JP2005064711A - Access point device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an access point device which can correspond to occurrence of a fault. <P>SOLUTION: The access point device AP1 is provided with a radio interface and a cable interface and has a relay function between a terminal STA linked by the radio interface and a host PC linked by the cable interface. The device is also provided with a terminal function which is linked to the other access point device AP2 as a terminal by the radio interface. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an access point device used for local wireless communication such as a wireless LAN, and more particularly to an access point device that can cope with occurrence of a failure.

  There is known a wireless LAN in which part or all of a LAN transmission path is realized wirelessly. In the wireless LAN shown in FIG. 3, a plurality of access point devices AP (AP1, AP2) having a wireless interface and a wired interface are provided, and the access point devices AP (AP1, AP2) are connected to the host PC by a wired interface. A link is established via the transmission line L, and the terminal STA (STA1, STA2) is linked wirelessly by a wireless interface. Thereby, the access point device AP exhibits a relay function between the terminal STA and the host PC.

  In FIG. 3, the access point device AP1 is linked to the terminal STA1, and the access point device AP2 is linked to the terminal STA2, so that the terminals STA1 and STA2 can communicate with the host PC. Here, a symbol is attached to each link. The link between the access point device AP1 and the host PC is A, the link between the access point device AP2 and the host PC is B, the link between the access point device AP1 and the terminal STA1 is C, and the link between the access point device AP2 and the terminal STA2 is D.

  As shown in FIG. 4, when the failure X1 occurs in the link C on the radio interface side of the access point device AP1, the terminal STA1 can recognize that the failure X1 has occurred in the link C, so that the terminal STA1 is connected to the access point device AP2. Link E can be performed and communication with the host PC can be resumed (however, one access point device AP can link with a plurality of terminals STA, respectively). That is, taking advantage of being wireless, the terminal STA1 can select and use any access point device AP1, AP2.

  However, when a failure X2 occurs in the link A on the wired interface side of the access point device AP1, the terminal STA1 cannot recognize that the failure X2 has occurred in the link A. Therefore, the terminal STA1 maintains the link C. In this case, the terminal STA1 cannot communicate with the host PC even though the link C, which is the wireless part, has no failure.

  The following measures are considered for the above problem.

  When the access point device AP1 recognizes that the failure X2 has occurred in the link A, the access point device AP1 forcibly disconnects the link C with the terminal STA1. The terminal STA1 can move to an action of searching for another access point device AP2 triggered by the link C being disconnected. Therefore, as shown in FIG. 4, the link E between the terminal STA1 and the access point device AP2 is established, and the terminal STA1 can resume communication with the host PC.

  Further, under the situation where the failure X2 occurs in the link A, it is desirable that the access point device AP1 does not permit the connection regardless of the connection request from any terminal STA. As a result, the terminal STA is prevented from being meaninglessly connected to the access point device AP1 in which the failure X2 has occurred in the link A on the wired interface side.

JP 2002-084286 A Japanese Patent Laid-Open No. 11-027267

  As shown in FIG. 4, in the situation where the failure X2 occurs in the link A, the access point device AP1 has a failure on its wired interface side, and the wireless interface side refuses the connection. There will be no means to communicate with.

  However, from the access point device AP1 to another device, particularly a management terminal (for example, a host PC) existing somewhere in the wired LAN portion or the wireless LAN portion, the current state of the access point device AP1 (occurrence of failure, You may want to be notified of the connection being refused.

  Accordingly, an object of the present invention is to provide an access point device that solves the above-described problems and can cope with the occurrence of a failure.

  In order to achieve the above object, the present invention provides a wireless interface in an access point device comprising a wireless interface and a wired interface, and having a relay function between a terminal linked by the wireless interface and a host linked by the wired interface. Thus, it has a terminal function for linking to other access point devices as a terminal.

  The relay function may be activated when there is no failure on the wired interface side, and the terminal function may be activated when a failure occurs on the wired interface side.

  The present invention exhibits the following excellent effects.

