JP7121821B1 - Communication system, communication device, program, and processing method - Google Patents

Abstract

Kind Code: A1 In a communication system including a controller and a plurality of communication devices, the topology of the network is specified based on notifications from the plurality of communication devices to the controller without the controller transmitting control packets for collecting topology information. provide a way to Kind Code: A1 When each of a plurality of communication devices 200 receives a control packet in ad-hoc routing from an adjacent node which is another communication device with which a link is established, each of the plurality of communication devices 200 executes management processing of adjacent node information of the own device. and transmits notification information including information about the neighboring node to the controller 100 . A controller identifies the topology of the network based on the notification information received from the plurality of communication devices. [Selection drawing] Fig. 1

Description

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

Patent Document 1 describes an SDN (Software Defined Networking) controller using OpenFlow as a protocol used for communication between the controller and the switch.
[Prior art documents]
[Patent Literature]
[Patent Document 1] JP 2017-163383 A

According to one embodiment of the invention, a communication system is provided. A communication system may comprise a controller and a plurality of communication devices. When each of the plurality of communication devices receives a control packet in ad-hoc routing from an adjacent node that is another communication device that has established a link, each of the plurality of communication devices executes processing for managing adjacent node information of the own device, and A processing function may be provided for sending notification information containing information to the controller.

The control packet may be a Hello packet. The ad-hoc routing may be reactive ad-hoc routing. The processing function unit may determine whether or not to transmit the notification information to the controller based on the control packet received from the adjacent node and containing adjacent node information of the adjacent node. The processing function unit transmits the notification information to the controller when the own device is not included in the adjacent node information of the adjacent node included in the control packet received from the adjacent node; Notification information need not be sent to the controller. Each of the plurality of communication devices may have a transmitter that transmits the control packet to an adjacent node. The transmission unit may transmit the control packet including the adjacent node information of the own device to the adjacent node. The controller may conform to a communication protocol for centralized routing. The controller conforms to OpenFlow and does not need to transmit control packets for topology information collection to the plurality of communication devices. The controller may have a topology identification unit that identifies a topology of a network formed by the plurality of communication devices based on the notification information received from each of the plurality of communication devices.

According to one embodiment of the present invention, a communication device is provided. When a communication device receives a control packet in ad-hoc routing from an adjacent node that is another communication device with which a link has been established, the communication device executes processing for managing adjacent node information of the own device and sends a notification including information about the adjacent node. A processing function may be provided to send information to the controller.

According to one embodiment of the present invention, there is provided a program for causing a computer to function as the communication device.

According to one embodiment of the present invention, there is provided a processing method performed by a communication device. According to the processing method, when a communication device receives a control packet in ad-hoc routing from an adjacent node that is another communication device with which a link is established, management processing of adjacent node information of the communication device is performed, and information about the adjacent node is a transmitting step of transmitting to the controller notification information including:

It should be noted that the above summary of the invention does not list all the necessary features of the invention. Subcombinations of these feature groups can also be inventions.

An example of a communication system 10 is shown schematically. It is a conceptual diagram for explaining the processing in the communication system 10 according to the present embodiment. It is a conceptual diagram for explaining the processing in the communication system 10 according to the present embodiment. An example of the configuration of the SDN controller 100 is shown schematically. An example of the configuration of the SDN switch 200 is shown schematically. An example of the flow of processing by the SDN switch 200 is shown schematically. An example of the functional configuration of the SDN controller 100 is shown schematically. An example of the functional configuration of the SDN switch 200 is shown schematically. 1 schematically shows an example of a hardware configuration of a computer 1200 that functions as an SDN controller 100 or SDN switch 200. FIG.

A wireless mesh SDN is known in which a wireless mesh network with a plurality of SDN switches is centrally controlled (route control, etc.) by an SDN controller. OpenFlow is known as a protocol that implements SDN. In OpenFlow, each SDN switch sends node link information to the SDN controller. The SDN controller uses information received from a plurality of SDN switches to understand the network topology and uses it for route control (distributes routes from the SDN controller to the SDN switches). The SDN switch must always know the connection path to the SDN controller (even when starting up or changing topology). It is necessary to achieve communication between SDN switches even when the SDN controller fails. Concurrent use of ad-hoc routing (for example, AODV (Ad hoc On-Demand Distance Vector), etc.) is conceivable for such a problem. Ad-hoc routing allows backup paths to be maintained at each SDN switch through autonomous distributed processing. As a problem at the time of such combined use, an increase in overhead due to control packets is assumed. The communication system 10 according to this embodiment provides technology that can contribute to solving such problems. The communication system 10 includes a controller and a plurality of communication devices controlled by the controller. The controller may conform to a communication protocol for centralized routing.

