JP6008761B2 - Independent distributed network system - Google Patents

Description

  The present invention relates to a self-supporting distributed network system in which, for example, in a AMI (Advanced Metering Infrastructure) communication system, when a relay device becomes unable to communicate or recovers from the inability to communicate, a node independently constructs a network. .

  Conventionally, an AMI communication system has been studied in order to realize a smart grid. The AMI communication system automatically installs an electronic power meter with a communication function at each low-voltage consumer's house, collects data such as the amount of power acquired over the network, and performs monitoring and control. This is a meter reading communication system. Such an AMI communication system is an autonomous distributed network system configured by a control server, a relay device, and a node. The nodes belong to a relay device network managed by the relay device, and each node can construct a route with other nodes based on its own judgment. The control server controls operations of the plurality of relay devices. As techniques used in such a self-sustained distributed network system, techniques disclosed in Patent Documents 1 and 2 shown below have been known.

  Patent Document 1 discloses a technique in which a main system GW (Gate Way) 1 and a standby system GW 2 transmit and receive heartbeat packets that can reach networks having different IP address prefixes, and synchronize IPsec information as necessary. Is disclosed.

  Patent Document 2 discloses an ATM network in which information about connections and networks is distributed and managed in each exchange, and each exchange manages network resources using a management connection provided between them. . In this ATM network, the step of detecting a connection failure by the exchange and the recovery of the management connection that has failed in accordance with the remedy procedure at the time of failure determined corresponding to the failure location are performed in an autonomous and distributed manner.

JP 2011-166245 A JP-A-7-115420

  By the way, an abnormality may occur in the relay device network and the relay device used in the autonomous distributed network system, and the relay device may be unable to communicate with other relay devices. In this case, after each node autonomously changes the route, the network is reconstructed by connecting the route to another relay device, and the operation of the entire communication system is continued. However, with the conventional self-sustained path construction function, after each node knows that the relay device has become unable to communicate, each node confirms a switchable path with the other nodes and reconstructs the network. It took time to complete.

  In the technique disclosed in Patent Document 1, the main system and the standby GW must be arranged in the network, and the cost required for installation and operation is doubled. In addition, complicated settings must be applied to the two GWs, and simple operation is difficult.

  Furthermore, in the technique disclosed in Patent Document 2, when a relay device having a plurality of nodes fails, a node connected to the relay device is a network configured by nodes connected to other relay devices. Could not enter.

  The present invention has been made in view of such a situation, and when one relay device becomes incapable of communication, a node belonging to the relay device network of one relay device promptly uses another relay device. The purpose is to enable entry into a relay device network.

The self-supporting distributed network system according to the present invention includes a control server that manages a network, a plurality of relay devices that are connected to the control server via a trunk network and communicate information with the control server, and nodes.
This node is connected by a branch network under the control of a plurality of relay devices, and independently constructs a relay device network managed by the relay device.
Control server and abnormality occurs to one trunk network relay device and is connected to the case in which one of the relay devices, Do that abnormal incommunicable occurs the control server, or another relay apparatus, a communication failure The relay device is connected to a node belonging to the relay device network of the relay device at a timing different from the timing at which the communication information is periodically transmitted using the overall delivery communication. A node belonging to the relay device network of one relay device, including communication information including relay device information including information indicating the state of the relay device propagating between the relay device and the node together with abnormality information indicating that communication is impossible. Propagate to.
A node belonging to the relay device network of one relay device performs the following operation.
Unlike the communication information that is periodically received , this node is information on the time when one relay device has become unable to communicate, communication information used in the relay device network of one relay device, and the relay device of one relay device The priority conditions include the communication quality of the relay device network of the other relay device and the number of nodes under the control of the other relay device to select the relay device network of the other relay device that the node belonging to the network requests to join. It will receive the relay device information including anomaly information to the node belonging to the relay device network of another relay device, to request entry into the relay device network of another relay device.
When entry is permitted, the fact that the node belonging to the relay device network of one relay device belonged to the relay device network of one relay device is saved, and the node to the relay device network of another relay device is saved. Switch to the communication setting and enter the relay device network of another relay device .
When one relay device that has malfunctioned is restored, the one relay device that has been restored serves as the recovery information indicating that one relay device has been restored. Review conditions for a node that has entered the relay device network of another relay device from the relay device network of the one relay device in which the error occurred to select the recovered relay device network of the one relay device when the device was restored Is transmitted to other relay devices and nodes.
When a node that has entered the relay device network of another relay device from the relay device network of one relay device in which an error has occurred receives the recovered relay device information, it enters the relay device network of the restored one relay device. Is switched to the communication setting of one relay device to the relay device network, and enters the relay device network of the restored one relay device from the relay device network of the other relay device.

  According to the present invention, it is possible to quickly transmit abnormality information to a node belonging to the relay device network of the relay device that has become unable to communicate, and this node can enter another relay device network. For this reason, the node can quickly rebuild the relay device network and continue the operation of the entire autonomous distributed network system.

