JP3102079B2 - Route search method for wireless network system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wireless network system such as a wireless LAN for transmitting and receiving data wirelessly, and to a transmission route searching method for searching a transmission route of a message in this system.

[0002]

2. Description of the Related Art At present, various network systems for transmitting and receiving data between a plurality of terminal devices have been put into practical use, but all of these systems have been systems for transmitting and receiving data via a wired transmission line. For this reason, it is necessary to lay a transmission line between the terminal devices, which is troublesome and has a drawback that the arrangement of the terminal devices is fixed.

[0003]

Therefore, wireless data transmission / reception has been proposed. Conventional wireless data transmission / reception is a method in which a data transmitting station and a data receiving station directly communicate with each other. Therefore, communication was not possible within a range where radio waves could reach. Further, a repeater may be installed in order to transmit and receive data between terminal stations located at a longer distance, but there is a drawback that extra cost is required for the installation.

[0004] The present invention provides a wireless network system which solves the above-mentioned problems by installing a wireless terminal device in a network and transmitting data using another wireless terminal device as a relay station. An object is to provide an effective transmission path search method.

[0005]

According to the present invention, in a wireless network system, a direct search mode comprising the following procedures (1) to (5) for searching for a station capable of directly transmitting and receiving a message, and an indirect mode. Search for stations that can send and receive messages to
It is characterized by performing both of the indirect search mode consisting of the following steps (a) to (d).

(1) Station A constituting a wireless network
The polling message is transmitted individually to other stations.

(2) The other station (station B) that has received the polling message transmits a response message to station A.

(3) Station B stores the address of station A in its own direct communication table.

(4) Upon receiving the response message, the station A stores the address of the station B in its own direct communication table.

(5) All stations execute the operations of (1) to (4).

(A) The station A transmits a search message for a station not stored in the direct communication table to the station B whose address is stored in the direct communication table.

(B) The station B that has received the search message searches whether or not the address of the station is stored in the direct communication table or the indirect communication table. Reply.

(C) The station A that has received the reply stores this route in the indirect communication table.

(D) All stations execute the operations (a) to (c).

[0015]

According to the route search method of the present invention, a mode for searching for a station (wireless terminal device) capable of directly transmitting and receiving a message and a mode for searching for a route of a station for transmitting and receiving a message indirectly in a wireless network system. Equipped.

Further, when searching for a route of a station that cannot directly transmit and receive a telegram, the telegram is transmitted to a station that can directly transmit and receive the telegram, and the station stores a transmission route to a target station. Determine whether or not. If the station stores the transmission route to the station, the transmission may be performed via the station.

As described above, it is possible to search the transmission routes for all the stations only by accessing adjacent stations (where data can be directly transmitted and received).

In the route search method according to the present invention, the wireless network system includes a direct search mode for searching for a station capable of directly transmitting and receiving a message and an indirect search mode for searching for a route of a station for transmitting and receiving a message indirectly. The route of the indirectly transmitting / receiving station is searched in the range stored by the station capable of directly communicating. As a result, the network is not occupied for a long time to search for a route.

[0019]

FIG. 1 is a diagram showing a schematic configuration of a wireless network system according to an embodiment of the present invention. Wireless terminal devices (hereinafter, referred to as "stations") A to H constituting this system
Are arranged in an arbitrary arrangement, and are identified by addresses A to H, respectively. In the figure, stations within the range of the radio wave are connected to each other by a thin line. Such a wireless network system is, for example, a wireless P in which a POS terminal of a large store is wirelessly networked.
It is realized in an OS system or a wireless LAN system in which each node station is made wireless.

FIG. 2 is a diagram showing a configuration of the station (wireless terminal device). The wireless terminal device 1 is controlled by the controller 10. The controller 10 is constituted by a microcomputer and controls transmission and reception of data. A transceiver 11 and a data terminal device 13 are connected to the controller 10. The transceiver 11 is provided with an antenna 12. In the case of the wireless POS system, the data terminal device 13 is a POS terminal device main body. At the time of data transmission, the controller 10 edits the data output from the data terminal device 13 into a telegram and sends it to the transceiver 11. When receiving data, the controller 10 extracts data from the message received by the transceiver 11 and inputs the data to the data terminal device 13.

