JP5649694B2 - Communication device, control method, and program - Google Patents

Description

  The present invention relates to a communication device, a control method, and a program.

  There are many setting items that must be set before use when performing wireless communication represented by a wireless LAN compliant with the IEEE 802.11 standard series. Specifically, SSID as a network identifier, an encryption method, an encryption key, an authentication method, an authentication key, and the like can be mentioned. It is very complicated for a user to manually set communication parameters for performing wireless communication. Work.

  For this reason, various manufacturers have devised automatic setting methods for easily setting communication parameters in a wireless communication device. In these automatic setting methods, communication parameters are automatically set by providing communication parameters from one device to the other communication device using a predetermined procedure and message between connected communication devices. It is configured.

  Patent Document 1 discloses an example of automatic setting of communication parameters in communication in a wireless LAN ad hoc mode (hereinafter referred to as ad hoc communication). Further, Non-Patent Document 1 discloses Wi-Fi Protected Setup (hereinafter, WPS), which is an industry standard for automatic setting of communication parameters between an access point (base station) and a station (terminal station). Further, Non-Patent Document 2 discloses Wi-Fi Protected Access (hereinafter referred to as WPA) which is an industry standard such as an encryption method, an encryption key, an authentication method, and an authentication key in wireless communication.

JP 2006-31139 A

Wi-Fi CERTIFIED for Wi-Fi Protected Setup: Easing the User Experience for Home and Small Office Wi-Fi Networks, http://www.wi-fi.org/wp/wifi-protected-setup Wi-Fi Protected Access Enhanced Security Implementation Based on IEEE P802.11i standard

  In this way, when the roles of a communication device that provides communication parameters (hereinafter referred to as a providing device) and a communication device that receives (hereinafter referred to as a receiving device) are determined in advance as in WPS, the transfer direction of communication parameters is also unique. Will be determined.

  However, when the roles of the providing device and the receiving device are not determined in advance, the transfer direction of the communication parameter cannot be uniquely determined.

  Furthermore, if a plurality of communication devices become providing devices, the receiving device cannot determine from which providing device the communication parameter should be received.

  In this case, if the user is allowed to select which communication device is the providing device and which communication device is the receiving device, there is a problem that the operability of the user is impaired.

  The above problem can also occur when a new communication device is added to a network that has already been constructed among a plurality of communication devices. In this case, it is desirable that the communication device participating in the network is the providing device, and the newly participating communication device is the receiving device to receive the communication parameters of the network. However, if the roles of the providing device and the receiving device are not determined in advance, it is not possible to set appropriate communication parameters for the newly participating communication device.

  Further, the above problem is not limited to communication parameters for performing wireless communication, but may similarly occur for communication parameters for performing communication by wired or the like that needs to be set in communication between communication apparatuses.

  The present invention has been made in view of the above problems, and even when the role of the communication parameter is automatically set is not determined in advance, the communication parameter can be appropriately set without impairing the operability of the user. The purpose is to be able to set.

In order to achieve the above object, a communication apparatus according to the present invention is a communication apparatus that operates as a providing apparatus that provides communication parameters for wireless communication or a receiving apparatus that receives communication parameters. When the start of the process is instructed and operates as the providing apparatus, a transmission unit that transmits information indicating the providing apparatus to a participating network, and when operating as the receiving apparatus, from another communication apparatus Response means for responding to the request with identification information of a device operating as a providing device , and completion means for sending a completion notification to the network when the communication parameter provision processing is completed.

  According to the present invention, it is possible to appropriately set communication parameters without impairing the operability of the user even when the role is not determined in advance when the communication parameters are automatically set.

It is a block diagram showing an example of the composition of the communication device (providing device or receiving device) concerning one embodiment of the present invention. It is a block diagram showing an example of a structure of the software functional block which each communication apparatus performs. It is the figure which showed the apparatus A and the apparatus B which are communication apparatuses. FIG. 10 is a diagram illustrating an example of a processing sequence of communication parameter automatic setting processing performed between the device A and the device B when the setting button 106 is pressed in the device A and the device B. Communication in the case where the setting button 106 is pressed in the device A and the device B to determine which of the providing device or the receiving device operates between the device A and the device B, and communication parameter automatic setting processing is performed It is the flowchart which showed the flow of control processing. It is a flowchart which shows the detail of the communication parameter provision process I (step S524). It is a flowchart which shows the detail of a communication parameter reception process (step S517). FIG. 2 is a diagram illustrating a device A, a device B, a device C, and a network B. FIG. 6 is a diagram illustrating an example of a processing sequence of communication parameter automatic setting processing performed when the setting button 106 of the device B and the device C is pressed in a state where the network B is configured by the devices A and B. is there. It is a flowchart which shows the detail of the communication parameter provision process II (step S531). It is a flowchart which shows the detail of a proxy response process (step S519). It is a figure which shows the combination employ | adopted as an authentication system and an encryption system. It is a figure which shows the comparison table of the possession key and key exchange sequence in a key exchange algorithm. It is the sequence diagram (the 1) of key exchange processing. It is the sequence diagram (the 2) of key exchange processing. It is the sequence diagram (the 3) of a key exchange process. It is the sequence diagram (the 4) of a key exchange process. It is a flowchart which shows a key exchange algorithm selection algorithm.