1 is a network configuration diagram of an autonomous distributed network system according to a first exemplary embodiment of the present invention. FIG. It is explanatory drawing which shows the structural example of the Hello packet which concerns on the 1st Example of this invention. It is explanatory drawing which shows the structural example of the failure relay apparatus information packed in the blank field of the Hello packet which concerns on the 1st Example of this invention. It is a network block diagram of the self-supporting distributed network system when the second relay apparatus according to the first embodiment of the present invention fails. It is a network block diagram which shows the example which each node under the normal relay apparatus based on the 1st Example of this invention transmits a Hello packet. It is a flowchart which shows the example of a process in which the node which belongs to the relay apparatus network of the failed relay apparatus in the 1st Example of this invention makes a joining request to another relay apparatus network. FIG. 7 is a network configuration diagram illustrating an example of a first relay device network that is newly constructed as a result of the node in the first exemplary embodiment of the present invention performing the entry request processing illustrated in FIG. 6. It is a network block diagram of the self-supporting distributed network system which concerns on the 2nd Example of this invention. It is explanatory drawing which shows the structural example of the recovery relay apparatus information packed in the blank field of the Hello packet which concerns on the 2nd Example of this invention. It is a network block diagram which shows the example which propagates recovery relay apparatus information to each node using the Hello packet which concerns on the 2nd Example of this invention. It is a network block diagram which shows the example which propagates recovery relay apparatus information to each node using the unicast communication which concerns on the 2nd Example of this invention. It is a network block diagram which shows the example which propagates recovery relay apparatus information to each node using the multicast communication based on the 2nd Example of this invention. It is a network block diagram which shows the example which propagates recovery relay apparatus information to each node using the whole delivery communication packet based on the 2nd Example of this invention. It is a flowchart which shows the process example in which the node in the 2nd Example of this invention reconfigure | reconstructs a network. It is a network block diagram of the self-supporting distributed network system 1 which concerns on the 3rd Example of this invention. It is explanatory drawing which shows the structural example of the recovery relay apparatus information packed in the blank field of the Hello packet which concerns on the 3rd Example of this invention.

<1. First Embodiment>
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS.
The self-supporting distributed network system 1 to which the present invention is applied realizes a network construction method that is performed in cooperation with each node and relay device described later, by a computer executing a program. In the present specification and drawings, components having substantially the same function or configuration are denoted by the same reference numerals, and redundant description is omitted.

  FIG. 1 is a network configuration diagram of an autonomous distributed network system 1 according to a first embodiment of the present invention.

  The autonomous distributed network system 1 includes a control server 2 that manages a network constructed in the autonomous distributed network system 1. In addition, the first relay device 4 to the third relay device 6 that are connected to the control server 2 via the trunk network 3 and communicate information with the control server 2 (if the relay devices are not distinguished, “each relay device” Abbreviated as above). In addition, nodes n1 to n10 that are independently connected to each other via a branch network 7 under the control of a plurality of relay devices and that independently construct a relay device network managed by each relay device are provided.

  The control server 2 controls the operations of the first relay device 4 to the third relay device 6 and the communication status of the first relay device network 11 to the third relay device network 13 built in the self-supporting distributed network system 1. Etc. are managed.

  The first relay device 4 manages the first relay device network 11 to which the nodes n1 to n4 belong. The second relay device 5 manages the second relay device network 12 to which the nodes n5 to n8 belong. The third relay device 6 manages the third relay device network 13 to which the nodes n9 and n10 belong. Nodes n1 to n10 (abbreviated as “each node” when the nodes are not distinguished) are connected by a branch network 7 under the control of each relay device. Each node autonomously constructs the first relay device network 11 to the third relay device network 13 managed by the first relay device 4 to the third relay device 6, respectively, and belongs to the relay device network. Communication with each node is realized.

  Next, when one of the first relay device 4 to the third relay device 6 fails, the node belonging to the relay device network of the failed relay device becomes independent and reconstructs the network with other relay devices. A process for continuing communication over the entire network will be described.

  As described above, each node is assumed to be able to establish a self-sustained path configuration with another node without receiving an instruction from the relay device. Each node satisfies a certain condition when any relay device in the network fails and becomes unable to communicate (eg, when the node cannot receive a message from the relay device for 2 hours or more) ), An abnormality occurring in the communication path with the relay device is detected. Each node that has detected an abnormality scans the communication status of other nodes arranged around the node itself.

  In the following description, it is assumed that the second relay device 5 is out of order and cannot communicate with other relay devices. At this time, the nodes n5 to n8 belonging to the second relay device network 12 are connected to a relay device network of another relay device (the first relay device 4 or the third relay device 6) different from the failed second relay device 5. Can communicate with the node to which it belongs. Then, the operation of the entire autonomous distributed network system 1 is continued by joining a node belonging to the second relay device network 12 to another relay device network different from the second relay device network 12. It was.

  However, it takes time for a node belonging to the relay device network of the failed relay device to detect that the relay device has failed. For this reason, a node belonging to the relay device network of the failed relay device becomes unable to communicate with other nodes belonging to the relay device network of the normal relay device or the normal relay device, and the autonomous distributed network system The entire operation of 1 may be delayed.

  For this reason, it is assumed that the time taken for the node belonging to the relay device network of the failed relay device to detect the failure of the relay device is shortened using the method described below. Then, a node belonging to the relay device network of the failed relay device promptly enters the relay device network of another normal relay device so that the operation of the autonomous distributed network system 1 is continued.

  Hereinafter, when the second relay device 5 fails and the nodes n5 to n8 belonging to the second relay device network 12 cannot communicate with the second relay device 5, how are the nodes n5 to n8 It will be described whether an abnormality of the relay device 5 is detected and another relay device network is entered.

First, the Hello packet used in the autonomous distributed network system 1 will be described.
FIG. 2 is an explanatory diagram illustrating a configuration example of a Hello packet.

  There is a Hello packet as an example of communication information in which each relay device periodically notifies the other relay devices of the status of its own device to other relay devices, the control server 2, nodes, and the like. This Hello packet includes a local terminal information field h1, a relay device information field h2, a time information field h3, a route information field h4, a communication setting information field h5, a system information field h6, and a blank field h7.

The own terminal information field h1 includes unique information such as the device ID of the relay device, the node ID of the node, and the MAC ID of the relay device or node that is the transmission source of the Hello packet.
The relay device information field h2 includes information such as the device ID of the relay device, the MAC ID, and the number of nodes belonging to the relay device network.
The time information field h3 includes time information at the time of transmission of the Hello packet.

The route information field h4 includes information such as route version and communication quality.
The communication setting information field h5 includes information such as a communication channel that is uniquely set for identifying each relay device network.
The system information field h6 includes information such as the maximum number of hops and the number of retransmissions until communication with the relay apparatus in the relay apparatus network to which the node belongs.
The blank field h7 is filled with failure relay device information i1 (see FIG. 3) to be described later.

