JP3848281B2 - RADIO COMMUNICATION SYSTEM, RADIO TERMINAL DEVICE, ACCESS POINT DEVICE AND MANAGEMENT DEVICE, PROGRAM, AND RADIO COMMUNICATION METHOD USED IN THE RADIO COMMUNICATION SYSTEM - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a wireless communication system such as a wireless local area network (LAN) in which a communication network communicates with a terminal using wireless communication, a wireless terminal device used in the wireless communication system, an access point device, and management The present invention relates to an apparatus, a program, and a wireless communication method.
[0002]
[Prior art]
As a flow of personal communication, network access using a wireless local area network (LAN) has become widespread. Wireless LAN includes an ad hoc mode in which terminals communicate directly with each other and an infrastructure mode in which terminals communicate with other terminals and servers via an access point.
[0003]
In the infrastructure mode, the access point periodically broadcasts information as a beacon. The terminal checks the information and tries to connect to the access point.
[0004]
The following procedure is defined in “INTERNATIONAL STANDARD ISO / IEC 8022-11” which is a wireless LAN standard.
[0005]
(1) The access point periodically transmits beacon frames. The beacon frame includes an information element called SSID (Service Set IDentity) or ESS-ID (Extended Service Set IDentity), and the name of the group to which the access point belongs is written. The following is an example where ESS-ID is used for simplicity.
[0006]
(2) After receiving the above beacon frame, the terminal transmits an association request frame when it wishes to connect to the access point that transmitted the beacon frame. This frame includes the ESS-ID.
[0007]
(3) Upon receiving the association request frame, the access point examines the request contents and decides whether to permit the connection. The condition at this time includes that the ESS-ID in the association request frame matches the ESS-ID held by the access point. As a result of the examination, when it is determined that the terminal association is permitted, the access point returns an association response frame to the terminal and negotiates other communication conditions.
[0008]
(4) In the above examination of ESS-ID, when the terminal enters a value of ESS-ID = “ANY” in the association request frame, it is common that the access point permits access as an exception.
[0009]
Now, in the wireless LAN providing service in the public area that has begun to spread in recent years, an Internet connection via a wireless LAN is provided to a terminal such as a personal computer using an infrastructure mode. Of these, ESS-ID = "ANY" is allowed for services that can be accessed by anyone for free, while ESS-ID is determined for services that can be connected by membership. Value (or symbol).
[0010]
When performing such a wireless LAN providing service, there are the following two problems.
[0011]
The first is a radio frequency limitation problem. Since the spot service is developed in a place where many people gather, in a crowded place, a plurality of service providers may be concentrated and several frequencies may be used simultaneously. Even when one service provider monopolizes, there are cases where a service is provided using a plurality of wireless channels in order to provide services to as many customers as possible. Specifically, in the 2.4 GHz band, for example, 3 to 4 types of channels, and in the 5.2 GHz band, 4 types of channels can be used at maximum. The maximum transmission rate at the radio level in the 5.2 GHz band is as high as 54 megabits per second, but the effective throughput seen from the application is about half, accommodating 100 user terminals and 1 megabit per second for each user. Again, all four channels are required to provide a degree of throughput.
[0012]
In such a situation, a user terminal wants to receive service at the spot. The user terminal cannot know in advance information about which frequency and which channel the service provider that it wants to enter is providing. Therefore, tentatively, all 2.4 GHz band channels were examined, and all 5.2 GHz band channels were examined, and among them, the channel including the ESS-ID indicating the service provider desired to connect was confirmed. Must be connected on. Since the use frequency of wireless LAN will be expanded to 4.9 GHz in the future, the number of wireless channels to be examined is increasing. This procedure is very troublesome.
[0013]
In the spot service, the same ESS-ID is generally used for providing a specific service. However, when performing roaming between providers, a specific service may be provided by a plurality of ESS-IDs. However, in the case of the current spot service, the ESS-ID is set in the terminal by the user's manual input. The case where the value of the ESS-ID is changed due to the roaming is not considered at all, and the user has to change the ESS-ID as appropriate in order to receive the roaming service.
[0014]
The second is a problem in the case where a certain spot service provider in the above owns a plurality of channels and provides services. From the terminal, it is unclear which of a plurality of channels should be used. Therefore, the terminal selects one from a plurality of channels in accordance with the arbitrary rules of the terminal. In the simplest case, it is conceivable to select from the order in which the channels are examined, for example, the channel having the smaller frequency. Such a selection method is the same for terminals having the same wireless LAN module. As a result of a plurality of terminals selecting channels using the same method in this way, even if there are a plurality of radio channels of a certain spot service provider, terminals receiving services only on a specific channel are concentrated. As a result, there is a risk that the efficient service that should originally be intended cannot be provided.
[0015]
A system that centrally manages to which access point a terminal currently belongs is known (for example, see Patent Document 1). However, in the system disclosed in Patent Document 1, all access points have the same ID, and the user can be sure to receive a connection service regardless of which channel of which access point is accessed. Only applies.
[0016]
[Patent Document 1]
JP 2000-232455 A
[0017]
[Problems to be solved by the invention]
The conventional standard wireless LAN specifications cannot provide an efficient service as described above when performing a spot service.
[0018]
The present invention has been made in consideration of such circumstances, and an object of the present invention is to efficiently provide communication services using a plurality of radio channels in overlapping areas.
[0019]
[Means for Solving the Problems]
In order to achieve the above object, the present invention communicates with a radio terminal apparatus using a radio terminal apparatus and a plurality of radio channels each belonging to one of a plurality of service groups and assigned with an identifier. In the wireless communication system including the communication network to be transmitted, the wireless terminal device transmits inquiry information indicating one of the plurality of service groups using the wireless channel. In the communication network, the inquiry information is received, the radio channel belonging to the service group indicated in the received inquiry information is selected, and the selected radio channel and the selected radio channel are selected. Response information indicating at least one of the assigned identifiers is generated, and the response information is transmitted to the wireless terminal device using the wireless channel used for transmitting the inquiry information. The wireless terminal device receives the answer information transmitted from the communication network.
[0020]
The wireless terminal device transmits and receives inquiry information and answer information using a method of transmitting and receiving via a wireless channel whose identifier remains unknown to the wireless terminal device. The response information indicates at least one of the radio channel belonging to the service group indicated in the inquiry information on the radio terminal device side and the identifier assigned to the selected radio channel. By taking such means, the wireless terminal device can perform regular access to the communication network based on the information notified in the response information.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0022]
FIG. 1 is an overall configuration diagram of a wireless communication system according to the present embodiment.
As shown in FIG. 1, the wireless communication system according to the first embodiment includes an access point device 1, a management server 2, a wireless terminal device 3, and a network 4. The access point device 1 can communicate with the management server 2 via the network 4. The access point device 1 can communicate with the wireless terminal device 3 via a wireless channel.
[0023]
As shown in FIG. 1, the access point device 1 includes a plurality of wired ports 11, a plurality of wireless interfaces (wireless IFs) 12, a plurality of wireless antennas 13, a control unit 14, and a switch unit 15. Note that the number of the wired ports 11 may be an arbitrary number of one or more, but here, it is assumed that two are provided. In addition, the number of the wireless antennas 13 and the wireless interfaces 12 may be an arbitrary number of two or more, but here, four each are provided.
[0024]
The wired port 11 transmits and receives packets transmitted via the network 4.
[0025]
The wireless interface 12 performs wireless communication with the wireless terminal device 3 using the wireless antenna 13. The four radio interfaces 12 use different radio channels. The four radio channels used by the radio interface 12 are generally assumed to have the same frequency band. That is, for example, it is assumed that four channels of 5.2 GHz band are used. However, the same frequency band is not necessarily required unless there is complete frequency overlap. Channels of different frequency bands may be used together. For example, the two radio channels may use the 2.4 GHz band, and the other two radio channels may use the 5.2 GHz band. Absent.
[0026]
The areas covered by the plurality of wireless interfaces 12 overlap. Therefore, the wireless terminal device 3 can receive any of the four wireless channels in the area.
[0027]
The control unit 14 performs processing for connecting the wireless terminal device 3 to the network 4 via the access point device 1.
[0028]
The switch unit 15 connects the wired port 11 and the wireless interface 12 to the control unit 14.
[0029]
FIG. 2 is a block diagram showing a detailed configuration of the access point device 1. 2 that are the same as those in FIG. 1 are denoted by the same reference numerals. In FIG. 2, only one wired port 11 and one wireless interface 12 are shown.
