which the IP address of the terminal B is designated, the device state information providing unit 140 refers to the ARP state information (device state information) of FIG. .. In FIG. 9, the ARP state last update time is the ARP request reception time, but the time when the packet information recording unit 120 actually updated may be recorded.

After that, when the terminal B transmits the ARP response to the ARP request to the terminal A (step S21), the switch 200A transfers the ARP response to the terminal A (step S22). Further, the switch 200A transfers the ARP response received from the terminal B to the packet analysis unit 110 of the device status management device 100 according to the flow entry shown in FIG. 4 (step S23).

The packet analysis unit 110 analyzes the ARP response transferred from the switch 200A (step S24). Specifically, the packet analysis unit 110 extracts the source IP address (IP address of the terminal B) and the destination IP address (IP address of the terminal A) from the ARP response, and executes the following processing.

First, the packet analysis unit 110 queries the packet information recording unit 120 for ARP status information (device status information) associated with an IP address that matches the IP address of the terminal B extracted from the ARP response (step S25). ).

Since the ARP status information (apparatus status information) of the terminal B is “status checking” as shown in FIG. 9, the packet information recording unit 120 responds “status checking” (step S26).

The packet analysis unit 110, which has received the response of "status confirmation", confirms the ARP status information of the terminal B (step S27). Specifically, the packet analysis unit 110 follows the condition “state checking” of the entry that matches the ARP conditions other than the type=Reply, the source IP address=X, and the destination IP address X from the transition table of FIG. The necessity of updating the ARP status information of the terminal A is confirmed. Then, the packet analysis unit 110 instructs the packet information recording unit 120 to change the ARP status of the ARP status information of the terminal B to “normal”.

The packet information recording unit 120 updates the ARP status of the ARP status information of the terminal B to “normal” according to the instruction from the packet analysis unit 110 (step S28).

In parallel with the analysis of the source IP address (IP address of the terminal B), the packet analysis unit 110 analyzes the destination IP address (IP address of the terminal A). The packet analysis unit 110 queries the packet information recording unit 120 for ARP status information (apparatus status information) associated with an IP address that matches the IP address of the terminal A extracted from the ARP response (step S29).

Since the ARP status information (apparatus status information) of the terminal A is "normal" as shown in FIG. 9, the packet information recording unit 120 responds "normal" (step S30).

The packet analysis unit 110, which has received the response "normal", confirms whether the ARP status information of the terminal A is appropriate (step S31). Specifically, the packet analysis unit 110 follows the condition “normal” of the entry that matches the ARP condition other than the type=Reply, the source IP address=X, and the destination IP address X from the transition table of FIG. Make sure that no changes are required.

As a result, the ARP status information of the terminal A and the terminal B in the packet information recording unit 120 is as shown in FIG. After that, when the device status information providing unit 140 receives an inquiry about the device status in which the IP addresses of the terminals A and B are specified, it refers to the ARP status information (device status information) in FIG. respond. In FIG. 10, the ARP state last update time is the ARP request reception time and the ARP response reception time, but the time at which the packet information recording unit 120 actually updated may be recorded.

In the above description using FIG. 8, the terminal B has been described as transmitting the ARP response, but if the terminal B does not exist or is out of order, the terminal B does not transmit the ARP response. Therefore, the ARP status of the ARP status information of the terminal B remains "state checking". Hereinafter, the operation of updating the ARP status information by the recording information analysis unit 130 will be described.

FIG. 11 is an activity diagram showing an updating operation of the ARP status information (device status information) of the recorded information analysis unit 130 of the device status management device according to the first embodiment of the present invention. Referring to FIG. 11, first, the record information analysis unit 130 inquires of the packet information recording unit 120 about the ARP status information of the terminal B (step S41). Note that the record information analysis unit 130 may start the process of FIG. 11 with the elapse of a predetermined time from the previous update operation. Alternatively, the processing of FIG. 11 may be started when the packet information recording unit 120 notifies that there is an entry that has passed a certain period of time since the ARP state last update time.

The packet information recording unit 120, which receives the inquiry from the recording information analysis unit 130, responds to the recording information analysis unit 130 with the ARP status information of the terminal B whose ARP status is still “status confirmation” (step). S42).

The recorded information analysis unit 130 confirms whether or not a fixed time has passed from the last update time of the ARP status information of the terminal B received from the packet information recording unit 120 (step S43). Here, when the fixed time has not passed from the last update time of the ARP status information of the terminal B, the recorded information analysis unit 130 does not update the ARP status information of the terminal B (step S44).

On the other hand, when a certain period of time has passed from the last update time of the ARP status information of the terminal B, the recording information analysis unit 130 refers to the table of FIG. 7 and sets the ARP status of the ARP status information of the terminal B to “abnormal”. Is updated (step S45). Specifically, the recorded information analysis unit 130 sets the ARP status of the ARP status information of the terminal B to “abnormal” according to the setting content of “status checking” of the entry in which the ARP status remains unchanged for a certain period of time in the table of FIG. 7. The packet information recording unit 120 is instructed to change to

The packet information recording unit 120 updates the ARP status of the ARP status information of the terminal B to “abnormal” according to the instruction from the recording information analysis unit 130 (step S46).