The communication route of each station is stored in a table as shown in FIG. This figure shows the table of station A. FIG. 3A shows a direct communication table (table 1). Since stations A and B can directly send and receive messages, stations B and C store B and C, respectively. FIG. 2B is a part of the indirect communication table (Table 2). This table stores message transmission / reception paths for stations other than the stations B and C. Among them, the H station has a plurality of transmission paths, and in this case, both of them are stored.

FIG. 4 is a diagram showing the structure of a message transmitted by each station. The message consists of the identification bit 21, the receiving station address 2
2, a transmission station address 23, a destination address 24, a transmission station address 25, transmission path information 26, and a data body 27. The identification bit 21 is a bit for identifying whether this message is a normal message or a search message.

When this bit is 0, it is a normal message.
The receiving station is a station that directly receives the message. The transmitting station is the station that directly transmitted this message. The destination is the station that should ultimately reach this message. The originating station is the station that edited this message and transmitted it first. The transmission path information 27 is information on a transmission path selected by the transmitting station from the table, and transmission and reception are repeated in the order of addresses written in the transmission path information 27. If the station is a POS terminal,
The data itself is composed of sales data and the like. In a command message described later, a command statement is written in the data body.

In such a wireless network system, the following processing is performed when searching for a message transmission path from one station to another station. In the following operation, the operation of the station A will be mainly described.

First, a direct search operation is performed. In this operation, the station A searches for a station capable of directly transmitting and receiving. In this case, the search message is transmitted to the stations B to H. Only the stations B and C receive the response. The A station writes the addresses B and C in the table 1. At the same time, B
The station and the station C write the address A in the table 1 of the own station.

Thereafter, stations B to G sequentially execute the same operation. Here, the reason why the H station does not perform is that all the other stations are transmitting the search message, and therefore all the station messages that can be directly transmitted and received are received.

After the above direct search operation, the indirect search operation is executed. First, the station A transmits a search message of a station other than the stations B and C to the stations B and C. Since the station D is stored in the table 1 of the station C, the station A receives a reply from the station C. As a result, it is understood that the message should be transmitted to the station D via the station C. In addition, it is understood that the station E may similarly transmit a message via the station B. By this operation, the station A writes the routes A → C → D and A → B → E into the table 2. The same operation is sequentially performed by the stations B to H.

Further, this operation is repeatedly executed. That is, in the second indirect search operation, station A is station B, station C
By transmitting the search message to the station, the transmission route to the stations F and G (written in the table 2 of the stations B and C) can be received. In the third indirect search operation,
By transmitting the search message to the stations B and C, the transmission path to the station H can be received.

In the second and subsequent indirect search operations, the indirect search message may be transmitted to the stations stored in the table 2 of each station. That is, in the second indirect search operation, the station A may send a message to the stations D and E to inquire about a communication route with another station (station H or the like) (the flowchart in FIG. 6 illustrates this method). Is adopted.).

The above search operation may be performed at any time, but is generally performed when a system is constructed or a new wireless terminal device is installed. Further, the program may be periodically executed at regular intervals.

FIGS. 5 to 7 are flowcharts showing the operation of each wireless terminal device.

FIG. 5 is a flowchart showing the direct search operation. First, 1 is added to the address of the own station (n1). That is, the address A is set to B, and the address B is set to C. A polling message is transmitted to this address station (n2). If there is a response from this station (n3), the address of this station is written directly into the search table (n4). Until the address ends, ie, H
This operation is repeated until a polling message is transmitted to the station. After that, the transmission result message is output (n6:
This output is performed to report to the operator by journal printing or the like. ), Permit the next station to search directly (n
7).