[0030]
As shown in FIG. 2, the wired port 11 includes a packet routing unit 111. The radio interface 12 includes an antenna duplexer 121, a radio receiver 122, a radio transmitter 123, and a frequency / channel setting unit 124. The control unit 14 includes a frame reception unit 141, an ESS-ID confirmation unit 142, a management server packet creation unit 143, a reply packet interpretation unit 144, a terminal message creation unit 145, and a frame generation unit 146.
[0031]
The radio signal radiated from the radio terminal device 3 is converted into an electric signal by the radio antenna 13 and input to the radio reception unit 122 via the antenna duplexer 121. The radio reception unit 122 extracts a signal of a required radio channel from the input signal. The signal extracted by the wireless reception unit 122 is input to the frame reception unit 141 of the control unit 14 via the switch unit 15.
[0032]
The frame reception unit 141 extracts a packet after synthesizing the signal frame output from the wireless reception unit 122. The frame receiving unit 141 confirms the type of the extracted packet. The frame reception unit 141 gives a packet for normal data communication to the packet routing unit 111 via the switch unit 15. When the packet is the first-level association request message and the value of ESS-ID is “ANY”, the frame receiving unit 141 sends the contents of this message to the ESS-ID confirmation unit 142. The ESS-ID confirmation unit 142 classifies the received message into an inquiry message, which will be described later, and a message that is not, and analyzes the content of the message only for the former. Then, the analyzed contents are transferred to the packet creation unit 143 for the management server. The packet creation unit 143 for the management server creates an inquiry packet for sending the information given from the ESS-ID confirmation unit 142 to the management server 2. The ESS-ID confirmation unit 142 passes the created inquiry packet to the packet routing unit 111 via the switch unit 15.
[0033]
The packet routing unit 111 confirms the destination of the packet passed from the control unit 14 and sends the packet to the network 4 if the destination is on the network 4 side. If the destination of the packet is the wireless terminal device 3 in the same wireless area as the transmission source, the packet routing unit 111 returns this packet to the frame generation unit 146 via the switch unit 15. Accordingly, the packet routing unit 111 sends the inquiry packet passed from the packet creation unit 143 for the management server to the network 4. The packet routing unit 111 preferably routes the inquiry packet with priority over the packet passed from the frame reception unit 141.
[0034]
The management server packet creation unit 143 transmits not only the inquiry packet but also a packet for notifying the management server 2 of periodic traffic information on the wireless interface 12 and information on the positional relationship of the wireless antenna 13. Have That is, the management server packet creation unit 143 acquires the traffic information monitored by the frame reception unit 141, creates a packet indicating the traffic information, and transmits the packet to the management server 2.
[0035]
By the way, the information related to the positional relationship of the wireless antenna 13 is generally found to be a result of carrier sense performed between the wireless antennas 13 of the access point device 1 because it is generally very difficult to transmit physical installation information. A method of interpreting that the distance between the areas is closer as the electric field strength increases by reporting the received electric field strength of a specific frame (such as a beacon) from each access point device 1 to the management server 2. is there. When this method is adopted, the management server packet creation unit 143 creates a packet indicating the received electric field strength and transmits it to the management server 2.
[0036]
The packet routing unit 111 receives a packet that has arrived via the network 4. The packet routing unit 111 classifies the reply packet transmitted from the management server 2 according to the inquiry packet and other packets, passes the former packet to the reply packet interpreter 144, and sends the latter packet to the frame. The data is passed to the generation unit 146. The reply packet interpreter 144 interprets the contents of the reply packet and passes the interpretation result to the terminal message creator 145. The terminal message creation unit 145 creates a reply message indicating the information passed from the reply packet interpretation unit 144, and passes this reply message to the frame generation unit 146. The frame generation unit 146 generates a signal obtained by framing the packet passed from the packet routing unit 111 and the reply message passed from the terminal message creation unit 145, and transmits this signal via the switch unit 15 through the wireless interface 12. To part 123.
[0037]
The wireless transmission unit 123 converts the signal output from the frame generation unit 146 into a signal for transmission through a predetermined wireless channel, and then supplies this signal to the wireless antenna 13 via the antenna duplexer 121. As a result, the signal output from the frame generation unit 146 is wirelessly transmitted from the wireless antenna 13.
[0038]
The frequency / channel setting unit 124 sets a wireless channel that the wireless reception unit 122 and the wireless transmission unit 123 transmit and receive. The frequency / channel setting unit 124 is used not to change the radio channel frequently during operation, but to perform setting at the time of initialization, for example.
[0039]
FIG. 3 is a block diagram showing the configuration of the management server 2.
As shown in FIG. 3, the management server 2 includes a wired port 21, a packet reception unit 22, a reception packet interpretation unit 23, a correspondence table 24, a transmission packet creation unit 25, and a packet transmission unit 26.
[0040]
For example, a general-purpose server device can be used as the management server 2. The packet reception unit 22, the reception packet interpretation unit 23, the transmission packet creation unit 25, and the packet transmission unit 26 can be realized by causing a processor mounted on the server device to execute a program. The management server 2 may have the above program installed in advance, or may be recorded on a removable recording medium such as a CD-ROM, or distributed through the network 4 and the program may be distributed. It may be installed as appropriate.
[0041]
A packet transmitted to the management server 2 via the network 4 is captured by the wired port 21 and passed to the packet receiving unit 22. The packet receiving unit 22 receives a packet passed from the wired port 21. The packet receiving unit 22 confirms whether or not the received packet is a valid packet, and passes the valid packet to the received packet interpretation unit 23. The received packet interpretation unit 23 interprets the contents of the passed packet. When the received packet is an inquiry packet, the reception packet interpretation unit 23 displays information such as the wireless channel belonging to the service group indicated in the inquiry packet and the ESS-ID assigned to the wireless channel in the correspondence table 24. Get from. The reception packet interpretation unit 23 passes the information acquired from the correspondence table 24 to the transmission packet creation unit 25.
[0042]
The transmission packet creation unit 25 creates a response packet indicating the information passed from the reception packet interpretation unit 23 and passes this response packet to the packet transmission unit 26. The packet transmission unit 26 transmits the received answer packet to the access point device 1.
[0043]
The correspondence table 24 is a database describing information about the access point device 1. Specifically, for example, as shown in FIG. 4, the ID number of each radio interface 12, the radio channel used in each radio interface 12, and the ESS− assigned to the radio channel used in each radio interface 12. The ID is described in association with it.
[0044]
FIG. 5 is a block diagram showing a configuration of the wireless terminal device 3.
As shown in FIG. 5, the wireless terminal device 3 includes a wireless antenna 31, an antenna duplexer 32, a wireless reception unit 33, a frame reception unit 34, an application reception unit 35, a screen display unit 36, an application transmission unit 37, a subscription carrier ID. A subscription ISP ID management unit 38, an in-house group ID management unit 39, a selection unit 40, an ESS-ID setting unit 41, a frame generation unit 42, a wireless transmission unit 43, and a frequency / channel setting unit 44 are included.
[0045]
The radio wave radiated from the access point device 1 is converted into an electric signal by the radio antenna 31 and input to the radio reception unit 33 via the antenna duplexer 32. The radio reception unit 33 extracts a signal of a required radio channel from the input signal. The signal extracted by the wireless reception unit 33 is input to the frame reception unit 34.
[0046]
The frame receiving unit 34 extracts a packet after synthesizing the signal frame output from the wireless receiving unit 33. The frame receiving unit 34 confirms the type of the extracted packet and passes a normal data packet to the application receiving unit 35. The application receiving unit 35 performs an application level process on the data packet to be transferred, and passes necessary information out of the obtained information to the screen display unit 36. The screen display unit 36 performs display on the screen based on the passed information.
[0047]
The screen display unit 36 receives an application operation by the user and passes a command or the like indicating the content of the operation to the application transmission unit 37. The application transmission unit 37 creates transmission data based on the passed command or the like, and passes this transmission data to the frame generation unit 42.
[0048]
The subscription carrier ID / subscription ISP ID management unit 38 holds and manages the name of the communication carrier to which the user of the wireless terminal device 3 is subscribed and an identifier related to the ISP. The in-house group ID management unit 39 holds and manages the identifiers of departments such as “Research and Development Department”. Note that the information held and managed by the subscribing carrier ID / subscriber ISP ID management unit 38 and the in-house group ID management unit 39 changes for each user when the wireless terminal device 3 is shared by a plurality of users. Therefore, in such a case, the subscribing carrier ID / subscribing ISP ID management unit 38 and the in-house group ID management unit 39 may individually manage information for each user.