  Hereinafter, a communication device according to each embodiment of the present invention will be described in detail with reference to the drawings. In the following description, a case where a wireless LAN system compliant with the IEEE 802.11 series is used will be described. However, the communication mode is not necessarily limited to the case where a wireless LAN system compliant with IEEE 802.11 is used.

1. Hardware Configuration of Communication Device First, the hardware configuration of the communication device according to the present embodiment will be described. FIG. 1 is a block diagram showing an example of the configuration of a communication apparatus (providing apparatus or receiving apparatus) according to an embodiment of the present invention.

  Reference numeral 101 denotes the entire communication apparatus. Reference numeral 102 denotes a control unit that controls the entire communication device by executing a computer program stored in the storage unit 103. The control unit 102 also performs communication parameter setting control with other communication devices.

  A storage unit 103 stores a computer program executed by the control unit 102 and various types of information such as communication parameters. Various processes to be described later in the communication apparatus are realized by the control unit 102 executing a computer program stored in the storage unit 103.

  Reference numeral 104 denotes a wireless unit for performing wireless communication. Reference numeral 105 denotes a display unit for performing various displays, and has a function of outputting visually recognizable information such as an LCD or LED, or a sound output of a speaker or the like.

  Reference numeral 106 denotes a setting button for giving a trigger (start instruction) for starting the communication parameter setting process. When the control unit 102 detects an operation of the setting button 106 by the user, the control unit 102 executes processing to be described later.

  Reference numeral 107 denotes an antenna control unit, and reference numeral 108 denotes an antenna. Reference numeral 109 denotes an input unit for the user to perform various inputs.

2. Functional Block of Communication Device FIG. 2 is a block diagram illustrating an example of a configuration of software functional blocks executed by each communication device in communication parameter automatic setting processing to be described later.

  Reference numeral 201 denotes the entire communication apparatus. Reference numeral 202 denotes a communication parameter automatic setting function block. In this embodiment, when the functional block operates, an automatic setting process of communication parameters for performing wireless communication such as an SSID as a network identifier, an encryption method, an encryption key, an authentication method, and an authentication key is performed.

  Reference numeral 203 denotes a packet receiver for receiving packets related to various communications. Reception of the beacon (notification signal) is performed by the packet receiving unit 203. Reference numeral 204 denotes a packet transmission unit for transmitting packets related to various communications. The beacon is transmitted by the packet transmission unit 204. It is assumed that various information (self-information) of the transmission source communication device is added to the beacon.

  A search signal transmission unit 205 controls transmission of a search signal such as a probe request. The probe request can also be referred to as a network search signal for searching for a desired network. Transmission of the probe request is performed by the search signal transmission unit 205. The search signal transmission unit 205 also transmits a probe response that is a search response signal for the received probe request.

  A search signal receiving unit 206 controls reception of a search signal such as a probe request from another communication apparatus. The search signal reception unit 206 receives the probe request. The search signal receiving unit 206 also transmits a probe response. It is assumed that various information (self-information) of the transmission source communication device is added to the search signal and the search response signal.

  A network control unit 207 controls communication connection processing to the network. The wireless communication connection processing to the wireless LAN ad hoc network is performed by the network control unit 207.

  In the communication parameter automatic setting function block 202, 208 is an automatic setting control unit that controls various protocols in the communication parameter automatic setting process.

  Reference numeral 209 denotes a communication parameter providing unit that provides communication parameters to other communication apparatuses. Of the communication parameter automatic setting processing described later, the communication parameter providing processing is performed by the communication parameter providing unit 209 under the control of the automatic setting control unit 208.

  A communication parameter receiving unit 210 receives communication parameters from other communication apparatuses. Of the communication parameter automatic setting process described later, the communication parameter receiving process is performed by the communication parameter receiving unit 210 under the control of the automatic setting control unit 208.

  The automatic setting control unit 208 also determines whether or not the elapsed time since the communication parameter automatic setting process has started exceeds the time limit for the communication parameter automatic setting process. When it is determined that the time limit has been exceeded, the automatic setting process is stopped under the control of the automatic setting control unit 208.

  A role determination unit 211 determines a role in communication parameter automatic setting processing.

  A setting notification control unit 212 controls processing related to the notification of the start and end of communication parameter automatic setting processing. The setting notification control unit 212 performs transmission / reception processing of a start notification message and a completion notification message in the providing device described later.

  Reference numeral 213 denotes a beacon control unit that controls the transmission timing of a beacon (notification signal). A beacon transmission algorithm in the IEEE 802.11 wireless LAN ad hoc network will be described.

  Transmission of a beacon in an ad hoc network is performed in an autonomous and distributed manner among all communication devices constituting the network. The beacon transmission interval (beacon period) is determined by the communication device that first created the ad hoc network. Normally, a beacon is transmitted from one of the communication devices at an interval of about 100 ms. In the ad hoc network, any one communication device starts transmission of a beacon to form a network.

  The timing of transmitting a beacon is controlled by a parameter called a contention window (random number generation range, hereinafter CW). Each communication device in the network obtains a random value (CWrand) from 0 to CW when it is time to transmit a beacon. A time obtained by multiplying this CWrand by a predetermined interval (slot time) is set as a waiting time (backoff time) until beacon transmission.

  Next, the waiting time until the beacon transmission is decremented by the slot time, and the beacon is transmitted when the waiting time becomes zero. If the local communication apparatus receives a beacon from another communication apparatus before transmitting the beacon, the process of transmitting the beacon is stopped.

