JP5002643B2 - Network construction method - Google Patents

Description

  The present invention relates to a method for constructing a network of installations such as lighting, air conditioning, or windows.

  In recent years, in order to automate installations installed in factories and buildings, these are connected to form a network. In the future, it is predicted that these networks will be built not only in factories and buildings but also in houses, and will spread widely in people's daily lives. Conventionally, work for constructing a network is performed manually, and an installer performs setting of a logical address of each device, communication setting between devices, and the like.

  As a network, a LAN (Local Area Network) system using token packets is known (see Patent Document 1). This system circulates one token packet between devices existing on the network in the order determined by the installer in advance, and only the device that received the token packet can send data on the network. Is. In order to circulate the token packet, the device address of the next stage is stored in the storage unit of each device existing on the network, and after receiving the token packet, each device refers to the storage area and the next device. A token packet is being sent to

Japanese Patent Publication No. 3-24109

  However, there is a problem that the conventional network construction performed manually is difficult unless it is a person with specialized knowledge. In the future, in order to penetrate the network construction that automates multiple installations, it is desirable to make it easy for people without specialized knowledge to build a network.

  In addition, in the LAN system using the token packet as described above, when a new device is added after the network is constructed, the next-stage device address stored in the storage unit of the previous device of the added device is set. It is necessary to change to the address of the device to be added. Conventionally, in such cases, resetting the previous device of the device to be added is performed, or jamming (disturbance signal) is output from the added device to the network in operation to block the token packet. By doing so, the entire network is being rebuilt.

  However, in the former, since the timing of resetting is irrelevant to the timing of circulating the token packet, if resetting is performed during system operation, data may be destroyed. In the latter case, data may be destroyed by a jamming signal.

  In addition, when a device is removed after network construction, it is necessary to change the next-stage device address stored in the previous-stage device to the next-stage device address. Problem arises.

  The present invention pays attention to such a problem and automatically constructs a network between installations to be automated, and also reconstructs a network when installations are added or removed after the network construction. An object of the present invention is to provide a network construction method capable of automatically performing the above.

  According to the first aspect of the present invention, one token packet is circulated in a predetermined order between a plurality of devices existing on a cyclic network, and only the device that has received the token packet receives data on the network. Is a network construction method that allows a device connected to a line cable to detect the idle state of the network, and when there is a predetermined number of timeouts, a device other than its own device Transmitting a probe packet that inquires whether or not the probe packet is connected, and transmitting the probe packet every time-out that is less than the predetermined number of times until a probe response packet that responds to the probe packet can be received. A network construction method characterized by comprising:

  The invention according to claim 2 of the present invention has a step of broadcasting a self-introduction packet for self-introduction of its own device when the probe response packet is received in the network construction method according to claim 1. It is characterized by.

  In the invention according to claim 3 of the present invention, one token packet is circulated in a predetermined order between a plurality of devices existing on the cyclic network, and only the device that has received the token packet receives data on the network. A network construction method in the case of adding a new device to a network that can send a message, a step of broadcasting a solicitation packet for soliciting a device to which a network master cannot participate, and the reception of the solicitation packet A new device generates a solicitation response packet and sends it to the master of the network, and the master of the network that has received the solicitation response packet sends a next hop update instruction packet to the device in the previous stage of the master. The process of generating and sending and the device address of the next stage It is a network construction method characterized by a step of updating the new device.

  In the invention according to claim 4 of the present invention, one token packet is circulated in a predetermined order between a plurality of devices existing on the cyclic network, and only the device receiving the token packet receives data on the network. A method of constructing a network when a device is removed from a network that is capable of transmitting a message, the step of removing the device from the network, and the removed device or the device in the previous stage from the network Broadcasting a reduction notification packet for notifying that the reduction has been removed, and each device that has received the reduction notification packet deletes and updates the address of the reduced device held by each device A network construction method characterized by comprising a process.