[0049]
The selection unit 40 selects information to be used for the current access from the information held and managed by the subscription carrier ID / subscription ISP ID management unit 38 and the in-house group ID management unit 39. That is, the selection unit 40 determines whether the identifier to be used for the current access is a group name in the workplace or an identifier such as a general ISP, and moreover, a plurality of candidates for the identifier of the group name or ISP in the workplace. If there is, determine which one should be used and select the corresponding information. The above determination may be automatically made according to a predetermined rule, but since this is not easy, the user may be inquired as necessary. The selection unit 40 passes the selected information to the ESS-ID setting unit 41 and the frame generation unit 42, respectively.
[0050]
The ESS-ID setting unit 41 passes the ESS-ID value to be used to the frame generation unit 42. When the ESS-ID value to be used is unknown, the ESS-ID setting unit 41 passes “ANY” as the ESS-ID value to the frame generation unit 42. By the way, when the response message indicating the ESS-ID is received, the frame receiving unit 34 passes the value of the ESS-ID indicated in the response message to the ESS-ID setting unit 41. The ESS-ID setting unit 41 sets the value passed in this way as the value of the ESS-ID to be used, and passes it to the frame generation unit 42. When a plurality of ESS-ID values are indicated in the reply message, the ESS-ID setting unit 41 controls the selection of any of the plurality of values. When the radio channel to which the newly set ESS-ID is assigned is unknown, the ESS-ID setting unit 41 sends the carrier sense of the radio channel having the ESS-ID value to the radio reception unit 33. Ask.
[0051]
When receiving the above request, the wireless reception unit 33 performs carrier sense. The radio reception unit 33 passes the carrier sense result to the frequency / channel setting unit 44 via the frame reception unit 34. Meanwhile, when a response message designating a radio channel is received, the frame receiving unit 34 notifies the frequency / channel setting unit 44 of the radio channel designated by this response message. The frequency / channel setting unit 44 transmits / receives the wireless channel determined to be usable based on the carrier sense result or the wireless channel specified by the response message to the transmission / reception unit. To control.
[0052]
The frame generation unit 42 passes the transmission data passed from the application transmission unit 37 to the wireless transmission unit 43 in the form of a frame to be output to the wireless channel. In addition, the frame generation unit 42 creates various association request messages and passes the association request message to the wireless transmission unit 43. The wireless transmission unit 43 converts the signal passed from the frame generation unit 42 into a signal for transmission through a predetermined wireless channel, and then supplies this signal to the wireless antenna 31 via the antenna duplexer 32. As a result, the signal output from the frame generation unit 42 is wirelessly transmitted from the wireless antenna 31.
[0053]
(First embodiment)
Hereinafter, an operation in the first embodiment of the wireless communication system configured as described above will be described.
FIG. 6 is a sequence diagram of radio access in the first embodiment. FIG. 7 is a flowchart of the management server 2 in the first embodiment.
[0054]
In the first embodiment, the user of the wireless terminal device 3 tries to receive a service provided by an ISP or the like to which the user has already subscribed, but the user sets the ESS-ID of the wireless channel used for the service. It assumes the situation of not knowing.
[0055]
The wireless terminal device 3 has information such as an ISP to which the user has access rights and usable communication carriers, which are explicitly shown in the form of a connection icon on the terminal, for example. Since the information is already present in the vicinity of the wireless LAN card, it is not necessary for the user to set the information such as the provider again in consideration of the spot service.
[0056]
It is assumed that the user instructs access to the wireless terminal device 3 after designating company A as an ISP or the like. In response to this, the wireless terminal device 3 creates an initial association request message. In this association request message, information (name, etc.) of the designated ISP and communication carrier is described as a service group. That is, “Company A” is described in the association request message here. By the way, at this time, the value of ESS-ID is unknown. Therefore, the ESS-ID of the above association request message is set to “ANY”. This type of association request message is used as an inquiry message in the first embodiment. Then, the wireless terminal device 3 wirelessly transmits the inquiry message created in this way to the access point device 1 (E1 in FIG. 6).
[0057]
The wireless channel used for sending the inquiry message may be any of the four wireless channels. For example, if a radio channel that can receive a beacon frame first is selected and used, the time until the service starts can be shortened. In the example of FIG. 6, the wireless channel Ch1 is used.
[0058]
The inquiry message is received by the one corresponding to the wireless channel Ch1 among the plurality of wireless interfaces 12 of the access point device 1 and passed to the control unit 14 via the switch unit 15.
[0059]
When the control unit 14 confirms that the value of the ESS-ID is “ANY”, the content of the message is analyzed. When the control unit 14 confirms that “Company A” is described as the name of the ISP, the name information “Company A” and the identifier of the wireless interface 12 or the wireless antenna 13 accessed by the wireless terminal device 3 are displayed. And an inquiry packet including the identifier of the wireless terminal device 3 is created. The control unit 14 sends the created inquiry packet to the network 4 via the switch unit 15 and the wired port 11 and sends it to the management server 2 (E2 in FIG. 6).
[0060]
When the inquiry packet arrives via the network 4, the management server 2 executes the processing shown in FIG.
The management server 2 first receives an inquiry packet that has arrived via the network 4 in step ST1. Next, in step ST2, the management server 2 checks whether or not the inquiry packet is valid. If the inquiry packet is not valid, the management server 2 ignores the inquiry packet and ends this process.
[0061]
If the inquiry packet is valid, the management server 2 interprets the contents of the inquiry packet in step ST3. In step ST4, the management server 2 acquires from the correspondence table 24 the ESS-ID corresponding to the name of the ISP or the like described in the inquiry packet.
[0062]
Subsequently, in step ST5, the management server 2 confirms whether or not the acquisition of the ESS-ID is successful. If successful, in step ST6, the management server 2 creates the reply packet indicating the acquired ESS-ID. If acquisition of the ESS-ID fails, the management server 2 creates a reply packet indicating notification information for notifying failure in step ST7. Note that, in both step ST6 and step ST7, the management server 2 includes the identifier of the wireless interface 12 or the wireless antenna 13 and the identifier of the wireless terminal device 3 included in the inquiry packet in the reply packet.
[0063]
In step ST8, the management server 2 sends the reply packet created in step ST6 or step ST7 to the network 4 toward the access point device 1 (E3 in FIG. 6).
[0064]
In the access point device 1, when the answer packet arrives via the network 4, the answer packet is fetched by the wired port 11 and passed to the control unit 14 via the switch unit 15. The control unit 14 interprets the content of the reply packet and extracts the ESS-ID or notification information indicated in the reply packet. Then, the control unit 14 creates a reply message including the extracted ESS-ID or notification information, and transmits the reply message to the wireless terminal device 3. At this time, the wireless channel corresponding to the identifier of the wireless interface 12 or the wireless antenna 13 indicated in the reply packet is used, and the destination of the reply message is the identifier of the wireless terminal device 3 included in the reply packet. Therefore, a reply message is sent to the wireless terminal device 3 that has transmitted the inquiry message using the same wireless channel Ch1 to which the inquiry message is transmitted (E4 in FIG. 6).
[0065]
Thus, the wireless terminal device 3 can receive the reply message transmitted from the access point device 1 by waiting on the wireless channel used to transmit the inquiry message.
[0066]
When receiving the reply message, the wireless terminal device 3 confirms which of the ESS-ID and the notification information indicating the failure is included. If the notification information indicating the failure is included, the wireless terminal device 3 has not been able to acquire the ESS-ID necessary for receiving the desired service, so that the user is notified accordingly. To do.
[0067]
If the reply message includes ESS-ID, the wireless terminal device 3 searches for a wireless channel having this ESS-ID by carrier sense (E5 in FIG. 6). If a corresponding wireless channel is found by this, the wireless terminal device 3 sends an association request message in which the ESS-ID included in the answer message is appropriately set to the wireless channel (in FIG. 6). E6). In the example of FIG. 6, since the wireless channel Ch4 has been found as the corresponding wireless channel, an association request message is transmitted using this wireless channel Ch4.