  By comprising in this way, the collision of the beacon transmitted from each communication apparatus can be prevented. Since each communication device on the ad hoc network selects a random number between 0 and CW, the communication device that has selected the smallest CWrand among the communication devices constituting the network transmits a beacon.

  For example, if the same CW is set as an initial value for each communication device, the beacon transmission probability by each communication device is the same, and as a result, the number of beacons transmitted per unit time by each communication device Are almost the same. In other words, the beacon transmission frequency (transmission ratio) by each communication device is the same.

  On the other hand, when one communication device on the network sets CW to a value smaller than the initial value, the probability that the communication device transmits a beacon becomes higher than other communication devices. That is, CW can be said to be a parameter for determining the beacon transmission probability, or a parameter for determining the number of beacons transmitted per unit time. Or it can also be called the parameter for determining the transmission rate of the beacon which each communication apparatus transmits.

  Furthermore, the CW can be paraphrased as a parameter for determining the timing for transmitting a beacon and a parameter for determining a waiting time until beacon transmission.

  Note that the value of CW can be changed in a range from CWmin (minimum value) to CWmax (maximum value), and when set to CWmin, the number of beacon transmissions per unit time is maximized. In each communication device, CWinit (> CWmin) is set as an initial value, and beacon transmission is performed using the initial value while the communication parameter automatic setting process is not being executed.

3. Explanation of communication parameter automatic setting process (1)
Next, details of the communication parameter automatic setting processing will be described.

3.1 Network Configuration First, a network configuration in which communication parameter automatic setting processing is executed will be described.

  FIG. 3 is a diagram illustrating a communication device A300 (hereinafter, device A) and a communication device B301 (hereinafter, device B), which are communication devices according to the present embodiment. These communication apparatuses are assumed to have the hardware configuration and functional configuration shown in FIGS. 1 and 2 described above.

  Further, it is not determined whether the device A and the device B operate as a communication parameter providing device or a receiving device, and the network A 302 (hereinafter referred to as network A) and the network B 303 (hereinafter referred to as network) are respectively determined. B) is created.

  Device A and device B discover each other's communication devices and determine which communication device is the providing device. As a result, communication parameters are provided from the communication device serving as the providing device to the communication device serving as the receiving device.

  Note that the network A and the network B are ad hoc networks created by the devices A and B, respectively. The ad hoc network is called an IBSS (Independent Basic Service Set), and each network is distinguished by a BSSID which is a network identifier.

  Here, the BSSID is a network identifier having a random value generated by a communication device that creates a network. The SSID is a network identifier that can be set in advance in the communication apparatus or can be set by the user to an arbitrary value, and is different from the BSSID. Further, as is apparent from the above description, the BSSID is not a communication parameter provided from the providing device to the receiving device by the communication parameter automatic setting process.

3.2 Processing Sequence of Communication Parameter Automatic Setting Processing FIG. 4 shows communication parameter automatic setting processing performed between the device A and the device B when the setting button 106 is pressed in the devices A and B. It is the figure which showed an example of the processing sequence of.

  When the setting button 106 is pressed in each of the devices A and B, the device A creates a unique network A (F401), and the device B also creates a unique network B (F402). Here, it is assumed that the setting button 106 of the device B is pressed first and the network of the device B is created first.

  In “device A” and “device B”, a “providing device candidate” is set (F403, F404) indicating that the operation role (hereinafter, “role”) has not been determined by either the providing device or the receiving device. Device A and device B then start timer T1, which is the time until the role is determined (F405, F406).

  The devices A and B transmit beacons (notification signals) including an information element (Information Element) indicating that the created network has a communication parameter automatic setting processing function (F407, F408). Or the beacon (notification signal) containing the information element which notifies that it is in an automatic setting process is transmitted (F407, F408). Note that the beacon may further include an information element indicating “providing device candidate” which is the current role.

  Since the beacons (F407 and F408) include different BSSIDs in the network A and the network B, the communication device that has received the beacon recognizes which beacon is transmitted from which communication device. be able to.

  Next, the device B transmits a search signal B (F409). Similarly to the beacon, the search signal B includes an information element indicating that it has a communication parameter automatic setting processing function. It is also assumed that an information element indicating that automatic setting processing is being performed and an information element indicating “providing apparatus candidate” which is the current role are also included.

  Upon receiving the search signal B (F409) transmitted from the device B, the device A transmits the search response signal A (F410) to the device B. Note that, similarly to the beacon and the search signal B, the search response signal A (F410) also includes an information element indicating that it has a communication parameter automatic setting processing function. Further, it is assumed that an information element indicating that automatic setting processing is being performed and an information element indicating “providing device candidate” which is the current role are included.

  Here, when the timer T1 expires without detecting the providing device in the device B (F411), the device B sets its role to the providing device (F412).

  Subsequently, the device A transmits a search signal A (F413). It is assumed that the search signal A (F413) transmitted from the device A also includes an information element indicating that the communication parameter automatic setting processing function is provided. Further, it is assumed that an information element indicating that automatic setting processing is being performed and an information element indicating “providing device candidate” which is the current role are included.

  When device B receives search signal A (F413) transmitted from device A, device B transmits search response signal B (F414) to device A. It is assumed that the search response signal B (F414) also includes an information element indicating that it has a communication parameter automatic setting processing function, like the beacon and the search response signal A. Further, it is assumed that an information element indicating that automatic setting processing is being performed and an information element indicating the current role are included.

