JP2023088763A - Control device, device - Google Patents

Abstract

To provide a technique capable of registering a device by a control device even when multicast communication has failed.SOLUTION: A communication unit 110 is capable of multicasting the first message to search for registering a candidate device 200 and receive a second message, which is a response to the first message, unicasted from the device 200, and after broadcasting a third message with the same content as the first message, receive a fourth message, which is a response to the third message, unicasted from the device 200. A control unit 140 is configured so as to, when the communication unit 110 receives at least one of the second message and the fourth message unicasted, control the communication unit 110 to acquire a piece of information for registering the device 200.SELECTED DRAWING: Figure 1

Description

TECHNICAL FIELD The present disclosure relates to control technology, and more particularly to control devices and devices that register devices.

ECHONET Lite (registered trademark) is one of the communication standards for a HEMS (Home Energy Management System) controller to control devices such as air conditioners and lighting in a home network. In this communication standard, it is necessary to register the device in the control device in order to allow the device to communicate with the HEMS controller (control device). In the procedure for registering devices in the control device, the control device searches for devices that are registration candidates using multicast communication (see, for example, Non-Patent Document 1).

Hamamoto, Sugimoto, Washizu, Ishikawa, Murakami, Sugimura, Mori, Isshiki, ``Survey of implementation status of home routers that hinder interoperability of ECHONET Lite-equipped devices, and proposal of method for improving interoperability'', Information Processing Society of Japan Transactions on Consumer Devices & Systems, Japan, January 2019, Vol. 9, No. 1, p. 11-31

For example, IGMP (Internet Group Management Protocol) is used as a protocol for performing multicast group management. However, if there is a difference in IGMP function implementation between devices and routers, multicast packets will not be transferred. As a result, the control device cannot find the device and cannot register the device with the control device.

The present disclosure has been made in view of such circumstances, and an object thereof is to provide a technology that enables device registration in a control device even if multicast communication fails.

In order to solve the above problems, a control device according to one aspect of the present disclosure multicasts a first message for searching for devices that are candidates for registration, and then sends a second message, which is a response to the first message, to the device. a communication unit capable of unicast reception from the device and capable of unicast receiving a fourth message, which is a response to the third message, from the device after broadcasting a third message having the same content as the first message; a control unit that causes the communication unit to acquire information for registering the device when the communication unit receives at least one of the second message and the fourth message by unicast.

Another aspect of the disclosure is an apparatus. This device is registered in the control device, and multicasts a first message for notifying the existence of information in the device, and also broadcasts a second message having the same content as the first message. and, when the control device receives at least one of the first message multicast-transmitted from the communication unit and the second message broadcast-transmitted from the communication unit, the control unit causes the communication unit to provide information in the device to the control device. And prepare.

It should be noted that any combination of the above-described components and expressions of the present disclosure converted between methods, devices, systems, computer programs, recording media recording computer programs, etc. are also effective as aspects of the present disclosure. be.

According to the present disclosure, it is possible to register a device in a control device even if multicast communication fails.

It is a figure which shows the structure of the control system which concerns on a present Example. 2 is a sequence diagram showing an IGMP processing procedure executed in the control system of FIG. 1; FIG. FIG. 5 is a sequence diagram showing a registration procedure between a control device and a device to be compared in this embodiment; FIG. 2 is a sequence diagram showing a registration procedure between the control device and equipment in FIG. 1; 2 is a sequence diagram showing a table update procedure between the control device and equipment in FIG. 1; FIG. 3 is a sequence diagram showing another table update procedure between the control device of FIG. 1 and the device; FIG.

Before specifically describing the embodiments of the present disclosure, an outline of the present embodiments will be described. The embodiment relates to a control system for controlling the operation of lighting devices and air conditioners in facilities such as detached houses, condominiums, and apartments. The control system can also manage the power consumed at the facility. In a control system, devices such as a lighting device and an air conditioner are connected to a control device via a network, and the control device controls the devices through communication between the control device and the devices. An example of a control system is HEMS, and ECHONET Lite (registered trademark) is used for communication in HEMS.

