JP4913208B2 - Address resolution method - Google Patents

Description

  The present invention relates to an address resolution method in multi-hop communication in which a large number of terminals (nodes) are interconnected without intervention of an access point.

  Currently, various routing protocols (route control methods) have been proposed for realizing an ad hoc network. Here, the ad hoc network is a network configured only by terminals (nodes) that can be connected wirelessly without requiring an access point such as a wireless LAN.

  For example, in DSR (Dynamic Source Routing) and IODV (Ad Hoc On Demand Distance Vector Routing) in IETF, each node establishes a path from the source node to the destination node at the start of data transfer as an On-Demand type. Has been proposed.

  Further, in OLSR (Optimized Link State Routing) and the like, a protocol is proposed as a proactive type in which messages are periodically exchanged with adjacent nodes to update route information held by itself.

  In addition to ad hoc communication, a node generally holds an identifier (address) for distinguishing its own node from other nodes, and uses an identifier indicating its own node or an identifier indicating another node. Communication route information is created and stored, and used to transfer messages.

  IEEE 802.15.4 can perform wireless communication using either a real address (64-bit address) or a logical address (16-bit address) depending on the setting. In ZigBee (registered trademark of ZigBee Alliance) using IEEE802.15.4 as a wireless standard, a 16-bit address called a short address is used, and a short address (NWK address, 16-bit address, logical address) and a real address (IEEE address) , 64-bit address), device discovery is used (see, for example, Non-Patent Document 1).

  In device discovery, in order to obtain the logical address (NWK address, short address, 16-bit address) of the Target node, a message with the actual address (IEEE address, 64-bit address) of the desired node is flooded and added. A method is used in which a node holding a real address is queried. Conversely, when a real address is desired, a method is used in which a short address is set and the address is inquired using a unicast message.

  Then, after the logical address of the Target node is resolved, the route search process is performed using the logical address.

ZigBee Architecture Overview, P15

However, the prior art has the following problems.
Here, in multi-hop communication on an ad hoc network configured by nodes having real addresses (for example, 64-bit length addresses), a system that performs communication using a logical address (for example, 16-bit length addresses) in a wireless link. think of. Further, since the logical address is calculated from the network configuration, random number, and the like, it is difficult to make it known in advance. In other words, this is a system that requires a mechanism for associating (address resolution) a real address with a logical address in order to uniquely designate each node after activation of the node constituting the ad hoc network.

  For example, in ZigBee that employs IEEE 802.15.4 for wireless communication, nodes on the ad hoc network have a role of parent and child, and logical addresses are assigned according to the parent-child relationship. For this reason, the assigned logical address is an address depending on the state of each node constituting the ad hoc network. If device discovery used in ZigBee is used, it is possible to resolve an address, but in order to resolve a logical address from a real address, flooding is performed.

  Furthermore, when the route to the destination node is not held, the route search processing by Flooding is performed after the address resolution processing is performed. That is, in the conventional wireless communication using ZigBee, two broadcast message transmission processes, that is, an address resolution process and a route search process, are required, and there is a problem that traffic increases.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide an address resolution method for multi-hop communication that suppresses traffic and efficiently resolves addresses.

In an address resolution method according to the present invention, in an ad hoc network having a plurality of nodes where real addresses and logical addresses exist, one destination node from one source node passes through one or more other relay nodes. When sending a message, the transmission is started from a state where the logical address of the own node and the real addresses of all the nodes are known and the logical addresses of other nodes other than the own node are unknown. An address resolution method for a source node to obtain a logical address of a destination node, wherein the source node has a first address information including its own logical address and real address, and the real address of the destination node. it broadcasts a request message on an ad hoc network, a source node and a destination node The relay node that is located between and receives the route search request message includes a logical address and a real address of the transmission source node included in the first address information, and a reverse that includes the real address of the node that has transmitted the route search request message. In addition to storing the Path route information, the route search request message is broadcast on the ad hoc network . And the relay node that has received the route search response message is unicasted to the relay node that has transmitted the route search request message, and the relay node that has received the route search response message stores Reverse Path path According to the information, the route search response message is unicast so as to reverse the transmission route of the route search request message, and the transmission source node returns the route search request message via the transmission route of one or more relay nodes. By receiving the received route search response message, a message transmission route is established, and the logical address of the destination node is obtained from the second address information included in the route search response message.