  The present invention automatically installs a network between installations by attaching the equipment to a plurality of installations that automate the equipment, and also automatically when installations are added or removed after the network is built. Can be rebuilt

FIG. 1 is a block diagram showing an internal configuration of a device for network connection according to the present invention (Example 1). FIG. (Example 2) which shows the procedure of network construction FIG. (Example 2) which shows the procedure of network construction FIG. (Example 2) which shows the procedure of network construction FIG. (Example 2) which shows the procedure of network construction FIG. (Example 2) which shows the procedure of network construction FIG. (Example 2) which shows the procedure of network construction FIG. (Example 2) which shows the procedure of network construction FIG. (Example 2) which shows the procedure of network construction A figure showing a state where a new installation is added to a network in a stable state (Example 3) Sequence diagram showing the procedure for adding a new installation to a network in a stable state (Example 3) Sequence diagram showing a procedure for explicitly removing from a network in a stable state (Example 4) Sequence diagram showing the procedure for implicit removal from a network in a stable state (Example 4) The figure which shows the format of the packet used by this invention The figure which shows positioning of transmission destination ID by transmission destination field identifier (DFI) Diagram showing packet type Diagram showing token packet format The figure which shows the format of a probe packet and a probe response packet The figure which shows the format of an invitation packet and an invitation response packet Figure showing format of solicitation result notification packet The figure which shows the format of a next hop update instruction packet Figure showing self-introduction packet format The figure which shows the format of the reduction notification packet Diagram showing operation code (OPC)

  Hereinafter, the best mode for carrying out the present invention will be described. In addition, this invention is not limited to the range demonstrated by each following Example, If it is a range which does not deviate from the summary, it can change and implement suitably.

  The first embodiment of the present invention will be described below. In this embodiment, a device for building a network will be described. FIG. 1 shows a device 10 as an object of the present invention and an installation 109 controlled by the device 10, which are a basic structural unit, and a plurality of devices are connected by a line cable.

  In FIG. 1, a device 10 includes a transmission / reception unit 100, a reception control unit 101, a reception information holding unit 102, a packet transmission / reception control unit 103, a timer unit 104, a transmission control unit 105, a transmission information holding unit 106, an upper layer control. The unit 107 and the installed object control unit 108 are provided, and the device 10 including these is connected to the installed object 109.

  The transmission / reception unit 100 is connected to a line cable serving as a network, performs parallel / serial conversion at the time of packet transmission, serial / parallel conversion at the time of reception, and performs encoding / decoding on the transmission path. The reception control unit 101 sends a packet received by the transmission / reception unit 100 to the reception information holding unit 102, extracts a data link layer header from the packet received by the transmission / reception unit 100, and sends the packet to the packet transmission / reception control unit 103. The packet includes a token packet, a probe packet, an invitation packet, an invitation result notification packet, a self-introduction packet, a reduction notification packet, and the like. Details of the various packets will be described later. The reception information holding unit 102 holds packets received by the transmission / reception unit 100 and sent via the reception control unit 101. For example, it holds a self-introduction packet of a device connected to the network. The packet transmission / reception control unit 103 refers to the data link layer header of the packet and recognizes the packet type and request. Then, a packet is autonomously generated for a packet to be processed in the data link layer according to the recognized type or request. On the other hand, packets that are not processed in the data link layer are sent to the upper layer control unit 107. Further, a time signal is sent from the timer unit 104 to the packet transmission / reception control unit 103, and the packet transmission / reception timing is controlled according to this time signal. The packet transmission / reception control unit 103 includes a packet autonomous generation unit 131 that autonomously generates a packet according to the description of the data link layer header and the time signal.

  The various packets autonomously generated by the packet autonomous generation unit 131 include a token packet, a probe packet, a probe response packet, an invitation packet, an invitation response packet, an invitation result notification packet, and the like. Details of the various packets will be described later.

  In addition, the packet transmission / reception control unit 103 includes an address holding unit 132 that holds the addresses of the devices in the previous stage, the next stage, and the next stage based on the own device. The preceding device address is used when the preceding device is unexpectedly removed based on its own device. Specifically, if the network master (hereinafter referred to as the domain master) is the previous device, if the device is removed, the domain master will be removed from the network, and the device will take over the domain master function. Like that. Even if the preceding device is not the domain master, the device is managed, and when the preceding device is unexpectedly removed, the fact is notified to the domain master. As a result, the network can be automatically reconstructed even if the previous device is removed. The next-stage device address is used when a token packet is passed to the next-stage device. The next-stage device address is used when the next-stage device is removed based on its own device. Thus, even if the next-stage device is unexpectedly removed, the token packet can be sent to the next-stage device, so that the network can be continuously operated.