[0068]
Since this association request message is a legitimate message, the access point apparatus 1 performs a connection process (E7 in FIG. 6) with an ISP or the like according to a well-known procedure, and communicates between the wireless terminal apparatus 3 and the ISP or the like ( E8) in FIG. 6 is started.
[0069]
Even if the wireless channel found as a result of the carrier sense is the same as the wireless channel used for transmitting the inquiry message, the wireless terminal device 3 transmits the association request message as described above. At this time, the association request repeatedly arrives at the access point device 1, but the subsequent ESS-ID depends on whether it is a specific value (for example, a value for company A) or "ANY". There is no inconvenience for changing the processing.
[0070]
As described above, according to the first embodiment, even if the wireless terminal device 3 does not know an appropriate ESS-ID, a service group such as the name of a subscribed ISP or communication carrier is added. An appropriate ESS-ID value can be taught to the wireless terminal device 3 on the basis of the information to be pointed, so that association can be performed appropriately. At this time, the wireless terminal device 3 appropriately accesses the caught wireless channel and transmits an inquiry message, and performs carrier sense for finding a wireless channel having the ESS-ID notified by the reply message. This can be realized simply by adding only simple functions to the configuration of the existing wireless terminal device.
[0071]
By the way, since the ESS-ID can be appropriately notified to the wireless terminal device 3 as described above and the association by this ESS-ID can be performed, the first embodiment is operated in the following form. This makes it possible to provide a roaming service efficiently.
[0072]
Here, company A is using ESS-ID # A on radio channel Ch4 and company E, which is affiliated with company A, is using ESS-ID # E on radio channel Ch2. Will be described as an example.
[0073]
If the wireless terminal device 3 cannot find a wireless channel that matches the ESS-ID specified in the reply message, wireless access is not possible.
[0074]
The following two causes can be considered as a cause of such a situation.
The first cause is that the radio terminal device 3 is not adapted to the radio frequency band to which the radio channel having the designated ESS-ID belongs. For example, this is the case when the ESS-ID for the 2.4 GHz band radio channel is specified even though the wireless terminal device 3 can only access the 5.2 GHz band.
[0075]
The second cause is that the radio channel having the designated ESS-ID cannot be accessed because the radio wave intensity in the radio terminal device 3 is weak. Even if the area is near, this is a case where it becomes a so-called “hidden terminal” due to the influence of an obstacle or the like.
[0076]
In the situation where the same service is provided by a plurality of radio channels in the same area as in the specific example here, the above-described problems can be dealt with by the following two measures.
[0077]
First, the first treatment in the present embodiment will be described.
The wireless terminal device 3 receives the notification of ESS-ID # A to receive the service of the company A and performs carrier sense regarding the ESS-ID # A, but cannot find the corresponding wireless channel Ch4. To do. In this case, the wireless terminal device 3 transmits the inquiry message again. At this time, since the wireless terminal device 3 may be moving, the wireless channel and the access point device 1 used for transmitting the inquiry message may be changed. At this time, the value “ANY” is described in the ESS-ID field of the inquiry message. In addition, the value “ESS-ID # A” is also described as the value of the ESS-ID that has recently failed to be accessed.
[0078]
In the access point device 1, the inquiry packet created based on the inquiry message includes the value of the failed ESS-ID.
[0079]
The management server 2 obtains an appropriate ESS-ID by comprehensively considering the identifier of the wireless terminal device 3 that has attempted access in the past and the failed ESS-ID, or the current position of the wireless terminal device 3. To do.
[0080]
In the case of the above specific example, if the wireless terminal device 3 is not moving, for example, the ESS-ID # E of the company E affiliated with the company A is acquired, and a reply packet indicating this is transmitted.
[0081]
The wireless terminal device 3 can obtain the ESS-ID # E of company E by receiving the response message transmitted from the access point device 1 based on the above response packet. If the wireless channel Ch2 having this ESS-ID # E can be found, it is possible to receive the same service as the company A by the company E using the wireless channel Ch2.
[0082]
Next, the second treatment in this embodiment will be described.
If the management server 2 can acquire two values of ESS-ID # A and ESS-ID # E when receiving the inquiry packet, both of these values are included in the response packet. I will do it. If the response packet includes a plurality of ESS-ID values, the access point device 1 indicates all these values in the response message.
[0083]
Thus, by receiving such an answer message, the wireless terminal device 3 can know the two values of ESS-ID # A and ESS-ID # E together. In the wireless terminal device 3, these values are sequentially selected as ESS-ID, and carrier sense is performed, so that even if the wireless channel Ch 4 having ESS-ID # A cannot be found, ESS-ID # E is set. It is possible that the wireless channel Ch2 that the user has is found and accessible by this wireless channel Ch2.
[0084]
However, when the management server 2 can acquire a plurality of ESS-ID values in the first and second embodiments, it is desirable to specify a recommended order for these values.
For example, the recommended order may be the following order.
(1) The ESS-ID of the wireless channel used by the company designated by the wireless terminal device 3.
(2) ESS-ID of the wireless channel used by the partner company.
However, when there are a plurality of wireless channels used by the same company, it is necessary to further define the recommended order. In the following, three methods will be exemplified.
[0085]
In the first method according to the present embodiment, the management server 2 periodically exchanges information with the access point device 1 to obtain information on the degree of congestion of wireless traffic. And the management server 2 selects in order from the radio channel which is not congested. However, even with the degree of congestion, since the maximum communication capacity of the radio itself varies depending on the radio frequency and method, selection is made in consideration of this point.
[0086]
In the second method in the present embodiment, the random number calculation is simply performed, and the selected radio channel is designated by the result of the random number value. For example, if two radio channels are selected, a method is possible in which a random number that takes a value between 0 and 1 is moved and a determination is made based on whether the output value is 0.5 or more.
[0087]
In the third method in the present embodiment, the management server 2 obtains in advance information about the mutual positional relationship of the wireless antennas 13 of the access point device 1. Then, the access point device 1 sends the identification information of the wireless channel, the wireless antenna 13 or the wireless interface 12 used for access by the wireless terminal device 3 to the management server 2 in the inquiry packet. Based on the information, the management server 2 preferentially selects a wireless channel having a service area close to the service area of the wireless channel that the wireless terminal device 3 is accessing from among a plurality of wireless channels that can be serviced. .
[0088]
(Second Embodiment)
The operation of the second embodiment of the wireless communication system configured as described above will be described below.
FIG. 8 is a sequence diagram of radio access in the second embodiment. FIG. 9 is a flowchart of the management server 2 in the second embodiment. In FIG. 8, the same event as in FIG. 6 and the same step in FIG. 9 as in FIG. 7 are denoted by the same reference numerals, and detailed description thereof is omitted.
[0089]
The second embodiment is based on the premise that the user of the wireless terminal device 3 already knows the ESS-ID of the wireless channel used by the already subscribed ISP or the like.
In this case, if the wireless terminal device 3 performs carrier sense, a wireless channel can be found. However, if carrier sensing is performed for all the wireless channels, the access point device 1 is far away. If you do not search for quite a long time, it may not be found, and it may take a long time before you can actually receive the service.
[0090]
Therefore, the second embodiment eliminates the need for complicated carrier sense.
The operation until the inquiry packet is sent to the management server 2 is the same as that in the first embodiment. Then, the management server 2 executes the process shown in FIG. 9 in response to the inquiry packet having arrived via the network 4.
[0091]
In the process of FIG. 9, the management server 2 performs the same processes as in the process of FIG. 7 in the first embodiment until step ST3. Then, after interpreting the contents of the inquiry packet in step ST3, the management server 2 acquires the radio channel information from the correspondence table 24 in step ST11. The radio channel information acquired here is a radio frequency band used by an ISP or the like described in the inquiry packet in an area near the wireless interface 12 that the wireless terminal device 3 has accessed for transmission of the inquiry message. And the information of the radio channel.
[0092]
Subsequently, in step ST12, the management server 2 confirms whether or not the acquisition of the wireless channel information has been successful. If successful, in step ST13, the management server 2 creates a reply packet indicating the acquired wireless channel information. If acquisition of the wireless channel information has failed, the management server 2 creates a reply packet indicating notification information for notifying failure in step ST7. In step ST13, the management server 2 also includes the identifier of the wireless interface 12 or the wireless antenna 13 and the identifier of the wireless terminal device 3 included in the inquiry packet in the reply packet.