  According to the present invention, when a message transmission route is established by route search processing, address resolution between a real address and a logical address of a destination node is attempted, so that traffic can be suppressed and an address can be efficiently resolved. An address resolution method for hop communication can be obtained.

It is the figure which showed the ad hoc network structure with which the address resolution method in Embodiment 1 of this invention is applied. It is a figure which shows the real address and logical address of each node in the ad hoc network structure of FIG. 1 to which the address resolution method in Embodiment 1 of this invention is applied. It is a figure which shows the internal structure of the node to which the address resolution method in Embodiment 1 of this invention is applied. It is a figure for demonstrating the definition of the term regarding the address resolution method in Embodiment 1 of this invention. It is a sequence diagram for demonstrating an example of the message transmission process regarding the route search process in Embodiment 1 of this invention. It is a figure which shows the list of the address information relevant to the route search request message and route search response message which were shown in FIG. 5 in Embodiment 1 of this invention. 5 is a flowchart relating to processing in an Originating node in transmission of a route search request message in Embodiment 1 of the present invention. 7 is a flowchart relating to processing in a node that is not an Originating node of a route search request message in transmission of a route search request message in Embodiment 1 of the present invention. 6 is a flowchart relating to processing in an Originating node in replying a route search response message in Embodiment 1 of the present invention. 7 is a flowchart regarding processing in a node that is not an Originating node of a route search response message in replying a route search response message in Embodiment 1 of the present invention.

Hereinafter, preferred embodiments of the address resolution method of the present invention will be described with reference to the drawings.
The address resolution method of the present invention performs a route search process using a real address, and by processing a broadcast message once in this route search process, the logic of a source node and a destination node that are nodes at both ends of communication is performed. The technical feature is to provide an efficient wireless communication with address reduction and traffic control.

Embodiment 1 FIG.
FIG. 1 is a diagram showing an ad hoc network configuration to which the address resolution method according to Embodiment 1 of the present invention is applied. The ad hoc network in FIG. 1 is composed of seven nodes 1 to 7, each having a wireless function. When the nodes 1 to 7 are within the communicable range by the mounted wireless communication function, the nodes 1 to 7 can perform packet transmission and packet reception.

  In FIG. 1, two nodes connected by a dotted line are in a state where they are within a wireless communicable range. For example, the node 1 can communicate with each of the node 2 and the node 3, and the node 7 can communicate with each of the node 4, the node 5, and the node 6.

  Each node 1-7 which comprises FIG. 1 can communicate using either a real address or a logical address as a radio | wireless standard. As an example, a system adopting IEEE 802.15.4 can be considered. In addition, in ZigBee using IEEE802.15.4, the logical address is different for each activation, and therefore the node cannot be uniquely specified using the logical address in advance.

  Therefore, assuming such a situation, the application in the first embodiment uses a real address to uniquely identify the node, and further, in the route search process, sets the source node and the destination node. The real address is used for identification, and route search processing is performed to finally resolve the addresses of the logical addresses of both nodes.

  FIG. 2 is a diagram showing the real address and logical address of each node in the ad hoc network configuration of FIG. 1 to which the address resolution method according to Embodiment 1 of the present invention is applied. In the ad hoc network configuration of FIG. 1, each of the nodes 1 to 7 has its own logical address known at the time of activation, but the logical addresses of other nodes are unknown.

