JP2004363858A - Radio communication system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a radio communication system for detecting existence of a radio access point which is set by a different installing person. <P>SOLUTION: In the radio communication system, a user terminal receives a mark packet, loads a group of address information and attribute information, which are loaded on the mark packet, on a response packet and sends the response packet to a connected radio access point. A plurality of the radio access points receive the response packets from the user terminal connected to a means transmitting the mark packet to the user terminal, extract the group having attribute information which is the same as self-attribute information from the group of address information and attribute information, which are loaded on the received response packet, and detects address information which is not matched with address information of the radio access points having self-address information or attribute information which is the same as self-attribute information from address information that the extracted groups have. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a wireless communication system, and more particularly, to an ESS (Extended Service Set) having a plurality of wireless access points.
[0002]
[Prior art]
In recent years, communication services that allow access to the Internet from fixed locations such as corporate networks and home networks have become widespread, but in the future, they will be able to access the Internet freely while traveling in coffee shops, hotels, and public places. It is thought that nomadic communication services that can be accessed will spread.
[0003]
When this nomadic communication service is provided, a wireless access point is installed in a coffee shop, a hotel, a public place, or the like, and the wireless access point uses a wired LAN in which a Web server or the like exists and a wireless LAN in which a user terminal exists. A LAN is connected.
[0004]
In IEEE 802.11 which is a standard related to a wireless LAN, a communication area of each wireless access point is called a BSS (Base Service Set), and an area obtained by integrating a plurality of BSSs as a roaming area is an ESS (Extended Service Set: Extended Service Set). ).
[0005]
Since a plurality of wireless access points exist in the ESS, the user terminal in the ESS needs to select a wireless access point to be connected from the plurality of access points prior to communication.
[0006]
Therefore, in the conventional wireless communication system, the wireless access point uses attribute information (such as an ESSID) indicating which ESS the wireless access point is for so that the user terminal can make such a selection. A beacon packet carrying address information is periodically transmitted to the user terminal.
[0007]
Also, in a conventional wireless communication system, after a user terminal starts up and before accessing a wireless LAN, it first receives a beacon from each AP and receives attribute information (ESSID) included in the beacon. Etc.) and the address information of the wireless access point are displayed on the screen.
[0008]
[Non-patent document 1]
IEEE 802.11
[Problems to be solved by the invention]
However, the user terminal identifies the wireless access point based on the attribute information and the address information. Also, attribute information (such as ESSID) can be set freely at each wireless access point.
[0009]
For this reason, in the conventional wireless communication system, the wireless communication system is installed by a different person (hereinafter, referred to as a “different installer”) from the person to whom the self contracts or belongs (hereinafter, referred to as “authorized installer”). If the attribute information (such as ESSID) that is the same as the attribute information (such as ESSID) of the wireless access point installed by the authorized installer is assigned to the wireless access point, the user terminal is installed by the authorized installer. Wireless access points that have been installed cannot be distinguished from wireless access points installed by different installers.
[0010]
Therefore, in the conventional wireless communication system, since the user terminal cannot identify a plurality of wireless communication systems having the same attribute information (such as ESSID), the user terminal accesses the wireless access points installed by different installers. (Note that, in the wireless LAN application on the user terminal side, the wireless access point where the beacon packet arrived earlier in time, or the wireless with the strongest radio wave (that is, the closest radio wave) This is especially large when the access point is set to access).
[0011]
Therefore, in the conventional wireless communication system, there has been a problem that the user terminal accesses a wireless access point installed by a different installer and the secret information is stolen.
[0012]
In view of such circumstances, an object of the present invention is to provide a wireless communication system that can detect the presence of a wireless access point installed by different installers.
[0013]
[Means for Solving the Problems]
According to the present invention, the above-mentioned object is solved by the means described in the claims.