In the control system, when a device is registered with the control device, communication between the control device and the device becomes possible. Here, registration means (i) storing device information such as an IP (Internet Protocol) address inside the control device, or (ii) setting a name to be displayed on the control device in addition to (i). to indicate that the In order to register a device with the control device, the control device searches for the device through multicast communication. In multicast communication, signals are sent to specific devices instead of being sent to all devices. Destinations in multicast communication are managed by routers. However, a situation occurs in which multicast communication fails due to an implementation defect (malfunction) of IGMP in a router or device. In that case, the control device cannot find the device by searching, and cannot register the device. As a result, communication between the controller and the equipment becomes impossible. In order to enable device registration in the control device even if multicast communication fails, the control device according to the present embodiment searches for devices using multicast communication and also searches for devices using broadcast communication.

FIG. 1 shows the configuration of a control system 1000. As shown in FIG. A control system 1000 includes a control device 100 , equipment 200 , a router 300 and a network 400 . The number of devices 200 included in control system 1000 is not limited to "1". Control system 1000 is installed in a facility. A facility is a building to be controlled by the control system 1000, such as a detached house. The facility is not limited to a detached house, and may be a dwelling unit of an apartment complex, an office building, a commercial facility, or the like. Control device 100 , device 200 and router 300 are connected to network 400 , and control device 100 and device 200 can communicate via network 400 under the control of router 300 . The network 400 supports standard protocols such as ECHONET Lite (registered trademark), for example.

The control device 100 functions as, for example, a HEMS controller and controls the operation of the device 200 . The control device 100 may be a single device or a connection of multiple devices. Control device 100 includes communication unit 110 , reception unit 120 , display unit 130 , control unit 140 and storage unit 150 . The communication unit 110 has a communication function of ECHONET Lite (registered trademark) and can communicate with the device 200 . The control unit 140 is configured by, for example, a microcomputer having a processor and memory. Various functions of the control unit 140 are realized by the computer system when the processor executes the programs recorded in the storage unit 150 .

One of the various functions is a function of controlling the operation of the device 200 , and the control device 100 displays an operation screen for receiving an operation on the device 200 on the display section 130 . The accepting unit 120 is a user interface capable of accepting an operation from a user, and is, for example, a button. Further, reception unit 120 may be a touch panel integrated with display unit 130 . Accepting unit 120 accepts a user's instruction for the operation screen displayed on display unit 130 . Reception unit 120 outputs the received instruction to control unit 140 . Control unit 140 generates a control command for instructing the operation of device 200 based on the instruction received by reception unit 120 . The communication unit 110 transmits control commands to the device 200 .

The device 200 is, for example, a lighting device and an air conditioner. The device 200 includes a communication section 210 , a control section 240 and a storage section 250 . The communication unit 210 has an ECHONET Lite (registered trademark) communication function and performs communication with the communication unit 110 . Communication unit 210 receives the control command from communication unit 110 . The control unit 240 executes operations according to control commands. For example, the control unit 240 turns on or off the operation of the device 200 .

The communication unit 110 of the control device 100 may be connected to a smart meter (not shown) and receive power information indicating power consumed in the facility. Control unit 140 generates a control command based on the power information received by communication unit 110 . For example, when the electric power exceeds the threshold value, the control unit 140 generates a control command to raise the set temperature of the air conditioner during cooling. The communication unit 110 transmits control commands to the device 200 . When the device 200 receives the control command from the control device 100, the device 200 performs an operation according to the control command, for example, an operation of increasing the set temperature during cooling.

The subject of an apparatus, system, or method in this disclosure comprises a computer. The main functions of the device, system, or method of the present disclosure are realized by the computer executing the program. A computer has a processor that operates according to a program as its main hardware configuration. Any type of processor can be used as long as it can implement functions by executing a program. The processor is composed of one or more electronic circuits including a semiconductor integrated circuit (IC) or LSI (Large Scale Integration). A plurality of electronic circuits may be integrated on one chip or may be provided on a plurality of chips. A plurality of chips may be integrated into one device, or may be provided in a plurality of devices. The program is recorded in a non-temporary recording medium such as a computer-readable ROM, optical disk, hard disk drive, or the like. The program may be pre-stored in a recording medium, or may be supplied to the recording medium via a wide area network including the Internet.

In order to execute communication in the control system 1000 as shown in FIG. 1, the device 200 is registered in advance in the control device 100 as described above. Since multicast communication is used for registration processing, IGMP, which is a protocol for performing multicast group management, will be described first.