  Specifically, for example, node 1 has its own logical address known, but the logical addresses of other nodes 2 to 7 are unknown, and node 7 has its own logical address known, The logical addresses of the other nodes 1 to 6 are unknown.

  Further, each of the nodes 1 to 7 is assumed to have known real addresses of all nodes existing on the ad hoc network including itself. Specifically, for example, the node 1 has known real addresses of all the nodes 1 to 7 including the other nodes 2 to 7, and the node 7 includes the other nodes 1 to 6 as well. The real addresses of all the nodes 1 to 7 are known.

  The radio | wireless which each node 1-7 uses for communication can communicate using a real address or a logical address like IEEE802.15.4, for example. However, in the application of the first embodiment, a real address is used to uniquely identify a node.

  Each node 1 to 7 receives a 1-hop broadcast message (for example, a beacon or a Hello message) periodically transmitted after adding a real address and a logical address from adjacent nodes. Thus, address resolution is performed for the logical address and real address of the adjacent nodes.

  Specifically, for example, the node 1 has the node 2 and the node 3 as nodes within the communicable range, and the real address and the logical address of the node 2 and the node 3 having such an adjacent relationship are as follows: This can be solved by communication of a one-hop broadcast message. Further, for example, the node 7 has the node 4, the node 5 and the node 6 as nodes within the communicable range, and the real address and logical address of the node 4, the node 5 and the node 6 which are in such an adjacent relationship. Can be solved by communication of a one-hop broadcast message.

  FIG. 3 is a diagram illustrating an internal configuration of a node to which the address resolution method according to the first embodiment of the present invention is applied, and is a structure common to the nodes 1 to 7. Each of the nodes 1 to 7 includes a wireless unit 11, a route control unit 12, and a memory 13. In the following description, the numbers 1 to 7 described in parentheses correspond to the nodes 1 to 7, for example, the wireless unit 11 (1) means the wireless unit 11 included in the node 1. It shall be.

  The wireless unit 11 has a function that enables wireless communication with other nodes. The route control unit 12 has a function of designating a transfer destination of a message received by the wireless unit 11 or a message transmitted from itself. Furthermore, the memory 13 is a storage unit for recording temporary information during various processing and processing results.

  Next, definitions of terms used in the present invention will be described. FIG. 4 is a diagram for explaining definitions of terms relating to the address resolution method according to the first embodiment of the present invention. The ad hoc network shown in FIG. 4 is composed of three nodes 1 to 3 for the sake of simplicity. Further, between the node 1 and the node 2 and between the node 2 and the node 3 are in a wireless communicable area.

  At this time, it is assumed that a message is transmitted from the node 1 to the node 3 via the node 2. In transmitting a message, the node 1 is called an Originating node and corresponds to a transmission source node. Node 3 is called a Target node and corresponds to a destination node. Further, the node 2 existing on the route between the message destination node and the message transmission source node is called an Intermediate node and corresponds to a relay node.

  In addition, the address of the Originating node is called a source address, and the address of the Target node is called a destination address. Furthermore, in the route created as a result of route search processing from the Originating node to the Target node, the route from the Originating node to the Target node is called Forward Path, and conversely, the route is directed from the Target node to the Originating node. The route is referred to as Reverse Path.

  When a message is transmitted from the Originating node to the Target node (that is, when a message is transmitted from the node 1 in FIG. 4 to the node 3), via the Intermediate node (that is, the node 2 in FIG. 4). Transferred. At this time, the transmission from the Originating node to the Intermediate node (Node 1 to Node 2 in FIG. 4) is called 1-hop transmission. In this case, the Originating node (Node 1 in FIG. 4) is the transmission source of the 1-hop transmission, the Intermediate node ( Node 2) in FIG. 4 is referred to as a one-hop transmission destination.

  Transmission from the Intermediate node to the Target node (node 2 to node 3 in FIG. 4) is also called 1-hop transmission. In this case, the Intermediate node (node 2 in FIG. 4) is the transmission source of 1-hop transmission, Target The node (node 3 in FIG. 4) is referred to as a one-hop transmission destination.

