JP5693350B2 - Communication device, control method, and program - Google Patents

Description

  The present invention relates to a communication device and a program. More specifically, the present invention relates to a communication apparatus that establishes communication with another communication apparatus using a communication parameter, and a program.

  In wireless communication represented by a wireless LAN compliant with the IEEE 802.11 standard series, there are many setting items that must be set before use. For example, as setting items, there are communication parameters necessary for performing wireless communication such as an SSID (Service Set IDentifier) as a network identifier, an encryption method, an encryption key, an authentication method, and an authentication key. These are very complicated for the user to set manually.

  Therefore, various parameter manufacturers have proposed communication parameter automatic setting methods for easily setting communication parameters in wireless devices. In these communication parameter automatic setting methods, communication parameters are automatically provided from one device to the other device according to a procedure and a message determined in advance between connected devices, and communication parameters are automatically set.

  Non-Patent Document 1 describes an example of a communication parameter automatic setting method in wireless LAN infrastructure mode communication. In the method described in Non-Patent Document 1, a process of specifying whether or not a device selected by the user of the counterpart device is performed based on information (PIN code) input to the counterpart device. This is called a PIN code system. Further, Non-Patent Document 1 describes a push button method that is a method that does not perform processing for specifying whether or not the device is a device selected by the user of the counterpart device. This is called the PBC method.

  In this way, by using the communication parameter automatic setting method, the user can automatically set the communication parameters with a simple operation.

Wi-Fi CERTIFIED (TM) for Wi-Fi Protected Setup: Easing the User Experience for Home and Small Office Wi-Fi (R) Networks, http: // www. wi-fi. org / wifi-protected-setup

  Here, consider a case where a wireless network is controlled by a wireless LAN access point (hereinafter referred to as a “base station”). The wireless network is composed of this base station and a station (hereinafter referred to as “wireless terminal”) that exists in the radio wave reach of the base station and is connected to the base station via a wireless LAN. Furthermore, the communication parameter automatic setting method is applied to the connection by the wireless LAN, and the base station and the plurality of wireless terminals share the communication parameter by the communication parameter automatic setting method.

  In this wireless network, a user of a certain wireless terminal or a network administrator can change the communication parameters of the base station. However, when the communication parameter is changed, the communication parameter of the own terminal does not match the communication parameter of the base station in other wireless terminals that do not know the communication parameter. As a result, the user of the other wireless terminal cannot establish a wireless LAN connection with the base station and cannot participate in the wireless network. In this case, the user of the wireless terminal finds the cause of the inability to connect to the wireless network, but this has the problem that it takes time and is complicated.

  An object of this invention is to provide the technique which solves this subject. That is, an object of the present invention is to provide a communication device and a program for detecting a reason why wireless connection cannot be maintained when a wireless connection is requested and the connection fails.

In order to achieve the above object, the communication device of the present invention requests a wireless connection using the communication parameter , sharing means for sharing a communication parameter for wireless connection with another communication device with the other communication device. and request means, if it fails to wirelessly connect to the requesting means requests, determining means for determining whether or not a request by said request means is made to the other communication apparatus, the determination result by said determining means depending on has, and a notification control means for notifying that the setting of the other communication apparatus is changed.

According to the present invention, when a communication parameter is changed and the communication device can not be wirelessly connected to another communication device , control is performed so that the communication terminal itself notifies the cause of the connection failure, thereby improving the user-friendliness. .

1 is a system configuration diagram according to an embodiment. FIG. 2 is a functional block diagram of the printer 101 according to the embodiment. The sequence diagram concerning an embodiment. 5 is a flowchart executed by the printer 101 according to the embodiment. FIG. 3 is a sequence diagram between the printer 101 and the base station 103 according to the first embodiment. FIG. 9 is a sequence diagram between the printer 101 and the base station 103 according to the second embodiment. FIG. 10 is a sequence diagram between the printer 101 and the base station 103 according to the third embodiment. FIG. 10 is a sequence diagram between the printer 101 and the base station 103 according to the fourth embodiment. FIG. 10 is a functional block diagram of a printer 101 according to a fourth embodiment.

<< Embodiment 1 >>
(System configuration)
Embodiments according to the present invention will be described below with reference to the accompanying drawings. In the following, an example using a wireless LAN system in conformity with the IEEE 802.11 standard will be described, but the communication form is not necessarily limited to this.

  FIG. 1 is a configuration example of a wireless LAN system in the present embodiment. The base station 103 operates in accordance with an access point function corresponding to the IEEE 802.11 standard. Hereinafter, a case will be described in which a printer 101 and a PC 102 including a communication apparatus having a wireless LAN communication function request connection to the base station 103 and participate in a wireless network formed by the base station 103.

(Functional configuration)
A block diagram of a communication apparatus in the printer 101 is shown in FIG. First, the configuration of the printer 101 will be described. FIG. 2 is a functional block diagram of the printer 101 in this embodiment.

  The printer function unit 201 is a block that processes functions such as print processing. A detailed description of the function is not directly related to the description of the present embodiment, and is omitted here. The power supply unit 202 supplies power to functions necessary for the printer 101 to operate, such as the printer function unit 201 and the wireless communication function unit 204. The communication parameter automatic setting function unit 203 automatically sets communication parameters necessary for wireless communication such as an SSID as a network identifier, an encryption method, an encryption key, an authentication method, and an authentication key. The wireless communication function unit 204 is a block for functioning as a wireless terminal in accordance with the IEEE 802.11 standard. Specifically, the base station 103 is searched, wireless connection processing to the base station 103 is performed, and wireless communication with other wireless communication devices via the base station 103 is performed.

