JP2019176354A - Control device, arp response equipment, communication system, and synchronization method - Google Patents

Abstract

To reduce a communication load at synchronization of ARP information in proportion to an information amount of ARP information to be synchronized.SOLUTION: A communication system includes: response equipment 10 which holds a plurality of address solution information sets to respond to an address solution request using the plurality of address solution information sets; and a controller 20 which is communicable with the response equipment and controls switches 30, 31 on the network. The response equipment, when holding new address solution information, transmits the new address solution information to the controller. When receiving the new address solution information, the controller determines whether or not to synchronize address solution information with the response equipment, on the basis of a first time when the new address solution information is generated and a second time when address solution information received immediately before the above reception. When determining to perform synchronization, the controller synchronizes the address solution information held by the response equipment during a time interval from the second time to the first time with the controller.SELECTED DRAWING: Figure 1

Description

The present invention relates to a controller, an ARP response device, a system including a controller and an ARP response device, and a method of synchronizing ARP information in the system, for executing synchronization of ARP (Address Resolution Protocol) information.

  In recent years, SDN (Software Defined Network) has been attracting attention as the network becomes larger and more complicated.

  One technique for realizing SDN is OpenFlow described in Non-Patent Document 1. In a network to which an SDN technology such as OpenFlow is applied, a control device (hereinafter referred to as a controller) centrally controls a plurality of communication devices (hereinafter referred to as switches) that perform packet transfer. Thereby, control and management of a network can be performed easily.

  As an example of an ARP (Address Resolution Protocol) process that is a destination resolution process in a network to which the SDN technology is applied, there is a technique for causing a controller to execute an ARP response.

  In this case, the switch that has received the ARP request from the communication source terminal transmits the received ARP request to the controller without broadcasting.

  When the controller receives an ARP request from the switch, the controller stores a table storing information (hereinafter referred to as ARP information) in which IP (Internet Protocol) addresses and MAC (Media Access Control) addresses stored in advance are associated with each other. The MAC address corresponding to the requested IP address is identified.

  Further, after specifying the MAC address, the controller generates an ARP response including the MAC address and transmits it to the communication source terminal. By performing such processing, the communication source terminal can specify the MAC address of the communication partner.

  As described above, when the controller makes an ARP response, the ARP processing can be performed without broadcast communication of the ARP request as in the conventional case, so that the compression of the communication band can be reduced.

  On the other hand, since ARP requests are concentrated on the controller, there is a problem that the ARP processing cannot be performed when a failure of the controller or a failure occurs in communication between the controller and the switch.

There exists patent document 1 as a method of solving the said problem. Patent Document 1 discloses a communication system including a multi-active gateway that can perform an ARP response instead of a controller. According to the communication system of Patent Document 1, the multi-active gateway holds the same ARP information as the controller, and can use the ARP information to make an ARP response instead of the controller. Furthermore, it is disclosed that when the multi-active gateway fails, the controller synchronizes the ARP information held by the controller and the multi-active gateway by transmitting all the ARP information held by the controller to the multi-active gateway.

JP 2017-028698

ONF (Open Networking Foundation), “OpenFlow Switch Specification, Version 1.5.1 (Protocol version 0x06),” March 26, 2015. [URL search on January 26, 2018] t //www.opennetworking.org/images/stories/downloads/sdn-resources/onf-specifications/openflow/openflow-switch-v1.5.1. pdf>

  The following analysis has been made according to the present invention. In Patent Literature 1, when ARP information synchronization is executed, all ARP information held by the controller is transmitted to the multi-active gateway. Therefore, the communication load when synchronizing ARP information increases in proportion to the information amount of ARP information to be synchronized.

The present invention has been made in view of the above problems, and an object thereof is to reduce a communication load when executing synchronization of ARP information.

  According to the first aspect of the present invention, a response device that holds a plurality of address resolution information and responds to an address resolution request using the plurality of address resolution information, and can communicate with the response device. A controller that controls the upper switch, and the responding device transmits the new address resolution information to the controller when the new address resolution information is held, and the controller receives the new address resolution information In addition, the response device and the address resolution information are synchronized based on the first time when the new address resolution information is generated and the second time when the address resolution information received immediately before the reception is generated. If the response device determines that synchronization is to be performed, the address resolution information held by the responding device between the second time and the first time is the same as that of the controller. Communication system, characterized in that it is provided.