  Next, in the ad hoc network having the configuration shown in FIG. 1 described above, a series of flow of route search processing when the node 1 transmits a message to the node 7 will be described with reference to FIGS. To do.

  FIG. 5 is a sequence diagram for explaining an example of message transmission processing related to route search processing according to Embodiment 1 of the present invention. More specifically, in the ad hoc network configuration shown in FIG. 1, when a message is to be transmitted with the node 1 as the transmission source node and the node 7 as the destination node, as a previous step, a flooding (broadcast) from the node 1 is performed. In the route search request message, the route search request message finally transmitted to the node 7 via the nodes 2 and 5 and the node 7 → node 5 → node 2 → node in response thereto 1 shows a route search response message returned (unicast) via 1.

  FIG. 6 is a diagram showing a list of address information 21 to 28 related to the route search request message and the route search response message shown in FIG. 5 according to the first embodiment of the present invention.

  Specifically, the address information 21 (corresponding to the first address information) is address information generated by the node 1 that is the transmission source of the route search request message and added to the route search request message to be transmitted. Further, the address information 22 to 24 is stored in the path information table stored in the memory 13 (2) of the node 2, the memory 13 (5) of the node 5, and the memory 13 (7) of the node 7, respectively. Path address information.

  The address information 25 (corresponding to the second address information) is address information generated by the node 7 that is the transmission source of the route search response message for the route search request message and added to the route search response message to be transmitted. . The address information 26 and 27 indicate address information set in the path information table stored in the memory 13 (5) of the node 5 corresponding to the Intermediate node and the memory 13 (2) of the node 2, respectively. The upper row is the reverse path address information already set as the address information 23 and 22, and the lower row is the address information set as the forward path corresponding to the route search response message.

  Further, the address information 28 is Reverse Path address information set in the path information table stored in the memory 13 (1) of the node 1. The details of the address information 21 to 28 shown in FIG. 6 will be described later in accordance with the description of the flowcharts shown in FIGS.

  First, the processing of the route search request message will be described with reference to FIGS. FIG. 7 is a flowchart relating to processing at the Originating node in transmission of a route search request message according to Embodiment 1 of the present invention. Specifically, corresponding to FIG. 5 and FIG. 6, the processing performed in the node 1 that is the Originating node of the route search request message is summarized.

  When there is a transmission request for a message to be transmitted from the node 1 to the node 7 (step S71), the path control unit 12 (1) of the node 1 stores the path information toward the node 7 in the memory 13 (1). It is confirmed whether or not it is stored in the path information table (step S72). More specifically, it is confirmed whether or not the Forward Path with the node 7 as the destination node is set in the route information table.

  Next, when the route information to the node 7 already exists in the route information table in the memory 13 (1), the route control unit 12 (1) sends a message for which a transmission request has been made according to the route information. Is transmitted (step S73).

  On the other hand, when the route information to the node 7 does not exist in the route information table in the memory 13 (1), the route control unit 12 (1) sets the Waiting Queue secured in the area in the memory 13 (1). Then, the message requested for transmission is queued (step S74), and a route search request message is created (step S75).

  As shown in FIG. 6, the path control unit 12 (1) has address information including the real address 271 of the node 7 that is the target node, the real address 211 and the logical address 212 of the node 1 that is the Originating node. 21 (see FIG. 6) is generated and added to the route search request message.

  Then, the wireless unit 11 (1) floods (that is, broadcasts) the route search request message generated by the route control unit 12 (1) and to which the address information 21 is added on the ad hoc network (step S76).

  Next, FIG. 8 is a flowchart relating to the processing in the node other than the Originating node of the route search request message in the transmission of the route search request message in Embodiment 1 of the present invention. Specifically, in correspondence with FIG. 5 and FIG. 6, the processes performed by the nodes 2 and 5 that are Intermediate nodes and the node 7 that is the Target node of the route search request message are summarized.