  The display processing unit 205 is a block that controls display contents for the user and displays the information as information on an LCD (Liquid Crystal Display) or LED (Light Emitting Diode). Operations such as settings related to the wireless function are performed via the operation unit 206. The operation unit 206 also includes a setting button for giving a trigger for starting the processing of the communication parameter automatic setting method. That is, in the printer 101, the display processing unit 205 and the operation unit 206 serve as a wireless function user interface (I / F).

  The CPU 207 is a processor that executes a program for controlling printing processing, wireless communication processing, and the like of the printer 101. A program executed by the CPU 207 is stored in a storage unit 208 configured by a RAM, a flash ROM, or the like. Communication parameters for wireless communication are also stored in the storage unit 208. Data processed by the CPU 207 is also written to and read from the storage unit 208.

  The wireless connection failure cause determination unit 209 investigates the cause of the wireless connection failure when the wireless connection fails. Specific operations will be described later in the description of S417 in FIG. 3 and related descriptions. And it notifies to a user via the display process part 205 as needed. Further, the communication parameter is automatically updated, and the wireless connection is reset according to the cause.

  The PC 102 is also realized with the same configuration as the printer 101. However, the PC 102 includes a function unit for processing functions specific to the PC 102 instead of the printer function unit 201 in the printer 101.

  In the above, the component apparatus of the system of FIG. 1 was demonstrated. In the system of FIG. 1, the printer 101 executes connection setting to the base station 103 using the communication parameter automatic setting method. When the connection with the base station 103 is successful, the printer 101 can participate in the wireless network formed by the base station 103. When the connection to the base station 103 is successful, the printer 101 stores the communication parameters in the storage unit 208 as connection information. The same applies to the PC 102.

  Note that there is no essential difference between the connection information and the communication parameters. However, in the following, the information stored in the printer 101 and the PC 102 and the information used by the base station are distinguished, and the former is used as connection information and the latter as communication parameters.

  As described above, after the printer 101 joins the network, for example, when the communication parameter of the base station 103 is changed by the user of the PC 102, the printer 101 can connect to the base station 103 using the stored connection information. Disappear. This is because the communication parameters used by the base station 103 and the connection information stored in the printer 101 are different.

  One of the purposes of the configuration according to the present embodiment is to cause the printer 101 to detect that the communication parameter of the base station 103 has been changed in such a case. In addition, by notifying the user of the printer 101 that the communication parameter has been detected, the reason why the printer 101 cannot connect to the base station 103 is clearly indicated to the user. Furthermore, based on the detection that the communication parameter has been changed, the printer 101 is caused to update the connection information with the base station 103 to establish communication.

  For this purpose, the printer 101 of the present embodiment is, for example, a first unique to the communication apparatus of the other party to be connected with the connection information (hereinafter referred to as “partner apparatus”; in this case, the base station 103). The identification information is stored in the storage unit 208 together with the above connection information. Then, the printer 101 tries to connect using the stored connection information. When the connection fails, the printer 101 acquires second identification information unique to the counterpart device from the counterpart device. Subsequently, the printer 101 compares the first identification information with the second identification information, and if they match, the other party that has been connected to the other party device with the stored connection information is the same, and the other party It detects that the device has changed the communication parameter. When the printer 101 detects a change in the communication parameter, the printer 101 notifies the user accordingly. Further, when the printer 101 detects a change in the communication parameter, the printer 101 updates the connection information stored in the storage unit 208 with the changed communication parameter to enable reconnection.

(Operation flow)
A specific operation will be described with reference to a sequence diagram between the printer 101, the PC 102, and the base station 103, and an operation flowchart of the printer 101. A sequence diagram is shown in FIGS. 3 and 5, and an operation flowchart of the printer 101 is shown in FIG. Hereinafter, the operation of the printer 101 will be described with reference to FIG. 4, but the PC 102 may perform the same operation. That is, after a user other than the PC 102 changes the communication parameter of the base station 103, the PC 102 may detect the cause of the connection failure using the operation of FIG.

  The base station 103 constructs a network conforming to the IEEE 802.11 standard, and starts sending a beacon (S401). Note that “abc” is used as the SSID as the network identifier. Each printer 101 executes the communication parameter automatic setting method and acquires communication parameters from the base station 103 (S402).

  Here, the printer 101 causes the storage unit 208 to store the acquired communication parameters as connection information. The communication parameters acquired here are communication parameters necessary for performing wireless communication such as SSID, encryption method, encryption key, authentication method, and authentication key. The printer 101 also acquires a communication parameter called “BSSID” (Basic Service Set IDentifier) as the first identification information of the base station 103 and stores it in the storage unit 208. At this time, the printer 101 may include the first identification information in the connection information and store it in the storage unit 208, or may store the connection information and the first identification information separately in association with each other. . The BSSID normally uses a MAC address of a wireless LAN access point. That is, the BSSID is a unique value assigned to the communication device so as not to overlap with other devices, and the first identification information is identification information unique to the base station 103.