FIG. 2 is a sequence diagram showing the IGMP processing procedure executed in the control system 1000. As shown in FIG. When the device 200 desiring to join the multicast group is activated (S10), the communication unit 210 of the device 200 transmits a Membership Report (Join message) to the router 300 (S12). Upon receiving the Membership Report from the device 200, the router 300 updates the management table so that the device 200 is included in the multicast group. The management table includes multiple entries each pairing a multicast address and an interface. The interface includes control device 100 and device 200 .

In order to maintain the group, the router 300 periodically transmits Membership Query to the control device 100 and the device 200 (S14, S16). Upon receiving the Membership Query from the router 300, the communication unit 210 of the device 200 transmits a Membership Report to the router 300 (S18). Upon receiving the Membership Query from the router 300, the communication unit 110 of the control device 100 transmits a Membership Report to the router 300 (S20). The router 300 deletes from the management table an interface that does not return a Membership Report.

Multicast communication may not be possible due to a mounting defect (malfunction) of the device 200 or the router 300 . For example, if the device 200 does not have IGMP installed, the communication unit 210 of the device 200 does not transmit the Membership Report. Also, if the device 200 and the router 300 have different IGMP versions and there is a compatibility problem, the device 200 cannot respond to the Membership Query. In these situations, the management table will not be generated correctly.

In order to explain the influence of such a failure of multicast communication on device registration, device registration by the control device 500 and the device 600 to be compared will be described here using FIG. FIG. 3 is a sequence diagram showing a registration procedure between the control device 500 and the device 600 to be compared. Here, for clarity of explanation, the router 300 arranged between the control device 500 and the device 600 is omitted. The control device 500 and the device 600 correspond to the control device 100 and the device 200, for example. The control device 500 receives a registration start operation from the builder (S100). The control device 500 multicasts a search request (S102). A search request is a message for searching for devices that are candidates for registration. The search request corresponds to the "own node instance list S request" of ECHONET Lite (registered trademark). Upon receiving the search request, the device 600 unicasts a response to the search request to the control device 500 (S104). The response includes information about the device 600 that is the transmission source, such as the IP address and information indicating the type of the device 600 . The information indicating the type of the device 600 indicates, for example, the class in which the device 600 is included.

Controller 500 receives the response. The control device 500 recognizes the existence of the device 600 based on the IP address included in the response, and also recognizes the type (class) of the device 600 . Subsequently, the control device 500 unicasts a device information request for requesting information specific to the device 600 to the device 600 (S106). Information specific to the device 600 is, for example, a node profile class. When the device 600 receives the device information request, the device 600 unicasts the device information, which is information specific to the device 600, to the control device 500 (S108).

The control device 500 receives device information. Based on the type of the device 600, the control device 500 unicasts a type information request for requesting information specific to the type of the device 600 to the device 600 (S110). Information specific to the type of device 600 is, for example, information included in the class of device 600 . Upon receiving the type information request, the device 600 unicasts the type information, which is information specific to the type of the device 600, to the control device 500 (S112).

The control device 500 displays the information of registrable devices showing the device 600 corresponding to the contents of the device information and the type information (S114). When multiple devices 600 are connected to the control device 500, the multiple devices 600 are included in the information on the registrable devices. The builder selects the device 600 to be registered while looking at the information on the devices that can be registered, and the control device 500 receives the selection operation (S116). The control device 500 stores the registration information of the device 600 selected by the selection operation in the correspondence table. This corresponds to registering the device 600 . The control device 500 receives a registration end operation from the builder (S118).

If multicast communication is not possible, the device 600 does not receive the search request multicast from the control device 500 . As a result, the device 600 cannot be registered with the control device 500 . Further, after the controller 500 is restarted, the device 600 becomes offline, and the device 600 cannot be operated from the controller 500 .

FIG. 4 is a sequence diagram showing a registration procedure between the control device 100 and the device 200. As shown in FIG. Again, for clarity of explanation, the router 300 arranged between the control device 100 and the device 200 is omitted. The reception unit 120 of the control device 100 receives a registration start operation from the builder (S200). Control unit 140 outputs a search request to communication unit 110 . The communication unit 110 multicasts a search request (first message) (S202).

When the communication unit 210 of the device 200 receives the search request, the control unit 240 causes the communication unit 210 to unicast a response (second message) to the search request to the control device 100 (S204). The response includes information about the device 200 that is the transmission source, such as the IP address and information indicating the type of the device 200 . The information indicating the type of the device 200 indicates, for example, the class in which the device 200 is included.