Hereinafter, the present invention will be described through embodiments of the invention, but the following embodiments do not limit the invention according to the claims. Also, not all combinations of features described in the embodiments are essential for the solution of the invention.

FIG. 1 schematically illustrates an example communication system 10 . In the example shown in FIG. 1, the communication system 10 comprises an SDN controller 100 and multiple SDN switches 200 . The SDN controller 100 is an example of a controller, and the SDN switch 200 is an example of a communication device.

The SDN switch 200 may be any device as long as it can establish a wireless link with another SDN switch 200 . The SDN switch 200 may be, for example, a communication device installed in HAPS (High Altitude Platform Station), and may be, for example, a hardware type switch or a software type switch. The SDN switch 200 may be, for example, a communication device mounted on an unmanned aerial vehicle such as a drone, and may be, for example, a hardware type switch or a software type switch. The SDN switch 200 may be a mobile phone such as a smart phone, a tablet terminal, a PC (Personal Computer), or the like. SDN switch 200 may be an example of a communication device.

Here, a case where the communication system 10 conforms to OpenFlow and uses ad-hoc routing together will be described. The ad-hoc routing used by communication system 10 may be reactive ad-hoc routing. Here, a case where the communication system 10 uses AODV will be mainly described as an example, but the communication system 10 may use other reactive ad-hoc routing such as DSR (Dynamic Source Routing).

Normally, by such combination, the SDN switch 200 uses a routing table calculated by the SDN controller 100 according to a route search algorithm (ex. Dijkstra's method) and distributed according to OpenFlow, and a routing table defined by ad-hoc routing. can be done. The routing table calculated by the SDN controller 100 according to the route search algorithm (ex. Dijkstra's method) and distributed according to OpenFlow may become invalid in the event of a topology change or controller failure, but the routing table defined by ad-hoc routing is backed up. Can be used as a route. However, if OpenFlow and ad-hoc routing are used together without any devising, an increase in overhead due to control packets may become a problem.

FIG. 2 is a conceptual diagram for explaining processing in the communication system 10 according to this embodiment. In the known OpenFlow, for example, each of a plurality of SDN switches 200 sends an LLDP (Link Layer Discovery Protocol) packet transmission command from the SDN controller 100 to a neighboring node, which is another SDN switch 200 with which a link has been established. The SDN switch 200 that periodically transmits LLDP packets and receives the LLDP packets reports the information to the SDN controller 100 . Also, in known AODV, each of the plurality of SDN switches 200 periodically transmits a hello packet to an adjacent node, and each of the plurality of SDN switches 200 recognizes its own adjacent node from the received hello packet. If OpenFlow and AODV are simply used together, both the transfer of LLDP packets and the transmission of Hello packets will be performed, and overhead will increase due to the use of two types of control packets.

The communication system 10 according to the present embodiment does not use a control packet for collecting topology information in OpenFlow, such as an LLDP packet, and sends notification information to the SDN controller 100 when the SDN switch 200 receives a Hello packet. By configuring to transmit, the SDN controller 100 is made aware of the topology. This can reduce overhead.

FIG. 3 is a conceptual diagram for explaining processing in the communication system 10 according to this embodiment. Here, a case will be described where the communication system 10 has a configuration that achieves further overhead reduction with respect to the configuration described with reference to FIG.

By adopting the configuration shown in FIG. 2, for example, a Hello packet from SDN switch 200 b (may be referred to as switch b) to SDN switch 200 a (may be referred to as switch a) By (sending notification information about to the SDN controller 100), the SDN controller 100 recognizes the link between switch a and switch b. If nothing is done here, the hello packet will be sent from the switch a to the switch b as well. (Processing of transmitting notification information about to the SDN controller 100) may be wasted. That is, in this case, there is no need to transmit notification information from the switch b to the SDN controller 100 .