  The printer 101 performs wireless connection using the acquired communication parameter (S404). Here, for example, immediately after the execution of the communication parameter automatic setting method, the printer 101 performs wireless connection using the acquired communication parameter, and stores the acquired communication parameter as connection information when the wireless connection is successful. It may be. On the other hand, if the connection fails at this time, it may be determined that the connection setting by the communication parameter automatic setting method is incomplete, the acquired communication parameter may be deleted, and the connection setting may be executed again. As a result, the storage unit 208 can be used efficiently.

  On the other hand, the PC 102 also performs wireless connection, for example, in the same manner as the printer 101 (S403, S405). Through these steps, for example, the image data in the PC 102 can be wirelessly transferred to the printer 101 via the base station 103 and printed (S406).

  Here, for example, after the printing process is completed, the wireless connection is canceled (S410) by turning off the power of the printer 101 and the PC 102 (S407, S408). Then, after canceling the wireless connection, the user of the PC 102 changes the “SSID” of the base station 103 from “abc” to “123” (S411). Whether or not other communication parameters are changed does not matter here. Thereafter, the user of the PC 102 turns on the PC 102 (S412). Here, the user of the PC 102 knows that the base station 103 has changed the communication parameter. Therefore, the user of the PC 102 causes the PC 102 to execute the communication parameter automatic setting method (S413). Then, the PC 102 acquires communication parameters from the base station 103 and stores the communication parameters in the storage unit 208 as connection information. The PC 102 performs wireless connection using the connection information (S414).

  The user of the PC 102 can also operate the PC 102 as a communication parameter providing device of the base station 103 and change the communication parameters of the base station 103 via the PC 102. In this case, the PC 102 can hold connection information corresponding to the changed communication parameter without executing the communication parameter automatic setting method, and can establish a wireless connection using the held connection information.

  In the process so far, the PC 102 is wirelessly connected to the base station 103, and no problem appears. However, in this situation, the SSID used by the printer 101 and the SSID used by the base station 103 are different. Further, the user of the printer 101 may not know that the communication parameter of the base station 103 has been changed. For this reason, if the user of the printer 101 turns on the power of the printer 101 (S415), the wireless connection cannot be established even if the wireless connection with the base station 103 is executed unless the communication parameter automatic setting method is executed again. (S416).

  Details regarding the state in which this connection fails will be described with reference to the sequence diagram of FIG. The printer 101 stores connection information to the base station 103 by executing the communication parameter automatic setting method (S402). For this reason, the printer 101 tries to connect to the base station 103 using this connection information (S416, S602). The printer 101 stores the SSID as “abc” as connection information to the base station 103 (S601).

  In order to connect to the base station 103, the printer 101 sends a search request for searching for a network, and starts detecting a network whose SSID is “abc” (S602). Upon receiving the search request, the base station 103 responds by including “123”, which is the SSID of the network constructed by itself, in the search response (S603). However, the printer 101 is waiting for a search response including “abc” as the SSID. As a result, the printer 101 cannot receive the search response including “abc” as the SSID and cannot detect the base station 103. Accordingly, the printer 101 fails in wireless connection (S604, S416).

  At this point, the printer 101 does not know what caused the connection failure. That is, the printer 101 does not know whether the base station 103 does not exist, whether the communication parameter has been changed, or whether the connection cannot be made due to another factor. For this reason, the printer 101 investigates the cause of the wireless connection failure (S417).

  The connection failure cause investigation process will be described with reference to the flowchart of FIG. The printer 101 determines whether a search response has been received in the previous connection attempt (S416) (S501). If the printer 101 cannot receive the search response (No in S501), it sends a search request again in another frequency band that it can use (S509, S510). If the search response cannot be received in all frequency bands that can be used by itself (Yes in S509), the printer 101 determines that the base station 103 does not exist in the vicinity of the printer 101 (S511), and notifies the display processing unit 205 to that effect. It is displayed (S512). Here, S509 and S510 can be omitted. For example, if the printer 101 supports only a single frequency band, S511 is immediately executed. Note that the operation example of S509 and S510 will be described in detail in the fourth embodiment.

  On the other hand, when the printer 101 receives a search response in the previous connection attempt (S416) (Yes in S501), the printer 101 uses the connection information stored in the printer 101 as the communication parameter included in the search response. Compare (S502). As a result of the comparison, if the communication parameter matches the stored connection information (Yes in S502), the printer 101 finds that the base station 103 is found and the communication parameter is not changed. Therefore, the printer 101 determines that the cause of the connection failure is not a communication parameter change (S507), and displays that fact on the display processing unit 205 (S508).

  On the other hand, as a result of comparing the communication parameters included in the search response with the identification information, if even part of them does not match (S502), the printer 101 acquires the BSSID as the second identification information from the search response. As described above, the BSSID is a value unique to the communication device and is included in the search response. Therefore, the printer 101 compares the BSSID (first identification information) stored in the printer 101 with the BSSID (second identification information) included in the search response, so that the base station 103 that has established communication is activated. It is confirmed whether there is (S503).

  If the first identification information matches the second identification information, the printer 101 can determine that the base station 103 that is the connection destination based on the stored connection information is the same as the communication device that transmitted the search response. (Yes in S503). As a result, since the printer 101 can detect that the base station 103 has changed the communication parameter (S504), the printer 101 subsequently shifts to communication parameter automatic setting (S505). Then, in order to execute the communication parameter automatic setting method, the printer 101 displays on the display processing unit 205 that the base station 103 side also needs to shift to the communication parameter automatic setting execution state (S506). Note that S505 and S506 can be omitted. In this case, for example, the display processing unit 205 displays that the connection could not be made due to the change of the communication parameter, and the process is terminated.