  FIG. 3 is an explanatory diagram showing a configuration example of failure relay device information packed in the blank field h7 of the Hello packet. The upper part of the table shown in FIG. 3 shows message information types, and the lower part of the table shows specific examples of parameters stored in each information type.

  Various types of information such as failure relay device information i1 including information of the failed relay device, failure relay device communication information i2 including communication setting information of the failed relay device, and an instruction parameter i3 indicating an instruction parameter to the node as the information type There is. These pieces of abnormality information packed in the blank field h7 are collectively referred to as “failure relay device information”.

The failure relay device information i1 includes information on the device ID of the failed second relay device 5 and the time when the second relay device 5 has failed and the second relay device 5 has become unable to communicate.
The failure relay device communication information i2 includes communication channel information as communication information used in the second relay device network 12 of the failed second relay device 5. This communication channel is a value assigned individually for each relay device network.
The instruction parameter i3 includes first and second priority conditions for selecting relay device networks of other relay devices that nodes n5 to n8 belonging to the second relay device network 12 request to join. The first priority condition is that the communication quality of the network is good, and the second priority condition is that the number of nodes belonging to the relay device network is equal to or less than the maximum number of nodes.

Next, a method in which the nodes n5 to n8 belonging to the failed second relay device 5 enter the first relay device network 11 of the first relay device 4 operating normally will be described.
FIG. 4 is a network configuration diagram of the autonomous distributed network system 1 when the second relay device 5 fails.

All the relay apparatuses monitor each other for abnormality, and when an abnormality occurs in the second relay apparatus 5, other relay apparatuses are connected to the nodes n5 to n8 belonging to the second relay apparatus network 12 of the second relay apparatus 5. On the other hand, fault relay device information including abnormality information is propagated.
All the relay devices and the control server 2 monitor each other for abnormality. And when abnormality arises in the 2nd relay apparatus 5, the control server 2 is connected with respect to the nodes n5-n8 which belong to the 2nd relay apparatus network 12 of the 2nd relay apparatus 5 via another relay apparatus. The failure relay device information including the abnormality information is propagated.

  For example, the control server 2 and each relay device periodically transmit a Hello packet to a subordinate node or another relay device on a regular basis (for example, once every 30 minutes). The relay device abnormality is monitored. Each relay apparatus transmits a Hello packet to other relay apparatuses and nodes once every 30 minutes, for example.

  By the way, when the second relay device 5 breaks down, the second relay device 5 includes nodes n5 to n8 in the second relay device network 12 and other relay devices (the first relay device 4 and the third relay device 6). The Hello packet cannot be transmitted to the control server 2. When the control server 2, the first relay device 4, and the third relay device 6 cannot receive the Hello packet from the second relay device 5, the second relay device 5 breaks down and the second relay device 5 It is detected that communication with the relay device or the control server 2 is impossible.

  At this time, the normal first relay device 4 transmits, to the subordinate nodes n1 to n4, the Hello packet p1 in which the failure relay device information (see FIG. 3) is packed in the blank field h7. Similarly, the normal third relay device 6 transmits to the subordinate nodes n9 and n10 the Hello packet p1 in which the failure relay device information is packed in the blank field h7.

  As described above, the Hello packet is a packet that is normally used for monitoring each other for an abnormality of the relay device. For this reason, even if the failure relay device information is put on the Hello packet p1, the information of the failed second relay device 5 is propagated to each node belonging to the autonomous distributed network system 1 without increasing the network load. be able to. Note that the nodes n5 to n8 belonging to the second relay device network 12 cannot receive the Hello packet p1 because the communication settings are different from those of other relay device networks.

  FIG. 5 is a network configuration diagram showing an example in which each node under the normal relay device transmits a Hello packet p2.

  When the second relay device 5 becomes unable to communicate with the control server 2 or another relay device, the nodes n1 to n4 read the failure relay device information from the Hello packet p1 received from the first relay device 4. Similarly, the nodes n9 and n10 read out the failure relay device information from the Hello packet p1 received from the third relay device 6. Then, the nodes n1 to n4, n9, and n10 temporarily change the communication setting to the communication channel used by the second relay device 5 that is stored in the failure relay device communication information i2. The timing for changing the communication setting is not affected by the communication of the autonomous distributed network system 1 and is different from the timing for transmitting the normal Hello packet p1 (for example, once every 30 minutes). As an example of this timing, for example, when the Hello packet p1 is transmitted once every 30 minutes from 14:00, the communication setting is made at a timing different from the Hello packet p1 such as 14:35, 15: 5. (For example, a communication channel) is changed.

  Thereafter, the nodes n1 to n4 belonging to the first relay device network 11 and the nodes n9 and n10 belonging to the third relay device network 13 are received by the nodes n5 to n8 belonging to the second relay device network 12. Packet p2 is transmitted. Unlike the Hello packet p1 that is periodically received, the Hello packet p2 includes abnormality information indicating that the second relay device 5 cannot communicate. When the transmission of the Hello packet p2 is completed, the nodes n1 to n4, n9, and n10 return to the original communication settings.

The nodes n5 to n8 belonging to the second relay device network 12 of the second relay device 5 that has become unable to communicate receive the Hello packet p2 from the nodes n1 to n4, n9, and n10. Then, the nodes n5 to n8 read relay device information including information indicating the state of the relay device propagating between the relay device and the node from the received Hello packet p2. After that, the nodes n5 to n8 request the nodes belonging to the relay device network of other relay devices to enter the relay device network of other relay devices independently. Then, the second relay device network 12 of the second relay device 5 enters the relay device network of another relay device.
Hereinafter, an example of processing for entering the relay device network of another relay device will be described using the node n6 as an example.

  If the node n3 is the node n3 having the highest priority from the instruction parameter i3 to the node read from the received Hello packet p2, the node n6 passes through the node n3 and the first relay device of the first relay device 4 An entry request is made to the network 11.

