JP6503982B2 - Wireless communication device, method, program and system - Google Patents

Description

  The present invention relates to a wireless communication device, method, program, and system, and can be applied to, for example, a wireless communication device, method, program, and system that performs communication between wireless communication devices of a wireless multi-hop network.

  In recent years, IEEE 802.15.4 has been adopted as a standardization standard of MAC (Media Access Control) layer of a wireless communication device (hereinafter referred to as a "node") configuring a short distance wireless network (for example, smart network, sensor network, etc.). -A protocol stack of 2012 system (hereinafter referred to as "IEEE 802.15.4") is adopted.

  IEEE 802.15.4 defines two types of communication: secure communication and non-secure communication. For example, secure communication is implemented by sharing an encryption key between nodes. Also, according to IEEE 802.15.4, when a node is set to perform secure communication, that node discards a non-secure communication frame (that is, an unencrypted frame) without receiving it. Do the processing.

  In the NW layer protocol of the general sensor network (for example, ZigBee (registered trademark) IP etc.), node information around itself is stored in a table (hereinafter referred to as “peripheral node information table”). The “node information” is information including its own node address and an encryption key for secure communication.

  Also, in the NW layer protocol of a general sensor network, peripheral information is exchanged with each other at regular intervals. “Peripheral information” is information including a transmission source node address for transmitting peripheral information and an address list of peripheral nodes of the transmission source node address.

  For example, nodes performing wireless communication in accordance with ZigBee IP use MLE (Mesh Link Establishment) or the like to perform information exchange between nodes and alive management of peripheral nodes. For example, when information exchange with another node is interrupted, a certain node determines that there is no other node which is interrupted, and deletes node information of the corresponding node from the peripheral node information table. Also, if a certain child node finds that its own address does not exist in the peripheral node address list in the peripheral information transmitted by its own parent node, it determines that the parent node does not recognize its existence. Will execute a rejoining routine to the network.

IEEE 802.15.4-2012

  When using a MAC protocol stack compliant with IEEE 802.15.4, the following asymmetric link problems may occur.

  "Asymmetric link" indicates a link in which one-way communication is established but communication in the opposite direction is not established when the communication environment between nodes is poor. For example, node A (parent node) and node A link between the nodes A and B (child node) is a link that establishes communication from the node A to the node B but does not establish communication from the node B to the node A. When such an asymmetric link occurs, the node A does not receive the peripheral information from the node B. Therefore, the node A judges that the node B has left the network and uses the node information of the node B from its peripheral node information table. delete.

  After this, since the encryption key included in the node information of the node B is also discarded, the node A can execute only non-secure communication even if there is a communication request to the node B. However, since the node B is waiting for reception in secure communication, the frame from the node A is discarded.

  The state of such an asymmetric link continues until node B receives peripheral information of node A, determines that node B is not known to exist at node A, and executes a rejoin routine to the network. become.

  That is, by executing the rejoining routine by the node B, both nodes can not perform secure communication until the node A registers the peripheral information (including the encryption key) of the node B in the peripheral node information table. Also, executing the network participation routine will increase traffic in the network.

  Therefore, there is a need for a wireless communication device, method, program, and system that can efficiently receive peripheral information even when the communication environment between nodes is poor.

  According to a first aspect of the present invention, in a wireless communication apparatus which exchanges peripheral information including at least an identifier of a peripheral wireless communication apparatus with a peripheral wireless communication apparatus, (1) the peripheral information is transmitted periodically (2) peripheral information receiving means for receiving the peripheral information during a predetermined communication period, (3) an identifier for identifying at least a peripheral wireless communication device, and secure communication with the peripheral wireless communication device Peripheral information storage means for storing node information including an encryption key for performing; (4) peripheral information detection means for detecting whether the peripheral information could be received during the communication period; (5) the peripheral information detection In the case of non-detection by means, it is characterized by comprising communication period extension means for extending the communication period.