  On the other hand, if the first identification information and the second identification information do not match (No in S503), the printer 101 determines that the communication device that transmitted the search response is not the base station 103. Note that the printer 101 may store a plurality of pieces of connection information related to communications established in the past in the storage unit 208. In this case, the printer 101 compares the second identification information with the first identification information corresponding to each of the connection information stored in the storage unit 208. If all the connection information stored in the storage unit 208 does not match the first identification information and the second identification information, the printer 101 determines that the base station 103 does not exist (S511). If the printer 101 determines that there is no base station, the printer 101 displays that fact on the display processing unit 205 (S512).

  In this embodiment, the base station 103 transmits a search response to the printer 101 in response to receiving the search request (S602) of the printer 101 (S603). For this reason, the printer 101 receives the search response (Yes in S501), and further, since the search response includes an SSID different from the SSID stored in the printer 101, the communication parameters do not match (No in S502). ). However, the search response is a signal transmitted by the base station 103. For this reason, the first identification information and the second identification information match (Yes in S503). Thereby, the printer 101 can detect that the base station 103 exists and the SSID, which is one of the communication parameters, has been changed in the base station 103 (S504). Thereafter, the printer 101 automatically transitions to the execution preparation state of the communication parameter automatic setting method (S505). Note that an instruction to execute the communication parameter automatic setting method may be notified to the user via the display processing unit 205, and the instruction may be executed by the user. In this case, the printer 101 is shifted to the execution preparation state of the communication parameter automatic setting method by the user's execution operation.

  Further, the base station 103 notifies the user that the communication parameter automatic setting method should be executed via the display processing unit 205 (S506). Specifically, a display such as “The communication parameter of the base station 103 has been changed. Please execute communication parameter automatic setting again” is desirable. Or, “by performing automatic communication parameter setting of the base station 103, wireless connection becomes possible.” Desirable display content is that the user can notify the base station 103 that the communication parameter automatic setting method is executed again so that the wireless connection recovery processing is executed. Alternatively, a notification that is defined in the instruction manual such as a notification by sound such as a buzzer sound, a blinking pattern of an LED, etc. may be used.

  After performing the connection failure cause investigation, the communication parameter automatic setting method between the printer 101 and the base station 103 is executed in response to an operation for shifting to the communication parameter automatic setting of the base station 103 by the user (S418). ). As a result, the printer 101 can acquire the latest communication parameters of the base station 103 and update the connection information stored by itself. By using the updated connection information, the printer 101 can wirelessly connect to the base station 103 (S419).

  In the above description, the example in which the user is notified of the change of the communication parameter of the base station 103 and the connection information of the printer 101 is updated has been described. For example, the base station 103 may be forced to execute the communication parameter automatic setting method according to an instruction from the printer 101. In this case, since the communication parameter automatic setting method is forcibly executed in the base station 103, the printer 101 automatically updates the connection information. In this case, the user may or may not be notified. The method of forcing can be realized by, for example, including a command for forcing the base station 103 to execute the communication parameter automatic setting method in a signal transmitted from the printer 101 to the base station 103.

  As described above, when the communication parameter of the base station 103 is changed, the printer 101 cannot be wirelessly connected, but it can be detected that the cause is the change of the communication parameter of the base station 103. In addition, by notifying the user that the communication parameter of the base station 103 has been changed, it is possible to notify that the connection information needs to be updated in order to reconnect the printer 101 to the base station 103. Furthermore, by automatically updating the connection information, it is possible to automatically recover the connection without making the user aware of the execution of the connection setting, and to reduce the user's trouble of resetting.

  In the above description, the BSSID is acquired as the first identification information by the communication parameter automatic setting method. As a result, identification information can be acquired without the user being aware of a communication device that has been successfully connected, and even if the connection fails after that, the cause of the connection failure is automatically detected. I can do it. However, the BSSID acquisition method may be other methods. For example, when a wireless connection failure occurs, input from the user may be received via the display processing unit 205 and the operation unit 206, and the input information may be used as the first identification information. As a result, for example, the user can visually identify the first identifier affixed to the housing of the base station 103 and input it, so that the base station 103 that is surely desired to be connected can be specified and connection is impossible. The cause can be determined. In the above description, an example in which BSSID is used as the first identification information and the second identification information has been described. However, these identification information may be any information as long as it is unique information that can identify the communication device. Of course it does not matter.

<< Embodiment 2 >>
In the first embodiment, the case where the printer 101 cannot be wirelessly connected to the base station 103 due to the change of the SSID of the base station 103 to be connected has been described. In the present embodiment, a case where the security scheme of the base station 103 is changed will be described. The system configuration used in the present embodiment is the same as that used in the description of the first embodiment. The configurations of the printer 101, the PC 102, and the base station 103 used in this embodiment are the same as those used in the description of the first embodiment. A specific method will be described below with reference to the sequence diagrams of FIGS. 3 and 6 and the flowchart of FIG.