  At this time, since the role of the device B is determined as “providing device”, the search response signal B includes an information element indicating “providing device” as the current role. However, in addition to the information element indicating “providing device”, an information element indicating that the communication parameter can be provided may be added.

  Upon receiving the search response signal B (F414) transmitted from the device B, the device A confirms that the role of the device B is a providing device and that communication parameters can be provided.

  Therefore, the device A stops the timer T1 (F415), sets its role to the receiving device (F416), and participates in the network B created by the device B (F417).

  As a result, the communication messages (protocol messages) exchanged in the communication parameter automatic setting protocol process can be transmitted and received between the devices A and B. As a result, the communication parameter providing process I is started in the apparatus B, and the communication parameter receiving process is started in the apparatus A (F418, F419).

  Here, the automatic setting protocol processing refers to processing for transmitting / receiving various communication messages determined in advance to provide communication parameters from the providing device to the receiving device. In WPS, the above protocol processing is called a registration protocol (see Non-Patent Document 1).

  In this embodiment, in order to simplify the description, a communication parameter provision start message (F420) is transmitted from the receiving apparatus to the providing apparatus, and the providing apparatus provides communication parameters to the receiving apparatus in response to the message (F420). Processing is to be performed (F421). When the provision is completed, a communication parameter provision completion message (F422) is transmitted.

  At the time when device A joins network B (F417), since communication parameters such as an encryption key and an authentication key are not set in device A, device A performs encryption and authentication with device B. The communication used cannot be performed.

  In the above description, the search signal and the search response signal are used in determining the role between the device A and the device B. However, the role may be determined using information elements included in the beacons transmitted and received mutually without transmitting / receiving the search signal and the search response signal.

  Returning to FIG. Device A participates in the network created by device B (F417) and starts communication parameter reception processing I (F419), and transmits a communication parameter provision start message to device B (F420). In addition, when receiving the communication parameter provision start message, the device B as the providing device performs communication parameter provision processing on the device A (F421). When the communication parameter provision processing is completed, apparatus B transmits a communication parameter provision completion message to apparatus A (F422). Thereby, the communication parameter providing process I and the communication parameter receiving process are completed (F423, F424), and the communication parameters are shared between the apparatuses A and B.

  As a result, apparatus A and apparatus B can perform communication connection processing using the shared communication parameters.

  Note that by starting the communication connection process simultaneously with the end of the communication parameter providing process I, communication between the apparatus A and the apparatus B is possible without forcing the user to perform an operation. In this case, the communication device may transmit a connection request signal that explicitly indicates that communication connection processing has started.

  In the ad hoc mode, the association process as in the infrastructure mode is not performed, but the communication device that has requested the connection can be immediately recognized by receiving the connection request signal.

  For example, in the present embodiment, the device B transmits the communication parameter of the network B to the device A, and performs communication connection processing using the communication parameter. In this case, when the device A transmits a connection request signal to the device B, the device B can know that the device A has joined the network B, and the number of participants can be easily grasped.

  Alternatively, the communication connection process may be confirmed with the user before the communication connection process is started, and the communication connection process may be started in response to an operation from the user. For example, when the communication parameter providing process I ends, the display unit 105 displays a message prompting the user to select whether or not to start the communication connection process, and when the user inputs via the input unit 109, the communication is performed. You may make it start a connection process.

  Further, the device B may be configured to transmit a communication parameter indicating a network different from the network B to the device A. For example, a communication parameter for performing communication in the network C may be provided from the device B to the device A, and the devices A and B may communicate with each other on the network C after the provision. In this case, the device A or the device B is configured to start the communication connection process triggered by the detection of the other communication device on the network C.

3.3 Flow of Communication Control Processing in Each Communication Device Next, a flow of communication control processing in each communication device when performing communication parameter automatic setting processing will be described.

  FIG. 5 is a flowchart showing the flow of communication control processing in each communication device when communication parameter automatic setting processing is performed.

  Hereinafter, communication control processing executed by each communication device will be described with reference to this flowchart.

  First, when the setting button 106 for instructing the start of the communication parameter automatic setting process is pressed, the communication apparatus recognizes this (step S501).

  The communication device in which the setting button 106 has been pressed checks whether it is already participating in the network (step S502). Here, the case of participating in a network refers to a case where a network is configured using communication parameters shared by, for example, communication parameter automatic setting processing already performed with another communication device. Note that the processing when participating in the network will be described later with reference to FIG.

  If it is determined in step S502 that the user does not participate in the network, the network is created by itself in order to determine the role (step S503). And after setting a role to a provision apparatus candidate (step S504), the timer T1 is started (step S505).

  In step S506, beacon transmission is started. The beacon transmitted at this time may include an information element indicating “providing device candidate” which is the current role.

  Then, the providing device search process is performed until the providing device is found or the timer T1 expires (steps S507 to S512).

  Specifically, when the timer T1 has not expired (No in step S507), each communication device determines whether a search signal (probe request) from another communication device has been received (step S508). And when it determines with having received the search signal from another communication apparatus, in response to this, a search response signal (probe response) is transmitted (step S509).

  Further, it also transmits a search signal (probe request) (step S510) and waits for reception of the search response signal (probe response) (step S511).

  When the search response signal is received (Yes in step S511), it is determined whether the role of the other communication device indicated by the information element included in the received search response signal is the providing device (step). S512). If it is determined that the role of the other communication device is the providing device, the timer T1 is stopped and the role of the communication device is set in the receiving device (steps S513 and S514).