  According to a second aspect of the present invention, a storage unit that holds address resolution information, a storage unit that stores the received address resolution information in the storage unit, and the address resolution when the storage unit receives the address resolution information. Whether to synchronize the response device with the address resolution information based on the first time when the information is generated and the second time when the address resolution information received immediately before the reception is generated And a synchronization request unit that requests synchronization of address resolution information generated between the second time and the first time when the determination unit determines to perform synchronization. A controller is provided.

  According to the third aspect of the present invention, a response device that holds a plurality of address resolution information and responds to an address resolution request using the plurality of address resolution information can communicate with the response device. A method of synchronizing address resolution information performed by a communication system including a controller that controls the upper switch, and when the responding device holds new address resolution information, transmits the address resolution information to the controller A first time when the address resolution information is generated when the controller receives the address resolution information, and a second time when the address resolution information received immediately before the reception is generated And determining whether to synchronize the address resolution information with the responding device, and if the controller determines to synchronize Response equipment synchronization method address resolution information, which comprises the steps of: synchronizing with the controller the held address resolution information between the first time from the second time, is provided.

According to the fourth aspect of the present invention, when new address resolution information is received by a computer that controls a switch on the network and holds the address resolution information, the first address resolution information is generated. And whether or not to synchronize the address resolution information with the responding device that responds to the address resolution request based on the time of the first time and the second time when the address resolution information received immediately before the reception is generated And a process for requesting synchronization of address resolution information generated between the second time and the first time when it is determined that synchronization is performed. Is provided.

  According to the present invention, the controller specifies a time zone to be synchronized, and the ARP response device synchronizes only the address resolution information generated in the specified time zone with the controller.

  Thereby, the information amount of the address resolution information which an ARP response apparatus transmits to a controller can be reduced.

Therefore, it is possible to reduce the communication load when synchronizing the address resolution information.

It is a figure which shows the structure of the communication system concerning this invention. It is a figure which shows the structure of the ARP response apparatus in 1st Embodiment. It is a figure which shows an example of the mapping information which the ARP response apparatus in 1st Embodiment hold | maintains. It is a figure which shows the structure of the controller in 1st Embodiment. It is a figure which shows an example of the mapping information which the controller in 1st Embodiment hold | maintains. It is a flowchart which shows the processing operation | movement of the ARP response when the ARP response apparatus in 1st Embodiment receives an ARP request. It is a flowchart which shows the synchronization necessity determination processing operation | movement of the mapping information performed when the controller in 1st Embodiment receives mapping information from an ARP response apparatus. It is a figure which shows an example of the mapping information hold | maintained when the controller in 1st Embodiment performs a synchronization necessity determination processing operation. It is a flowchart which shows the processing operation when the ARP response apparatus in 1st Embodiment receives the synchronous request | requirement from a controller. It is a figure which shows an example of the mapping information which the ARP response apparatus in 1st Embodiment extracted. It is a figure which shows that the mapping information which a controller hold | maintains in 1st Embodiment, and the mapping information which an ARP response apparatus hold | maintains are synchronizing. It is a figure which shows the structure of the ARP response apparatus in 2nd Embodiment. It is a flowchart which shows the synchronous processing operation | movement of the mapping information when the ARP response apparatus in 2nd Embodiment receives the synchronous request | requirement from a controller. It is a figure which shows an example in which the ARP response apparatus in 2nd Embodiment divides | segments mapping information.

[First Embodiment]
A first embodiment of the present invention will be described in detail with reference to FIG.

[Description of configuration]
FIG. 1 is a diagram showing a configuration of a communication system according to the present invention.

  The communication system in FIG. 1 includes an ARP response device 10, a controller 20, a switch 30, a switch 31, a terminal 40, and a terminal 41.

  The controller 20 is connected to the ARP response device 10, the switch 30, and the switch 31.