  The timer unit 104 includes various timers for monitoring the network status. The timer unit 104 includes five types of timers: a network response monitoring timer 141, an idle state detection timer 142, a network state monitoring timer 143, a next stage monitoring timer 144, and a backoff timer 145.

  Here, various timers will be described. The network response monitoring timer 141 is a timer used for monitoring whether or not there is a response when a packet that requires a response from the other party is transmitted to a certain device. The idle state detection timer 142 is a timer used for detecting an idle state in the network. The network connection monitoring timer 143 is a timer that monitors whether or not its own device is connected to the network. The next-stage monitoring timer 144 is a timer that monitors whether or not the next-stage device that has passed the token packet functions normally. The back-off timer 145 waits for transmission of a response packet for a certain period of time in order to prevent a collision with a response packet from another device when receiving a probe packet or an invitation packet and transmitting a response packet. It is a timer. When any one of the network response monitoring timer 141, the idle state detection timer 142, the network state monitoring timer 143, the next stage monitoring timer 144, and the backoff timer 145 times out, a time signal indicating that is sent to the packet transmission / reception control unit 103. Notify

  The transmission control unit 105 performs packet transmission control. Transmission control includes an autonomous mode and a higher mode. The autonomous mode is a mode for transmitting to the transmission / reception unit 100 based on the packet transmitted from the packet transmission / reception control unit 103. Further, the upper mode is a mode in which the packet transmission / reception control unit 103 and the upper layer control unit 107 transmit to the transmission / reception unit 100 based on the packet previously held in the transmission information holding unit 106. The transmission information holding unit 106 holds packets sent from the packet transmission / reception control unit 103 and the upper layer control unit 107. The upper layer control unit 107 controls packets that are not processed by the packet transmission / reception control unit 103, such as a self-introduction packet and a reduction notification packet. The installation control unit 108 controls the installation 109 based on the packet sent from the upper layer control unit 107 and performs control to notify the upper layer control unit 107 of a request from the installation 109. The installation object 109 includes, for example, lighting, air conditioning, windows, and the like, and is an installation object to be controlled by this network. The installation can be anything that you want to control. A network can be automatically constructed by installing the device 10 in the installation 109 and generating and controlling various packets.

  Although not particularly illustrated, the device 10 includes a storage medium that stores a network construction program. A computer (not shown) in the device 10 executes the network construction program stored in the storage medium, thereby causing each of the above components to function, and each component performs a process.

Next, the packet format handled in this embodiment will be described.
As shown in FIG. 14, the packet includes a transmission destination field identifier (DFI) 1401, a transmission destination domain ID or installation location code (DDID) 1402, a transmission destination device (node) ID or device code (DNID) 1403, a transmission source domain. A data link layer header including an ID (SDID) 1404, a transmission source device (node) ID (SNID) 1405, a packet type (PT) 1406, an operation code (OPC) 1407, and a length of a data part (LEN) 1408; A data part (DATA) 1409 and a CRC 1410 indicating the reliability of the packet are provided. Data link layer headers extracted by the reception control unit 101 are denoted by reference numerals 1401 to 1408.

  A transmission destination field identifier (DFI) 1401 identifies the location of the transmission destination, and includes a network management mode and a normal mode. As shown in FIG. 15, the network management mode is a mode for identifying a transmission destination by associating a transmission destination domain ID or installation location code (DDID) 1402 with a transmission destination node ID or device code (DNID) 1403. On the other hand, the normal mode is a mode for identifying a transmission destination by associating a location code with a device code. Naturally, it is natural for a user to request such as “I want to lower the temperature of the air conditioning in this room” or “I want to darken the lighting in this room” without worrying about the logical ID of the device. is there. Since the location code and the device code are already defined as specifications, these values are used in the header so that the transmission destination information can be specified in the form of “where + any device”. The network management mode is “0x01”, and the normal mode is “0x00”.