[0093]
In step ST8, the management server 2 sends the response packet created in step ST13 or step ST7 to the network 4 toward the access point device 1 (E11 in FIG. 8).
[0094]
In the access point device 1, when the answer packet arrives via the network 4, the answer packet is fetched by the wired port 11 and passed to the control unit 14 via the switch unit 15. The control unit 14 interprets the content of the reply packet and extracts the radio channel information or notification information indicated in the reply packet. Then, the control unit 14 creates a reply message including the extracted wireless channel information or notification information, and transmits this reply message to the wireless terminal device 3. At this time, the wireless channel corresponding to the identifier of the wireless interface 12 or the wireless antenna 13 indicated in the reply packet is used, and the destination of the reply message is the identifier of the wireless terminal device 3 included in the reply packet. Therefore, a reply message is sent to the wireless terminal device 3 that has transmitted the inquiry message using the same wireless channel Ch1 to which the inquiry message is transmitted (E12 in FIG. 8).
[0095]
Thus, the wireless terminal device 3 can receive the reply message transmitted from the access point device 1 by waiting on the wireless channel used to transmit the inquiry message.
[0096]
When the wireless terminal device 3 receives the reply message, the wireless terminal device 3 confirms which of the wireless channel information and the notification information indicating failure is included. If the notification information indicating the failure is included, the wireless terminal device 3 has not been able to acquire the wireless channel information necessary for receiving the desired service, and therefore notifies the user accordingly. To do. Alternatively, carrier sense may be executed to find a radio channel.
[0097]
If the response message includes the wireless channel information, the wireless terminal device 3 can acquire the wireless frequency to be associated and the value of the wireless channel by analyzing the wireless channel information. Therefore, the wireless terminal device 3 performs carrier sense only on the wireless channel determined by this value, listens to the value of the ESS-ID broadcast on the wireless channel, sets it to a predetermined location of the terminal, and then An association request message including an appropriate ESS-ID value is sent to the access point apparatus 1. (E13 in FIG. 8).
[0098]
As described above, according to the second embodiment, even if the wireless terminal device 3 does not know the wireless channel to which the known ESS-ID is assigned, the name of the subscribed ISP, communication carrier, etc. The wireless channel to be used can be taught to the wireless terminal device 3 based on information indicating one service group. As a result, the wireless terminal device 3 does not need to perform carrier sense for a number of wireless channels, and can quickly perform association.
[0099]
By the way, as described above, since the radio channel can be appropriately designated to the radio terminal device 3 and the association can be performed using this radio channel, the second embodiment is operated in the following manner. This makes it possible to provide new convenient services.
[0100]
Here, a case will be described as an example where company B is serving both wireless channel Ch2 and wireless channel Ch4.
[0101]
When the inquiry packet arrives from the access point device 1, the management server 2 selects one from a plurality of existing radio channels. In the following, four methods are exemplified.
[0102]
In the first method according to the present embodiment, the management server 2 periodically exchanges information with the access point device 1 to obtain information on the degree of congestion of wireless traffic. And the management server 2 selects in order from the radio channel which is not congested. However, even with the degree of congestion, since the maximum communication capacity of the radio itself varies depending on the radio frequency and method, selection is made in consideration of this point.
[0103]
In the second method in the present embodiment, the random number calculation is simply performed, and the selected radio channel is designated by the result of the random number value. For example, if two radio channels are selected, a method is possible in which a random number that takes a value between 0 and 1 is moved and a determination is made based on whether the output value is 0.5 or more.
[0104]
In the third method in the present embodiment, the access point device 1 includes information on the radio frequency band accessed by the wireless terminal device 3 for transmission of the inquiry message in the inquiry packet. The management server 2 selects a radio channel from the radio frequency band accessed by the radio terminal device 3 as much as possible based on the above information.
[0105]
Hereinafter, an example of selecting from the wireless channels Ch2 and Ch4 when the wireless terminal device 3 has accessed in the 5.2 GHz band will be described in detail.
(1) When the radio channel Ch2 is in the 2.4 GHz band and the radio channel Ch4 is in the 5.2 GHz band, the radio channel Ch4 is selected.
(2) If both the radio channel Ch2 and the radio channel Ch4 are in the 5.2 GHz band, one of the radio channels is selected according to the procedure of the method 4 or the method 5 described above.
(3) Even when both the radio channel Ch2 and the radio channel Ch4 are in the 2.4 GHz band, one of the radio channels is selected according to the procedure of the method 4 or the method 5 described above.
[0106]
In the fourth method in the present embodiment, the management server 2 obtains in advance information about the mutual positional relationship of the wireless antennas 13 of the access point device 1. Then, the access point device 1 sends the identification information of the wireless channel, the wireless antenna 13 or the wireless interface 12 used for access by the wireless terminal device 3 to the management server 2 in the inquiry packet. Based on the information, the management server 2 preferentially selects a wireless channel having a service area close to the service area of the wireless channel to which the wireless terminal device 3 is accessing, from among a plurality of serviceable wireless channels. .
[0107]
However, in the fourth method, there is a risk of causing a traffic bias. Therefore, in combination with the first method, when the traffic bias is too large beyond a certain threshold, the wireless method does not depend on the area. It is also effective to reduce traffic bias by assigning channels.
[0108]
The management server 2 selects a radio channel by any method from the first method to the fourth method.
[0109]
However, one problem occurs here. That is, even when the radio channel selected as described above is used, there is a case where the radio terminal device 3 cannot perform carrier sense or cannot access.
[0110]
The following two causes can be considered as a cause of such a situation.
The first cause is that the radio terminal device 3 is not adapted to the designated radio frequency band. For example, this is the case when the wireless terminal device 3 can access only the 5.2 GHz band, but the 2.4 GHz band wireless channel is designated.
[0111]
The second cause is that access to the designated radio channel is not possible because the radio wave intensity in the radio terminal device 3 is weak. Even if the area is near, this is a case where it becomes a so-called “hidden terminal” due to the influence of an obstacle or the like.
[0112]
In the situation where the same service is provided by a plurality of radio channels in the same area as in the specific example here, the above-described problems can be dealt with by the following two measures.
[0113]
First, the first treatment in the present embodiment will be described.
[0114]
It is assumed that the wireless terminal device 3 determines that access through the notified wireless channel (specifically, for example, the wireless channel Ch4) is impossible. In this case, the wireless terminal device 3 transmits the inquiry message again. At this time, since there is a possibility that the wireless terminal device 3 is moving, the wireless channel to be accessed and the access point device 1 may be changed.
[0115]
At this time, the value “ANY” is described in the ESS-ID field of the inquiry message. It also includes the identifier of the radio channel that failed to access recently.
[0116]
The access point device 1 sends an inquiry packet to the management server 2 by the method already described. However, a wireless channel identifier as past failure information is also entered. The management server 2 newly acquires an appropriate radio channel identifier by comprehensively considering the identifier and failure information of the wireless terminal device 3 that has attempted access in the past and the current position of the wireless terminal device 3. If it is determined that the current location is the same as the area of the wireless channel Ch4, for example, information on the wireless channel Ch2 in the same area is returned to the wireless terminal device 3. If there is no other applicable radio channel, this is notified.
[0117]
Next, the second treatment in the present embodiment will be described.
[0118]
When the management server 2 receives the inquiry packet, the management server 2 includes all the wireless channel information related to all possible wireless channels (in this specific example, the wireless channel Ch2 and the wireless channel Ch4) in the reply packet. Since the wireless terminal device 3 can freely try to access by selecting from the plurality of wireless channels, even if the wireless channel Ch4 is unsuccessful, it is possible that the wireless terminal device 3 can be connected by the wireless channel Ch2.
[0119]
However, the management server 2 wants to specify the recommended order of connection when sending these pieces of information. As the order of recommendation, it is preferable to give priority by any of the above-mentioned four methods.
[0120]
(Third embodiment)
The operation in the third embodiment of the wireless communication system configured as described above will be described below.
FIG. 10 is a sequence diagram of wireless access in the third embodiment. FIG. 11 is a flowchart of the management server 2 in the third embodiment. 10, the same event as in FIG. 6 and the same step in FIG. 11 as in FIG. 7 are denoted by the same reference numerals, and detailed description thereof is omitted.
[0121]
In the third embodiment, the user of the wireless terminal device 3 tries to receive a service provided by an ISP or the like to which the user has already subscribed, but the user sets the ESS-ID of the wireless channel used for the service. The same situation as in the first embodiment, which is not known, is assumed. The third embodiment eliminates the need for complicated carrier sense as in the second embodiment.