The communication unit 110 broadcasts a search request (third message) after a predetermined period of time, for example, 2 to 3 seconds, has elapsed since the multicast transmission of the search request (first message) (S206). The search request (first message) and search request (third message) have the same content. When the communication unit 210 of the device 200 receives the search request, the control unit 240 causes the communication unit 210 to unicast a response (fourth message) to the search request to the control device 100 (S208). The response (second message) and response (fourth message) have the same content. When the device 200 responds to both the multicast-transmitted search request (first message) and the broadcast-transmitted search request (third message), the control device 100 responds (second message) and responds (fourth message). Receive two responses. By staggering multicast and broadcast transmissions by a predetermined amount of time, crowding of responses received is avoided.

Here, the timing of multicast transmission of the search request (first message) and the timing of broadcast transmission of the search request (third message) are shifted. However, the multicast transmission of the search request (first message) and the broadcast transmission of the search request (third message) may be performed in parallel. The search request (first message) and response (second message) contain a common transaction ID (hereinafter referred to as "first transaction ID"). The search request (third message) and response (fourth message) contain a common transaction ID (hereinafter referred to as "second transaction ID"). The first transaction ID and the second transaction ID are different.

The communication unit 110 of the control device 100 receives the response. When the communication unit 110 receives the response (second message) and the response (fourth message), the control unit 140 generates the response (second message) and the response (second message) based on the first transaction ID and the second transaction ID. It recognizes that the response (fourth message) is the same, that is, the response is for the same device 200 . The control unit 140 recognizes the existence of the device 200 based on the IP address included in the response, and also recognizes the type (class) of the device 200 .

Subsequently, the communication unit 110 unicast-transmits a device information request (fifth message) to the device 200 to request information specific to the device 200 (S210). The information unique to the device 200 is, for example, a node profile class. Upon receiving the device information request, the communication unit 210 of the device 200 unicast-transmits the device information (sixth message), which is information unique to the device 200, to the control device 100 (S212).

The communication unit 110 of the control device 100 receives the device information. Based on the type of the device 200, the communication unit 110 unicast-transmits a type information request (seventh message) for requesting information specific to the type of the device 200 to the device 200 (S214). The information specialized for the type of device 200 is, for example, information included in the class of the device 200 . Upon receiving the type information request, the communication unit 210 of the device 200 unicasts the type information (eighth message), which is information specific to the type of the device 200, to the control device 100 (S216).

The control unit 140 causes the display unit 130 to display information on registrable devices indicating the device 200 corresponding to the contents of the registration information (S218). When multiple devices 200 are connected to the control device 100, the multiple devices 200 are included in the information of the registrable devices. The builder selects the device 200 to be registered while looking at the information on the devices that can be registered, and the reception unit 120 receives the selection operation (S220). The control unit 140 causes the storage unit 150 to store the information of the device 200 selected by the selection operation as a correspondence table. The correspondence table stores combinations of device information of the device 200 , type information of the device 200 , and IP address of the device 200 . This corresponds to registering the device 200 . The reception unit 120 receives a registration end operation from the builder (S222).

Multicast communication is defined by the ECHONET Lite (registered trademark) specifications, so it must be performed. Even if multicast communication of the search request (first message) fails, broadcast communication of the search request (third message) is also performed in order for the control device 100 to obtain a response. Broadcast communications are not managed at router 300 and are carried out throughout network 400 .

Using both multicast and broadcast communications to send search requests doubles the subsequent responses, equipment information requests, etc., thus doubling the traffic. When receiving a response (second message) and a response (fourth message) by unicast, the control unit 140 of the present embodiment causes the subsequent device information request or the like to be transmitted only once.

So far, a case has been described in which processing is started with the transmission of a signal (search request) from the control device 100 as the starting point, but below, the processing is started with the transmission of the signal from the device 200 Explain the case. The device 200 is registered with the control device 100 but does not register with the control device 100 . In other words, the device 200 does not store the IP address of the control device 100 . Therefore, when a state change occurs in device 200, such as a change in IP address or a change in temperature settings, device 200 multicasts a signal to control device 100 to inform control device 100 of the change in state. When multicast communication fails, this signal is no longer received by control device 100 , and control device 100 becomes unable to recognize state changes in device 200 . In order to deal with this, the present embodiment performs the following processing.