  The transmission destination and transmission source domain IDs and node IDs 1402 to 1405 are set to “0x00” when they are not defined. When the transmission destination domain ID is “0x00”, communication is possible only with a device in the domain. When broadcasting a packet, the domain ID and node ID of the transmission destination are set to “0xFF”.

  The packet type 1406 recognizes the packet type. As shown in FIG. 16, the packet types processed in the data link layer are “0x00” to “0x06”, and the packet type passes the packet to the upper layer. Are "0x10" to "0xA2". In addition, there are packet types processed in the data link layer according to the OPC value, and there are “0x20” to “0x22”. In the following, various packets essential for network construction will be described.

  A packet whose packet type is “0x00” is a token packet. The token packet is a packet that circulates between devices existing on the network, and only the device that has received the token packet can transmit data on the network. The format of the token packet is shown in FIG.

  A packet with a packet type of “0x01” is a probe packet. The probe packet is a packet used in the first stage of network construction, and a device that has received the probe packet generates a probe response packet that responds to the probe packet. The format of the probe packet and the probe response packet is shown in FIG.

  A packet whose packet type is “0x02” is an invitation packet. The solicitation packet is a packet that the network master (domain master) built in the domain checks whether there is a device that wants to join the network, and the device that receives the solicitation packet responds to the solicitation packet. Generate a response packet. The format of the solicitation packet and the solicitation response packet is shown in FIG.

  Packets with a packet type of “0x03” are solicitation result notification packets. The solicitation result notification packet is a packet for notifying the device that has sent the solicitation response packet, and the data unit 1409 is provided with a uID value, a node ID value, and a next device address (next hop). Has been. The format of the solicitation result notification packet is shown in FIG.

  A packet with the packet type “0x06” is a next hop update instruction packet. The next hop update instruction packet is a packet used when a device is added to the network. This is a packet for instructing a device that transmits a token packet to the added device to update the next device address (next hop). The device that has received the packet updates the next-stage device address to the added device address. The format of the next hop update instruction packet is shown in FIG.

  A packet with a packet type of “0x11” is a self-introduction packet. The self-introduction packet is a packet used when the device is normally connected to the network. The self-introduction packet is broadcast to all domains or all nodes. In addition, it may be broadcast at a fixed period. The format of the self-introduction packet is shown in FIG. The data portion of the packet includes a code indicating position information such as coordinates and installation location, user ID information (uID), a device code indicating device information, and the like. For example, the ID information is an ID whose uniqueness is guaranteed all over the world, such as an Ethernet MAC address or a ubiquitous ID center ucode. In addition, if the position information is coordinates, the three-dimensional coordinates in the space are expressed as x-axis, y-axis, and z-axis, respectively, with reference to the coordinate origin of the design drawing. A place is defined and described with human-friendly attributes. In addition, the device information describes functions of the device such as lighting and doors.

  A packet with a packet type of “0x12” is a reduction notification packet. The reduction notification packet is a packet used when a device is reduced in the network. By broadcasting the packet in the network, an explicit reduction can be performed for other devices. The format of the reduction notification packet is shown in FIG.

  An operation code (OPC) 1407 is a code for recognizing that the packet is one of notification, request, and response. By referring to the operation code, it can be recognized that the packet indicates one of notification, request, and response. The operation code is shown in FIG.

  The length (LEN) 1408 of the data part indicates the capacity stored in the data part (DATA) 1409, and is represented by the number of bytes.

  A data unit (DATA) 1409 is a storage unit that stores data to be processed in an upper layer.

  The CRC 1410 indicating the reliability of the packet stores the result of the CRC16 calculation performed on the transmission destination field identifier (DFI) to the data part (DATA) 1409. CRC16 is a kind of linear code, and is a coding system that is strong against multi-bit continuous (burst) error detection. The CRC 16 is widely used for communication and disk error detection.

  As described above, according to the present embodiment, a network can be automatically constructed between devices by generating and controlling the above-described various packets using the device configured as described above. The installation connected to the equipment can be automated.

  The second embodiment of the present invention will be described below. In the present embodiment, a procedure for automatically constructing a network between devices using the devices and various packets described in the first embodiment will be described with reference to FIGS. It is assumed that the device 10 is attached to the installation object.