[0014]
According to a first aspect, in a wireless communication system having a plurality of wireless access points and at least one user terminal, the user terminal transmits a beacon packet loaded with a set of address information and attribute information to the plurality of wireless terminals. Beacon packet receiving means for receiving from each access point, a mounting means for mounting a set of address information and attribute information mounted on the beacon packet received by the beacon packet receiving means in a response packet, Response packet transmitting means for transmitting a response packet having a set of address information and attribute information to a connected wireless access point, the plurality of wireless access points transmitting the beacon packet to the user terminal. Beacon packet transmitting means for transmitting, and the response packet from the connected user terminal. Extracting a set having the same attribute information as its own attribute information from a set of address information and attribute information mounted on the response packet received by the response packet receiving means to be transmitted; Means and address information which does not match any of the address information of the wireless access point having the same attribute information as its own address information or its own attribute information from the address information of each of the sets extracted by the extracting means. And a detecting means for detecting.
[0015]
A second invention is a wireless communication system having a plurality of wireless access points and at least one user terminal, wherein the user terminals each receive first packets from the plurality of access points, A second packet transmitting means for transmitting a second packet in response to the first packet received by the first packet receiving means to a connected wireless access point, wherein the plurality of wireless access points are a first packet transmission means for transmitting the first packet to the user terminal, the number of first packets transmitted from the first packet transmitting means, the first packet transmission number of control into N _S per a predetermined time T Control means, second packet receiving means for receiving the second packet from a connected user terminal, and the predetermined time Computing the number N _S of the first packet wherein said first packet transmission means has transmitted per T, the number N _r of the second packet, wherein the second packet receiving means per predetermined time T has received, the difference between And a calculating means for performing the calculations.
[0016]
A third invention is, in a wireless communication system according to the first invention, the plurality of wireless access points, further, the number of labels packets transmitted from the labeled packet transmission means, N _S number per predetermined time T a labeled packet transmission speed control unit for controlling the, the number N _S of labels packets the labeled packet transmission unit per the predetermined time T has transmitted, the received response packet receiving unit per the predetermined time T responses A wireless communication system comprising: a calculation unit that calculates a difference between the number Nr of packets and a number _Nr .
[0017]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail.
[0018]
In the wireless communication system according to the first embodiment of the present invention, first, the user terminal sends beacon packets transmitted from wireless access points (AP0,..., APn) installed by authorized installers, respectively. To receive.
[0019]
The user terminal transmits the address information Add (APi) (i = 1,..., N) and the attribute information Inf (APi) (i = 1) of the source AP of the beacon packet included in the received beacon packet. ,..., N) are respectively recorded in the recording means.
[0020]
Then, the user terminal mounts all of the address information and the attribute information recorded in the recording unit in the response packet and transmits the response packet to the connected wireless access point.
[0021]
Also, the wireless access point reads out the address information and attribute information of each wireless access point mounted on the response packet from the user terminal, and reads the address information of the wireless access point having the same attribute information as its own attribute information. To detect.
[0022]
According to the wireless communication system according to the first embodiment of the present invention, information of all APs received by a user terminal including a wireless access point installed by a different installer is stored in an AP connected to the user terminal. Will be replied to.
[0023]
Therefore, the wireless access point connected to the user terminal can detect an AP installed by a different installer who falsifies the attribute information so as to allow the user terminal to access, using the information returned from the user terminal. .
[0024]
In the radio communication system according to a second embodiment of the present invention, a wireless access point, the number of labeled packets to be transmitted is controlled in the N _S per predetermined time T. Then, the wireless access point is calculated to calculate the number N _r of the response packet received from the user terminal per this the N _S and a predetermined time T, the difference.
[0025]
Therefore, according to the wireless communication system according to the second embodiment of the present invention, in the wireless access point, the number of response packets Nr exceeding the number Ns of beacon packets assumed by the AP installed by the authorized installer is assumed. Since it can be detected, it is possible to detect an AP installed by a different installer in which the same address information and attribute information are set as an AP installed by an authorized installer.
[0026]
【Example】
Next, a wireless communication system according to a first embodiment of the present invention will be described in detail with reference to the accompanying drawings.
[0027]
FIG. 1 is a diagram illustrating the wireless communication system according to the first embodiment of the present invention.
[0028]
As shown in FIG. 1, in the wireless communication system according to the first embodiment of the present invention, wireless access points (AP0,..., APn) are installed by authorized installers. , APn,..., APn communicates with a Web server or the like on a wired LAN.