As a result, the ARP status information of the terminal A and the terminal B in the packet information recording unit 120 becomes as shown in FIG. After that, when the device status information providing unit 140 receives an inquiry about the device status in which the IP address of the terminal A is specified, it refers to the ARP status information (device status information) in FIG. 12 and replies “normal”. On the other hand, when a device state inquiry specifying the IP address of the terminal B is received thereafter, the device state information providing unit 140 refers to the ARP state information (device state information) of FIG. 12 and replies “abnormal”. .. As described above, according to the present embodiment, it is possible to recognize the abnormality of the device without transmitting/receiving a special packet. Note that, in FIG. 12, the ARP status last update time uses the ARP request reception time and the ARP response reception time, but even when the packet information recording unit 120 actually records the update time, respectively. Good.

In the description using FIG. 11, the terminal B is determined to be “abnormal”, but thereafter, the terminal B may be able to normally communicate. The operation of updating the ARP status information by the packet analysis unit 110 will be described below.

FIG. 13 is an activity diagram showing an updating operation of ARP status information (device status information) by the packet analysis unit of the device status management device according to the first embodiment of the present invention. Referring to FIG. 13, first, the packet analysis unit 110 inquires of the packet information recording unit 120 about the ARP status information of the terminal B (step S51). Note that the timing at which the packet analysis unit 110 starts the processing in FIG. 13 is assumed to be the timing at which the ARP packet addressed to the terminal B is received from the terminal A. Therefore, the apparatus state management apparatus 100 may perform the processing of steps S5 to S8 of FIG. 8 in parallel with the processing of FIG.

At this point, the ARP status information (device status information) of the terminal B is “abnormal” as shown in FIG. 12, so the packet information recording unit 120 informs the packet analysis unit 110 that the APR status is “abnormal”. Responding with the ARP status information that has become (step S52).

Upon receiving the ARP status information, the packet analysis unit 110 refers to the ARP status last update time and confirms whether or not a fixed time has elapsed from the last update time of the ARP status information (step S53). Here, when the fixed time has not elapsed from the ARP state last update time, the packet analysis unit 110 confirms whether the ARP state of the ARP state information is “normal” or “abnormal” (step S54). ). Here, when the ARP status is either “normal” or “abnormal”, the packet analysis unit 110 maintains (does not update) the ARP status of the ARP status information of the terminal B (step S55).

On the other hand, when the fixed time has passed since the last update time of the ARP status information (Yes in step S53), or when the ARP status is other than “normal” or “abnormal”, the packet analysis unit 110 Updates the ARP status information of terminal B (step S56). Specifically, the packet analysis unit 110 refers to the transition table of FIG. 6 and confirms whether or not the ARP state of the terminal B needs to be changed. When it is determined that the ARP state of the terminal B is changed as a result of the confirmation, the packet analysis unit 110 instructs the packet information recording unit 120 to update the ARP state information of the terminal B. For example, when the ARP request addressed to the terminal B is received, the entries of the source IP address=X other than the type=Request and the source IP address=X of the transition table of FIG. 6 are referred to. In this case, the packet analysis unit 110 determines to change the ARP status of the terminal B to “status confirmation”.

The packet information recording unit 120 updates (changes) the ARP status of the ARP status information of the terminal B according to the instruction from the recording information analysis unit 130 (step S57).

As described above, according to the present embodiment, even when it is once determined to be “normal” or “abnormal”, the reception of the ARP packet may trigger the elapse of a certain period of time or the “ARP status information”. In the case of "none", the status will be changed to "status confirmation". This makes it possible to grasp the latest state of the terminal and the like and provide it to the user as necessary.

As described above, according to the present embodiment, it is possible to grasp the latest state of the terminal or its communication partner by using the ARP packet that the terminal always sends at the start of communication. In other words, it can be said that the present embodiment has the following various effects.
1. Even if the target IP address is not known in advance, the device can be monitored in the same manner as the NMS.
2. Unlike Patent Document 1, it is not necessary to send a special packet for the purpose of monitoring.
3. Since the information is stored in the packet information recording unit, the status can be confirmed by a terminal that has communicated even once.

Although the respective embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and further modifications, replacements, and adjustments can be made without departing from the basic technical idea of the present invention. Can be added. For example, the network configuration, the configuration of each element, the expression form such as a table shown in each drawing are examples for helping understanding of the present invention, and are not limited to the configurations shown in these drawings. For example, in the above-described embodiment, the description has been made assuming that OpenFlow is used to transfer the ARP packet to the switch, but it is not particularly limited as long as the switch can select the ARP packet and transfer it to the device state management device. ..

Further, in the above-described embodiment, the ARP packet is used as the packet of the address resolution protocol, but the address resolution protocol is not limited to ARP in a narrow sense. For example, in IPv6, the ND (Neighbor Discovery) protocol is used for address resolution. In this case as well, by setting a flow entry for transferring a packet of the ND protocol to the device state management device 100 in the switches 200A and 200B, it is possible to similarly grasp the device state.