  In the present embodiment, a case where the communication parameter changed by the user of the PC 102 in S411 of FIG. For example, it is assumed that the security scheme of the base station 103 is initially set to “WPA-PSK TKIP” at the start of this operation flow, and then changed to “WPA2-PSK AES” by the user of the PC 102 (S411).

  In this case, the security methods used by the printer 101 and the base station 103 are different, and the printer 101 cannot be wirelessly connected to the base station 103 (S416). A state in which this connection fails will be described with reference to the sequence diagram of FIG.

  The printer 101 stores connection information to the base station 103 by executing the communication parameter automatic setting method (S402). Therefore, the printer 101 tries to connect to the base station 103 using this connection information (S416, S702). The storage unit 208 of the printer 101 stores connection information to the base station 103, and the security method is “WPA-PSK TKIP” (S701).

  In order to connect to the base station 103, the printer 101 transmits a search request for searching the network, and starts detecting a network whose security method is “WPA-PSK TKIP” (S702). Upon receiving the search request, the base station 103 responds by including “WPA2-PSK AES”, which is a network security method built by itself, in the search response (S703). However, the printer 101 waits for a search response including a security method “WPA-PSK TKIP”. For this reason, the printer 101 cannot receive a search response whose security method includes “WPA-PSK TKIP”. In this case, the printer 101 may confirm that the SSID of the search response matches the SSID of the connection information stored in the printer 101 and that the base station 103 exists. However, even in that case, the printer 101 fails in the wireless connection because the security method differs between the connection information stored in itself and the search response (S704).

  At this point, the printer 101 does not know what caused the connection failure. That is, the printer 101 does not know whether the base station 103 does not exist, whether the communication parameter has been changed, or whether the connection cannot be made due to another factor. For this reason, the printer 101 investigates the cause of the wireless connection failure (S417). This process will be described with reference to FIG.

  In this embodiment, the base station 103 transmits a search response to the printer 101 in response to receiving the search request (S702) of the printer 101 (S703). For this reason, the printer 101 receives the search response (Yes in S501). Further, since the search response includes a security method different from the security method stored in the printer 101, the communication parameters do not match (S502). No). However, the search response is a signal transmitted by the base station 103. For this reason, the first identification information and the second identification information match (Yes in S503). Accordingly, the printer 101 can detect that the base station 103 exists and the security method, which is one of the communication parameters, has been changed in the base station 103 (S504). Thereafter, the printer 101 automatically transitions to the execution preparation state of the communication parameter automatic setting method (S505). Note that an instruction to execute the communication parameter automatic setting method may be notified to the user via the display processing unit 205, and the instruction may be executed by the user. In this case, the printer 101 is shifted to the execution preparation state of the communication parameter automatic setting method by the user's execution operation.

  If the SSID is not changed as described above, the printer 101 can determine that the base station 103 exists by receiving a search response having the same SSID as the connection information stored in the storage unit 208. Here, for example, when the security method has been changed, the printer 101 can determine that the communication parameters of the base station 103 have been changed without checking the BSSID by detecting that the SSID matches and the security method is different. . However, the SSID can be easily changed artificially. Therefore, even if the SSID included in the search response matches the SSID of the connection information, the printer 101 changes the communication parameter of the base station 103 even though the communication device that transmitted the search response may not be the base station 103. It is mistakenly judged that it was done.

  According to the method according to the present embodiment, even in such a case, the printer 101 can correctly identify whether or not the communication device that is the transmission source of the search response is the base station 103. In the method according to the present embodiment, the printer 101 compares the first identification information with the second identification information to determine whether or not the transmission source is the base station 103. These pieces of information are unique to the communication device. This is because different values are acquired from different transmission sources. As a result, according to the method according to the present embodiment, the printer 101 can determine whether or not the communication device that has transmitted the search response is the base station 103. Further, when it is determined that the transmission source of the search response is the base station 103, the printer 101 can determine whether or not the base station 103 has changed the communication parameter.

  After performing the connection failure cause investigation, the communication parameter automatic setting method between the printer 101 and the base station 103 is executed in response to an operation for shifting to the communication parameter automatic setting of the base station 103 by the user (S418). ). As a result, the printer 101 can acquire the latest communication parameters of the base station 103 and update the connection information stored by itself. By using the updated connection information, the printer 101 can wirelessly connect to the base station 103 (S419). Operations related to the execution of the communication parameter automatic setting method are the same as those in the first embodiment.

  Here, a case has been described in which the “authentication method” is mainly changed from “WPA-PSK TKIP” to “WPA2-PSK AES”. However, even when the “encryption scheme” such as “WPA2-PSK AES” is changed from “WPA2-PSK TKIP”, the wireless connection can be restored by the same processing. In the sequence of FIG. 6, the wireless connection failure is determined because the security method of the own device and the security method in the search response are different, but the present invention is not limited to this. For example, after the search response, a wireless connection request may be executed from the printer 101 to the base station 103, and the success / failure of the connection may be determined from the content of the wireless connection response transmitted from the base station 103 in response thereto.

  In step S502, the printer 101 determines whether or not the communication parameter matches the connection information. This determination may be performed for a plurality of communication parameters in a batch or may be performed sequentially. For example, in the first embodiment, the case where the SSID is changed among the communication parameters and the security method is changed in the present embodiment has been described. In this case, the printer 101 may execute a match determination between the communication parameters included in the connection response and the stored connection information for both the SSID and the security method, or may sequentially determine these one by one. Good. Further, the printer 101 may execute the security determination after the SSID match determination, or vice versa. In the case of sequentially determining the match, if there is even one different item, the match determination process may be stopped and it may be determined No in S502. In any case, when determining a match for a plurality of elements, the printer 101 determines No in S502 if the communication parameter and the connection information are different for any one element.