In the communication system 10 according to this embodiment, the hello packet is extended so that the SDN switch 200 transmits a hello packet including information about its own adjacent node to the adjacent node. Then, the SDN switch 200 that has received the Hello packet does not transmit the notification information to the SDN controller 100 when the adjacent node information included in the Hello packet includes its own device. Thereby, further overhead reduction can be realized.

FIG. 4 schematically shows an example of the configuration of the SDN controller 100. As shown in FIG. The SDN controller 100 includes a communication unit 102 , an OpenFlow processing unit 104 , a topology identification unit 106 , a topology storage unit 108 and a transfer rule storage unit 110 .

The communication unit 102 communicates with each of the multiple SDN switches 200 . The communication unit 102 may communicate with each of the multiple SDN switches 200 via a mesh network configured by the multiple SDN switches 200 .

The OpenFlow processing unit 104 executes processing related to OpenFlow. The OpenFlow processing unit 104 transmits the notification information to the topology identification unit 106 when the communication unit 102 receives the notification information transmitted by the SDN switch 200 .

The topology identification unit 106 identifies the topology of the network configured by the multiple SDN switches 200 using the notification information transmitted by the multiple SDN switches 200 . The topology storage unit 108 stores the topology identified by the topology identification unit 106. FIG. The OpenFlow processing unit 104 may perform route control based on the topology identified by the topology identification unit 106. FIG. The OpenFlow processing unit 104 may generate forwarding rules based on the topology identified by the topology identification unit 106 . The transfer rule storage unit 110 stores transfer rules generated by the OpenFlow processing unit 104 . The OpenFlow processing unit 104 may transmit the transfer rule to each of the multiple SDN switches 200 .

FIG. 5 schematically shows an example of the configuration of the SDN switch 200. As shown in FIG. The SDN switch 200 includes a communication unit 202 , an ad-hoc routing processing unit 206 , an adjacent node information storage unit 208 , an OpenFlow processing unit 210 and a transfer rule storage unit 212 .

A communication unit 202 communicates with the SDN controller 100 . The communication unit 202 communicates with other SDN switches 200 .

The ad-hoc routing processing unit 206 executes processing related to ad-hoc routing. The ad-hoc routing processing unit 206 may transmit control packets in ad-hoc routing to adjacent nodes. The ad-hoc routing processing unit 206, for example, transmits Hello packets to neighboring nodes according to predetermined conditions. The ad-hoc routing processing unit 206 periodically transmits Hello packets to adjacent nodes, for example, according to a predetermined cycle.

The ad-hoc routing processing unit 206 manages adjacent node information stored in the adjacent node information storage unit 208 . The adjacent node information includes identification information that can identify the SDN switch 200 registered as an adjacent node. The identification information may be any information that can identify the SDN switch 200 . For example, the identification information is a MAC address, a switch ID generated based on the MAC address, or the like.

For example, when a Hello packet is received from another SDN switch 200, the ad-hoc routing processing unit 206 determines that the SDN switch 200 as the transmission source is registered in the adjacent node information stored in the adjacent node information storage unit 208. If not, the SDN switch 200 is registered in the adjacent node information. Also, the ad-hoc routing processing unit 206, for example, confirms whether or not the hello packet is received periodically for each of the SDN switches 200 registered in the adjacent node information. For example, when the ad-hoc routing processing unit 206 does not receive a Hello packet from the SDN switch 200 registered in the adjacent node information for a predetermined period, the registration of the SDN switch 200 is canceled.

The OpenFlow processing unit 210 executes processing related to OpenFlow. When the OpenFlow processing unit 210 receives a transfer rule from the SDN controller 100, it stores it in the transfer rule storage unit 212. If the transfer rule is already stored in the transfer rule storage unit 212, the OpenFlow processing unit 210 updates the transfer rule. or The OpenFlow processing unit 210 determines the data transmission destination and the data relay destination according to the transfer rules stored in the transfer rule storage unit 212, and transfers the data.

FIG. 6 schematically shows an example of the flow of processing by the SDN switch 200. As shown in FIG. The SDN switch 200 may perform this process when it has established a link with at least one other SDN switch 200 .

In step (the step may be abbreviated as S) 102 , the SDN switch 200 transmits a Hello packet including its own adjacent node information to the other SDN switches 200 . In S<b>104 , the SDN switch 200 receives a Hello packet containing adjacent node information of the other SDN switch 200 from the other SDN switch 200 .