  According to a second aspect of the present invention, there is provided a wireless communication method in a wireless communication apparatus for exchanging peripheral information including at least an identifier of a peripheral wireless communication apparatus with a peripheral wireless communication apparatus. The information receiving means, the peripheral information storage means, the peripheral information detecting means, and the communication period extending means, (1) the peripheral information transmitting means periodically transmits the peripheral information, and (2) the peripheral The information receiving means receives the peripheral information during a predetermined communication period, and (3) the peripheral information storage means performs secure communication with at least an identifier for identifying a wireless communication device in the vicinity and the wireless communication device in the vicinity. And (4) the peripheral information detection unit detects whether the peripheral information could be received during the communication period, and (5) the communication period extension unit is configured to Peripheral information check If it was non-detection by means, characterized in that extending the communication period.

  According to a third aspect of the present invention, there is provided a wireless communication program installed in a wireless communication device for exchanging peripheral information including at least an identifier of the peripheral wireless communication device with the peripheral wireless communication device. Peripheral information transmitting means for transmitting the peripheral information, (2) peripheral information receiving means for receiving the peripheral information during a predetermined communication period, (3) an identifier for identifying at least a peripheral wireless communication device, Peripheral information storage means for storing node information including a wireless communication apparatus of the above and an encryption key for performing secure communication; (4) peripheral information detection means for detecting whether the peripheral information could be received during the communication period; (5) When not detected by the peripheral information detecting means, the peripheral information detecting means functions as a communication period extending means for extending the communication period.

  A fourth aspect of the present invention is a wireless communication system including: a plurality of wireless communication devices; and a management device that manages a network configured by the plurality of wireless communication devices, wherein the wireless communication device includes (1-1) periodical Peripheral information transmitting means for transmitting peripheral information including at least the identifier of the wireless communication device in the vicinity, (1-2) peripheral information receiving means for receiving the peripheral information during a predetermined communication period, (1-3 Peripheral information storage means for storing node information including at least an identifier for identifying a peripheral wireless communication device and an encryption key for performing secure communication with the peripheral wireless communication device; (1-4) During the communication period Peripheral information detecting means for detecting whether the peripheral information has been received, and (1-5) deleting the node information related to the wireless communication device that was not detected by the peripheral information detecting means. Deletion information notifying means for notifying deletion information indicating that it is scheduled to be performed, and (1-6) node information relating to a wireless communication apparatus which has not been detected if the peripheral information (2-1) erasure information receiving means for receiving the erasure information; and (2-2) the erasure information received by the erasure information receiving means. The information processing apparatus is characterized by further comprising: network participation promoting means for executing predetermined processing to urge the wireless communication device to be deleted to join the network again when the information is received.

  According to the present invention, peripheral information can be efficiently received even when the communication environment between nodes is poor.

It is a block diagram showing composition of a radio communication apparatus concerning an embodiment. 1 is a block diagram showing an overall configuration of a wireless communication system according to an embodiment. It is a flowchart which shows operation | movement of the radio | wireless communication apparatus which concerns on embodiment.

(A) Main Embodiment Hereinafter, embodiments of a wireless communication apparatus, method, program and system according to the present invention will be described in detail with reference to the drawings.

(A-1) Configuration of Embodiment FIG. 2 is a block diagram showing the overall configuration of a wireless communication system 1 according to this embodiment.

  In FIG. 2, in order to facilitate the description, the case where the wireless communication system 1 includes two wireless communication devices 10 (10-1 and 10-2) is illustrated. Of course, the number of wireless communication devices 10 is not particularly limited.

  The communication method of the wireless communication apparatus 100 (10-1 to 10-2) is not limited, and, for example, various wireless LAN interfaces can be applied. For example, in this embodiment, it is assumed that the wireless communication devices 10 (10-1, 10-2) adopt the wireless communication system of IEEE 802.15.4.

  FIG. 1 is a block diagram showing the internal configuration of the wireless communication apparatus according to this embodiment. The wireless communication apparatus according to the embodiment may be configured as hardware such as a dedicated IC chip on which each component shown in FIG. 1 is mounted, or may be software-centered around a CPU and a program executed by the CPU. It can be configured as shown in FIG. 1 functionally.

  In FIG. 1, the wireless communication apparatus 10 includes a peripheral information transmission unit 101, a peripheral information reception unit 102, a peripheral node information table 103, a communication period extension unit 104, a wireless transmission unit 105, and a wireless reception unit 106.