  The switch 30 is connected to the ARP response device 10, the switch 31, and the terminal 40, respectively.

  The switch 31 is connected to the terminal 41.

  The controller 20 and the response device 10, the controller 20 and the switch 30, and the controller 20 and the switch 31 are respectively connected by a dedicated line for control, and the connection relationship is indicated by a broken line in FIG. The dedicated line for control is, for example, an OpenFlow channel.

  The response device 10 and the switch 30, and the switch 30 and the switch 31 are connected by a normal data line, and the connection relationship is shown by a solid line in FIG.

  The switch 30 and the switch 31 are communication devices that process received packets. For example, the switch 30 and the switch 31 are OpenFlow switches.

  The terminal 40 and the terminal 41 are communication terminals such as a mobile phone terminal, a smartphone, a tablet, and a PC (Personal Computer).

  FIG. 2 is a diagram illustrating a configuration of the ARP response device 10.

  The ARP response device 10 includes a communication unit 11, a storage unit 12, a response processing unit 13, and a synchronization processing unit 14.

  The communication unit 11 is a communication interface for performing communication with the controller 20 and the switch 30.

  The storage unit 12 holds information in which ARP information for responding to an ARP request is associated with time information indicating the time when the ARP information is generated (hereinafter, this information is referred to as mapping information).

  FIG. 3 shows an example of mapping information held by the storage unit 12. The mapping information is managed in a table as shown in FIG.

  For example, the MAC address of the terminal to which the IP address “192.168.196.0” is assigned is “FF: FF: FF: FF: FF: 0”, and ARP information in association with these is generated. It is shown that the set time is “10:00”.

  The response processing unit 13 refers to the storage unit 12 and specifies the MAC address corresponding to the IP address requested by the ARP request.

  When receiving the mapping information synchronization request from the controller 20, the synchronization processing unit 14 refers to the storage unit 12 and specifies mapping information to be synchronized with the controller 20.

  FIG. 4 is a diagram illustrating a configuration of the controller 20.

  The controller 20 includes a communication unit 21, a switch control unit 22, a storage unit 23, a storage unit 24, a determination unit 25, and a synchronization request unit 26.

  The communication unit 21 is a communication interface for performing communication with the ARP response device 10, the switch 30, and the switch 31.

  The switch control unit 22 controls the switch 30 and the switch 31. Specifically, the switch control unit 22 generates control information for the switch 30 and the switch 31 to process the received packet. Further, the switch control unit 22 transmits the generated control information to the switch 30 and the switch 31.

  The accumulation unit 23 stores the received mapping information in the storage unit 24.

  The storage unit 24 holds mapping information. Since the mapping information is the same quality as the mapping information held by the storage unit 12, detailed description thereof is omitted.

  FIG. 5 shows an example of mapping information held by the storage unit 24. The mapping information held by the storage unit 24 is managed in the same manner as the mapping information held by the storage unit 12.

  The determination unit 25 refers to the storage unit 24 and determines whether or not to request the synchronization of the mapping information from the time information included in the mapping information.

The synchronization request unit 26 requests the synchronization of mapping information.

[Description of operation]
The operation of the communication system of this embodiment will be described.

  In the following, a case where the terminal 40 makes an ARP request for address resolution of the terminal 41 will be described.

  The terminal 40 transmits an ARP request for requesting the MAC address of the terminal 41 including the IP address of the terminal 41 to the switch 30.

  The switch 30 transmits the received ARP request to the ARP response device 10 and the controller 20.

  The ARP response device 10 makes an ARP response to the received ARP request.

  As a result of the ARP response, when the mapping information held in the storage unit 12 is updated, the ARP response device 10 transmits the updated mapping information to the controller 20.

  When receiving the mapping information from the ARP responding device 10, the controller 20 determines whether or not the mapping information needs to be synchronized from the time information included in the mapping information and the time information included in the mapping information received immediately before. to decide.

  When the controller 20 determines that the synchronization of the mapping information is necessary, the controller 20 generates a synchronization request including information indicating a time zone in which synchronization is required (hereinafter, this information is described as time zone information). Transmit to the ARP response device 10.