Here, a process in which the node n6 makes a request to enter the first relay device network 11 will be described.
FIG. 6 is a flowchart showing an example of processing in which the node n6 belonging to the second relay device network 12 of the failed second relay device 5 makes a request to enter another relay device network.

  As described above, when an abnormality occurs in the second relay device 5 and the second relay device 5 becomes unable to communicate with the control server 2 or other relay devices, the second relay device 5 can communicate with the control server 2 or other relay devices. A certain other relay apparatus transmits the Hello packet p2. The transmission of the Hello packet p2 including the abnormality information is performed at a timing different from the timing of transmitting the Hello packet p1 via a node belonging to the relay device network of another relay device. Then, the Hello packet p2 is propagated to the nodes n5 to n8 belonging to the second relay device network 12 of the second relay device 5.

  Then, the node n6 belonging to the second relay device network 12 reads the failure relay device information from the Hello packet p2 received from the node n3 belonging to the first relay device network 11 (step S1).

  Next, the node n6 determines whether or not the read failure relay device information includes failure information of the second relay device 5 to which it currently belongs (step S2). If the node n6 determines that the failure information of the second relay apparatus 5 to which it currently belongs is not included, the process is terminated. On the other hand, when the node n6 determines that the failure information of the second relay apparatus 5 to which the node n6 currently belongs is included, the node n6 reads the instruction parameter i3 from the Hello packet p2.

  Then, the node n6 performs a process of selecting a node of the first relay device network 11 that the node n6 intends to enter in accordance with the condition of the instruction parameter i3. Here, it is assumed that the node n3 is selected. In accordance with this process, the node n6 changes its own communication setting to the communication setting of the first relay device network 11 used by the node n3 (step S3).

  Next, since the node n6 is independent and requests entry of another relay device into the relay device network, the first relay device network is assigned to the node n3 belonging to the first relay device network 11 to be entered. 11 is transmitted (step S4). The entry request message is sent from the node n3 to the first relay device 4 via the node n1, and the first relay device 4 determines whether or not the node n6 can join. After determining whether or not entry is possible, the first relay device 4 transmits an entry response message, and this entry response message is sent to the node n6 via the nodes n1 and n3.

  Therefore, the node n6 determines whether or not an entry response message has been received from the node n3 (step S5). When the node n6 receives the entry response message from the node n3, the node n6 determines whether or not the content of the entry response message permits entry into the first relay device network 11 (step S6).

  In step S6, when the content of the entry response message is such that the node n6 does not permit entry into the first relay device network 11, the node n6 returns to step S3. Then, according to the second priority condition of the instruction parameter i3, another node is selected, another node is selected, and the processing of steps S3 to S6 is repeated to request entry to another relay device network that can be entered. to continue.

  On the other hand, if the content of the entry response message permits entry into the first relay device network 11 in step S6, the node belonging to the second relay device network 12 is assigned to the past relay device network. Is stored (step S7). This affiliation information includes, for example, relay device information of a relay device that is higher in the relay device network to which the node belongs, the number of hops until communication with the relay device in the relay device network to which the node belongs, and relay There is past relay device information including communication quality in the device network. This affiliation information is used by the node n6 to reconstruct the route to the original second relay device network 12 when the second relay device 5 recovers from the failure.

  Then, the node n6 switches its communication setting information to the communication setting used by the first relay device network 11 (step S7). Thereby, since the node n6 completes entry into the first relay device network 11, the process is terminated.

  In step S5, when the node n6 does not receive the entry response message from the node n3, the node n6 determines whether a certain time (for example, 2 hours) has elapsed since the node n6 transmitted the entry request message to the node n3. (Step S8). If the predetermined time has not elapsed, the node n6 returns to step S5 and continues to wait for reception of the entry response message.

  In step S8, when a predetermined time has elapsed without transmitting an entry request message to the node n3 and receiving an entry response message, the node n6 further determines whether an end condition is satisfied (step S9). For example, the termination condition is that 24 hours have passed since the entry request message was transmitted and no entry response message was received.

  If the end condition is satisfied, the node n6 ends the process. On the other hand, if the termination condition is not satisfied, the process returns to step S3, selects another node, and continues to request entry into another relay device network.

  As described above, when the entry request to the first relay device network 11 fails, the node n6 can enter the network by requesting the next highest priority node (for example, the node n1). This process is repeated in descending order of priority.

  FIG. 7 is a network configuration diagram showing an example of the first relay device network 14 newly constructed as a result of the node performing the entry request processing shown in FIG.

  The nodes n5 and n6 leave the affiliation of the second relay device network 12 and enter the first relay device network 11. As a result, the first relay device 4 forms a first relay device network 14 to which the nodes n1 to n6 belong.

  Further, the nodes n7 and n8 leave the affiliation of the second relay device network 12 and enter the third relay device network 13. As a result, the third relay device 6 constitutes a third relay device network 15 to which the nodes n7 to n10 belong.

  Thus, even if the nodes n5 to n8 belonging to the second relay device network 12 fail to transmit / receive data to / from the control server 2 due to the failure of the second relay device 5, they enter another relay device network. Thus, the relay device network can be reconstructed. For this reason, the time during which data cannot be transmitted and received between nodes can be shortened as much as possible.

  According to the self-sustained distributed network system 1 according to the first embodiment described above, the node under the faulty relay device receives from the nodes under the normal relay device around this node. The failure relay device information is read from the Hello packet p2. The Hello packet p2 is normally transmitted at a transmission timing different from that of the Hello packet communicated over the network. For this reason, since the Hello packet p2 is transmitted not at a normal timing but at a timing different from the normal time, it is possible to reduce the time taken for each node to detect an abnormality occurring in the relay device.

  Further, when the nodes n5 to n8 under the failed second relay device 5 determine that the second relay device 5 has failed, other nodes under the normal other relay device have another The process of entering the relay device network is performed autonomously. For this reason, the load for constructing a new network is distributed from each relay apparatus to each node. Thereby, the relay device only needs to perform the minimum processing for configuring its own relay device network, and the cost of network construction can be suppressed. Further, the first relay device network 11 and the second relay device network 12 shown in FIG. 1 are reconstructed into the first relay device network 14 and the third relay device network 15 shown in FIG. The operation of the network system 1 can be continued.