  According to the present embodiment, the printer 101 can automatically detect that the communication parameter of the base station 103 has been changed when the counterpart apparatus is the base station 103 to be connected. Furthermore, even when a counterpart device having the same SSID as the connection target base station 103 exists, it is possible to detect whether or not the counterpart device is the connection target base station 103. Thereby, the user's convenience can be ensured by detecting and notifying the cause of the connection failure without bothering the user. In particular, in the present embodiment, even when it seems that there is a base station 103 with the same SSID, it is possible to easily determine the cause of the connection failure.

<< Embodiment 3 >>
In this embodiment, a case where the security key of the security method of the base station 103 is changed will be described. The system configuration used in the present embodiment is the same as that used in the description of the first embodiment. The configurations of the printer 101, the PC 102, and the base station 103 used in this embodiment are the same as those used in the description of the other embodiments described above. A specific method will be described below with reference to the sequence diagrams of FIGS. 3 and 7 and the flowchart of FIG.

  In the present embodiment, a case will be described in which the communication parameter changed by the user of the PC 102 is the security key of the base station 103 in S411 of FIG. It is assumed that the security key of the base station 103 is set to “12345678” at the beginning of the operation flow and is changed to “ABCDEFGH” by the user of the PC 102 (S411).

  In this case, the security keys used by the printer 101 and the base station 103 are different, and the printer 101 cannot be wirelessly connected to the base station 103 (S416). A state in which this connection fails will be described with reference to the sequence diagram of FIG.

  The printer 101 stores the security key “12345678” as the connection information to the base station 103 by executing the communication parameter automatic setting method (S402) (S801). For this reason, the printer 101 sends a search request, which is a network search signal for searching the network, and starts detecting a network whose “SSID” and “security method” are the same as the self-device (S802). Here, when the base station 103 receives the search request, the base station 103 responds by including the security method of the network constructed by itself in the search response (S803).

  In the present embodiment, the user of the PC 102 does not change the SSID and the security method. Therefore, as a result of comparing the stored connection information with the communication parameters included in the search response, the printer 101 can confirm the base station 103 having the same SSID and security method. For this reason, the printer 101 transmits a wireless connection request to the base station 103 to execute wireless connection with the base station 103 (S804). Furthermore, the base station 103 responds to the printer 101 with a wireless connection response including “permitted wireless connection” (S805). Here, the printer 101 and the base station 103 confirm each other's security key. However, here, the printer 101 and the base station 103 hold “12345678” and “ABCDEFGH” as security keys, respectively (S806). For this reason, the printer 101 and the base station 103 fail in the key exchange process (S807), and a security key difference is detected in this processing stage (S808). Then, the printer 101 fails in wireless connection with the base station 103 (S416).

  At this point, the printer 101 does not know what caused the connection failure. That is, the printer 101 does not know whether the base station 103 does not exist, whether the communication parameter has been changed, or whether the connection cannot be made due to another factor. For this reason, the printer 101 investigates the cause of the wireless connection failure (S417). This process will be described with reference to FIG.

  In this embodiment, the base station 103 transmits a search response to the printer 101 in response to receiving the search request (S802) of the printer 101 (S803). For this reason, the printer 101 has received a search response (Yes in S501). The search response includes the same security method as the connection information stored in the printer 101, and the printer 101 determines that the security methods also match. However, in the connection process, the printer 101 detects that the security key is different from that of the base station 103 (No in S808 and S502). Here, the search response is a signal transmitted by the base station 103. For this reason, the first identification information and the second identification information match (Yes in S503). Accordingly, the printer 101 can detect that the base station 103 exists and the security key, which is one of the communication parameters, has been changed in the base station 103 (S504). Thereafter, the printer 101 automatically transitions to the execution preparation state of the communication parameter automatic setting method (S505). Note that an instruction to execute the communication parameter automatic setting method may be notified to the user via the display processing unit 205, and the instruction may be executed by the user. In this case, the printer 101 is shifted to the execution preparation state of the communication parameter automatic setting method by the user's execution operation.

  After performing the connection failure cause investigation, the communication parameter automatic setting method between the printer 101 and the base station 103 is executed in response to an operation for shifting to the communication parameter automatic setting of the base station 103 by the user (S418). ). As a result, the printer 101 can acquire the latest communication parameters of the base station 103 and update the connection information stored by itself. By using the updated connection information, the printer 101 can wirelessly connect to the base station 103 (S419). The operation related to the execution of the communication parameter automatic setting method is the same as in the other embodiments described above.