  (1) Excellent response to occurrence of failure.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

  As shown in FIG. 1, an access point device AP (AP1, AP2) according to the present invention includes a wireless interface and a wired interface, and is linked to a terminal STA (STA1, STA2) linked by the wireless interface and a wired interface. And a terminal function for linking as a terminal to another access point device AP through a wireless interface when a failure occurs on the wired interface side.

  The access point device AP has a function of detecting a failure on the wired interface side as usual, and when a failure has not occurred on the wired interface side, the relay function as the access point device AP is activated. When a failure occurs, the relay function is stopped and the terminal function is activated.

  Next, the internal configuration of the access point device AP according to the present invention will be described.

  As shown in FIG. 2, the access point device AP includes an antenna 31 for a radio interface, a modem unit 33 that modulates and demodulates a radio signal, a radio frame transceiver unit 34 that transmits and receives a radio frame carried in the radio signal, A protocol processing unit 35 that processes a wired / wireless LAN protocol, an Ethernet (registered trademark) frame transmission / reception unit 36 as a wired interface, a link detection unit 37 that detects a link state on the wired interface side, and a program A stored memory 38, a switching processing unit 32 for switching between a relay function and a terminal function, and a management database 39 are provided.

  The memory 38 stores AP software for operating as an original access point device and STA software for operating as a terminal. In this figure, the switching processing unit 32 for switching between the AP software and the STA software based on the detection result of the link detection unit 37 is indicated by a switch symbol.

  Next, the operation will be described.

  When all the links have no failure, the links A, B, C, and D are maintained as in the prior art described in FIG. 3, and the access point devices AP1 and AP2 are connected to the terminals STA1 and STA2 and the host PC. The relay function between is demonstrated.

  Further, when a failure X1 (see FIG. 4) occurs in the link C on the radio interface side of the access point device AP1, the terminal STA1 performs a link E with the access point device AP2 as in the prior art described in FIG. , Communication with the host PC can be resumed.

  As shown in FIG. 1, when a failure X2 occurs in the link A on the wired interface side of the access point device AP1, the switching processing unit 32 stores the memory of the access point device AP1 in which the failure X2 is detected by the link detection unit 37. By switching the AP software read from the STA software to the STA software, the relay function is stopped, and the terminal function linked as a terminal to the other access point device AP2 by the sound wireless interface is activated. Specifically, access point device AP2 is accessed to access point device AP2 by a method equivalent to terminals STA1 and STA2. That is, a frequency band to be used, a protocol for acquiring a channel, a code format for carrying information, a communication speed, and the like are made equal to those of the other terminals STA1 and STA2. Of course, each access point device AP has an address as a terminal STA in advance.

  As a result, the link F between the access point device AP1 and the access point device AP2 as a terminal is established, and the management terminal exists somewhere in the wired LAN portion or the wireless LAN portion from the access point device AP1 to another device. (The host PC in the illustrated example) can be notified of the current status of the access point device AP1 (occurrence of a failure, rejection of connection, etc.). Since the administrator who uses the management terminal can know that the failure X2 has occurred in the link A of the access point device AP1, the countermeasure can be rapidly advanced. In addition, since the link C disappears due to the relay function being stopped in the access point device AP1, the other terminal STA1 can perform the link E with the access point device AP2 and resume communication with the host PC. The terminal STA is not connected to the access point device AP1 meaninglessly.

It is a block diagram of the network using the access point apparatus which shows one Embodiment of this invention. It is an internal block diagram of the access point apparatus which shows one Embodiment of this invention. It is a block diagram of the network using the conventional access point apparatus. It is a block diagram of the network using the conventional access point apparatus.

Explanation of symbols

32 switching processing unit 37 link detection unit AP, AP1, AP2 access point device L transmission path PC host STA, STA1, STA2 terminal

Claims (2)

  An access point device having a wireless interface and a wired interface, and having a relay function between a terminal linked by the wireless interface and a host linked by the wired interface, is linked as a terminal to another access point device by the wireless interface An access point device having a terminal function. 2. The access point device according to claim 1, wherein the relay function is activated when there is no failure on the wired interface side, and the terminal function is activated when a failure occurs on the wired interface side.

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