  Further, the communication device set as the receiving device participates in the network created by the providing device (step S515), and transmits a beacon including an information element indicating that its role is “receiving device” ( Step S516).

  At this time, since communication parameters are not provided from the providing device, communication using encryption and authentication cannot be performed in the participating network. The receiving apparatus that has joined the network starts the communication parameter receiving process (step S517). Details of the communication parameter reception process will be described later.

  When the communication parameter reception process is completed in step S517, the communication connection process is enabled.

  Thereafter, the communication apparatus determines whether or not a start notification has been received (step S518), and if a start notification is received, performs a proxy response process (step S519). Details of the processing in steps S518 and S519 will be described later with reference to FIG. 7 and the like together with the processing in steps S525 to S532 (processing when the own communication apparatus is participating in the network).

  On the other hand, if it is determined in step S507 that the communication device whose role is the providing device cannot be found before the timer T1 expires, its own role is set in the providing device (step S520).

  And it transmits to the beacon including an information element indicating that its role is “providing device” (step S521). Further, it is determined whether or not a search signal from another communication device has been received (step S522). If it is determined that a search signal from another communication device has been received, a response to the search signal is received. A signal is transmitted (step S523).

  Further, the communication device set as the providing device starts communication parameter providing processing I (step S524). Details of the communication parameter providing process I (step S524) will be described later.

  When the communication parameter providing process is completed in step S524, the communication apparatus proceeds to step S518.

  In steps S508 to S512, the method (active scan) of searching for a providing device by waiting for reception of a search response signal (probe response) to the search signal (probe request) has been described. However, the present invention is not limited to this.

  As described above, since the providing apparatus transmits a beacon to which an information element indicating that communication parameter automatic setting processing is being performed is added, the receiving apparatus waits for the beacon to be transmitted for a certain period of time. (Passive scan) may be used.

3.4 Flow of Communication Parameter Providing Process I Next, details of the communication parameter providing process I (step S524) will be described. FIG. 6A is a flowchart showing details of the communication parameter provision processing I (step S524).

  When a communication parameter provision start message is received from the receiving device (Yes in step S601), the providing device starts providing communication parameters (step S602). The communication parameters provided at this time are the network communication parameters created in step S503.

  In step S603, it is determined whether the provision of communication parameters has been completed. If it is determined in step S603 that the provision of communication parameters has been completed, the process proceeds to step S606, and a communication parameter provision completion message is transmitted to the receiving apparatus.

  Further, in step S607, a display indicating that the communication parameter automatic setting process has been successful is performed.

  Specifically, the display unit 105 displays a message on the LCD, and a display indicating that the communication parameter automatic setting processing has succeeded so that the user can identify the LED by blinking, lighting, color, sound, or the like. Do.

  On the other hand, if an error has occurred in step S603, the process proceeds to step S604 to display that an error has occurred in the communication parameter automatic setting process.

  Specifically, it indicates that an error has occurred in the communication parameter automatic setting process so that the display unit 105 can display a message on the LCD and the user can identify the LED by blinking, lighting, color, or sound. Display.

3.5 Flow of Communication Parameter Receiving Process Next, details of the communication parameter receiving process (step S517) will be described. FIG. 6B is a flowchart showing details of the communication parameter reception process (step S517).

  In order to request provision of communication parameters, the receiving apparatus transmits a communication parameter provision start message to the providing apparatus (step S611), and starts receiving communication parameters from the providing apparatus (step S612). .

  In step S613, it is determined whether reception of communication parameters is completed. If it is determined in step S613 that reception of communication parameters has been completed, the process advances to step S616 to display that reception of communication parameters has been completed.

  Specifically, the display unit 105 displays a message on the LCD or displays that the communication parameter has been successfully received so that the user can identify the LED by blinking, lighting, color, sound, or the like.

  On the other hand, if an error has occurred in step S614, the process proceeds to step S615 to display that an error has occurred in the communication parameter reception process.

  Specifically, the display unit 105 displays a message on the LCD, or a display indicating that an error has occurred in the communication parameter reception process so that the user can identify the LED by blinking, lighting, color, or sound. I do.

4). Explanation of communication parameter automatic setting process (2)
Next, communication parameter automatic setting processing when a communication device newly joins an established ad hoc network will be described. Note that an established ad hoc network refers to an ad hoc network configured by a plurality of communication devices based on communication parameters shared between communication devices that have performed communication parameter automatic setting processing.

4.1 Network Configuration FIG. 7 illustrates a second communication device A300 (hereinafter referred to as device A), a first communication device B301 (hereinafter referred to as device B), a third communication device C700 (hereinafter referred to as device C), and 1 is a diagram showing a network B. FIG. Note that the devices A, B, and C have the hardware configuration and the functional configuration shown in FIGS. 1 and 2 described above.

  Here, the communication parameter automatic setting process when the setting button 106 of the device B and the device C is pressed when the device C participates in the network B composed of the devices A and B will be described below.

4.2 Processing Sequence of Communication Parameter Automatic Setting Processing FIG. 8 is performed when the setting button 106 of the device B and the device C is pressed while the network B is configured by the device A and the device B. It is the figure which showed an example of the processing sequence of the automatic setting process of a communication parameter.

  It is assumed that device A receives communication parameters from device B through communication parameter automatic setting processing, and has already participated in network B that performs communication using the communication parameters (F421, F422). Further, it is assumed that the device C has not yet received communication parameters.