  As described above, the method according to the present embodiment can be operated in the same manner as in the first and second embodiments even when communication parameters not included in the search response are different. Thereby, for example, even when a wireless connection is accidentally executed for a communication apparatus having the same SSID or security method, the printer 101 can detect that the communication apparatus is erroneously connected. Specifically, a mismatch in some communication parameters is detected after the wireless connection is executed, and the process according to the present embodiment is executed. Here, since the search response can be received naturally because the wireless connection is being executed, S501 in FIG. 4 is Yes, and a partial mismatch of the communication parameters is confirmed, so S502 is No. Become. For this reason, the process which concerns on this embodiment can be started from S503. As a result, the above-described communication apparatus transmits a search response including second identification information different from that of the base station 103, so that the printer 101 can detect that the communication apparatus is not the base station 103. Similarly, even after the wireless connection to the base station 103 is executed, even if it is found that some of the communication parameters are different, the communication parameters can be changed to the printer 101 by executing the processing from S503 in FIG. Can be detected. Thereby, the user's convenience can be ensured by detecting and notifying the cause of the connection failure without bothering the user. In particular, in the present embodiment, when there appears to be a base station 103 having the same SSID and security method, it is possible to easily determine the cause of the connection failure.

  Here, the case where the security method is “WPA-PSK” or “WPA2-PSK” has been described. In the case of the security method “WEP”, there is no key exchange process (S807). However, when the printer 101 receives some encrypted data, it is detected that the security key is different at the decryption processing stage. In this case, when a security key mismatch is detected, the processing from S503 in FIG. 4 is started, and it can be detected that the communication parameter has been changed. Therefore, even in the case of the security method “WEP”, it is possible to restore the wireless connection.

<< Embodiment 4 >>
In the present embodiment, a case where the frequency band used in the wireless LAN is changed will be described. The IEEE 802.11 standard defines the specifications of “2.4 GHz band” and “5 GHz band” as frequency bands. Therefore, the base station 103 operates both of these frequency bands or operates only one of the frequency bands. In the present embodiment, a case where the user of the PC 102 switches the frequency band of the base station 103 from the 2.4 GHz band to the 5 GHz band in S411 will be described. The system configuration used in the present embodiment is the same as that used in the description of the first to third embodiments.

  FIG. 9 shows a functional block diagram of the printer 101 used in this embodiment. The difference from the block diagram (FIG. 2) of the printer 101 described in the first embodiment is that the printer 101 includes a plurality of wireless communication function units (a first wireless communication function unit 1001 and a second wireless communication function unit 1002). Can be used by switching between them. The PC 102 is also realized with the same configuration as the printer 101. However, the PC 102 includes a function unit for processing functions specific to the PC 102 instead of the printer function unit 201 in the printer 101. On the other hand, the configuration of the base station 103 used in the present embodiment is the same as that used in the description of the other embodiments 1 to 3 described above.

  In the present embodiment, when executing the communication parameter automatic setting method (S402 in FIG. 3), the printer 101 acquires a parameter “base station identifier” in addition to the communication parameter acquired in the case of the first embodiment. The base station identifier is identification information different from the BSSID. When the communication device has a plurality of sets of communication parameters such that the communication device can use a plurality of frequency bands, a different value is assigned to each of the plurality of sets. On the other hand, the base station identifier is a value specific to the base station 103 that does not depend on the use frequency band or the set of parameters. Further, the base station identifier is transmitted by the base station 103 included in a search response to a search request for searching the network. The printer 101 acquires this base station identifier and stores it as first identification information. A specific method will be described below with reference to the sequence diagrams of FIGS. 3 and 8 and the flowchart of FIG.

  In this embodiment, the communication parameter is changed by the user of the PC 102 in S411 of FIG. 3, but the changed communication parameter is the frequency band of the wireless LAN used by the base station 103. The use frequency band of the base station 103 is set to “2.4 GHz band” at the beginning of this operation flow, and is changed to “5 GHz band” by the user of the PC 102 (S411).

  In this case, the frequency bands used by the printer 101 and the base station 103 are different, and the printer 101 cannot be wirelessly connected to the base station 103 (S416). A state in which this connection fails will be described with reference to the sequence diagram of FIG.

  The printer 101 stores that the use frequency band is “2.4 GHz band” as connection information to the base station 103 by the communication parameter automatic setting method (S402) (S901). Accordingly, the printer 101 transmits a search request, which is a network search signal for searching the network, in the 2.4 GHz band, and starts detecting the network (S903). Here, the base station 103 operates in the 5 GHz band (S902). Accordingly, since the base station 103 cannot receive the search request (S903) transmitted in the 2.4 GHz band, the base station 103 does not transmit a search response (S904). For this reason, the printer 101 cannot confirm the presence of the base station 103. Normally, the printer 101 determines that connection is impossible, displays an error on the display processing unit 205, and completes the process.

  However, if the printer 101 according to the present embodiment cannot receive a search response, the printer 101 does not immediately determine that there is no base station 103 in the vicinity, and determines whether there is another usable frequency band ( S509). For example, when the 5 GHz band can be used, the printer 101 changes the use frequency band to the 5 GHz band (S905, S510), and transmits a search request again (S906).

  When receiving the search request in the 5 GHz band, the base station 103 responds with a search response (S907). Upon receiving the search response (S907, S501), the printer 101 acquires “base station identifier” included in the search response as second identification information. As described above, the base station identifier is a value unique to the base station 103 and does not depend on the use frequency band. At this time, since the communication parameter called the use frequency band is different, S502 is determined to be “No”, and the process proceeds to S503. The printer 101 compares the base station identifier of the stored connection information with the base station identifier included in the search response (S908, S503). Through this comparison process, the printer 101 can confirm whether the desired base station 103 is activated. Here, since the search response is a signal transmitted from the base station 103 (S907), the base station identifier stored in the printer 101 matches the base station identifier included in the search response (Yes in S503). Accordingly, the printer 101 can detect that the base station 103 exists and the use frequency band is changed (S504). Thereafter, the printer 101 automatically transitions to the execution preparation state of the communication parameter automatic setting method (S505). Note that an instruction to execute the communication parameter automatic setting method may be notified to the user via the display processing unit 205, and the instruction may be executed by the user. In this case, the printer 101 is shifted to the execution preparation state of the communication parameter automatic setting method by the user's execution operation.