In S106, the SDN switch 200 registers the sender of the Hello packet received in S104 as an adjacent node. In S108, the SDN switch 200 determines whether or not the sender of the Hello packet received in S104 has already registered itself as an adjacent node. The SDN switch 200 determines that the SDN switch 200 is registered when the adjacent node information included in the Hello packet includes itself, and determines that the SDN switch 200 is not registered when it is not included. If it is determined to be registered, the process returns to S102, and if it is determined not to be registered, the process proceeds to S110.

At S<b>110 , the SDN switch 200 transfers the Hello packet received at S<b>104 to the SDN controller 100 . The SDN controller 100 calculates topology information from received Hello packets.

FIG. 7 schematically shows an example of the functional configuration of the SDN controller 100. As shown in FIG. The SDN controller 100 includes a communication unit 112 , a notification information acquisition unit 114 , a topology identification unit 116 , a topology storage unit 118 , a transfer rule generation unit 120 and a transfer rule storage unit 122 .

The communication unit 112 communicates with each of the multiple SDN switches 200 . The communication unit 112 may communicate with each of the multiple SDN switches 200 via a mesh network configured by the multiple SDN switches 200 . The communication unit 112 may be implemented by the communication unit 102 .

The notification information acquisition unit 114 acquires notification information received by the communication unit 112 from the SDN switch 200 . The notification information acquisition unit 114 transmits the acquired notification information to the topology identification unit 106 . The notification information acquisition unit 114 may be implemented by the OpenFlow processing unit 104 .

The topology identifying unit 116 identifies the topology of the network configured by the multiple SDN switches 200 based on the notification information received from each of the multiple SDN switches 200 . The topology identification unit 116 may be realized by the topology identification unit 106. FIG.

The topology storage unit 118 stores the topology identified by the topology identification unit 116. FIG. Topology storage unit 118 may be implemented by topology storage unit 108 .

Transfer rule generation unit 120 generates transfer rules based on the topology stored in topology storage unit 118 . The transfer rule generator 120 may be implemented by the OpenFlow processor 104 . The transfer rule storage unit 122 stores transfer rules generated by the transfer rule generation unit 120 . The communication unit 112 may transmit the transfer rule generated by the transfer rule generation unit 120 to each of the multiple SDN switches 200 .

FIG. 8 schematically shows an example of the functional configuration of the SDN switch 200. As shown in FIG. The SDN switch 200 comprises a storage unit 220 , a communication unit 230 and a processing function unit 240 .

The storage unit 220 stores various information. The storage unit 220 stores adjacent node information, for example. The storage unit 220 stores transfer rules, for example.

The communication unit 230 has a link establishment unit 232 , a Hello packet transmission unit 234 and a transfer rule reception unit 236 . A link establishment unit 232 establishes a link with another SDN switch 200 .

The Hello packet transmitting unit 234 transmits Hello packets according to predetermined conditions to other SDN switches 200 with which the link establishing unit 232 has established a wireless link. The Hello packet transmission unit 234 periodically transmits Hello packets to other SDN switches 200 at predetermined intervals, for example. The hello packet transmission unit 234 may transmit hello packets including the adjacent node information stored in the storage unit 220 to other SDN switches 200 . The Hello packet transmitter 234 may be implemented by the ad-hoc routing processor 206 .

The transfer rule receiver 236 receives transfer rules from the SDN controller 100 . Transfer rule receiver 236 stores the received transfer rule in storage 220 . The transfer rule receiver 236 may be implemented by the OpenFlow processor 210 . The communication unit 230 determines the data transmission destination and the data relay destination according to the transfer rule stored in the storage unit 220, and transfers the data.

The processing function unit 240 has a management processing execution unit 242 and a notification information transmission unit 244 . When receiving a control packet in ad-hoc routing from an adjacent node that is another SDN switch 200 with which a link has been established, the management processing execution unit 242 executes management processing of adjacent node information of the device itself. The control packet may be of any type as long as it is for confirming the adjacency relationship. The control packet is, for example, a Hello packet.