  The operation corresponding to the flowchart of FIG. 8 will be described in the order of node 2, node 5, and node 7 in accordance with the order of receiving the route search request message in FIG.

  First, the operation of the node 2 will be described. The wireless unit 11 (2) of the node 2 receives the route search request message from the node 1. Then, the route control unit 12 (2) of the node 2 receives the real address 211 of the node 1 that is the transmission source of the one-hop transmission of the received route search request message, and the realization of the Originating node added to the route search request message. Using the address 211 and the logical address 212, a Reverse Path (corresponding to the address information 22 shown in FIG. 6) is set in the route information table in the memory 13 (2) (step S81). This Reverse Path information is used later when a route search response message for the route search request message is returned from the node 2 to the node 1.

  Then, the path control unit 12 (2) of the node 2 checks whether or not the real address 271 of the Target node added to the path search request message is the real address 221 indicating itself (step S82).

  In this case, since the node 2 is not a Target node and step S82 is not true, the wireless unit 11 (2) of the node 2 does not change the content of the route search request message received from the node 1 and changes the route. The search request message is flooded as it is (step S83).

  Next, the operation of the node 5 will be described. In the node 5 that has received the route search request message that has been flooded from the node 2, the real address 221 of the node 2 that is the transmission source of the one-hop transmission of the received route search request message and the Originating that is added to the route search request message A reverse path (corresponding to the address information 23 shown in FIG. 6) is set in the path information table in the memory 13 (5) using the real address 211 and the logical address 212 of the node (step S81). This Reverse Path information is used later when a route search response message for the route search request message is returned from the node 5 to the node 2.

  Then, the route control unit 12 (5) of the node 5 checks whether or not the real address 271 of the Target node added to the route search request message is the real address 251 indicating itself (step S82).

  In this case, since the node 5 is not a Target node and Step S82 is not true, the wireless unit 11 (5) of the node 5 does not change the content of the route search request message received from the node 2, and The search request message is flooded as it is (step S83).

  Next, the operation of the node 7 will be described. In the node 7 that has received the route search request message that has been flooded from the node 5, the real address 251 of the node 5 that is the transmission source of the one-hop transmission of the received route search request message and the Originating that is added to the route search request message Using the real address 211 and the logical address 212 of the node, a Reverse Path (corresponding to the address information 24 shown in FIG. 6) is set in the path information table in the memory 13 (7) (step S81). This Reverse Path information is used later when a route search response message for the route search request message is returned from the node 7 to the node 5.

  Then, the route control unit 12 (7) of the node 7 checks whether or not the real address 271 of the Target node added to the route search request message is the real address 271 indicating itself (step S82).

  In this case, since the node 7 is a Target node and Step S82 is true, the route control unit 12 (7) of the node 7 searches for the real address 211 of the Originating node of the route search request message. A response message transmission process is performed (step S84).

  In transmission of a route search request message by Flooding, each node manages the sequence number of the Originating node. When a message having the same sequence number is received from the same Originating node, the received message is discarded.

  Next, processing of a route search response message in response to a route search request message will be described with reference to FIGS. FIG. 9 is a flowchart relating to processing at the Originating node in replying a route search response message according to Embodiment 1 of the present invention. Specifically, corresponding to FIG. 5 and FIG. 6, the processes performed in the node 7 that is the Originating node of the route search response message are summarized.

  Address information 25 shown in FIG. 6 is added to the route search response message returned from the node 7 (step S91). Specifically, the real address 211 of the Originating node of the route search request message is set as the real address of the Target node in the route search response message, and the node 7 itself that is the transmission source of the route search response message is set as the address of the Originating node Real address 271 and logical address 272 are set.