  In addition, the self-supporting distributed network system 1 prepares two expensive relay devices such as a primary system and a secondary system, and when a failure occurs in the primary system, the operation is continued by switching to the secondary system. It is not intended. For this reason, it is not necessary to make detailed settings for both the primary and secondary relay apparatuses and perform switching operation, and the operation load of the autonomous distributed network system 1 is reduced.

<2. Second Embodiment>
Next, after the nodes n5 to n8 autonomously enter another relay device network as shown in FIG. 7, when the second relay device 5 recovers from the failure, the changed network configuration is restored to the original. A method for rebuilding the network configuration will be described.

  As described above, it is assumed that the relay device is abnormal and the network is reconstructed. After this, even if the failed relay device is recovered, the network has already been reconstructed, so that the network configuration before the occurrence of the abnormality in the relay device does not return autonomously. For this reason, the reconstructed network may continue communication on a non-optimal communication path. In this case, the relay device recovered from the failure remains unused, and the load concentrated on the specific relay device may not be eliminated.

  The autonomous distributed network system 1 according to the second embodiment described below returns to the original network configuration after the second relay device 5 is restored. That is, when the second relay device 5 in which an abnormality has occurred is recovered, the recovered second relay device 5 includes the recovery information indicating that the second relay device 5 has been recovered in the relay device information. To the relay device and node. After that, when the node that has entered the relay device network of another relay device receives the recovery relay device information, it independently requests the restored second relay device 5 to enter the relay device network. Then, the node that has requested entry enters the relay device network of the restored second relay device 5 from the relay device network of another relay device.

  At this time, the nodes n5 to n8 receive the message including the instruction parameter i5 (see FIG. 8 to be described later) in order to determine the information of the restored second relay device 5 and whether to perform network reconstruction. . Each of the nodes n5 to n8 compares the instruction parameter i5 set in the message with the information indicating that it belongs to the second relay device network 12 of the second relay device 5 before the abnormality that has been stored in advance has occurred. To do. Then, the nodes n5 to n8 reconstruct the network under advantageous conditions based on the compared information.

  FIG. 8 is a network configuration diagram of the self-supporting distributed network system 1 according to the second exemplary embodiment of the present invention.

  Even if the second relay device 5 recovered from the failure resumes communication with another relay device or the control server 2, the nodes n5 to n8 that belonged to the second relay device 5 in the past have already been combined with the nodes n1 to n4. A first relay device network 14 is constructed. For this reason, the node does not belong to the second relay device network 16, and the second relay device 5 and the nodes n5 to n8 cannot communicate with each other.

  Therefore, if the state shown in FIG. 7 continues, two relay devices (first relay device) are prepared despite the provision of three relay devices (first relay device 4 to third relay device 6). 4 and the third relay device 6). For this reason, the load is concentrated on the two relay apparatuses, which may cause data processing, communication delay, and the like. Here, the autonomous distributed network system 1 performs processing for reconstructing the relay device network by filling the blank field h7 of the Hello packet with the recovery relay device information as shown in FIG.

  FIG. 9 is an explanatory diagram showing a configuration example of the recovery relay device information packed in the blank field h7 of the Hello packet. The upper part of the table shown in FIG. 9 shows message information types, and the lower part of the table shows specific examples of parameters stored in each information type.

  As the information type, in addition to the failure relay device information i1 shown in FIG. 3, various information such as the recovery relay device information i4 including the recovery information of the relay device recovered from the failure and the instruction parameter i5 indicating the instruction parameter to the node Such information is collectively referred to as “recovery relay device information”. The recovery relay device information may include information indicating that the second relay device 5 has been replaced.

The recovery relay device information i4 includes information on the device ID of the second relay device 5 recovered from the failure, the time when the abnormality occurred in the second relay device 5, and the time when the second relay device 5 was recovered.
The instruction parameter i5 selects a restored relay device network of the second relay device 5 by a node that has entered the relay device network of another relay device from the second relay device network 12 of the second relay device 5 in which an abnormality has occurred. For the first and second review conditions and the review time. The first review condition is that the node previously belonged to the relay device network of the restored relay device, and the second review condition is that the communication quality is good. The review time is that a predetermined time (for example, 3 hours) has elapsed since the relay device recovered from the failure.

  Then, using any of the following four methods shown in FIGS. 10 to 13, the failure relay device information shown in FIG. 9 is added to the nodes that belonged to the relay device network of the restored relay device in the past. Propagate it.

[(1) Method using Hello packet]
FIG. 10 is a network configuration diagram illustrating an example in which the recovery relay device information is propagated to each node using the Hello packet p3.

The first relay device 4 and the third relay device 6 include the recovery relay device information in the blank field h7 of the Hello packet p3. And it transmits to each node which belongs to the 1st relay apparatus network 14 and the 3rd relay apparatus network 15 at the timing which transmits communication information regularly. The Hello packet p3 has the same field configuration as the Hello packet shown in FIG. 2 described above, and the recovery relay device information is added to the blank field h7 of the Hello packet p3. Thereby, it is possible to make a network reconstruction request to all nodes without increasing the network bandwidth load.
In the example shown in FIG. 10, all the nodes n1 to n10 are targets for network reconstruction.

[(2) Method using unicast communication]
FIG. 11 is a network configuration diagram illustrating an example in which the recovery relay device information is propagated to a specific node using the unicast communication packet p4.

The control server 2 transmits the recovery relay apparatus information to a specific node belonging to the relay apparatus network of another relay apparatus using unicast communication. For example, the control server 2 transmits the unicast communication packet p4 only to the node n5 via the first relay device 4 and propagates the recovery relay device information. Using unicast communication in this way is useful when changing the network configuration of a specific node (currently, node n5).
In the example shown in FIG. 11, only the node n5 is a target for network reconstruction.