[0122]
The operation until the inquiry packet is sent to the management server 2 is the same as that in the first embodiment. Then, the management server 2 executes the process shown in FIG. 11 in response to the inquiry packet having arrived via the network 4.
[0123]
In the process of FIG. 11, the management server 2 performs the process up to step ST3 in the same manner as the process of FIG. 7 in the first embodiment. Then, after interpreting the contents of the inquiry packet in step ST3, the management server 2 acquires the wireless channel information and the ESS-ID from the correspondence table 24 in step ST21. Acquisition of radio channel information can be performed in the same manner as in the second embodiment, and acquisition of ESS-ID can be performed in the same manner as in the first embodiment.
[0124]
Subsequently, in step ST22, the management server 2 confirms whether or not the acquisition of the radio channel information and the ESS-ID is successful. If successful, in step ST23, the response indicating the acquired radio channel information and the ESS-ID. Create a packet. If acquisition of the wireless channel information and the ESS-ID fails, the management server 2 creates a reply packet indicating notification information for notifying failure in step ST7. In step ST23, the management server 2 also includes the identifier of the wireless interface 12 or the wireless antenna 13 and the identifier of the wireless terminal device 3 included in the inquiry packet in the reply packet.
[0125]
In step ST8, the management server 2 sends the reply packet created in step ST23 or step ST7 to the network 4 toward the access point device 1 (E21 in FIG. 10).
[0126]
In the access point device 1, when the answer packet arrives via the network 4, the answer packet is fetched by the wired port 11 and passed to the control unit 14 via the switch unit 15. The control unit 14 interprets the content of the reply packet and extracts the radio channel information and ESS-ID or notification information indicated in the reply packet. Then, the control unit 14 creates a reply message including the extracted wireless channel information and ESS-ID or notification information, and transmits this reply message to the wireless terminal device 3. At this time, the wireless channel corresponding to the identifier of the wireless interface 12 or the wireless antenna 13 indicated in the reply packet is used, and the destination of the reply message is the identifier of the wireless terminal device 3 included in the reply packet. Therefore, a reply message is sent to the wireless terminal device 3 that has transmitted the inquiry message using the same wireless channel Ch1 to which the inquiry message is transmitted (E22 in FIG. 10).
[0127]
Thus, the wireless terminal device 3 can receive the reply message transmitted from the access point device 1 by waiting on the wireless channel used to transmit the inquiry message.
[0128]
When the wireless terminal device 3 receives the reply message, the wireless terminal device 3 confirms which of the wireless channel information, the ESS-ID, and the notification information indicating the failure is included. If the notification information indicating the failure is included, the wireless terminal device 3 could not acquire the wireless channel information and ESS-ID necessary for receiving the desired service. To the user.
[0129]
If the response message includes the wireless channel information and the ESS-ID, the wireless terminal device 3 can acquire the wireless frequency to be associated and the value of the wireless channel by analyzing the wireless channel information. Moreover, the value of ESS-ID for accessing the radio channel determined by this value can be acquired. Therefore, the wireless terminal device 3 performs carrier sense only on the above wireless channel, listens to the value of the ESS-ID broadcast on the wireless channel, sets it to a predetermined location of the terminal, and then An association request message including the acquired ESS-ID value is sent to the access point apparatus 1. (E23 in FIG. 10).
[0130]
As described above, according to the third embodiment, even if the wireless terminal device 3 does not know an appropriate ESS-ID, it refers to one service group such as the name of the subscribed ISP or communication carrier. Based on the information, an appropriate ESS-ID value can be taught to the wireless terminal device 3, thereby enabling appropriate association. In addition, since the wireless channel to which the ESS-ID is assigned, that is, the wireless channel to be used, can be taught to the wireless terminal device 3, the wireless terminal device 3 can perform carrier sense for a number of wireless channels. It is not necessary to do so, and it is possible to perform association quickly.
[0131]
By the way, since the combination of the radio frequency, the radio channel, and the ESS-ID can be appropriately designated to the radio terminal device 3 and the association can be performed under the conditions as described above, the third embodiment is described below. It becomes possible to provide a new convenient service by operating in such a form.
[0132]
Here, company C is using ESS-ID # CC for wireless channel Ch2 and ESS-ID # C for wireless channel Ch4, and company F is affiliated with company C. Will be described by taking as an example a case where the wireless channel Ch3 is serving using ESS-ID # F.
[0133]
Now, even if the wireless terminal device 3 tries to access the wireless channel specified as described above using the specified ESS-ID, the wireless terminal device 3 cannot perform carrier sense or may access it. It may not be possible.
[0134]
The following two causes can be considered as a cause of such a situation.
The first cause is that the radio terminal device 3 is not adapted to the designated radio frequency band. For example, this is the case when the wireless terminal device 3 can access only the 5.2 GHz band, but the 2.4 GHz band wireless channel is designated.
[0135]
The second cause is that access to the designated radio channel is not possible because the radio wave intensity in the radio terminal device 3 is weak. Even if the area is near, this is a case where it becomes a so-called “hidden terminal” due to the influence of an obstacle or the like.
[0136]
In the situation where the same service is provided by a plurality of radio channels in the same area as in the specific example here, the above-described problems can be dealt with by the following two measures.
[0137]
First, the first treatment in the present embodiment will be described.
[0138]
Assume that the wireless terminal device 3 determines that access through the designated wireless channel Ch4 is impossible. In this case, the wireless terminal device 3 transmits the inquiry message again. At this time, since the wireless terminal device 3 may be moving, the wireless channel and the access point device 1 used for transmitting the inquiry message may be changed. At this time, the value “ANY” is described in the ESS-ID field of the inquiry message. In the inquiry message, “ESS-ID # C” as the value of the ESS-ID and the identification information of the radio channel Ch4 are also described as information on the recent access failure.
[0139]
In the access point device 1, the inquiry packet created based on the inquiry message also includes information on the access failure.
[0140]
The management server 2 obtains an appropriate ESS-ID by comprehensively considering the identifier of the wireless terminal device 3 that has attempted access in the past, information on access failure, and the current position of the wireless terminal device 3.
[0141]
In the case of the above specific example, if the wireless terminal device 3 is not moving, the combination of the ESS-ID # CC of the company C and the wireless channel Ch2, or the ESS-ID # F of the company F and the wireless channel Ch3 Will get one of the combinations. Note that, in the above two combinations, it is generally preferable to preferentially obtain a combination related to company C with which the user of the wireless terminal device 3 has a contract.
[0142]
By receiving the reply message transmitted from the access point device 1 based on the reply packet, the wireless terminal device 3 can combine the ESS-ID # CC of company C with the wireless channel Ch2, or the ESS of company F. -You can know the combination with ID # F and radio channel Ch3. If a radio channel Ch2 having ESS-ID # CC or a radio channel Ch3 having ESS-ID # F can be found, the service C or F company is provided by using the radio channel Ch2 or radio channel Ch3. It becomes possible.
[0143]
Next, the second treatment in this embodiment will be described.
[0144]
The management server 2 acquires all possible combinations when receiving the inquiry packet. In the case of the specific example here, the combination of ESS-ID # CC and radio channel Ch2, the combination of ESS-ID # F and radio channel Ch2, and the combination of ESS-ID # C and radio channel Ch4. Get each combination. All of these combinations are included in the reply packet. If a plurality of combinations are included in the reply packet, the access point device 1 indicates all of these combinations in the reply message.
[0145]
Thus, by receiving such an answer message, the wireless terminal device 3 can collectively know a plurality of combinations of usable ESS-IDs and wireless channels. The wireless terminal device 3 can freely select one of these combinations and perform carrier sense, so even if ESS-ID # C is unsuccessful, the other two types of ESS -Connection may be possible depending on the combination of ID and wireless channel.
[0146]
However, when the management server 2 can acquire a plurality of combinations of ESS-IDs and radio channels in the fifth and sixth embodiments, it is desirable to specify a recommended order for these combinations.
[0147]
The following four methods can be considered for determining the recommended order.
In the first method according to the present embodiment, the management server 2 periodically exchanges information with the access point device 1 to obtain information on the degree of congestion of wireless traffic. And the management server 2 selects in order from the combination containing the radio channel which is not crowded. However, even with the degree of congestion, since the maximum communication capacity of the radio itself varies depending on the radio frequency and method, selection is made in consideration of this point.