For example, if the SDN switch 200 that is the transmission source of the control packet is not registered in the adjacent node information, the management processing execution unit 242 registers the SDN switch 200 in the adjacent node information. Also, the management processing execution unit 242 checks whether or not the SDN switch 200 registered in the adjacent node information periodically receives control packets, for example. For example, when no control packet is received from the SDN switch 200 registered in the adjacent node information for a predetermined period, the management processing execution unit 242 cancels the registration of the SDN switch 200. The management processing execution unit 242 may be implemented by the ad-hoc routing processing unit 206 .

The notification information transmission unit 244 transmits notification information to the SDN controller 100 . For example, when the management processing execution unit 242 registers the SDN switch 200 in the adjacent node information, the notification information transmission unit 244 transmits notification information to the SDN controller 100 to notify that the SDN switch 200 has become an adjacent node. Send to Further, for example, when the registration of the SDN switch 200 is canceled by the management processing execution unit 242, the notification information transmitting unit 244 transmits notification information notifying that the SDN switch 200 is no longer an adjacent node to the SDN controller 100. Send to The notification information transmission unit 244 may be realized by the ad-hoc routing processing unit 206 or the OpenFlow processing unit 210.

The notification information transmission unit 244 may determine whether or not to transmit notification information to the SDN controller 100 based on a control packet including adjacent node information of the adjacent node received from the adjacent node. For example, the notification information transmitting unit 244 transmits the notification information to the SDN controller 100 when the own device is not included in the adjacent node information of the adjacent node included in the control packet received from the adjacent node, and when it is included, the notification information No information is sent to the SDN controller 100 . This prevents the adjacent node that transmitted the control packet from transmitting notification information to the SDN controller 100 even though the adjacent node has already notified the SDN controller 100 of the adjacent relationship with its own device.

FIG. 9 schematically shows an example hardware configuration of a computer 1200 that functions as the SDN controller 100 or SDN switch 200. As shown in FIG. Programs installed on the computer 1200 cause the computer 1200 to function as one or more "parts" of the apparatus of the present embodiments, or cause the computer 1200 to operate or perform operations associated with the apparatus of the present invention. Multiple "units" can be executed and/or the computer 1200 can be caused to execute the process or steps of the process according to the present invention. Such programs may be executed by CPU 1212 to cause computer 1200 to perform certain operations associated with some or all of the blocks in the flowcharts and block diagrams described herein.

Computer 1200 according to this embodiment includes CPU 1212 , RAM 1214 , and graphics controller 1216 , which are interconnected by host controller 1210 . Computer 1200 also includes input/output units such as communication interface 1222 , storage device 1224 , DVD drive, and IC card drive, which are connected to host controller 1210 via input/output controller 1220 . The DVD drive may be a DVD-ROM drive, a DVD-RAM drive, and the like. Storage devices 1224 may be hard disk drives, solid state drives, and the like. Computer 1200 also includes legacy input/output units, such as ROM 1230 and keyboard, which are connected to input/output controller 1220 via input/output chip 1240 .

The CPU 1212 operates according to programs stored in the ROM 1230 and RAM 1214, thereby controlling each unit. Graphics controller 1216 retrieves image data generated by CPU 1212 into a frame buffer or the like provided in RAM 1214 or itself, and causes the image data to be displayed on display device 1218 .

Communication interface 1222 communicates with other electronic devices over a network. Storage device 1224 stores programs and data used by CPU 1212 within computer 1200 . The DVD drive reads programs or data from a DVD-ROM or the like and provides them to the storage device 1224 . The IC card drive reads programs and data from IC cards and/or writes programs and data to IC cards.

ROM 1230 stores therein programs that are dependent on the hardware of computer 1200, such as a boot program that is executed by computer 1200 upon activation. Input/output chip 1240 may also connect various input/output units to input/output controller 1220 via USB ports, parallel ports, serial ports, keyboard ports, mouse ports, and the like.

The program is provided by a computer-readable storage medium such as DVD-ROM or IC card. The program is read from a computer-readable storage medium, installed in storage device 1224 , RAM 1214 , or ROM 1230 , which are also examples of computer-readable storage media, and executed by CPU 1212 . The information processing described within these programs is read by computer 1200 to provide coordination between the programs and the various types of hardware resources described above. An apparatus or method may be configured by implementing information operations or processing according to the use of computer 1200 .