  The route search response message is returned according to the Reverse Path set in the route information table in the memory 33 of each node. That is, as a route returned from the node 7 to the node 1, the wireless unit 11 (7) of the node 7 uses the real address according to the address information 24 of the Reverse Path set in the route information table in the memory 13 (7). A route search response message is returned (that is, unicast) to the node 5 having 251 (step S92).

  Next, FIG. 10 is a flowchart regarding processing in a node that is not an Originating node of a route search response message in replying a route search response message according to Embodiment 1 of the present invention. Specifically, in correspondence with FIG. 5 and FIG. 6, the processes performed in the nodes 5 and 2 that are Intermediate nodes and the node 1 that is the Target node of the route search response message are summarized.

  In FIG. 5, the operation corresponding to the flowchart of FIG. 10 will be described in the order of node 5, node 2, and node 1 in the order of receiving the route search response message.

  First, the operation of the node 5 will be described. The wireless unit 11 (5) of the node 5 having the real address 251 receives the route search response message returned from the node 7. Then, the route control unit 12 (5) of the node 5 sends the real address 271 of the node 7 that is the transmission source of the one-hop transmission of the received route search response message, and the real address 271 and logical address of the attached Originating node. 272 is used to add and set Forward Path (corresponding to the address information 26 shown in FIG. 6) in the path information table in the memory 13 (5) for which Reverse Path has already been set (step S101). This Forward Path information is used when a message for which a transmission request has been made is transmitted from the node 5 to the node 7 as an already determined transmission path.

  Then, the route control unit 12 (5) of the node 5 checks whether or not the real address 211 of the Target node added to the route search response message is the real address 251 indicating itself (step S102).

  In this case, since the node 5 is not a Target node and Step S102 is not true, the wireless unit 11 (5) of the node 5 does not change the content of the route search response message received from the node 7 and changes the memory. A route search response message is returned to the node 2 having the real address 221 in accordance with the Reverse Path toward the node 1 which is the target node entered in the route information table stored in 13 (5) (step S103). .

  Next, the operation of the node 2 will be described. The wireless unit 11 (2) of the node 2 having the real address 221 receives the route search response message returned from the node 5. Then, the path control unit 12 (2) of the node 2 receives the real address 251 of the node 5 that is the transmission source of the one-hop transmission of the received route search response message, and the real address 271 and logical address of the attached Originating node. 272 is used to set the Forward Path (corresponding to the address information 27 shown in FIG. 6) in the path information table in the memory 13 (2) for which the Reverse Path has already been set (step S101). This Forward Path information is used when a message for which a transmission request has been made is transmitted from the node 2 to the node 5 as an already determined transmission path.

  Then, the path control unit 12 (2) of the node 2 checks whether or not the real address 211 of the Target node added to the path search response message is the real address 221 indicating itself (step S102).

  In this case, since the node 2 is not the Target node and Step S102 is not true, the wireless unit 11 (2) of the node 2 does not change the content of the route search response message received from the node 5, and A route search response message is returned to the node 1 having the real address 211 in accordance with the Reverse Path toward the node 1 as the target node entered in the route information table stored in 13 (2) (step S103). .

  Next, the operation of the node 1 will be described. The wireless unit 11 (1) of the node 1 having the real address 211 receives the route search response message returned from the node 2. Then, the path control unit 12 (1) of the node 1 sends the real address 221 of the node 2 that is the transmission source of the one-hop transmission of the received route search response message, and the real address 271 and logical address of the attached Originating node. 272 is used to set Forward Path (corresponding to the address information 28 shown in FIG. 6) in the path information table in the memory 13 (2) (step S101). This Forward Path information is used when a message for which a transmission request has been made is transmitted from the node 1 to the node 2 as a transmission path that has already been determined.

  Then, the path control unit 12 (1) of the node 1 checks whether or not the real address 211 of the Target node added to the path search response message is the real address 211 indicating itself (step S102).

  In this case, since the node 1 is a Target node and step S102 is true, the route control unit 12 (1) of the node 1 determines that the route search response message has reached the node to be transmitted, Does not forward the route search response message.