  When receiving the synchronization request from the controller 20, the ARP response device 10 extracts the mapping information generated in the time zone corresponding to the time zone information and transmits it to the controller 20.

  When receiving the mapping information extracted by the ARP response device 10, the controller 20 stores the difference from the mapping information held in the storage unit 24.

  In this way, the mapping information is synchronized between the ARP responding device 10 and the controller 20.

  FIG. 6 is a flowchart showing an ARP response processing operation when the ARP response device 10 receives an ARP request.

  When receiving the ARP request, the response processing unit 13 searches the storage unit 12 for mapping information including the IP address using the IP address of the terminal 41 included in the ARP request as a key (S61).

  If mapping information including the IP address as a key is found as a result of searching the storage unit 12 (Yes in S62), the response processing unit 13 creates a response packet including the MAC address included in the mapping information (S68). ), The response packet is transmitted to the terminal 40 (S69).

  On the other hand, as a result of searching the storage unit 12, if the MAC address corresponding to the key IP address is not found (No in S62), the response processing unit 13 acquires the MAC address corresponding to the key IP address. Therefore, an ARP request including the IP address is transmitted by broadcast (S63).

  The response processing unit 13 receives a response packet including a MAC address corresponding to the IP address from the terminal 41 having the key IP address, and acquires the MAC address (S64).

  The response processing unit 13 creates ARP information by associating the acquired MAC address with the IP address included in the ARP request from the terminal 40 (S65).

  The response processing unit 13 stores the created ARP information in the storage unit 12.

  When storing the ARP information in the storage unit 12, the response processing unit 13 associates the ARP information with time information indicating the time at which the ARP information was generated, and stores it in the storage unit 12 as mapping information (S66).

  The response processing unit 13 transmits the mapping information including the acquired MAC address to the controller 20 (S67), creates a response packet including the MAC address (S68), and transmits the response packet to the terminal 40 (S69).

  In the above description, the response processing unit 13 generates the response packet after transmitting the mapping information to the controller 20, and transmits the response packet to the terminal 40. However, the response processing unit 13 generates the response packet, and the terminal After transmitting to 40, the mapping information may be transmitted to the controller 20, or these processing operations may be performed in parallel.

  Through the series of processes described above, the ARP response device 10 makes an ARP response to the received ARP request.

  FIG. 7 is a flowchart showing the mapping information synchronization necessity determination processing operation performed by the controller 20 when mapping information is received from the ARP response device 10. Here, a case where the mapping information held by the storage unit 24 is as shown in FIG. 8 will be described as an example.

  That is, the received mapping information is mapping information 8A including time information “10:06”, and the mapping information received immediately before is mapping information 8B including time information “10:01”.

  When receiving the mapping information, the storage unit 23 stores the mapping information in the storage unit 24 (S71).

  When the mapping information is stored in the storage unit 24, the determination unit 25 refers to the storage unit 24, the time indicated by the time information included in the mapping information 8A, and the mapping information 8B received immediately before the mapping information 8A. It is determined whether or not the time interval with the time indicated by the time information included in is greater than or equal to a threshold value, and based on the result, it is determined whether or not the mapping information needs to be synchronized.

  The threshold value is preset by, for example, the administrator of the communication system.

  Here, the time information included in the mapping information 8A and 8B is “10:06” and “10:01”, respectively, and the time interval is 5 minutes.

  That is, the determination unit 25 determines whether synchronization is necessary based on whether the time interval of 5 minutes is equal to or greater than a threshold value.

  For example, when the threshold value is 3 minutes, the determination unit 25 needs to synchronize the mapping information held by the storage unit 12 and the mapping information held by the storage unit 24 because the time interval is equal to or greater than the threshold value. (Yes in S72).

  When the mapping information needs to be synchronized, the determination unit 25 indicates the time indicated by the time information included in the received mapping information and the time indicated by the time information included in the mapping information received immediately before the mapping information. Is set as a synchronization target time zone (S73).

  Therefore, in this case, since the time interval is equal to or greater than the threshold value, the determination unit 25 sets the time zone “10:01 to 10:06” as the time zone to be synchronized.