Further, the procedure described in the above embodiment can be realized by a program that causes a computer (9000 in FIG. 15) functioning as the device status management device 100 to realize the function as the device status management device 100. Such a computer is exemplified by the configuration including the CPU (Central Processing Unit) 9010, the communication interface 9020, the memory 9030, and the auxiliary storage device 9040 in FIG. That is, the CPU 9010 of FIG. 15 may execute the packet analysis program and the recording information analysis program to update the respective calculation parameters held in the auxiliary storage device 9040 or the like.

That is, each unit (processing unit, function) of the apparatus state management apparatus 100 shown in the above-described embodiment is executed by a computer program that causes a processor mounted in the apparatus to execute the above-described processing using its hardware. Can be realized.

Finally, the preferred forms of the invention are summarized.
[First form]
(Refer to the device state management device from the first viewpoint)
[Second mode]
The device status management device described above further includes
It is preferable that the switch has a function of setting control information (flow entry) for transferring a packet of an address resolution protocol between the devices to a predetermined device status confirmation device.
[Third form]
The device status management device described above further includes
It is preferable that the apparatus further comprises a packet information recording unit that records a state of the device based on an exchange state of packets of the address resolution protocol between the devices.
[Fourth form]
The device status management device described above further includes
A packet information analysis unit is provided, which refers to the packet information recording unit and determines that the destination of the address resolution protocol packet is abnormal when a response to the address resolution protocol packet cannot be received within a predetermined time. Is preferred.
[Fifth form]
The device status management unit of the device status management device described above,
When the address resolution request packet of the address resolution protocol is received, the destination of the address resolution request packet may be managed as the status checking state.
[Sixth form]
(Refer to the method of managing the state of the device from the above second viewpoint)
[Seventh form]
(See the program from the third viewpoint above)
The sixth to seventh forms can be expanded to the second to fifth forms, like the first form.

The disclosures of the above-mentioned patent documents and non-patent documents are incorporated herein by reference. Modifications and adjustments of the exemplary embodiments and examples are possible within the scope of the overall disclosure (including claims) of the present invention and based on the basic technical concept of the invention. Further, within the framework of the disclosure of the present invention, various combinations or selections (parts) of various disclosed elements (including each element of each claim, each element of each embodiment or example, each element of each drawing, etc.) (Including targeted deletion) is possible. That is, it goes without saying that the present invention includes various variations and modifications that can be made by those skilled in the art according to the entire disclosure including the claims and the technical idea. In particular, with regard to the numerical range described in this specification, any numerical value or small range included in the range should be construed as specifically described even if not otherwise specified.

10, 100 Device status management device 11 Packet reception unit 12 Device status management unit 20, 200A, 200B Switch 110 Packet analysis unit 120 Packet information recording unit 130 Record information analysis unit 140 Device status information provision unit 9000 Computer 9010 CPU
9020 Communication interface 9030 Memory 9040 Auxiliary storage device

Claims (10)

A packet receiving unit that receives the packet of the address resolution protocol from a switch that operates according to control information that causes a packet of the address resolution protocol between devices to be transferred to a predetermined device status confirmation device;
A device state management unit that manages the states of the source and destination devices of the address resolution protocol packet based on the state of transmission and reception of the address resolution protocol packet between the devices;
A device state management device including. The switch has a function of setting control information for transferring a packet of an address resolution protocol between the devices to a predetermined device status confirmation device,
The device status management device according to claim 1. further,
A packet information recording unit for recording the state of the device based on the exchanged state of packets of the address resolution protocol between the devices,
The device state management device according to claim 1 or 2. further,
The packet information recording unit is referred to, and if a response to the packet of the address resolution protocol cannot be received within a predetermined time, a recording information analysis unit that determines that the destination of the packet of the address resolution protocol is abnormal is provided.
The device status management device according to claim 3. The device status management unit,
5. The device status management device according to claim 1, wherein, when an address resolution request packet of the address resolution protocol is received, a destination of the address resolution request packet is managed as a status checking state. Receive a packet of the address resolution protocol from a switch that operates according to control information that causes a packet of the address resolution protocol between devices to be transferred to a predetermined device status confirmation device,
Managing the state of the source and destination devices of the address resolution protocol packet based on the state of transmission and reception of the address resolution protocol packet between the devices;
How to manage the state of the device. In the switch, set control information for transferring a packet of an address resolution protocol between the devices to a predetermined device status confirmation device,
The method for managing the state of the device according to claim 6. Furthermore, the state of transmission and reception of the packet of the address resolution protocol between the devices is recorded,
A method for managing the state of a device according to claim 6 or 7. If the response to the packet of the address resolution protocol cannot be received within a predetermined time based on the transfer status of the recorded packet, it is determined that the destination of the packet of the address resolution protocol is abnormal.
The method for managing the state of the device according to claim 8. A process of receiving a packet of the address resolution protocol from a switch that operates according to control information for transferring a packet of the address resolution protocol between devices to a predetermined device status confirmation device;
A process of managing the states of the source and destination devices of the address resolution protocol packet based on the state of transmission and reception of the address resolution protocol packet between the devices;
A program that causes a computer to execute.

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