  Alpha is the first installation to be connected to the line cable used for network construction. When Alpha is connected to the line cable, the idle state detection timer 142 of the timer unit 104 provided in Alpha repeats timeout (see FIG. 2). When the idle state detection timer 142 has timed out seven times, this is notified to the packet transmission / reception control unit 103, and the packet autonomous generation unit 131 of the packet transmission / reception control unit 103 inquires whether it is connected to the network. A probe packet is autonomously generated and transmitted from Alpha (see FIG. 3).

  However, in this case, an installation other than Alpha does not yet exist on the network, so that a probe response packet that responds to the probe packet cannot be received. Alpha continues to transmit the probe packet every time the idle state detection timer 142 in Alpha repeats the timeout three times until the probe response packet can be received (see FIG. 4). In this case, since the probe response packet could not be received, Alpha sets the node ID to 0x01. If there is a previously used node ID, the ID can be used with priority.

  When Bravo, which is an installation other than Alpha, is connected to the network (see FIG. 5), Bravo, like Alpha, idle time detection timer 142 of timer unit 104 in Bravo repeats timeout. Bravo also generates a probe packet inquiring whether it is connected to the network when the idle state detection timer 142 has timed out seven times, but since Alpha is already connected to the network, Bravo Receives the probe packet transmitted by Alpha (see FIG. 6).

  When Bravo receives the probe packet from Alpha, the fact is sent to the packet transmission / reception control unit 103, and the packet autonomous generation unit 131 of the packet transmission / reception control unit 103 generates a probe response packet in response to the probe packet and transmits it from Bravo. (See FIG. 7). In this case, Bravo transmits the probe response packet, and simultaneously sets the node ID to 0x02, and holds Alpha (0x01) at the next-stage address held by the address holding unit 32 of the packet transmission / reception control unit 03. . If the previously used node ID does not overlap with the Alpha node ID, the ID can be set with priority.

  On the other hand, when Alpha receives the probe response packet from Bravo, it recognizes that an installation other than itself is connected to the network, and at the same time, the next-stage address held by the address holding unit 132 of the packet transmission / reception control unit 103. Holds Bravo (0x02). After that, the packet autonomous generation unit 131 of the Alpha packet transmission / reception control unit 103 autonomously generates a token packet and a self-introduction packet and transmits them to Bravo (see FIG. 8). When Bravo receives the token packet and the self-introduction packet from Alpha, the self-introduction packet of the packet transmission / reception control unit 103 is autonomously received by the packet autonomous generation unit 131 of the packet transmission / reception control unit 103. It is generated and transmitted to Alpha together with the token packet (see FIG. 9). As described above, when a network is constructed between the two installations Alpha and Bravo, a stable state is obtained.

  As described above, according to the present embodiment, it is possible to automatically construct a network between devices simply by attaching a device to an installation and connecting it to a line cable.

  The third embodiment of the present invention will be described below. In the present embodiment, a procedure for automatically reconstructing a network between devices when a new installation is added to the network constructed in the second embodiment will be described with reference to FIGS. 10 and 11.

  It is assumed that Charlie is a new installation to be added to the network (see FIG. 10). When Charlie is connected to the line cable, the idle state detection timer 142 of Charlie's timer unit 104 repeats timeout. However, since the network has already been constructed by Alpha and Bravo and is in a stable state, the probe packet transmitted after Charlie times out seven times is not accepted, and Charlie cannot join the network as it is.

  On the other hand, either Alpha or Bravo on the network that is already in a stable state becomes a network master (hereinafter referred to as a domain master), and packet transmission / reception control is performed for soliciting an installation that has not yet joined the network. The packet autonomous generation unit 131 of the unit 103 generates autonomously and broadcasts it to the network. In the present embodiment, the first Alpha connected to the network becomes the domain master, and the Alpha broadcasts an invitation packet (STEP 1).

  When Charlie receives the broadcast solicitation packet, the solicitation response packet is autonomously generated by the packet autonomous generation unit 131 of the packet transmission / reception control unit 103, and the solicitation response packet is transmitted to Alpha that broadcasts the solicitation packet (STEP 2). . At this time, Charlie may transmit a node ID held by Charlie to Alpha. When Alpha receives an invitation response packet from Charlie, Alpha recognizes that Charlie wants to join the network.