[(3) Method using multicast communication]
FIG. 12 is a network configuration diagram illustrating an example in which the recovery relay device information is propagated to a specific node group using the multicast communication packet p5.

The control server 2 transmits the recovery relay device information to a node group belonging to a specific relay device network of another relay device using multicast communication. For example, the control server 2 transmits the multicast communication packet p5 to the node group belonging to the third relay device network 15 via the third relay device 6, and propagates the recovery relay device information. The use of multicast communication in this way is useful when changing the network configuration of a specific node group (this time, nodes n7 to n10).
In the example illustrated in FIG. 12, the nodes n7 to n10 are targets for network reconstruction.

[(4) Method using whole distribution communication]
FIG. 13 is a network configuration diagram illustrating an example in which the recovery relay device information is propagated to all nodes using the overall delivery communication packet p6.

  The first relay device 4 and the third relay device 6 send the recovery relay device information to the relay device network of another relay device at a timing different from the timing at which the communication information is periodically transmitted using the overall delivery communication. Send to the node to which it belongs. For example, the first relay device 4 transmits the entire delivery communication packet p6 to the nodes n1 to n6 that are nodes belonging to the first relay device network 14. The third relay device 6 transmits the entire distribution communication packet p6 to the nodes n7 to n10 that are nodes belonging to the third relay device network 15. Then, the recovery relay device information is propagated to the nodes n1 to n10. In the method of transmitting the entire delivery communication packet p6, (1) As in the method using the Hello packet, the recovery relay device information is propagated to all the nodes in the relay device network and the network is requested to be reconstructed. be able to.

  When using the entire distribution communication, (1) the number of packets in the network increases as compared with the method using the Hello packet, but the recovery relay device information can be propagated faster. Therefore, it is effective when it is desired to immediately review the entire network configuration for all the nodes n1 to n10. In the example of FIG. 9, all the nodes n1 to n10 are targets to be reconstructed, but it is also possible to perform overall delivery communication to nodes under the control of a specific relay device.

  Thus, the node that has received the recovery relay device information transmitted using any one of the methods shown in (1) to (4) reconstructs the network.

  FIG. 14 is a flowchart illustrating a processing example in which a node reconstructs a network. Here, (1) a processing example in which the node n6 reconstructs a network using a method using a Hello packet will be described.

  First, the node n6 reads the recovery relay device information from the Hello packet p3 received from the node n3 (step S11). Then, the node n6 determines whether or not it is restoration relay device information indicating that the first relay device 4 having the node of the relay device network to which it currently belongs has been restored (step S12). If it is the recovery relay device information of the first relay device 4, the process is terminated.

  If it is not the recovery relay device information of the first relay device 4, the node n6 has the first review condition of the instruction parameter i5 shown in FIG. 9 is true, that is, the node n6 has been the second relay of the second relay device 5 in the past. It is determined whether the user belongs to the device network 12 (step S13). If the first review condition is false, that is, if the node n6 has not belonged to the second relay device network 12 in the past, the processing is terminated.

  If the first review condition is true, the node n6 changes to the communication setting of the second relay device 5 recovered from the failure (step S14). Then, the node n6 determines whether or not the Hello packet p3 has been received from a node around the node n6 (this time, the node n3) after a predetermined time (for example, 30 minutes) has elapsed (step S15).

  In step S15, it is assumed that the node n6 receives the Hello packet p3 from the node n3 after a predetermined time has elapsed. At this time, in the node n6, the second relay device network 16 of the restored second relay device 5 is subjected to the second review of the instruction parameter i5 than the first relay device network 14 to which the current node n6 belongs. It is determined whether the condition is met (step S16). That is, the node n6 determines whether the communication quality of the second relay device network 16 is better than that of the first relay device network 14.

  In step S16, when the second relay device network 16 meets the second review condition, the node n6 performs a process of entering the second relay device network 16 under the restored second relay device 5 ( Step S17). Then, the node n6 determines whether the entry into the second relay device network 16 has been successful (step S18). If the entry to the second relay device network 16 is successful, the process is terminated.

  However, if the node n6 does not receive the Hello packet p3 in step S15, the second relay device network 16 may not meet the second review condition in step S16. In addition, in step S18, entry into the second relay device network 16 may not be successful. In these cases, the node n6 determines whether or not the review time specified in the instruction parameter i5 has elapsed (step S19).

  If the review time has not elapsed, the process returns to step S15, and the node n6 continues to wait for the reception of the Hello packet p3 from a node other than the node n3. On the other hand, if the review time has elapsed, the node n6 restores the changed communication setting (step S20) and continues to belong to the first relay device network 14.

  According to the self-sustained distributed network system 1 according to the second embodiment described above, even if a node that was under a faulty relay device enters a relay device network under another relay device, After the failed relay device is restored, the node is urged to reconfigure the network. As a result, a node that previously belonged to the relay device network of the failed relay device can autonomously return to the original relay device network. For this reason, after restoring a failed relay device, an engineer goes to the location where the node is set, and there is no need to change the communication settings to allow the node to enter the relay device network of the restored relay device. The operational load on the network is reduced. In addition, it is possible to shorten the communication failure time during which the node having reconstructed the network cannot communicate with other nodes, and to continue the operation of the autonomous distributed network system 1.

  In addition, since the network is reconstructed along with the recovery of the relay device, it is possible to reduce the load on the other relay device that was loaded while the relay device failed. For this reason, the communication load can be optimized as the entire autonomous distributed network system 1.

  Depending on the setting of the instruction parameter i5, the network configuration can be controlled under conditions such as “including nodes that have not belonged to the faulty relay device in the past” and “all nodes belonging to the faulty relay device”. . Even when the relay device is replaced with a relay device different from the failed second relay device 5, the information of the replaced relay device is included in the recovery relay device information, so that the failure relay device is recovered. It is possible to realize control to reconfigure the network configuration.