  After performing the connection failure cause investigation, the communication parameter automatic setting method between the printer 101 and the base station 103 is executed in response to an operation for shifting to the communication parameter automatic setting of the base station 103 by the user (S418). ). As a result, the printer 101 can acquire the latest communication parameters of the base station 103 and update the connection information stored by itself. By using the updated connection information, the printer 101 can wirelessly connect to the base station 103 (S419). Operations such as user notification related to the execution of the communication parameter automatic setting method are the same as in the other embodiments described above.

  According to the present embodiment, even when the communication partner device cannot be searched due to the change of the use frequency band, the search target partner device can be automatically found by executing the search in another frequency band. As a result, it is possible to clearly indicate to the user who does not know the change of the frequency band of the base station that the printer 101 cannot connect to the base station 103 and to instruct that the communication parameter automatic setting should be executed again. In addition, since the printer 101 and the base station 103 perform automatic setting of communication parameters without user operation, a connection is automatically established even when there is a change in the use frequency band. Will improve.

  The preferred embodiments of the present invention have been described above. However, this is an example for explaining the present invention, and the scope of the present invention is not intended to be limited to these embodiments. The embodiment can be variously modified without departing from the gist of the present invention. For example, although the present embodiment has been described using the printer 101, the above-described processing can also be executed in a digital camera, a mobile phone, or the like that is also equipped with a wireless communication function.

  However, since these devices are carried and used, it is assumed that they are connected to various wireless LANs. Therefore, in these cases, when the wireless connection fails, the BSSID stored in the terminal itself or the function of searching for the base station 103 that operates with the base station identifier has a further effect by providing a setting capable of selecting valid / invalid. can get. In other words, the validity / invalidity of the function of the present invention may be selected according to the main application of the communication apparatus, the power supply method (AC power supply or battery drive), and the like. Thereby, it is possible to suppress the power consumption for the communication device to execute the search for the base station 103, and it is possible to prevent a situation where there is no remaining power for executing the main application.

  Also, the above description has been made with reference to an IEEE 802.11-compliant wireless LAN as an example. However, the present invention may use other wireless media. Moreover, you may implement in wired communication media, such as wired LAN.

<< Other Embodiments >>
The present invention can also be realized by executing the following processing. That is, software (program) that realizes the functions of the above-described embodiments is supplied to a system or apparatus via a network or various storage media, and a computer (or CPU, MPU, or the like) of the system or apparatus reads the program. It is a process to be executed.

Claims (11)

Sharing means for sharing communication parameters for wireless connection with other communication devices with the other communication devices ;
Request means for requesting a wireless connection using the communication parameters ;
Failure to wirelessly connect said requesting means requests, determining means for determining whether or not a request by said request means is made to the other communication apparatus,
According to the determination result by said determining means, and notification control means for notifying that the setting of the other communication device is changed,
Communication apparatus characterized by having a. A storage means for storing identification information of the other communication device;
The determination means determines whether or not a request by the request means is made to the other communication device based on the identification information.
The communication apparatus according to claim 1.   The storage means stores the identification information of the other communication device together with the communication parameter when the wireless connection with the other communication device using the communication parameter is successful.
  The communication device according to claim 2.   If the wireless connection requested by the request unit fails, the request unit further includes an acquisition unit that acquires identification information of the destination device from the destination device requested by the request unit;
  The determination unit determines whether or not a request by the request unit is made to the other communication device based on the identification information of the other communication device and the identification information of the destination device;
  The communication apparatus according to claim 2 or 3, wherein   An input means for allowing a user to input identification information of the other communication device;
  The communication apparatus according to any one of claims 2 to 4, wherein the communication apparatus is characterized in that:   The identification information of the other communication device is a MAC address of the other communication device.
  The communication device according to any one of claims 2 to 5, wherein: The communication parameter includes at least one of an SSID, a security method, a security key, and a frequency band to be used .
Communication apparatus according to any one of claims 1 6, characterized in that.   The notification control unit is configured to notify the user that the setting of the other communication device has been changed by displaying on the display unit.
  The communication device according to claim 1, wherein the communication device is a device.   In accordance with the determination result by the determination unit, the sharing unit again executes a communication parameter sharing process for wireless connection with the other communication device.
  The communication apparatus according to claim 1, wherein the communication apparatus is configured as described above.   A communication device control method comprising:
  A sharing step of sharing communication parameters for wireless connection with another communication device with the other communication device;
  A requesting step for requesting a wireless connection using the communication parameters;
  A determination step of determining whether a request by the request unit is made to the other communication device when the wireless connection requested in the request step fails;
  In accordance with the determination result in the determination step, a notification control step for notifying that the setting of the other communication device has been changed,
  A control method characterized by comprising: The program for functioning a computer as each means with which the communication apparatus of any one of Claim 1 to 9 is provided.

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