[0029]
The user terminal a activates the terminal and, when wireless communication is enabled, receives the beacon packets transmitted from AP0,..., APn, respectively.
[0030]
The label packet i carries address information Add (APi) and attribute information Inf (APi) of the wireless access point (APi). Note that 1 ≦ i ≦ n.
[0031]
In the first embodiment of the present invention, ESSIDi is used as the attribute information Inf (APi), but the attribute information Inf (APi) may be any information as long as it can identify the ESS.
[0032]
The user terminal a that has received the beacon packet i stores Add (APi) mounted in the beacon packet i in the information storage memory, and further stores ESSIDi information in the information storage memory using Add (APi) as a key. Go.
[0033]
Then, the user terminal a mounts all the Add (AP) and ESSID information stored in the information storage memory in the response packet k and transmits the response packet k to the connected AP k. Note that 1 ≦ k ≦ n.
[0034]
In the wireless communication system according to the first embodiment of the present invention, it is assumed that the APx whose attribute information Inf (APx) is set to ESSIDk is installed by different installers.
[0035]
The APx transmits to the user terminal a a beacon packet x in which its own address information Add (APx) and its own attribute information Inf (APx) are mounted. Note that, as described above, the attribute information Inf (APx) = ESSIDk.
[0036]
When receiving the beacon packet x, the user terminal a accumulates the Add (APx) mounted on the beacon packet x in the information storage memory in the same manner as in the case of AP0 to APn, and further stores the Add (APx) as a key. Is stored in the information storage memory.
[0037]
Therefore, in the information storage memory of the user terminal a, information (Add (AP0), ESSID0) of the wireless access points (AP0 to APn) set up by authorized installers, (Add (APn), ESSIDn) ) As well as information (Add (APx), ESSIDk) of wireless access points (APx) installed by different installers.
[0038]
The user terminal a responds with information {(Add (AP0), ESSID0),... (Add (APn), ESSIDn), (Add (APx), ESSIDk)} stored in the information storage memory. The packet is all mounted on the packet k and transmitted to the connected APk. Note that, as described above, 1 ≦ k ≦ n.
[0039]
Assuming that the setting of the roaming function of the wireless access is set to OFF, the APk that has received the response packet from the user terminal a determines, from among a set of address information and attribute information having ESSIDk that is its own attribute information, , A set having the same attribute information as its own attribute information is extracted.
[0040]
In the first embodiment, (Add (AP0), ESSID0) and (Add (APX), ESSIDk) are extracted.
[0041]
AP0 detects address information that does not match its own address information Add (AP0) from Add (AP0) and Add (APx). In the first embodiment, Add (APk) is clearly detected.
[0042]
As described above, according to the first embodiment of the present invention, the user terminal a replies to all APs the information of all the APs that have been received. Therefore, according to the first embodiment of the present invention, it is possible to detect an AP having a different address but the same attribute information.
Therefore, according to the present invention, an AP installed by a different installer can be detected.
[0043]
FIG. 2 is a sequence diagram illustrating a method in which an AP detects wireless access interference from the number of response packets received in a wireless communication system according to a second embodiment of the present invention.
[0044]
In Example 2, AP0～APn of Figure 1 installed by authorized installer sets the number of labeled packets is controlled into N _S per predetermined time T.
[0045]
In the wireless communication system according to the second embodiment of the present invention, the same address information and attribute information as the address information and the attribute information of the APk installed by the authorized installer in the wireless access point APx of FIG. Is set by
[0046]
That is, in the second embodiment, the address information Add (APx) of APx is Add (APk), and the attribute information Inf (APx) of APx is ESSIDk.
[0047]
The APx transmits, to the user terminal a, a beacon packet x on which the Add (APx) = Add (APk) and the Inf (APx) = ESSIDk are mounted.
[0048]
The user terminal a that has received each of the beacon packets from AP0 to APx accumulates Add (APi) mounted on the beacon packet i in the information storage memory, and further adds Add (APi), as in the first embodiment. ) Is used as a key to store ESSIDi information in the information storage memory.
[0049]
Then, the user terminal a mounts all the Add (AP) and ESSID stored in the information storage memory in the response packet k, and transmits the response packet k to the connected AP k. Note that 1 ≦ k ≦ n.