For example, when communication is performed between the computer 1200 and an external device, the CPU 1212 executes a communication program loaded into the RAM 1214 and sends communication processing to the communication interface 1222 based on the processing described in the communication program. you can command. The communication interface 1222 reads transmission data stored in a transmission buffer area provided in a recording medium such as a RAM 1214, a storage device 1224, a DVD-ROM, or an IC card under the control of the CPU 1212, and transmits the read transmission data. Data is transmitted to the network, or received data received from the network is written in a receive buffer area or the like provided on the recording medium.

In addition, the CPU 1212 causes the RAM 1214 to read all or necessary portions of files or databases stored in an external recording medium such as a storage device 1224, a DVD drive (DVD-ROM), an IC card, etc. Various types of processing may be performed on the data. CPU 1212 may then write back the processed data to an external recording medium.

Various types of information, such as various types of programs, data, tables, and databases, may be stored on recording media and subjected to information processing. CPU 1212 performs various types of operations on data read from RAM 1214, information processing, conditional decisions, conditional branching, unconditional branching, and information retrieval, which are described throughout this disclosure and are specified by instruction sequences of programs. Various types of processing may be performed, including /replace, etc., and the results written back to RAM 1214 . In addition, the CPU 1212 may search for information in a file in a recording medium, a database, or the like. For example, when a plurality of entries each having an attribute value of a first attribute associated with an attribute value of a second attribute are stored in the recording medium, the CPU 1212 selects the first attribute from among the plurality of entries. search for an entry that matches the specified condition of the attribute value of the attribute, read the attribute value of the second attribute stored in the entry, and thereby determine the first attribute that satisfies the predetermined condition An attribute value of the associated second attribute may be obtained.

The programs or software modules described above may be stored in a computer-readable storage medium on or near computer 1200 . Also, a recording medium such as a hard disk or RAM provided in a server system connected to a dedicated communication network or the Internet can be used as a computer-readable storage medium, whereby the program can be transferred to the computer 1200 via the network. offer.

The blocks in the flowcharts and block diagrams in this embodiment may represent steps in the process in which the operations are performed or "parts" of the apparatus responsible for performing the operations. Certain steps and "sections" may be provided with dedicated circuitry, programmable circuitry provided with computer readable instructions stored on a computer readable storage medium, and/or computer readable instructions provided with computer readable instructions stored on a computer readable storage medium. It may be implemented by a processor. Dedicated circuitry may include digital and/or analog hardware circuitry, and may include integrated circuits (ICs) and/or discrete circuitry. Programmable circuits, such as Field Programmable Gate Arrays (FPGAs), Programmable Logic Arrays (PLAs), etc., perform AND, OR, EXCLUSIVE OR, NOT AND, NOT OR, and other logical operations. , flip-flops, registers, and memory elements.

A computer-readable storage medium may comprise any tangible device capable of storing instructions to be executed by a suitable device, such that a computer-readable storage medium having instructions stored thereon may be illustrated in flowchart or block diagram form. It will comprise an article of manufacture containing instructions that can be executed to create means for performing specified operations. Examples of computer-readable storage media may include electronic storage media, magnetic storage media, optical storage media, electromagnetic storage media, semiconductor storage media, and the like. More specific examples of computer readable storage media include floppy disks, diskettes, hard disks, random access memory (RAM), read only memory (ROM), erasable programmable read only memory (EPROM or flash memory) , electrically erasable programmable read only memory (EEPROM), static random access memory (SRAM), compact disc read only memory (CD-ROM), digital versatile disc (DVD), Blu-ray disc, memory stick , integrated circuit cards, and the like.

The computer readable instructions may be assembler instructions, Instruction Set Architecture (ISA) instructions, machine instructions, machine dependent instructions, microcode, firmware instructions, state configuration data, or instructions such as Smalltalk, JAVA, C++, etc. any source or object code written in any combination of one or more programming languages, including object-oriented programming languages, and conventional procedural programming languages such as the "C" programming language or similar programming languages; may include

Computer readable instructions are used to produce means for a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus, or programmable circuits to perform the operations specified in the flowchart or block diagrams. A general purpose computer, special purpose computer, or other programmable data processor, locally or over a wide area network (WAN) such as the Internet, etc., to execute such computer readable instructions. It may be provided in the processor of the device or in a programmable circuit. Examples of processors include computer processors, processing units, microprocessors, digital signal processors, controllers, microcontrollers, and the like.