[0148]
In the second method in the present embodiment, the management server 2 performs a random number calculation very simply and designates a combination including the selected radio channel based on the result of the random number value. For example, in the case of selection from two combinations, a random number that takes a value between 0 and 1 is moved, and the determination is made based on whether the output value is 0.5 or more.
[0149]
In the third method in the present embodiment, the access point device 1 includes information on the radio frequency band accessed by the wireless terminal device 3 for transmission of the inquiry message in the inquiry packet. Then, the management server 2 preferentially selects a radio channel in the radio frequency band accessed by the radio terminal device 3 based on the above information.
[0150]
Hereinafter, an example of selecting from the wireless channels Ch2 and Ch4 when the wireless terminal device 3 has accessed in the 5.2 GHz band will be described in detail.
(1) When the radio channel Ch2 is in the 2.4 GHz band and the radio channel Ch4 is in the 5.2 GHz band, the radio channel Ch4 is prioritized.
(2) When both the radio channel Ch2 and the radio channel Ch4 are in the 5.2 GHz band, priority is given to either radio channel according to the procedure of the first method or the second method.
(3) Even when both the radio channel Ch2 and the radio channel Ch4 are in the 2.4 GHz band, priority is given to one of the radio channels according to the procedure of the first method or the second method.
[0151]
In the fourth method in the present embodiment, the management server 2 obtains in advance information about the mutual positional relationship of the wireless antennas 13 of the access point device 1. Then, the access point device 1 sends the identification information of the wireless channel, the wireless antenna 13 or the wireless interface 12 used for access by the wireless terminal device 3 to the management server 2 in the inquiry packet. Based on the information, the management server 2 preferentially selects a combination having a service area close to the service area of the wireless channel that the wireless terminal device 3 is accessing from among a plurality of combinations that can be serviced. . However, since this method 11 may cause a traffic bias, it does not depend on the area when the traffic bias exceeds a certain threshold in combination with the method 8. It is desirable to reduce traffic bias by a method of assigning a radio channel.
[0152]
By the way, when prioritization is performed in this way, it is convenient to provide a sub-table for prioritization in addition to the correspondence table 24 in the management server 2.
For example, in the case of the first method, it is conceivable to prepare a table of radio traffic congestion degree information as a sub table. As the simplest and relatively effective congestion degree information, for example, a value obtained by subtracting the average traffic (bit rate) for a certain time from the maximum traffic capacity of the radio can be used. At this time, the greater the congestion degree information value, the more “not crowded” can be determined.
In the case of the second method described above, since the random number calculation is performed, a sub table such as a simple random table may be used.
In the case of the third method, a sub table is prepared for the first method or the second method. In the case of the third method, the information on the frequency band to which the wireless terminal device 3 is attempting to access is effective for prioritization, but this information is not information that will be tabulated again. .
In the case of the fourth method, a table regarding the wireless antenna 13 and the wireless channel of the access point device 1 and the degree of adjacency thereof can be used as a sub table.
[0153]
Each of the above embodiments can be modified in various ways as follows.
(First modification)
For example, the function of the management server 2 in each of the above embodiments can be provided in the access point device.
FIG. 12 is a block diagram showing a configuration example of an access point device having the function of the management server 2. In FIG. 12, the same parts as those in FIG. 2 are denoted by the same reference numerals, and detailed description thereof is omitted.
[0154]
The access point device 5 illustrated in FIG. 12 includes a wired port 11, a wireless interface 12, a wireless antenna 13, a switch unit 15, and a control unit 51. That is, the access point device 5 includes a control unit 51 instead of the control unit 14 in the access point device 1.
[0155]
The control unit 51 includes a frame reception unit 511, an ESS-ID confirmation unit 512, a reception frame interpretation unit 513, a correspondence table 514, a terminal message creation unit 515, and a frame generation unit 516.
[0156]
The signal extracted by the wireless reception unit 122 of the wireless interface 12 is input to the frame reception unit 511 of the control unit 51 via the switch unit 15.
[0157]
The frame reception unit 511 extracts a packet after synthesizing the signal frame output from the wireless reception unit 122. The frame receiving unit 511 confirms the type of the extracted packet. The frame receiving unit 511 gives a packet for normal data communication to the packet routing unit 111 via the switch unit 15. When the packet is the first-level association request message and the value of the ESS-ID is “ANY”, the frame reception unit 511 sends the contents of this message to the ESS-ID confirmation unit 512. The ESS-ID confirmation unit 512 classifies the received message into an inquiry message to be described later and a message that is not, and analyzes the contents of the message only for the former. Then, the ESS-ID confirmation unit 512 passes the analyzed content to the received frame interpretation unit 513.
[0158]
The received frame interpretation unit 513 analyzes the passed information, and acquires from the correspondence table 514 information such as the radio channel belonging to the service group indicated in the inquiry packet and the ESS-ID assigned to the radio channel. The correspondence table 514 conforms to the correspondence table 24 in the above embodiment.
[0159]
The reception frame interpretation unit 513 passes the information acquired from the correspondence table 514 to the terminal message creation unit 515. The terminal message creation unit 515 creates a reply message indicating the information passed from the received frame interpretation unit 513, and passes this reply message to the frame generation unit 516. The frame generation unit 516 generates a signal obtained by framing the packet delivered from the packet routing unit 111 and the reply message delivered from the terminal message creation unit 515, and transmits this signal via the switch unit 15 via the wireless interface 12. To part 123.
[0160]
Thus, by using such an access point device 5, the wireless communication system of the present invention can be realized without using the management server 2.
[0161]
The access point device 5 further has a function of receiving the inquiry packet in the embodiment that the management server 2 has, a function of creating a reply packet according to the inquiry packet, and the reply packet to another access point. By providing the function of sending to the device, it is possible to construct a wireless communication system by combining this access point device 5 and the access point device 1 in the above embodiment.
[0162]
(Second modification)
FIG. 13 is an overall configuration diagram of a radio communication system according to a second modification of each of the embodiments. 13, the same parts as those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof is omitted.
[0163]
As shown in FIG. 13, a plurality of access point devices 6 may be provided, and a plurality of wireless interfaces 12 and a plurality of wireless antennas 13 may be distributed and arranged in the plurality of access point devices 6 described above. In this case, a plurality of control units 14 are also provided and distributed in each access point device 6. One wired port 11 is also provided for each access point device 6.
Even with such a configuration, it is possible to provide a wireless communication service similar to that of the above-described embodiment.
[0164]
(Other variations)
It is also possible to implement a combination of the first modification and the second modification.
Even when a plurality of wireless interfaces 12 are mounted as in the access point device 1 of each embodiment, a dedicated control unit 14 is provided for each wireless interface 12 as in the second embodiment. Is also possible.
[0165]
The wireless communication system of the present invention can be applied not only in a spot area but also in an environment such as an office or a home. For example, in an environment where there are a plurality of departments in an office, a server is installed for each department, and a wireless channel is also assigned to each department, the wireless terminal device 3 uses the inquiry message as a service group as the service group name. By describing (for example, “Research and Development Department”, etc.), it becomes possible to distribute the radio channel used by each user according to the department to which the user belongs. This can be used to isolate information from the adjacent departments in the office, and there is also an advantage that the wireless terminal device 3 does not have to receive traffic of other three kinds of unnecessary departments.
[0166]
As can be seen from the above modification, any information can be used as the information for determining the service group. For example, when a plurality of ISPs cooperate with each other to form a roaming group, a name or identifier for identifying the roaming group can be used as a service group. Alternatively, it is possible to use a service group in a form representing the nature of a service such as “Internet connection”.
[0167]
As the identifier for accessing the wireless channel, other planned information such as SSID can be applied, or an identifier uniquely defined outside the standard can be applied.
[0168]
In the correspondence table 24, the description of the ID number entry may be devised so that a combination of ID numbers can be displayed for those having a roaming alliance.
[0169]
Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. In addition, various inventions can be formed by appropriately combining a plurality of components disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined.
[0170]
【The invention's effect】
It is possible to efficiently provide communication services using a plurality of radio channels in overlapping areas.
[Brief description of the drawings]
FIG. 1 is an overall configuration diagram of a wireless communication system according to an embodiment of the present invention.
FIG. 2 is a block diagram showing a detailed configuration of the access point device 1 in FIG.