FIG. 5 is a sequence diagram showing a table update procedure between the control device 100 and the device 200. As shown in FIG. The device 200 has already been registered with the control device 100 . The communication unit 210 and the control unit 240 of the device 200 detect the IP address change (S250). This change occurs after the IP address is obtained when the device 200 is activated, after the IP address is obtained when the device 200 is activated, or when the IP address is switched from link-down to link-up. The control unit 240 outputs to the communication unit 210 a state change notification (first message) for informing the existence of information in the device 200, for example, a state change. The communication unit 210 multicasts the state change notification (first message) (S252). Further, the communication unit 210 broadcasts a state change notification (second message) having the same content as the state change notification (first message) (S254). The state change notification (first message) includes a transaction ID (hereinafter referred to as "first transaction ID"), and the state change notification (second message) includes a transaction ID (hereinafter referred to as "second transaction ID"). is included. The first transaction ID and the second transaction ID are different. The multicast transmission of the state change notification (first message) and the broadcast transmission of the state change notification (second message) may be performed in parallel.

The communication unit 110 of the control device 100 receives at least one of the multicast-transmitted state change notification (first message) and the broadcast-transmitted state change notification (second message). When the communication unit 110 receives the state change notification (first message) and the state change notification (second message), the control unit 140 receives the state change notification based on the first transaction ID and the second transaction ID. It is determined that the (first message) and the state change notification (second message) have the same content.

Following this, the communication unit 110 unicast-transmits an identification number request (third message) for requesting the identification number of the device 200 to the device 200 (S256). Upon receiving the identification number request, the communication unit 210 of the device 200 unicasts the identification number (fourth message) of the device 200 to the control device 100 (S258). Communication unit 110 of control device 100 receives the identification number from device 200 . The control unit 140 updates the correspondence table with the combination of the identification number and IP address of the device 200 (S260). This correspondence table is stored in the storage unit 150 .

FIG. 6 is a sequence diagram showing another table update procedure between the control device 100 and the device 200. As shown in FIG. The control unit 240 of the device 200 detects a change in the operating state of the device 200 (S300). This is the case when the equipment 200 is an air conditioner and the operation changes from stop to heating operation. The control unit 240 outputs to the communication unit 210 a state change notification (first message) for informing the presence of information in the device 200, for example, a state change. The communication unit 210 multicasts a state change notification (first message) (S302). Further, the communication unit 210 broadcasts a state change notification (second message) having the same content as the state change notification (first message) (S304). The state change notification (first message) contains the first transaction ID, and the state change notification (second message) contains the second transaction ID.

The communication unit 110 of the control device 100 receives at least one of the multicast-transmitted state change notification (first message) and the broadcast-transmitted state change notification (second message). When the communication unit 110 receives the state change notification (first message) and the state change notification (second message), the control unit 140 receives the state change notification based on the first transaction ID and the second transaction ID. It is determined that the (first message) and the state change notification (second message) have the same content.

According to this embodiment, since the search request is transmitted by multicast transmission and broadcast transmission, it is possible to register the device in the control device 100 even if the multicast communication fails. Also, since the timing of multicast transmission of the search request and the timing of broadcast transmission of the search request are staggered, it is possible to suppress the concentration of traffic. Moreover, since the multicast transmission of the search request and the broadcast transmission of the search request are executed in parallel, the extension of the waiting time can be suppressed. Also, since different transaction IDs are included in the search request for multicast transmission and the search request for broadcast communication, both can be distinguished. In addition, since unicast transmission of the signal following the search request is not duplicated, an increase in traffic can be suppressed.

Since the state change notification from the device 200 is multicast and broadcast, even if the multicast communication fails, the state change can be notified to the control device 100 . Moreover, since different transaction IDs are included in the status change notification sent by multicast and the status change notification sent by broadcast communication, they can be distinguished from each other.

A summary of one aspect of the present disclosure is as follows. A control device (100) according to an aspect of the present disclosure multicasts a first message for searching for a device (200) that is a candidate for registration, and then sends a second message, which is a response to the first message, to a device (200 ), and after broadcasting a third message having the same content as the first message, a fourth message, which is a response to the third message, can be unicast received from the device (200). a communication unit (110), and when the communication unit (110) unicast-receives at least one of the second message and the fourth message, the communication unit (110) transmits information for registering the device (200). and a control unit (140) for obtaining the

A communication unit (110) shifts the timing of multicast transmission of the first message and the timing of broadcast transmission of the third message.

A communication unit (110) broadcasts a third message after a predetermined period of time has passed since multicast transmission of the first message.