FIG. 6 is a flowchart showing the indirect search operation. First, the address of the station to be searched is initialized (n
10). The initial value is B for station A, and A for stations B and subsequent stations. It is searched whether this address is stored in Table 1 or Table 2 (n1
1). If not, an indirect search message is sent to the station stored in Table 1 or Table 2 (n12,
n13). This message is transmitted via the route stored in the table. When a route message is received from the station, the route data is written to table 2 (n14, n1).
5). N until the destination of Table 1 and Table 2 is completed
The operations from 12 to n15 are repeated. When the destinations in Tables 1 and 2 are completed (n16), the operations of n11 to n16 are repeated for the next new search destination station (address) (n1).
8). When this operation is completed for all the stations not written in the tables 1 and 2 (n17), the indirect search operation is permitted to another station (n19), and the operation is completed.

FIG. 7 is a flowchart showing the operation of the station in the receiving state. It waits until a polling message, an observation search message, or another message is received (n30, n31, n3).
2). When the polling message is received, the response message is transmitted with the address of the own station added (n3
3) Write the address of this station in table 1 (n3
4). When an indirect search message is received (n3
1) Search whether the address of the search destination is stored in the table 1 or 2 of the own station (n35), and if it is stored, return a response to which the route data is added (n36). . If the message is not stored, a reply message is returned (n37). Further, when another message is received (n32), the corresponding operation is executed (n38).

With this operation, it is possible to accurately search for a communication route with a distant station by referring to the table of the adjacent station. The destination of the indirect search message in FIG. 6 may be limited to the station stored in Table 1.

[0036]

According to the transmission route searching method of the present invention,
In a plurality of arbitrarily arranged wireless terminal devices, when setting a transmission route between two arbitrary stations, even if the terminal stations are distant from each other, the other wireless terminal devices automatically relay the relay stations. Since the setting can be made, communication between the remote terminal stations can be realized without a repeater. In this case, a communication route between stations capable of indirectly transmitting and receiving a message is searched in a range stored in a station capable of directly communicating, so that an efficient route search can be performed.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a wireless network system according to an embodiment of the present invention;

FIG. 2 is a diagram showing a configuration of a wireless terminal device used in the wireless network system;

FIG. 3 is a diagram showing a transmission route table stored in the wireless terminal device;

FIG. 4 is a diagram showing a configuration of a message transmitted in the wireless network system;

FIG. 5 is a flowchart showing the operation of the wireless terminal device;

FIG. 6 is a flowchart showing the operation of the wireless terminal device;

FIG. 7 is a flowchart showing the operation of the wireless terminal device.

[Explanation of symbols]

1 (1a to 1k) -wireless terminal device, 26-transmission route information, 30-table.

Claims (1)

(57) [Claims] In a wireless network system, a wireless terminal device capable of directly transmitting and receiving a message is searched for.
Both the direct search mode consisting of the steps (1) to (5) and the indirect search mode consisting of the following steps (a) to (d) for searching for a wireless terminal device capable of indirectly sending and receiving a message. A route search method for a wireless network system. (1) One wireless terminal A constituting a wireless network
Transmits the polling message individually to the other wireless terminal devices. (2) The other wireless terminal device B that has received the polling message
Transmits a response message to the wireless terminal device A. (3) The wireless terminal device B stores the address of the wireless terminal device A in its own direct communication table. (4) Upon receiving the response message, the wireless terminal device A stores the address of the wireless terminal device B in its own direct communication table. (5) All wireless terminal devices execute the operations of (1) to (4). (a) The wireless terminal device A transmits a search message for a wireless terminal device not stored in the direct communication table to the wireless terminal device B whose address is stored in the direct communication table. (b) The wireless terminal device B that has received the search message searches the direct communication table or the indirect communication table to determine whether or not the address of the wireless terminal device is stored. Reply the route. (c) The wireless terminal device A that has received the reply stores this route in the indirect communication table. (d) All wireless terminal devices execute the operations of (a) to (c).