  The device B participates in the network B by using the communication parameter already shared with the device A by the communication parameter automatic setting process. When the setting button 106 of the device B is pressed by the user, the device B sets its role to the providing device (F801).

  Subsequently, apparatus B activates notification processing (F802). After starting the notification process, apparatus B transmits a start notification message (F803), and increases the transmission frequency (transmission ratio, number of transmissions) per unit time of the beacon.

  The device A that has received the start notification message (F803) activates proxy response processing (F804), and reduces the beacon transmission frequency.

  As described above, when the device B increases the beacon transmission frequency and the device A reduces the beacon transmission frequency, the newly joining device C detects the providing device B in a shorter time. Is possible.

  On the other hand, when the setting button 106 of the device C is operated by the user, the device C creates a unique network C, sets the role to “providing device candidate”, starts the timer T1, and starts beacon transmission. . In FIG. 8, the description of these processes is omitted.

  The device C further transmits a search signal C to detect the providing device (F805). In response to the search signal C (F805) transmitted from the device C, the devices A and B in the network B return search response signals A and B (F806 and F807). In addition, the device B that has returned the search response signal B (F806) starts communication parameter provision processing II (F811).

  Here, when the device A returns the search response signal A (F807), the device A stores the identification information (MAC address) of the device B as the providing device in the search response signal and returns it.

  When device B returns search response signal B (F806), device B stores an information element indicating that it is a providing device in search response signal B (F806) and returns it. . As a result, the device C can reliably detect the device B, which is the providing device, even when the search response signal is received from any communication device in the network B.

  Upon detecting the presence of the providing device, device C sets its role as the receiving device (F808). Then, it participates in the network B (F809), and starts reception processing of communication parameters necessary for communication in the network B from the providing device B (F810).

  Then, the device C transmits a communication parameter provision start message (F812), and the device B as the providing device performs communication parameter provision processing on the device C as the receiving device (F813). When the communication parameter provision processing is completed, apparatus B transmits a communication parameter provision completion message to apparatus C (F814). Further, a completion notification message is transmitted to apparatus A (F815).

  Thereby, the communication parameter providing process II and the communication parameter receiving process are completed (F816, F817), and the communication parameters are shared between the device C and the device B (and the device A).

  Further, the device B further returns the increased beacon transmission frequency to the original, and ends the notification process (F819).

  In the device A that has received the completion notification message from the device B, the reduced transmission frequency of the beacon is restored, and the proxy response process is terminated (F818).

  As described above, the user can automatically join the device C to the network B only by operating the setting button 106.

  In the description of FIG. 8, the case where the setting button 106 of the device B is operated has been described. However, the setting button 106 of the device A may be operated. Even when the setting button 106 of the device A is operated, the device C can similarly participate in the network A as shown in FIG.

4.3 Flow of Communication Control Processing in Communication Device Next, in a state where the network B is configured by the device A and the device B, the communication parameter is automatically set by pressing the setting button 106 of the device B and the device C. A communication control process in each communication apparatus when performing the process will be described with reference to FIG.

  First, the communication control process in apparatus B will be described. When the setting button of apparatus B is pressed, apparatus B recognizes this (step S501).

  The device B whose setting button 106 has been pressed determines that it is currently participating in the network (Yes in step S502), and sets the role to the providing device (step S525). Then, the beacon is transmitted by including an information element indicating that its own role is “providing device” and an information element indicating that automatic setting processing is being performed (step S526).

  Subsequently, apparatus B starts notification processing. Specifically, in step S527, the transmission frequency (transmission ratio, number of transmissions) per unit time of the beacon is increased (first changing step).

  In an IEEE 802.11 wireless LAN ad hoc network, it is specified that a communication device that returns a search response signal (probe response) is a communication device that transmits a beacon immediately before receiving a search signal (probe request). ing.

  Therefore, in step S527, CW is set to a value smaller than the initial value. As a result, the number of beacons transmitted per unit time by the providing device (here, device B) is larger than that of other communication devices (here, device A) participating in the network.

  As a result, the search response signal (probe response) from the providing device can be detected in a short time in the providing device search process (steps S510 to S512 in FIG. 5) by the newly participating device C.

  In this way, by increasing the transmission frequency of the beacon of the providing device, when the newly participating device C searches for the providing device, the probability of receiving a search response signal (probe response) from the providing device increases. . Further, even when a newly participating device C searches for a providing device by passive scanning, the probability of receiving a beacon from the providing device increases.

  As a result, it is possible to reduce the probability that the time limit for the communication parameter providing process will elapse without the newly participating device C being able to detect the providing device. Further, if the newly participating device C can detect the providing device in a short time, the time until the communication parameter providing processing is completed can be shortened.

  Returning to FIG. In step S528, the apparatus B broadcasts a start notification message notifying that the communication parameter providing process is started. The start notification message may be unicast transmitted to each communication device participating in the network. In addition, the start notification message can be paraphrased as a message notifying that the device B has started the operation as the providing device.

  In step S529, it is determined whether or not a search signal is received from the device C that is about to newly join the network. If it is determined that the search signal has been received, the search response signal is returned in response to this. It transmits with respect to the apparatus C (step S530).

  Further, the communication device determined as the providing device starts communication parameter providing processing II (step S531). Details of the communication parameter providing process II (step S531) will be described later.