  Then, the path control unit 12 (1) of the node 1 dequeues the message to be transmitted from the Waiting Queue secured in the area of the memory 13 (1). Further, the wireless unit 11 (1) of the node 1 transmits the dequeued message according to the Forward Path of the route information table (Step S104).

  After completion of the route search process, the address information 28 is finally held as a route information table in the memory 13 (1) of the node 1, and the route information table is stored in the memory 13 (2) of the node 2. The address information 27 is held as the path information table in the memory 13 (5) of the node 5, and the address information 24 is stored as the path information table in the memory 13 (7) of the node 7. Is held (see FIG. 6).

  As described above, in the address resolution method according to the first embodiment, in the route search process, the reverse for returning the route search response message while broadcasting the route search request message with the information of the source logical address added. Path is established.

  Further, the destination node that has received the route search request message unicasts the route search response message to which the logical address information of the destination node itself is added according to the Reverse Path, and uses the transmission route of the message to be transmitted. A certain Forward Path is established.

  Finally, the source node of the route search request message can obtain the logical address of the destination node simultaneously with the establishment of the transmission route by receiving the route search response message returned in response to this. . Accordingly, message transmission can be performed using the acquired logical address of the destination node and the established Forward Path.

  As described above, according to the first embodiment, the transmission route is obtained by performing the route search processing using the real address of the destination node without separately performing the address resolution processing and the route search processing as in ZigBee. As a result, the address of the destination node can be resolved. As a result, it is possible to reduce the number of broadcast message transmissions / receptions at each node constituting the ad hoc network. Reducing the number of transmission / reception has the effect of extending the battery replacement time for a battery-powered node.

  Further, when transmitting a message from the transmission source node to the destination node, the destination address and the transmission source set in the message frame are the same as those of ZigBee by using the logical address of the destination node resolved simultaneously by the route search processing. Can be specified by a logical address.

  For example, when IEEE 802.15.4 is used, the real address is 8 bytes, whereas the logical address is 2 bytes. Therefore, the area size required for addressing can be reduced by using the logical address. it can. As a result, it is possible to increase the amount of information that can be transmitted as one message from the application.

  In the first embodiment described above, the case where the nodes 1 to 7 are used and the node 1 and the node 7 communicate with each other as the intermediate node has been described. This is not the case. The address resolution method of the present invention is not limited to the seven nodes as shown in the first embodiment, the Originating node and the Target node need not be the node 1 and the node 7, and the Intermediate node As a result, the addresses of the Originating node and the Target node can be resolved in any communication path.

Claims (1)

In an ad hoc network having a plurality of nodes having real addresses and logical addresses, when sending a message from one source node to a destination node via one or more other relay nodes, In each of the plurality of nodes, from the state in which the logical address of the own node and the real addresses of all the nodes are known and the logical addresses of the other nodes other than the own node are unknown, the source node An address resolution method for obtaining a logical address,
The source node broadcasts a route search request message comprising first address information including its own logical address and real address and the real address of the destination node on the ad hoc network;
The relay node that is located between the source node and the destination node and that has received the route search request message includes a logical address and a real address of the source node included in the first address information, and the route Storing Reverse Path route information including the real address of the node that has transmitted the search request message, and broadcasting the route search request message on the ad hoc network;
The destination node includes, as a response to the route search request message received via the one or more relay nodes, second address information including its own logical address and real address, and the real address of the source node. Unicast the route search response message to the relay node that has transmitted the route search request message,
The relay node that has received the route search response message unicasts the route search response message to reverse the transmission route of the route search request message according to the stored Reverse Path route information,
The transmission source node establishes a message transmission route by reversing the transmission route of the route search request message and receiving the route search response message returned via the one or more relay nodes. And an address resolution method for obtaining a logical address of the destination node from the second address information included in the route search response message.

Images