<3. Third Embodiment>
Next, a method for reconstructing a network when a failure occurs in the main network 3 provided between each relay device and the control server 2 will be described with reference to FIGS. 15 and 16.

  FIG. 15 is a network configuration diagram of the autonomous distributed network system 1 according to the third exemplary embodiment of the present invention.

  It is assumed that there is no abnormality in the control server 2 and the second relay device 5 shown in FIG. However, it is assumed that an abnormality occurs in the trunk network 3 to which the control server 2 and the second relay device 5 are connected, and the second relay device 5 becomes unable to communicate with the control server 2 or other relay devices.

  At this time, the second relay device 5 can operate normally and can communicate with the nodes n5 to n8 belonging to the second relay device network 12. For this reason, abnormality information is transmitted at a timing different from the timing at which the second relay device 5 periodically transmits communication information to the nodes n5 to n8 belonging to the second relay device network 12 of the second relay device 5. Is propagated. As a result, the nodes n5 to n8 reduce the time for each node to detect that the second relay device 5 cannot communicate, and the operation of the autonomous distributed network system 1 is more efficient than the first embodiment. Can continue.

  FIG. 16 is an explanatory diagram of a configuration example of the recovery relay device information packed in the blank field h7 of the Hello packet. The upper part of the table shown in FIG. 9 shows message information types, and the lower part of the table shows specific examples of parameters stored in each information type.

As the information type, there are various information such as an instruction parameter i6 indicating an instruction parameter to the node in addition to the failure relay apparatus information i1 shown in FIG.
The instruction parameter i6 includes a first priority condition for selecting another relay device and entering the relay device network when a failure occurs in the main line network 3. The instruction parameter i6 includes a communication setting for entering another relay device network when there is no node that can enter the relay device network.
The first priority condition is that the communication quality of the other relay device network that the node intends to enter is good. And the communication setting for entering into another relay apparatus network includes the communication setting including the communication channel of the 3rd relay apparatus network 13, etc., for example.

Next, returning to FIG. 15, the operation of the second relay device 5 will be described.
The second relay device 5 monitors the control server 2, the first relay device 4, and the third relay device 6 for abnormality. When abnormality monitoring is interrupted, it is detected that an abnormality has occurred in any one of the control server 2, the first relay device 4, or the third relay device 6.

  When an abnormality occurs in the main line network 3, the control server 2 and the second relay device 5 cannot communicate with each other. For this reason, the nodes n5 to n8 belonging to the second relay device network 12 cannot communicate with the control server 2. That is, normal operation cannot be performed as the self-supporting distributed network system 1.

  For this reason, the second relay device 5 transmits the relay device information including the abnormality information to the second relay device 5 at a timing different from the timing at which the relay device information is periodically transmitted using the overall delivery communication. Transmit to a node belonging to the relay device network 12. For example, the second relay device 5 transmits the entire delivery communication packet p6 including the failure relay device information illustrated in FIG. 16 to the nodes n5 to n8 belonging to the second relay device network 12. Thus, the nodes n5 to n8 can recognize that an abnormality has occurred in the main line network 3.

  The nodes n5 to n8 that have received the failure relay device information and recognized that the communication of the second relay device 5 is impossible are performed via the high priority node according to the first priority condition included in the instruction parameter i6. Requests to enter the relay device network. Then, when entry is permitted, the nodes n5 to n8 store that they belonged to the second relay device network 12, and switch to the communication setting to the relay device network of other relay devices, Enter the relay device network of relay devices. In this way, the first relay device network 11 and the third relay device network 13 are reconstructed.

  Note that when an entry request cannot be made to a node of a relay device network with good communication quality, an operation of scanning communication of another relay device network is performed. However, by adding information of another relay device network (here, the third relay device network 13) to the instruction parameter i3, it is also possible to limit the scan target and find a relay device network that can be quickly entered. As a result, a node that detects an abnormality earlier than the autonomous distributed network system 1 according to the first embodiment makes an entry request to the relay device network, and the operation of the autonomous distributed network system 1 can be continued. it can.

  In the self-sustained distributed network system 1 according to the third embodiment described above, when an abnormality occurs in the trunk network 3, the second relay device 5 promptly contacts each node belonging to the second relay device network 12. The fault relay device information is propagated to. Each node that has received this fault relay device information can continue the operation of the entire autonomous distributed network system 1 by entering another relay device network and reconstructing the relay device network.

  Further, it is not necessary to set communication parameters in advance or perform initial setting of the communication system. Even if a relay device is added or removed, no particular work is required for the nodes belonging to the relay device network.

  In this self-sustained distributed network system 1, the entire delivery communication packet p6 including the recovery relay device information is transmitted to the node. However, as shown in the second embodiment, unicast communication or the like is used. Other communication methods may be used.

  In addition, each configuration, function, processing unit, and processing unit in the above-described embodiment may be realized by hardware by designing a part or all of them, for example, by an integrated circuit. Each of the above configurations, functions, and the like can be executed by software by the processor interpreting and executing a program that realizes each function. When a series of processing is executed by software, it can be executed by a computer in which a program constituting the software is incorporated in dedicated hardware or a computer in which programs for executing various functions are installed. . For example, a program constituting desired software may be installed and executed on a general-purpose personal computer or the like.

  Further, a recording medium on which information such as software programs, tables, and files for realizing the functions of the above-described embodiments may be supplied to the system or apparatus. It goes without saying that the function is also realized by reading and executing the program code stored in the recording medium by a computer (or a control device such as a CPU) of the system or apparatus.

  Examples of the recording medium for supplying the program code in this case include the following. For example, a flexible disk, hard disk, optical disk, SSD (Solid State Drive), magneto-optical disk, DVD, CD-ROM, CD-R, magnetic tape, nonvolatile memory card, ROM, or the like can be used.

  Further, the functions of the above-described embodiment are realized by executing the program code read by the computer. In addition, an OS or the like running on the computer performs part or all of the actual processing based on the instruction of the program code. The case where the function of the above-described embodiment is realized by the processing is also included.