  When the communication parameter providing process II is completed in step S531, the device B resets the CW to the initial value (step S532), returns the beacon transmission frequency increased in step S527 to the original, and ends the notification process. .

  The CW may be reset to the initial value after the start of the communication parameter provision process II, immediately after the start of the process, after the completion of the provision process, or any time after the occurrence of an error.

  When resetting immediately after the start of processing, the frequency (number of times) of beacon transmission is reduced, so that power consumption due to beacon transmission can be more efficiently reduced. The start notification message transmitted in step S528 is repeatedly transmitted until the communication parameter providing process II ends in error or the communication parameter providing process to the receiving apparatus is completed.

  Subsequently, a communication control process in the device C will be described. When the setting button of apparatus B is pressed, apparatus B recognizes this (step S501).

  The device B on which the setting button 106 is pressed is determined not to participate in the network (Yes in step S503), the role is set as a providing device candidate (step S504), and the timer T1 is started (step S505). ). In step S506, beacon transmission is started.

  Furthermore, if the timer T1 has not expired (No in step S507), a search signal is transmitted (step S509), and reception of a search response signal is awaited (step S511). When it is determined that the role of the other communication device (the role of device B) indicated by the information element included in the search response signal is the providing device, the timer T1 is stopped and its role is set to the receiving device ( Steps S513 and S514).

  Furthermore, it joins the network created by the device B, which is the providing device (step S515), and transmits a beacon including an information element indicating that its role is “receiving device” (step S516). The device C participating in the network starts communication parameter reception processing (step S517). Note that details of the communication parameter reception processing have already been described, and a description thereof will be omitted here.

  Next, communication control processing in apparatus A will be described. In the device A, the communication parameter automatic setting process is executed with the device B, and the communication parameter receiving process (step S517) is completed.

  Therefore, in step S518, it is determined whether or not a start notification message has been received from the device B. If a start notification message is received, proxy response processing (step S519) is performed. The detailed flow of the proxy response process (step S519) will be described later.

  By executing the communication control process described above, communication parameters can be easily shared between communication devices.

  As described above, simply by operating the setting button 106 between the devices B and C, the communication connection processing is performed between the devices B and C, and the network B is configured.

  As described above, the communication connection process may be started automatically after the communication parameter providing process is completed, or may be started by pressing the setting button 106 again, inputting a connection command by the input unit 109, or the like. The communication connection process differs depending on the authentication method and the encryption method, which are shared communication parameters.

4.4 Flow of Communication Parameter Providing Process II Next, details of the communication parameter providing process II (step S531) will be described. FIG. 9A is a flowchart showing details of the communication parameter provision processing II (step S531).

  When a communication parameter provision start message is received from the receiving device (Yes in step S901), the providing device starts providing communication parameters (step S902). The communication parameters provided at this time are the network communication parameters created in step S503.

  In step S903, it is determined whether the communication parameter providing process is completed. If it is determined in step S903 that the communication parameter provision processing has been completed, the process proceeds to step S907, and a communication parameter provision completion message is transmitted to the receiving apparatus.

  Further, in step S908, a completion notification message indicating that the communication parameter providing process to the receiving apparatus has been completed is broadcast. Note that the completion notification message may be unicast transmitted to a communication device (here, device A) participating in the network.

  Further, in step S909, a display indicating that the communication parameter automatic setting processing has been successful is performed.

  Specifically, the display unit 105 displays a message on the LCD, and a display indicating that the communication parameter automatic setting processing has succeeded so that the user can identify the LED by blinking, lighting, color, sound, or the like. Do.

  On the other hand, if an error has occurred in step S904, the process proceeds to step S905 to broadcast an error notification message. Note that the error notification message may be unicasted to a communication device (here, device A) participating in the network.

  Furthermore, in step S906, a display indicating that an error has occurred in the communication parameter automatic setting processing is performed.

  Specifically, it indicates that an error has occurred in the communication parameter automatic setting process so that the display unit 105 can display a message on the LCD and the user can identify the LED by blinking, lighting, color, or sound. Display.

4.5 Flow of Proxy Response Processing Next, details of proxy response processing (step S519) will be described. FIG. 9B is a flowchart showing details of the proxy response process (step S519).

  When apparatus A receives the start notification message (Yes in step S518), the proxy response process in FIG. 9B is started.

  When the automatic setting control unit 208 of the device A detects the reception of the start notification message, the automatic setting control unit 208 starts a timer for determining whether or not the time limit for the processing executed in steps S912 to S919 has elapsed (step S911).

  Next, the automatic setting control unit 208 changes the contents of the information element included in the beacon to be transmitted and the search response signal (probe response) (step S912).

  Specifically, the automatic setting control unit 208 adds identification information that uniquely identifies the providing device (device B) to the beacon and search response signal to be transmitted. As the identification information, for example, the MAC address information of the providing device is stored. Thus, even when the device A that is not the providing device returns the search response signal in response to the search signal, the communication device (device C) that is the transmission source of the search signal can detect the presence of the providing device.

  And the beacon control part 213 reduces the transmission frequency (transmission ratio) of a beacon by changing and setting CW to a value larger than an initial value in step S913 (2nd change process).

  As a result, the number of beacons transmitted per unit time by a communication device (device A) other than the providing device participating in the network is smaller than that of the providing device (device B). As a result, the search response signal (probe response) from the providing device can be detected in a short time in the providing device search processing (steps S509 to S512 in FIG. 5) by the newly participating communication device (device C). It becomes.