  The peripheral information transmission unit 101 periodically supplies node information (for example, node address) stored in a peripheral node information table 103 described later to the wireless transmission unit 105 as peripheral information.

  The wireless transmission unit 105 converts the peripheral information provided from the peripheral information transmission unit 101 into a wireless signal (radio wave) and transmits it to the peripheral node.

  The wireless reception unit 106 extracts peripheral information from radio waves received from other peripheral nodes and gives the peripheral information reception unit 102.

  The peripheral information reception unit 102 extracts node information from the peripheral information supplied from the wireless reception unit 106 and instructs the peripheral node information table 103 to store the node information. When the peripheral information reception unit 102 can not receive peripheral information from a certain node, the peripheral information reception unit 102 instructs the peripheral node information table 103 to delete the node information that can not be received.

  The peripheral node information table 103 is a table for storing information on peripheral nodes. The peripheral node information table 103 is for updating or providing internal node information in response to requests from the peripheral information transmission unit 101, the peripheral information reception unit 102, and the communication period extension unit 104. The node information here is information held for each peripheral node, and is information such as an identifier (for example, a node address) uniquely identifying the node on the network, an encryption key for performing secure communication, etc. . Here, the peripheral node information table 103 acquires in advance an encryption key for each node by a predetermined means. For example, the peripheral node information table 103 acquires an encryption key via an external storage medium (for example, an SD memory card), or generates an encryption key when communication with another peripheral node is established, or encryption Obtain the key from an external server (not shown) that manages the key.

  The communication period extension unit 104 monitors a change in the peripheral node information table 103, and when detecting a change, extends the communication period between nodes. Hereinafter, the configuration of the communication period extension unit 104 will be described in detail.

  The communication period extension unit 104 has a timer 1041 and a control unit 1042.

  The timer 1041 counts time inside the wireless communication device 100.

  The control unit 1042 causes the peripheral information reception unit 102 to delete certain node information including the encryption key in the peripheral node information table 103 when the monitoring value (measurement time) of the timer 1041 exceeds a predetermined threshold. When it detects by the notice (signal) from, it postpones deleting predetermined | prescribed period information for a predetermined period. When the communication period extension unit 104 receives the peripheral information from the corresponding node from the peripheral information reception unit 102 during the postponement period, the communication period extension unit 104 cancels the deletion of the node information, and when the reception can not be performed, the communication period extension unit 104 actually An instruction to delete the corresponding node from the node information table 103 is issued.

  The communication period extension unit 104 can use various values for the monitoring value of the timer 1041 described above, for example, a participation period after the node joins the network, and a target node including an encryption key A period of time elapsed since the information was registered in the peripheral node information table 103, or a power supply period after the node is powered on may be used. Also, the threshold that the communication period extension unit 104 compares with the monitoring value of the timer 1041 may be a variable value.

(A-2) Operation of Embodiment Next, the operation of the wireless communication system 1 of this embodiment having the configuration as described above will be described with reference to the drawings. In the following description, a parent node of the wireless communication system 1 is referred to as a wireless communication device 10-1 (hereinafter also referred to as "node 10-1"), and a child node is referred to as a wireless communication device 10-2 (hereinafter referred to as "node Also referred to as “10-2”. Further, it is assumed that node information related to the node 10-2 is stored in the peripheral node information table 103 of the node 10-1.

  FIG. 3 is a flowchart showing the operation of the wireless communication apparatus according to the embodiment.

  The peripheral information transmission unit 101 creates peripheral information including node information related to the node 10-2 stored in the peripheral node information table, and periodically transmits the peripheral information to the node 10-2 via the wireless transmission unit 105. To (S101).

  The peripheral information receiving unit 102 determines whether peripheral information from the node 10-2 has been received for a certain period (S102). When the peripheral information reception unit 102 can receive the peripheral information from the node 10-2, the peripheral information reception unit 102 ends without performing the subsequent processing and performs the following processing when the peripheral information reception unit 102 can not receive the peripheral information.