FIG. 3 is a block diagram showing the configuration of the management server 2 in FIG.
4 is a view showing an example of information described in a correspondence table 24. FIG.
5 is a block diagram showing a configuration of a wireless terminal device 3 in FIG.
FIG. 6 is a sequence diagram of wireless access in the first embodiment.
FIG. 7 is a flowchart in the first embodiment of the management server 2 in FIG. 1;
FIG. 8 is a sequence diagram of radio access in the second embodiment.
FIG. 9 is a flowchart in the second embodiment of the management server 2 in FIG. 1;
FIG. 10 is a sequence diagram of wireless access in the third embodiment.
FIG. 11 is a flowchart in the third embodiment of the management server 2 in FIG. 1;
FIG. 12 is a block diagram showing a configuration example of an access point apparatus having the function of the management server 2;
FIG. 13 is an overall configuration diagram of a wireless communication system according to a second modified example related to the first to third embodiments.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1,5,6 ... Access point apparatus, 2 ... Management server, 3 ... Wireless terminal device, 4 ... Network, 11 ... Wired port, 12 ... Wireless interface, 13, 31 ... Wireless antenna, 14, 51 ... Control part, 15 ... Switch unit, 21 ... Wired port, 22 ... Packet reception unit, 23 ... Reception packet interpretation unit, 24,514 ... Correspondence table, 25 ... Transmission packet creation unit, 26 ... Packet transmission unit, 32,121 ... Antenna duplexer, 33, 122 ... wireless reception unit, 34, 141, 511 ... frame reception unit, 35 ... application reception unit, 36 ... screen display unit, 37 ... application transmission unit, 38 ... subscribing carrier ID / subscription ISP ID management unit, 39 ... In-house group ID management unit, 40 ... selection unit, 41 ... ESS-ID setting unit, 42, 146, 516 ... frame generation unit, 43, 123 ... wireless transmission unit, 44 , 124 ... Frequency / channel setting unit, 111 ... Packet routing unit, 142, 512 ... ESS-ID confirmation unit, 143 ... Management server packet creation unit, 144 ... Reply packet interpretation unit, 145, 515 ... Terminal message creation unit 513: Received frame interpretation unit.

Claims (10)

In a wireless communication system including a wireless terminal device and a communication network that allows the wireless terminal device to communicate using a plurality of wireless channels each belonging to one of a plurality of service groups and assigned an identifier,
First transmission means provided in the wireless terminal device, for transmitting inquiry information indicating one of the plurality of service groups using the wireless channel;
First receiving means provided in the communication network for receiving the inquiry information;
Selecting means for selecting the radio channel belonging to the service group provided in the communication network and indicated in the received inquiry information;
Generating means for generating reply information indicating at least one of the selected radio channel and the selected identifier assigned to the selected radio channel, provided in the communication network;
Second transmission means provided in the communication network, for transmitting the answer information to the wireless terminal device using the wireless channel used for transmitting the inquiry information;
A wireless communication system, comprising: a second receiving unit that is provided in the wireless terminal device and receives the answer information transmitted by the second transmitting unit. The communication network includes an access point device including the first reception unit and the second transmission unit, and a management device including the selection unit and the generation unit.
A third transmission unit provided in the access point device, for transmitting the inquiry information received by the first reception unit to the management device;
A third receiving means provided in the management device for receiving the inquiry information transmitted by the third transmitting means;
A fourth transmission unit provided in the management device, for transmitting the response information generated by the generation unit to the access point device;
The wireless communication system according to claim 1, further comprising a fourth receiving unit that is provided in the access point device and receives the response information transmitted by the fourth transmitting unit. The wireless communication system comprising: a wireless terminal device; and a communication network that allows the wireless terminal device to communicate using a plurality of wireless channels each belonging to any of a plurality of service groups and assigned an identifier. An access point device that is provided in a communication network together with a management device that manages at least one of correspondence between the service group and the wireless channel and correspondence between the wireless channel and the identifier, and performs wireless communication with the wireless terminal device In
First receiving means for receiving inquiry information transmitted from the wireless terminal device and indicating one of the plurality of service groups;
First transmission means for transmitting the received inquiry information to the management device;
Second receiving means for receiving response information transmitted from the management device based on the transmitted inquiry information;
An access point comprising: second transmission means for transmitting the response information received by the second reception means to the wireless terminal device using the wireless channel used for transmitting the inquiry information. apparatus. The wireless communication system comprising: a wireless terminal device; and a communication network that allows the wireless terminal device to communicate using a plurality of wireless channels each belonging to any of a plurality of service groups and assigned an identifier. In a management device provided in a communication network together with an access point device that performs wireless communication with the wireless terminal device, and manages at least one of the correspondence between the service group and the wireless channel and the correspondence between the wireless channel and the identifier ,
Receiving means for indicating one of the plurality of service groups and receiving inquiry information transmitted from the access point device;
Selecting means for selecting the radio channel belonging to the service group indicated in the received inquiry information;
Generating means for generating response information indicating at least one of the selected radio channel and the identifier assigned to the selected radio channel;
A management apparatus comprising: a transmission unit configured to transmit the answer information to the access point apparatus. The wireless communication system comprising: a wireless terminal device; and a communication network that allows the wireless terminal device to communicate using a plurality of wireless channels each belonging to any of a plurality of service groups and assigned an identifier. A management device provided in a communication network together with an access point device that performs wireless communication with the wireless terminal device, and manages at least one of a correspondence between the service group and the wireless channel and a correspondence between the wireless channel and the identifier A computer with
Receiving means for indicating one of the plurality of service groups and receiving inquiry information transmitted from the access point device;
Selecting means for selecting the radio channel belonging to the service group indicated in the received inquiry information;
Generating means for generating response information indicating at least one of the selected radio channel and the identifier assigned to the selected radio channel;
A program that causes the response information to function as a transmission unit that transmits to the access point device. The communication network includes an access point device,
The access point device is
Receiving means for receiving inquiry information transmitted from the wireless terminal device and indicating one of the plurality of service groups;
Selecting means for selecting the radio channel belonging to the service group indicated in the received inquiry information;
Generating means for generating response information indicating at least one of the selected radio channel and the identifier assigned to the selected radio channel;
The wireless communication system according to claim 1, further comprising: a transmission unit configured to transmit the answer information to the wireless terminal device using the wireless channel used for transmitting the inquiry information. A wireless communication system comprising: a wireless terminal device; and a communication network that allows the wireless terminal device to communicate using a plurality of wireless channels each belonging to one of a plurality of service groups and assigned with an identifier. In the access point device used,
Receiving means for receiving inquiry information transmitted from the wireless terminal device and indicating one of the plurality of service groups;
Selecting means for selecting the radio channel belonging to the service group indicated in the received inquiry information;
Generating means for generating response information indicating at least one of the selected radio channel and the identifier assigned to the selected radio channel;
An access point device comprising: a transmission unit configured to transmit the answer information to the wireless terminal device using the wireless channel used for transmitting the inquiry information. The wireless terminal device used in a wireless communication system including a communication network that allows a wireless terminal device to communicate using a plurality of wireless channels each belonging to any of a plurality of service groups and assigned an identifier. In
First transmission means for transmitting inquiry information indicating one of the plurality of service groups using the wireless channel;
Reply information indicating at least one of the wireless channel belonging to the service group indicated in the inquiry information and the identifier assigned to the wireless channel is used for transmitting the inquiry information from the communication network. wireless terminal and wherein through a radio channel by comprising a receiving means for receiving. The answer information shows only the identifier of the wireless channel and the identifier,
9. The wireless terminal device according to claim 8, further comprising search means for searching for a wireless channel to which the identifier indicated in the received answer information is assigned. Wireless communication in a wireless communication system including a wireless terminal device and a communication network that allows the wireless terminal device to communicate using a plurality of wireless channels each belonging to any of a plurality of service groups and assigned an identifier In the communication method,
The wireless terminal device transmits inquiry information indicating one of the plurality of service groups using the wireless channel,
Receiving the inquiry information in the communication network;
In the communication network, select the radio channel belonging to the service group indicated in the received inquiry information,
Generating response information indicating at least one of the selected radio channel and the identifier assigned to the selected radio channel in the communication network;
In the communication network, the response information is transmitted to the wireless terminal device using the wireless channel used for transmission of the inquiry information,
The wireless communication method, wherein the wireless terminal device receives the answer information transmitted by the second transmission means.

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