  The synchronization request unit 26 generates a synchronization request including time zone information indicating the set time zone (S74) and transmits it to the ARP response device 10 (S75).

  For example, in this case, since the time information included in the mapping information 8A and 8B is “10:06” and “10:01”, respectively, the synchronization request unit 26 sets the time from “10:01 to 10:06”. A synchronization request including time zone information indicating a zone is generated and transmitted to the response device 10.

  On the other hand, when the threshold value is 10 minutes, the determination unit 25 does not need to synchronize the mapping information held by the storage unit 12 and the mapping information held by the storage unit 24 because the time interval is less than the threshold value. (No in S72).

  The determination part 25 complete | finishes a process, when the synchronization of mapping information is unnecessary.

  The controller 20 waits until new mapping information is received.

  When the controller 20 newly receives the mapping information, the above processing is repeated.

  Through the series of processing operations described above, the controller 20 performs mapping information synchronization necessity determination processing.

  FIG. 9 is a flowchart showing the mapping information synchronization processing operation when the ARP response device 10 receives a synchronization request from the controller 20.

  The synchronization processing unit 14 searches the storage unit 12 for mapping information including time information indicating the time included in the time zone indicated by the time zone information, using the time zone information included in the synchronization request as a key (S91).

  For example, in the mapping information (see FIG. 3) held by the storage unit 12, the synchronization processing unit 14 indicates that the time indicated by the time information included in the mapping information is the time zone indicated by the time zone information included in the synchronization request. 10:01 to 10:06 ", it is determined that the mapping information is mapping information corresponding to the time zone.

  FIG. 10 is a diagram illustrating an example of the mapping information to be synchronized among the mapping information held by the storage unit 12. For example, in this case, the mapping information corresponding to the time zone “10:01 to 10:06” shown in FIG. 10 among the mapping information held by the storage unit 12 is the mapping information to be synchronized.

  If there is corresponding mapping information as a result of searching the storage unit 12 (Yes in S92), the synchronization processing unit 14 transmits the mapping information to the controller 20 (S93).

  For example, in this case, the synchronization processing unit 14 transmits the mapping information illustrated in FIG. 10 to the controller 20.

  When the controller 20 receives the mapping information from the ARP response device 10, the controller 20 compares the mapping information with the mapping information held by the own device, and whether the received mapping information and the mapping information held by the own device overlap. Determine whether or not.

  The controller 20 stores, in the storage unit 24, mapping information that does not overlap with mapping information held by the own device among the received mapping information.

  On the other hand, the controller 20 discards the mapping information that overlaps the mapping information held by the own device among the received mapping information.

  For example, the controller 20 already holds mapping information whose time information is “10:01” and mapping information whose time information is “10:06” (see FIG. 8). Then, the mapping information other than the time information “10:01” and “10:06” is stored in the storage unit 24.

  FIG. 11 is a diagram illustrating that the mapping information held by the controller 20 and the mapping information held by the ARP response device 10 are synchronized. FIG. 11A shows mapping information that the controller 20 holds before synchronization processing. FIG. 11B shows mapping information received from the ARP response device 10 by the controller 20 in the synchronization process. FIG. 11C shows mapping information that the controller 20 holds after the synchronization processing. The mapping information held by the controller 20 after the synchronization process (see FIG. 11C) is synchronized with the mapping information held by the ARP response device 10 (see FIG. 3).

  Thereby, the mapping information held by the controller 20 can be synchronized with the mapping information held by the ARP response device 10.

  On the other hand, if there is no corresponding mapping information as a result of searching the storage unit 12 (No in S92), the synchronization processing unit 14 notifies the controller 20 that synchronization is not required (S94).

By the series of processes described above, the synchronization process of the mapping information between the ARP response device 10 and the controller 20 is executed.