The communication unit (110) may perform multicast transmission of the first message and broadcast transmission of the third message in parallel.

A first transaction ID is included in the first message and the second message, a second transaction ID is included in the third message and the second message, and the control unit (140) controls the first transaction ID and the second transaction ID , it may be determined that the second message and the fourth message have the same content.

The second and fourth messages that can be unicast-received by the communication unit (110) include information indicating the type of the device (200), and the control unit (140) causes the communication unit (110) to acquire the device ( The information for registering the device (200) includes information unique to the device (200) and information specific to the type of the device (200). After unicasting a fifth message for requesting information to the device (200), unicasting a sixth message including information unique to the device (200) from the device (200), the communication unit (110) unicasts to the device (200) a seventh message for requesting information specific to the type of the device (200), and then sends a message containing the information specific to the type of the device (200). An eighth message may be unicast received from the device (200).

Another aspect of the present disclosure is the device (200). This device (200) is a device (200) registered in the control device (100), multicasts a first message for notifying the existence of information in the device (200), and and at least one of the first message multicast-transmitted from the communication unit (210) and the second message broadcast-transmitted from the communication unit (210) a control unit (240) that, when received by the control device (100), causes information in the device (200) to be provided from the communication unit (210) to the control device (100).

The first message contains the first transaction ID, the second message contains the second transaction ID, and the control device (100) calculates the first transaction ID based on the first transaction ID and the second transaction ID. It may be determined that the message and the second message have the same content.

The present disclosure has been described above based on the embodiments. It should be understood by those skilled in the art that this embodiment is an example, and that various modifications are possible in the combination of each component or each treatment process, and such modifications are within the scope of the present disclosure. .

In this embodiment, the control device 100 or the device 200 executes broadcast transmission after executing multicast transmission. However, not limited to this, for example, the control device 100 or the device 200 may execute multicast transmission after executing broadcast transmission. According to this modified example, the degree of freedom in configuration can be improved.

Reference Signs List 100 control device 110 communication unit 120 reception unit 130 display unit 140 control unit 150 storage unit 200 device 210 communication unit 240 control unit 250 storage unit 300 router 400 network 500 control device 600 Instrument, 1000 Control System.

Claims (8)

After multicasting a first message for searching for a device that is a registration candidate, a second message that is a response to the first message can be unicast received from the device, and the same as the first message. a communication unit capable of unicast-receiving a fourth message, which is a response to the third message, from the device after broadcasting a third message of content;
a control unit that causes the communication unit to acquire information for registering the device when the communication unit receives at least one of the second message and the fourth message by unicast;
A control device comprising: The control device according to claim 1, wherein the communication unit shifts the timing of multicast transmission of the first message and the timing of broadcast transmission of the third message. 3. The control device according to claim 2, wherein the communication unit broadcasts the third message after a predetermined period of time has passed since multicasting the first message. The control device according to claim 1, wherein the communication unit performs multicast transmission of the first message and broadcast transmission of the third message in parallel. the first message and the second message include a first transaction ID, the third message and the second message include a second transaction ID;
5. The method according to any one of claims 1 to 4, wherein the control unit determines that the second message and the fourth message have the same content based on the first transaction ID and the second transaction ID. Control device as described. The second message and the fourth message that can be unicast received by the communication unit include information indicating the type of the device,
The information for registering the device that the control unit causes the communication unit to acquire includes information specific to the device and information specific to the type of the device,
The communication unit unicast-transmits a fifth message for requesting information unique to the device to the device, and then unicast-receives a sixth message including information unique to the device from the device. death,
The communication unit unicast-transmits to the device a seventh message for requesting information specific to the type of the device, and then transmits an eighth message including information specific to the type of the device. 6. The control device according to any one of claims 1 to 5, wherein unicast reception is performed from the device. A device registered in a control device,
a communication unit that multicast-transmits a first message for notifying the presence of information in the device and broadcast-transmits a second message having the same content as the first message;
when the control device receives at least one of the first message multicast-transmitted from the communication unit and the second message broadcast-transmitted from the communication unit, information in the device is transmitted from the communication unit to the control unit; a control unit provided by the device;
equipment with the first message includes a first transaction ID and the second message includes a second transaction ID;
8. The device according to claim 7, wherein the control device determines that the first message and the second message have the same content based on the first transaction ID and the second transaction ID.

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