  When the peripheral information reception unit 102 can not receive peripheral information from the node 10-2 for a certain period, the peripheral information reception unit 102 uses node information related to the node 10-2 from the peripheral node information table 103 in secure communication with the node 10-2. The communication period extension unit 104 is notified that it is scheduled to be deleted together with the encryption key to be deleted (node information deletion notice) (S103).

  When the communication period extension unit 104 (control unit 1042) detects a node information deletion notice, the monitoring value of the timer 1041 inside itself (for example, node information including an encryption key related to the node 10-2 is stored in the peripheral node information table 103). It is determined whether or not the elapsed time since storage exceeds a threshold (S104). The communication period extension unit 104 performs the process of step S108 described later when the monitoring value of the timer 1041 does not exceed the threshold, and performs the following process when the threshold is exceeded.

  The communication period extension unit 104 extends the deletion of the node information including the encryption key related to the node 10-2 from the peripheral node information table 103, when the monitoring value of the timer 1041 exceeds the threshold (S105). ).

  The communication period extension unit 104 determines whether or not the peripheral information reception unit 102 can receive the peripheral information from the node 10-2 during the period extended by the process of step S105 (S106). The communication period extension unit 104 performs the process of step S108 described later when the peripheral information from the node 10-2 can not be received, and performs the following process when the peripheral information can be received.

  When the peripheral information receiving unit 102 receives the peripheral information of the node 10-2 during the period extended by the process of step S105, the communication period extending unit 104 stores the node information including the encryption key related to the node 10-2. Deletion from the peripheral node information table 103 is canceled (S107).

  On the other hand, when the peripheral information reception unit 102 can not receive the peripheral information of the node 10-2 during the period extended by the process of step S105, the communication period extension unit 104 does not receive the peripheral node information table 103 as originally planned. The node information including the encryption key related to the node 10-2 is deleted (S108).

(A-3) Effects of the Embodiment According to this embodiment, the following effects can be achieved.

  When the monitoring value of timer 1041 exceeds the threshold, communication period extension unit 104 extends the period in which peripheral information from peripheral nodes can be received (in other words, timing of erasing node information from peripheral node information table 103) By deferring, the probability that peripheral information from peripheral nodes can be received is increased. For example, even if communication between the peripheral nodes can not be temporarily exchanged due to deterioration of the communication environment in the network, etc., the radio communication apparatus 10 of this embodiment has a probability that peripheral information can be received conventionally. It is higher than.

  The wireless communication device 10 can receive peripheral information from the peripheral node during the extension period. Thus, the wireless communication device 10 can avoid the inability to perform secure communication with the peripheral node, which is caused by the deletion of the target node information including the encryption key from the peripheral node information table 103. In addition, it is possible to suppress the wasteful occurrence of the network participation routine of the target node. In other words, the traffic in the network is reduced.

(B) Other Embodiments Also in the description of this embodiment, various modified embodiments are mentioned, but further, modified embodiments as exemplified below can also be mentioned.

  (B-1) In this embodiment, the wireless communication apparatus 10 uses the wireless communication system of IEEE 802.15.4 as an example of the wireless communication system, but the present invention is not limited to this example. The present invention can be applied to a communication apparatus adopting a wireless communication system that is a development, derivation and similar to the wireless communication system.

  (B-2) In this embodiment, when peripheral information can not be received from the node 10-2, the communication period extension unit 104 uses the node information related to the node 10-2 from the peripheral node information table 103 in secure communication. It is extended to actually delete the node information at the timing of deleting with the encryption key (determining that the node 10-2 has left the network). On the other hand, without extending the communication period extension unit 104, the communication period extension unit 104 may actually delete the node information and notify the management device (for example, gateway) that manages the network to that effect. Since the management device urges the erased node 10-2 to rejoin the network early, the period in which the nodes 10-1 and 10-2 can not communicate is indirectly shortened. .

  DESCRIPTION OF SYMBOLS 1 wireless communication system, 10 (10-1, 10-2) wireless communication device 100 wireless communication device 101 peripheral information transmitting unit 102 peripheral information receiving unit 103 peripheral node information table 104 Communication period extension unit 105: wireless transmission unit 106: wireless reception unit 1041: timer 1042: control unit.