[effect]
In the communication system according to the first embodiment of the present invention, when the controller receives the mapping information from the ARP response device, the controller includes the time indicated by the time information included in the mapping information and the mapping information received immediately before. It is determined whether or not the time interval with the time indicated by the time information is equal to or greater than a threshold value, and based on the result, it is determined whether or not the mapping information needs to be synchronized. When it is determined that synchronization is necessary, the controller sends the time indicated by the time information included in the received mapping information to the ARP response device and the time indicated by the time information included in the mapping information received immediately before. And request synchronization of mapping information corresponding to the time zone between.

  Thereby, since the ARP response device transmits only the mapping information generated in the time zone set by the controller to the controller, the information amount of the mapping information transmitted to the controller can be reduced.

Therefore, it is possible to reduce the communication load when synchronizing the ARP information.


[Second Embodiment]
A communication system according to the second embodiment of the present invention will be described in detail with reference to the drawings.

[Description of configuration]
The communication system in the second embodiment and the communication system in the first embodiment are different in the configuration of the ARP response device. A specific difference is that the synchronization processing unit 140 of the ARP response device 100 according to the second embodiment includes an extraction unit 141 and a division unit 142.

  FIG. 12 is a diagram illustrating a configuration of the ARP response device 100 of the communication system according to the second embodiment. In addition, about the structure which performs the same processing operation as the structure of the ARP response apparatus 10 of 1st Embodiment among the structures of the ARP response apparatus 100, the same code | symbol as FIG. 2 is attached | subjected and detailed description is abbreviate | omitted.

  The synchronization processing unit 140 includes an extraction unit 141 and a division unit 142.

  The extraction unit 141 extracts mapping information corresponding to the time zone set by the controller 20 from the storage unit 12.

The dividing unit 142 determines whether to divide the extracted mapping information.

[Description of operation]
A processing operation of the communication system according to the second embodiment will be described.

  Hereinafter, as in the first embodiment, the processing operation of the communication system of the second embodiment when the terminal 40 makes an ARP request for address resolution of the terminal 41 will be described. Note that the ARP response processing operation of the ARP response device 100 and the mapping information synchronization necessity determination processing operation of the controller 20 in the second embodiment are the same as those in the first embodiment, and thus description thereof is omitted. .

  FIG. 13 is a flowchart illustrating a mapping information synchronization processing operation when the ARP response device 100 receives a synchronization request from the controller 20.

  When receiving the synchronization request from the controller 20, the extraction unit 141 searches the storage unit 12 for mapping information corresponding to the time zone indicated by the time zone information using the time zone information included in the synchronization request as a key (S131).

  For example, the extraction unit 141 uses the time zone information included in the synchronization request received from the controller 20 as the time indicated by the time information included in the mapping information among the mapping information held by the storage unit 12 (see FIG. 3). If it is included in the indicated time zone “10:01 to 10:06”, it is determined that the mapping information is mapping information corresponding to the time zone.

  If there is corresponding mapping information as a result of searching the storage unit 12 (Yes in S132), the extraction unit 141 extracts the mapping information from the storage unit 12.

  The dividing unit 142 determines whether or not the information amount of the extracted mapping information is equal to or greater than a predetermined information amount, and determines whether or not to divide the mapping information based on the result.

  The predetermined amount of information is set in advance by the administrator of the communication system, for example.

  Here, it is assumed that the information amount of the extracted mapping information is 2000 bytes.

  That is, the dividing unit 142 determines whether or not to divide the mapping information based on whether or not the information amount 2000 bytes of the extracted mapping information is greater than or equal to a predetermined information amount.

  For example, if the predetermined information amount is 1000 bytes, the dividing unit 142 determines that the mapping information is to be divided because the information amount of the extracted mapping information is 1000 bytes or more.

  When the dividing unit 142 divides the extracted mapping information (Yes in S133), the dividing unit 142 divides the mapping information (S134), and divides the divided data (hereinafter referred to as divided data) with a predetermined time interval. The data is sequentially transmitted to the controller 20 (S135).

  In this case, as illustrated in FIG. 14, the dividing unit 142 divides the extracted mapping information into divided data 1 and divided data 2 so that the information amount is 1000 bytes or less, and the divided data 1 and the divided data are divided. 2 are sequentially transmitted to the controller 20 with a predetermined time interval.