In the above embodiment, the case where the SDN switches 200 establish a wireless link and wirelessly communicate with each other has been described as an example, but the present invention is not limited to this. The communication system 10 may include multiple communication devices that construct a wired network, and a controller that controls the multiple communication devices.

Although the present invention has been described above using the embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments. It is obvious to those skilled in the art that various modifications or improvements can be made to the above embodiments. It is clear from the description of the scope of the claims that forms with such modifications or improvements can also be included in the technical scope of the present invention.

The execution order of each process such as actions, procedures, steps, and stages in the devices, systems, programs, and methods shown in the claims, the specification, and the drawings is etc., and it should be noted that they can be implemented in any order unless the output of the previous process is used in the subsequent process. Regarding the operation flow in the claims, the specification, and the drawings, even if the description is made using "first," "next," etc. for convenience, it means that it is essential to carry out in this order. not a thing

10 communication system, 100 SDN controller, 102 communication unit, 104 OpenFlow processing unit, 106 topology identification unit, 108 topology storage unit, 110 transfer rule storage unit, 112 communication unit, 114 notification information acquisition unit, 116 topology identification unit, 118 topology Storage unit 120 Transfer rule generation unit 122 Transfer rule storage unit 200 SDN switch 202 Communication unit 206 Ad-hoc routing processing unit 208 Adjacent node information storage unit 210 OpenFlow processing unit 212 Transfer rule storage unit 220 Storage unit , 230 communication unit, 232 link establishment unit, 234 hello packet transmission unit, 236 transfer rule reception unit, 240 processing function unit, 242 management processing execution unit, 244 notification information transmission unit, 1200 computer, 1210 host controller, 1212 CPU, 1214 RAM, 1216 graphic controller, 1218 display device, 1220 input/output controller, 1222 communication interface, 1224 storage device, 1230 ROM, 1240 input/output chip

Claims (8)

a controller;
comprising a plurality of communication devices and
each of the plurality of communication devices,
a transmission unit that transmits a Hello packet in ad-hoc routing including adjacent node information of the adjacent node of the own device to an adjacent node that is another communication device that has established a link;
A processing function unit that, when receiving the Hello packet from the adjacent node, executes management processing of the adjacent node information of the device itself and transmits notification information including information about the adjacent node to the controller, If the device itself is not included in the adjacent node information of the adjacent node included in the Hello packet containing the adjacent node information of the adjacent node received from the adjacent node, the notification information is transmitted to the controller and included case, a processing function unit that does not transmit the notification information to the controller
A communication system having The communication system according to claim 1, wherein said ad-hoc routing is reactive ad-hoc routing. 3. A communication system according to claim 1 or 2 , wherein said controller conforms to a communication protocol for centralized routing. The communication system according to any one of claims 1 to 3 , wherein said controller conforms to OpenFlow and does not transmit control packets for topology information collection to said plurality of communication devices. The controller is
5. The method according to any one of claims 1 to 4 , further comprising: a topology identification unit that identifies a topology of a network configured by the plurality of communication devices based on the notification information received from each of the plurality of communication devices. Communication system as described. A communication device,
a transmission unit that transmits a Hello packet in ad-hoc routing including adjacent node information of the adjacent node of the own device to an adjacent node that is another communication device that has established a link;
A processing function unit that , when receiving the Hello packet from the adjacent node, executes management processing of the adjacent node information of the device itself and transmits notification information including information about the adjacent node to a controller, If the device itself is not included in the adjacent node information of the adjacent node included in the Hello packet that is received from the node and includes the adjacent node information of the adjacent node, the notification information is transmitted to the controller; , a processing function unit that does not transmit the notification information to the controller;
A communication device comprising: A program for causing a computer to function as the communication device according to claim 6 . A processing method performed by a communication device, comprising:
a transmission step of transmitting a Hello packet in ad-hoc routing including adjacent node information of an adjacent node of the own device to an adjacent node that is another communication device with which the communication device has established a link;
A transmitting step of executing a management process of the adjacent node information of the communication device and transmitting notification information including information about the adjacent node to a controller when the Hello packet is received from the adjacent node, If the device itself is not included in the adjacent node information of the adjacent node included in the Hello packet that is received from the node and includes the adjacent node information of the adjacent node, the notification information is transmitted to the controller; , a sending step of not sending the notification information to the controller;
A processing method comprising:

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