  Alpha holds the token packet from the broadcast of the solicitation packet to the reception of the solicitation response packet. Alpha receiving the solicitation response packet autonomously generates a next hop update instruction packet, transmits it to Bravo together with the token packet, and instructs the next stage address to be Charlie (STEP 3). Upon receiving the instruction, the address holding unit 132 in the Bravo packet transmission / reception control unit 103 updates the next-stage address to the Charle address. Bravo notifies Alpha that the address of the next stage has been updated together with the token packet (STEP 4). Alpha determines the node ID so that the node ID of Charlie does not overlap on the network, and autonomously generates a solicitation result notification packet by the packet autonomous generation unit 131 of the packet transmission / reception control unit 103 and broadcasts it. When Charlie receives the solicitation result notification packet, Charlie holds the node ID notified from Alpha in the reception information holding unit 102, and Alpha (0x01) as the next-stage address held in the address holding unit 132 of the packet transmission / reception control unit 103. ). After this processing is completed, the acknowledgment code is notified to Alpha (STEP 5).

  Alpha holds the token packet from when the solicitation result notification packet is broadcast until the acknowledgment code is received. Alpha receiving the acknowledgment code transmits a token packet to Bravo, and Bravo transmits a token packet to Charlie (STEP 6). Charlie receives the token packet from Bravo, recognizes that the previous address is Bravo, and holds Bravo (0x02) in the previous address held by the address holding unit 132 in the packet transmission / reception control unit 103. To do. After Charlie receives the token packet from Bravo, Charlie autonomously generates a self-introduction packet by the packet autonomous generation unit 131 in the packet transmission / reception control unit 103 and broadcasts it. Alpha and Bravo hold Charlie's self-introduction packet in the received information holding unit 102. After broadcasting the self-introduction packet, Charlie sends a token packet to Alpha. Thereby, installations can be added to the network in a stable state, and the network can be automatically reconstructed between devices.

  As described above, according to this embodiment, the network is automatically reconstructed between devices without newly resetting the network in a stable state or outputting jamming (jamming signal), and a new installation is added. Can do.

  The fourth embodiment of the present invention will be described below. In the present embodiment, when an installation object is removed from the network constructed in the second embodiment or the third embodiment, the procedure for automatically reconstructing the network between other devices will be described with reference to FIGS. Will be described.

  The network is built with Alpha, Bravo, Charlie, and Delta and is in a stable state. A case where Charlie is removed in this state will be described. There are two types of reduction: explicit reduction and implicit reduction.

  First, an explicit reduction will be described. Explicit reduction means that the installation to be removed notifies the network of the reduction itself. In the stable state, token packets are transmitted in the order of the devices Alpha, Bravo, Charlie, Delta, Alpha,. In each device, the idle state detection timer 142 of the timer unit 104 monitors whether to time out. This is to monitor whether or not its own device is disconnected from the network. If the state is stable, the idle state detection timer 42 does not time out (step 1).

  Assume that a user using the installation object 109 gives a reduction instruction to the device 10 in order to replace the device 10 attached to Charlie (step 2). After receiving the token packet from Bravo, Charlie autonomously generates a reduction notification packet by the packet autonomous generation unit 131 and broadcasts it to the entire network (STEP 3). Bravo in the previous stage of Charlie recognizes that Charlie will be removed, and updates the address of the next stage held in the address holding unit 132 of the packet transmission / reception control unit 103 from Charlie to Delta. In addition, the address holding unit 132 in Alpha and Delta of other installed objects is also updated (step 3). Charlie broadcasts the deduction notification packet and then transmits the token packet to Delta. At this point, Charlie's explicit removal process is complete. The token packet is then transmitted from Delta to Alpha and from Alpha to Bravo, and Bravo transmits the token packet to the updated Delta (step 5). As described above, when the installation is explicitly removed from the network in the stable state by steps 1 to 5, the network can be automatically reconstructed between the remaining devices.