[0050]
APk receives the response packet from the user terminal a, and counts the number N _r of the response packet received per predetermined time T.
[0051]
Then, APk includes a number N _S of labeled packets transmitted per predetermined time T, the number N _r of the response packet received per predetermined time T, the difference is calculated to detect the difference.
[0052]
As described above, according to the wireless communication system according to the second embodiment of the present invention, the number of beacon packets transmitted within a fixed time interval T and the number of received response packets can be compared and detected.
[0053]
Therefore, according to the second embodiment of the present invention, APk can detect that the user terminal a has received a beacon packet that has not been transmitted from itself.
[0054]
Therefore, according to the wireless communication system according to the second embodiment of the present invention, not only the case where the AP installed by a different installer has the same attribute information as the AP installed by the authorized installer, but also the same physical address , It is possible to detect an AP installed by the different administrator.
[0055]
【The invention's effect】
As described above, according to the present invention, an AP installed by a different installer can be detected, so that an AP installed by a different installer can be eliminated by some method.
[0056]
Therefore, according to the present invention, it is possible to prevent a user from erroneously trying to connect to an AP other than the AP installed by an authorized installer in wireless communication in a wireless LAN or the like.
[0057]
Therefore, according to the present invention, it is possible to prevent confidential information of a user from being stolen in wireless communication in a wireless LAN or the like.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating a wireless communication system according to a first embodiment of the present invention.
FIG. 2 is a sequence diagram illustrating a method of detecting wireless access interference from the number of response packets received by an AP in a wireless communication system according to a second embodiment of the present invention.
[Explanation of symbols]
User terminal a User terminal AP0 to APn AP connected by a legitimate installer
APx APs installed by different installers
APk AP connected to the user terminal
Inf (APi) Attribute information ESSIDi of APi ESSID of APi
Add (APi) Address information indicator packet of APi i Indicator packet of APi

Claims (3)

In a wireless communication system having a plurality of wireless access points and at least one user terminal,
The user terminal,
Beacon packet receiving means for receiving, from each of the plurality of access points, a beacon packet loaded with a set of address information and attribute information,
A mounting unit for mounting a set of address information and attribute information mounted on the beacon packet received by the beacon packet receiving unit on a response packet,
Response packet transmitting means for transmitting a response packet mounting a set of address information and attribute information in the mounting means to a connected wireless access point,
With
The plurality of wireless access points,
Beacon packet transmitting means for transmitting the beacon packet to the user terminal;
Response packet receiving means for receiving the response packet from a connected user terminal;
Extracting means for extracting a set having the same attribute information as its own attribute information from a set of address information and attribute information mounted on the response packet received by the response packet receiving means;
Detection of detecting address information that does not match any of the address information of the wireless access point having the same attribute information as the own address information or the own attribute information from the address information of the sets extracted by the extracting unit. Means,
Respectively,
A wireless communication system, comprising: In a wireless communication system having a plurality of wireless access points and at least one user terminal,
The user terminal,
First packet receiving means for receiving a first packet from each of the plurality of access points,
A second packet transmitting means for transmitting a second packet responding to the first packet received by the first packet receiving means to a connected wireless access point,
With
The plurality of wireless access points,
First packet transmitting means for transmitting the first packet to the user terminal,
The number of the first packet sent from the first packet transmitting means, a first packet transmission speed control unit for controlling into N _S per predetermined time T,
Second packet receiving means for receiving the second packet from a connected user terminal,
A number N _{S of} first packets transmitted by the first packet transmitting means per the predetermined time T, a number N _{r of} second packets received by the second packet receiving means per the predetermined time T, Calculating means for calculating the difference between
Respectively,
A wireless communication system, comprising: The wireless communication system according to claim 1,
The plurality of wireless access points further include:
The number of labeled packets transmitted from the labeled packet transmitting means, and a labeled packet transmission speed control unit for controlling into N _S per predetermined time T,
Computing the number N _S of labels packets the labeled packet transmission unit per the predetermined time T has transmitted, the number N _r of the response packet in which the response packet receiving unit received per predetermined time T, the difference in Calculation means for
Respectively,
A wireless communication system, comprising:

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