Further, the present invention is not limited to the above-described embodiments, and various other application examples and modifications can be taken without departing from the gist of the present invention described in the claims.
For example, the above-described exemplary embodiments have been described in detail and specifically for easy understanding of the present disclosure, and are not necessarily limited to those having all the configurations described. Further, a part of the configuration of one embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of one embodiment. Moreover, it is also possible to add, delete, and replace other configurations for a part of the configuration of each embodiment.
In addition, the control lines and information lines are those that are considered necessary for the explanation, and not all the control lines and information lines on the product are necessarily shown. Actually, it may be considered that almost all the components are connected to each other.

  DESCRIPTION OF SYMBOLS 1 ... Autonomous distributed network system, 2 ... Control server, 3 ... Trunk network, 4-6 ... 1st relay apparatus-3rd relay apparatus, 7 ... Branch line network, 8 ... Trunk network, 11-13 ... 1st relay apparatus Network to third relay device network, n1 to n10... Node

Claims (10)

A control server that manages the network;
A plurality of relay devices connected to the control server via a trunk network and communicating information with the control server;
A node that is connected by a branch network under the plurality of relay devices and autonomously constructs a relay device network managed by the relay device; and
Abnormality occurs to the main line network and the control server and one of the relay devices are connected, if one of the relay device, abnormal Do that incommunicable has occurred with the control server or other of the relay devices In addition, the timing at which one relay device that has become unable to communicate periodically transmits communication information to the nodes belonging to the relay device network of the one relay device by using overall delivery communication. The communication information including relay device information including information indicating a state of the relay device that propagates between the relay device and the node together with abnormality information indicating that the one relay device cannot communicate at different timings Is propagated to a node belonging to the relay device network of the one relay device,
The nodes that belong to the relay device network one of the relay device, unlike the communication information received regularly one of the relay device the time information becomes unreachable, the relay device of one of the relay devices Relay of another relay device for selecting the communication information used in the network, the relay device network of another relay device that the node belonging to the relay device network of one relay device requests to join Receiving the relay device information including the abnormality information including the communication quality of the device network and the number of nodes under control of the other relay device as a priority condition, and for the nodes belonging to the relay device network of the other relay device Requesting other relay devices to enter the relay device network,
When entry is permitted, the fact that the node belonging to the relay device network of one of the relay devices belongs to the relay device network of one of the relay devices is stored, and the relay of the other relay device is saved Switch to the communication settings to the device network, enter the relay device network of the other relay device ,
When one of the relay devices in which an abnormality has occurred is restored, the time when the one relay device has malfunctioned as recovery information indicating that the one of the restored relay devices has been restored When the one relay device is restored, a node that has entered the relay device network of another relay device from the relay device network of the one relay device in which an abnormality has occurred is restored and the relay device of the one relay device is restored Propagate recovery relay device information including a review condition for selecting a network to the other relay device and the node,
When a node that has entered the relay device network of another relay device from the relay device network of the one relay device in which an abnormality has occurred receives the recovery relay device information, the relay device of the one relay device that has been recovered Request entry into the network, switch to the communication setting of one relay device to the relay device network, and enter the relay device network of the restored one relay device from the relay device network of the other relay device Independent distributed network system. When the one relay device becomes abnormal and the one relay device becomes unable to communicate with the control server or another relay device, the other one that can communicate with the control server or another relay device The relay device includes the abnormality information, and the relay device information is transmitted at a timing different from the timing at which the communication information is transmitted via a node belonging to the relay device network of the other relay device. Propagate to the node belonging to the relay device network of the relay device,
When the node belonging to the relay device network of one of the relay devices requests entry of the other relay device into the relay device network and entry is permitted,
The node belonging to the relay device network of one of the relay devices stores that it belongs to the relay device network of the one of the relay devices, and switches to the communication setting of the other relay device to the relay device network The self-sustained distributed network system according to claim 1, further entering a relay device network of the other relay device. All the relay devices monitor each other for an abnormality, and when an abnormality occurs in one of the relay devices, the other relay device is connected to the node belonging to the relay device network of the one relay device. The autonomous distributed network system according to claim 2 , wherein the relay device information including the abnormality information is propagated. All the relay devices and the control server monitor each other for abnormality, and when an abnormality occurs in one relay device, the control server belongs to the relay device network of the one relay device. The autonomous distributed network system according to claim 2 , wherein the relay device information including the abnormality information is propagated via the other relay device. The node is the relay device information of the relay device that is higher than the relay device network of the one relay device to which the node belongs, and the relay device network of the one relay device to which the node belongs. Storing past relay device information including the number of hops until communication with one relay device and communication quality in the relay device network of the one relay device;
When one of the relay devices is restored, the node is set to the message when receiving a message including information on the restored one of the relay devices and a parameter for determining whether to perform network reconstruction. 5. The autonomous distributed network system according to claim 3 , wherein the parameter is compared with information of the one relay device before occurrence of an abnormality that has been stored in advance, and the network is reconstructed based on the compared information. The other relay device includes the restoration relay device information in a blank field of a Hello packet at a timing at which the relay device information is periodically transmitted, to a node belonging to the relay device network of the other relay device. Transmitting The self-supporting distributed network system according to any one of claims 1 to 5 . Said control server, said recovery relay device information, for the particular node belonging to the relay device network of other of the relay devices, to any one of claims 1 to 5, transmitted using a unicast communication The self-supporting distributed network system described. Said control server, wherein the recovery relay device information to the node that belong to a particular repeater network of other of the relay devices, to any one of claims 1 to 5, transmitted using the multicast communication Independent distributed network system. The other relay device belongs to the relay device network of the other relay device at a timing different from the timing at which the relay device information is periodically transmitted using the overall distribution communication. The autonomous distributed network system according to any one of claims 1 to 5, wherein the network is transmitted to a node. The self-sustained distributed network system according to any one of claims 6 to 9 , wherein the restoration relay device information includes information indicating that one of the relay devices has been replaced.

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