  On the other hand, when the predetermined information amount is 4000 bytes, the dividing unit 142 determines that the mapping information is not divided because the information amount of the extracted mapping information is less than the predetermined information amount.

  When not dividing the extracted mapping information (No in S133), the dividing unit 142 transmits the mapping information to the controller 20 without dividing (S136).

  If there is no corresponding mapping information as a result of searching the storage unit 12 (No in S132), the dividing unit 142 notifies the controller 20 that synchronization is unnecessary (S137).

Through the above series of processing, the mapping processing of the mapping information between the ARP response device 100 and the controller 20 is executed.

[effect]
In the communication system according to the second embodiment of the present invention, the ARP responding device sequentially separates the divided data obtained by dividing the extracted mapping information so that the information amount is equal to or less than the predetermined information amount with a predetermined time interval. Send to controller. Thereby, even when the amount of information of the extracted mapping information is large, the mapping information can be transmitted to the controller without compressing the communication band.

Therefore, it is possible to reduce the communication load on the network when mapping information is synchronized.

10 ARP response device 11 communication unit 12 storage unit 13 response processing unit 14 synchronization processing unit 15 division unit 20 controller 21 communication unit 22 switch control unit 23 storage unit 24 storage unit 25 determination unit 26 synchronization request unit 30 switch 31 switch 40 terminal 41 Terminal 100 Response device 140 Synchronization processing unit 141 Extraction unit 142 Division unit

Claims (8)

A response device that holds a plurality of address resolution information and responds to an address resolution request using the plurality of address resolution information;
A controller capable of communicating with the response device and controlling a switch on the network;
When the responding device holds the new address resolution information, it sends the new address resolution information to the controller,
When the controller receives the new address resolution information, the controller generates a first time when the new address resolution information is generated, and a second time when the address resolution information received immediately before the reception is generated. And whether to synchronize the addressing information with the responding device based on the time of
When it is determined that the synchronization is to be performed, the address resolution information held by the responding device between the second time and the first time is synchronized with the controller.
2. The controller according to claim 1, wherein the controller determines that the synchronization is performed when a time interval between the first time and the second time is equal to or greater than a predetermined threshold value. Communications system.
The response device is:
Dividing address resolution information synchronized with the controller,
The communication system according to claim 1 or 2, wherein the divided address resolution information is transmitted to the controller.
The communication system according to claim 3, wherein the response device divides address resolution information synchronized with the controller into a predetermined amount of information.
The controller is an OpenFlow controller,
The communication system according to any one of claims 1 to 4, wherein the synchronization is performed via an OpenFlow channel.
A controller that controls a switch on the network,
A storage unit for holding address resolution information;
A storage unit for storing the received address resolution information in the storage unit;
When the storage unit receives the address resolution information, based on a first time when the address resolution information is generated and a second time when the address resolution information received immediately before the reception is generated A determination unit that determines whether or not to synchronize the address resolution information with a response device that performs a response to the address resolution request;
A synchronization request unit that requests synchronization of address resolution information generated between the second time and the first time when the determination unit determines to perform the synchronization;
A controller comprising:
A response device that holds a plurality of address resolution information and responds to an address resolution request using the plurality of address resolution information;
A controller capable of communicating with the response device and controlling a switch on the network;
A method for synchronizing address resolution information performed by a communication system including:
Sending the new address resolution information to the controller when the responding device holds the new address resolution information;
When the controller receives the new address resolution information, a first time when the new address resolution information is generated and a second time when the address resolution information received immediately before the reception is generated Determining whether or not to synchronize the response device and address resolution information based on the time of
Synchronizing the address resolution information held by the responding device between the second time and the first time with the controller when the controller determines to perform the synchronization;
A method of synchronizing address resolution information.
To the computer that controls the switch on the network and holds the address resolution information,
When the new address resolution information is received, based on the first time when the new address resolution information is generated and the second time when the address resolution information received immediately before the reception is generated, A process for determining whether or not to synchronize address resolution information with a response device that responds to an address resolution request;
A process for requesting synchronization of address resolution information generated between the second time and the first time when it is determined that the synchronization is performed;
A program characterized by having executed.

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