  Next, an implicit reduction will be described. Implicit reduction means that the installation to be reduced does not notify the network of the reduction itself, but performs the reduction unexpectedly. For example, when the power is suddenly turned off or the communication cable is disconnected, the installation items are unexpectedly reduced. Also, it is performed when the explicit deinstallation fails, that is, when the deferred notification packet is broadcast but the previous installation cannot recognize the notification. In the stable state, token packets are transmitted in the order of the installation objects Alpha, Bravo, Charlie, Delta, Alpha,. In each device, the idle state detection timer 142 of the timer unit 104 monitors whether to time out. If the state is stable, the idle state detection timer 142 will not time out (step 1).

  It is assumed that Charlie has been unexpectedly removed for some reason. At this time, Alpha, Bravo, and Delta connected to the network have not received the reduction notification, so that the token packet circulates through the network as usual (step 2). However, even if Bravo transmits a token packet to Charlie, which is disconnected from the network, Charlie does not exist, so Bravo's next-stage monitoring timer 144 times out after a certain time. (Step 3) At this point, Bravo determines that Charlie is no longer on the network and uses the Charlie ID as the sender ID to autonomously generate a deduction notification packet on behalf of Charlie. To broadcast. (Step 4) After that, Bravo transmits a token packet to the next-stage address Delta held in the address holding unit 132, and simultaneously updates the next-stage address held in the address holding unit 132 from Charlie to Delta. In addition, the address holding unit 132 in Alpha and Delta of other installed objects is also updated. Bravo broadcasts a deduction notification packet and then transmits a token packet to Delta. At this point, Charlie's implicit removal process is complete. The token packet is then transmitted from Delta to Alpha and from Alpha to Bravo, and Bravo transmits the token packet to the updated Delta (step 5). As described above, when the installation object is implicitly removed from the network in the stable state by steps 1 to 5, the network can be automatically reconstructed between the remaining devices.

  As described above, according to the present embodiment, even when a device is removed for any reason after the network is constructed, the network can be automatically reconstructed between the remaining devices.

  The present invention can be automated by constructing a network between installations installed in a house as well as in a factory or a building, and is expected to penetrate widely into daily life of people.

DESCRIPTION OF SYMBOLS 10 Apparatus 100 Transmission / reception part 101 Reception control part 102 Reception information holding part 103 Packet transmission / reception control part 131 Packet autonomous generation part 132 Address holding part 104 Timer part 141 Network response monitoring timer 142 Idle state detection timer 143 Network state monitoring timer 144 Next stage monitoring Timer 145 Back-off timer 105 Transmission control unit 106 Transmission information holding unit 107 Upper layer control unit 108 Installation object control unit 109 Installation object

Claims (3)

A network construction method in which one token packet is circulated between a plurality of devices existing on a cyclic network in a predetermined order so that only the device that has received the token packet can transmit data on the network. And
A step of measuring the time for the device connected to the network cable to detect the idle state of the network;
When there is a predetermined number of timeouts, a step of transmitting a probe packet inquiring whether or not a device other than its own device is connected to the network;
Sending the probe packet every time-out less than the predetermined number of times until a probe response packet in response to the probe packet can be received;
A network construction method characterized by comprising:   The network construction method according to claim 1, further comprising a step of broadcasting a self-introduction packet for self-introduction of its own device when the probe response packet is received. Reduce the number of devices from the network that allows one token packet to be circulated in a predetermined order between multiple devices existing on the cyclic network so that only the device that receives the token packet can send data to the network. Network construction method when
A step of removing a device from the network, a step of broadcasting a reduction notification packet for notifying that the device that has been removed or the device in the previous stage has been removed from the network, and
Each device that has received the reduction notification packet deletes and updates the address of the reduced device held by each device, and
When the next device is explicitly removed for the device itself, the next device autonomously generates a reduction notification packet, broadcasts it to the entire network, and transmits a token packet to the next device. As a result, the packet transmission / reception control unit of the device itself sets the address of the device in the next stage of the address holding unit holding the address of the device in the previous stage, the next stage, and the next stage to the next stage based on itself. The process of updating to the device address
When the next device is unexpectedly removed for the device itself, the device itself autonomously generates a removal notification packet on behalf of the next device and broadcasts the generated reduction notification packet. And sending a token packet to the next-stage device,
A network construction method characterized by comprising:

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