Claims (7)

In a wireless communication apparatus, which exchanges peripheral information with at least a peripheral wireless communication apparatus with peripheral information including at least an identifier of the peripheral wireless communication apparatus,
Peripheral information transmission means for transmitting the peripheral information periodically;
Peripheral information receiving means for receiving the peripheral information during a predetermined communication period;
Peripheral information storage means for storing node information including at least an identifier for identifying a wireless communication device in the vicinity and an encryption key for performing secure communication with the wireless communication device in the vicinity;
Peripheral information detection means for detecting whether the peripheral information has been received during the communication period;
A wireless communication device, comprising: a communication period extension unit that extends the communication period when the peripheral information detection unit does not detect the communication information. The information processing apparatus further comprises peripheral information erasing means for deleting node information relating to a wireless communication device that has not been detected from the peripheral information storage means when the peripheral information detection means does not detect the information.
The peripheral information eraser temporarily suspends the process of erasing the node information when the peripheral information detector does not detect the node information.
The communication period extension unit actually cancels the processing for deleting the node information when the peripheral information detection unit detects the peripheral information related to the wireless communication device scheduled to be deleted during the extended communication period. The wireless communication device according to claim 1.   The wireless communication apparatus according to claim 1 or 2, further comprising: determination means for comparing a predetermined measurement time relating to the wireless communication device with a threshold and determining whether to perform the extension process by the communication period extension means based on the comparison result. The wireless communication device according to 2. The wireless communication device according to claim 3, wherein the measurement time is an elapsed time after the wireless communication device joins a nearby network. In a wireless communication method in a wireless communication apparatus, which exchanges peripheral information including at least an identifier of a wireless communication apparatus in the vicinity with a wireless communication apparatus in the vicinity,
Peripheral information transmitting means, peripheral information receiving means, peripheral information storing means, peripheral information detecting means, communication period extending means
The peripheral information transmission means periodically transmits the peripheral information;
The peripheral information receiving means receives the peripheral information during a predetermined communication period,
The peripheral information storage means stores node information including at least an identifier for identifying a peripheral wireless communication device, and an encryption key for performing secure communication with the peripheral wireless communication device.
The peripheral information detection means detects whether the peripheral information has been received during the communication period,
The wireless communication method, wherein the communication period extension unit extends the communication period when the peripheral information detection unit does not detect the communication period. In a wireless communication program mounted on a wireless communication apparatus, which exchanges peripheral information including at least an identifier of the wireless communication apparatus with the peripheral wireless communication apparatus.
Peripheral information transmission means for transmitting the peripheral information periodically;
Peripheral information receiving means for receiving the peripheral information during a predetermined communication period;
Peripheral information storage means for storing node information including at least an identifier for identifying a wireless communication device in the vicinity and an encryption key for performing secure communication with the wireless communication device in the vicinity;
Peripheral information detection means for detecting whether the peripheral information has been received during the communication period;
A wireless communication program characterized by causing the communication information to be extended as communication period extending means for extending the communication period when the peripheral information detecting means is not detecting. In a wireless communication system including a plurality of wireless communication devices and a management device that manages a network configured of the plurality of wireless communication devices,
The wireless communication device is
Peripheral information transmission means for periodically transmitting peripheral information including at least an identifier of a peripheral wireless communication device;
Peripheral information receiving means for receiving the peripheral information during a predetermined communication period;
Peripheral information storage means for storing node information including at least an identifier for identifying a wireless communication device in the vicinity and an encryption key for performing secure communication with the wireless communication device in the vicinity;
Peripheral information detection means for detecting whether the peripheral information has been received during the communication period;
If the peripheral information detection unit does not detect the wireless communication device, the peripheral information detection unit notifies the deletion information notifying that deletion information indicating that the node information related to the wireless communication device that is not detected is scheduled to be deleted. And peripheral information erasing means for erasing node information relating to the wireless communication device that has not been detected from the peripheral information storage means when not detected.
The management device
Erasure information receiving means for receiving the erasure information;
Network participation promoting means for executing predetermined processing to urge the wireless communication device to be deleted to join the network again when the deletion information is received by the deletion information receiving means. Wireless communication system.

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