  Thereafter, the device A waits for a completion notification message or an error notification message transmitted from the providing device (device B) (steps S916 and S917).

  When receiving the notification message, the beacon control unit 213 of the device A resets the CW to the initial value, and restores the beacon transmission frequency reduced in step S913 (step S918).

  Further, the automatic setting control unit 208 returns the contents of the information element included in the beacon and search response signal to be transmitted to the contents before the change performed in step S912 (step S919). That is, the identification information for uniquely identifying the providing device (device B) added to the beacon and search response signal to be transmitted is removed from the beacon and search response signal.

  When the timer set in step S911 expires, the receiving apparatus (apparatus A) stops the processes in steps S912 to S919. If the processing in steps S912 and S913 has already been performed when the timer expires, the same resetting processing as in steps S918 and S919 is performed.

5. Description of Authentication Method and Encryption Method Next, the authentication method and encryption method will be described. In the present embodiment, combinations employed as the authentication method and the encryption method are as shown in FIG. 10, for example.

  Open authentication is an authentication method defined as Open System Authentication in the IEEE 802.11 standard. For details, refer to the IEEE 802.11 standard. Shared authentication is an authentication method defined as Shared Key Authentication in the IEEE802.11 and IEEE802.11i standards, and uses WEP as an encryption method.

  WEP is an abbreviation for Wired Equivalent Privacy. For details, refer to the IEEE802.11 or IEEE802.11i standard. The WPA authentication method, the WPA-PSK authentication method, the WPA2 authentication method, and the WPA2-PSK authentication method are encryption method standards defined by the Wi-Fi Alliance. These are based on RSNA (Robust Security Network Association) in the IEEE 802.11i standard.

  TKIP is an abbreviation for Temporal Key Integrity Protocol. CCMP is an abbreviation for CTRwith CBC-MAC Protocol, and uses AES as an encryption method. AES is an abbreviation for Advanced Encryption Standard.

  For details, refer to the Wi-Fi Alliance specification or test specification. The WPA-PSK authentication method and the WPA2-PSK authentication method are authentication methods using a pre-shared key. The WPA authentication method and the WPA2 authentication method are methods in which user authentication is performed by a separately prepared authentication server and an encryption key for a communication path is acquired from the authentication server. Both refer to the IEEE 802.11i standard for details.

  The communication connection processing method differs depending on the authentication method. As shown in the table, there are six authentication methods that can be used at present, namely, Open authentication, Shared authentication, WPA authentication, WPA-PSK authentication, WPA2 authentication, and WPA2-PSK authentication. Among these, WPA authentication and WPA2 authentication, and WPA-PSK authentication and WPA2-PSK authentication are essentially the same authentication method. Therefore, in the following description, WPA and WPA2 and WPA-PSK and WPA2-PSK are considered to be the same, and four types of authentication methods (OPEN, Shared, WPA, WPA-PSK) will be described.

  However, for WPA authentication, a separate authentication server is installed outside, and authentication processing is performed with the authentication server. Therefore, it is complicated when all communication devices operate in an equal position as in this embodiment. Therefore, the description here is omitted.

  Therefore, in this embodiment, each of Open authentication, Shared authentication, and WPA-PSK authentication will be described.

6). Details of Authentication Method (1) Open Authentication First, open authentication will be described. In the open authentication, the communication parameters shared in the communication parameter automatic setting process are set in each communication device, and the IBSS network is configured by searching each other.

(2) Shared authentication Next, Shared authentication will be described. The detailed description of the shared authentication is described in the specifications of IEEE802.11 and IEEE802.11i and will not be described in detail. However, when executing the shared authentication, it is necessary to determine a requester and a responder.

  In the infrastructure mode, the STA (station) operates as a requester, and the AP (access point) operates as a responder. On the other hand, in the ad hoc mode, there is no AP. Therefore, in order to realize Shared Key Authentication with IBSS, it is necessary to implement a responder function and a requester / responder role determination algorithm in the STA.

  This Requester / Responder role determination algorithm may take the same method as that of the Supplicant / Authenticator role determination in WPA-PSK authentication described later. For example, the communication parameter providing device in the communication parameter automatic setting process may be a responder, and the communication parameter receiving device may be a requester.

(3) WPA-PSK authentication Finally, WPA-PSK authentication will be described. WPA-PSK authentication is standardized by IEEE802.11i and WPA, and the operation method in IBSS is also specified. FIG. 12 shows a sequence defined by IEEE802.11i. For details, refer to the IEEE802.11i standard, and an outline will be described here.

  First, it is assumed that there are devices A and B that have completed the communication parameter automatic setting process. After the communication parameter automatic setting process is completed, the communication connection process is executed using the communication parameter automatically set by the user operation or automatically.

  First, devices A and B search for each other's partner (F1201). If the two devices can recognize each other, the device A and device B having the larger MAC address is the Authenticator, and the other is the Supplicant. Then, the first 4-way handshake and group key handshake are executed (F1202 to F1203).

  The 4-way handshake is a mechanism for exchanging random numbers between the Authenticator and the Supplier and generating a unicast packet encryption key called a pairwise key for each session based on the pre-shared key. The group key handshake is a mechanism for sending a multicast packet or broadcast packet encryption key held by the Authenticator.

  Thereafter, the roles of the Authenticator and the Supplicant are exchanged, and the 4-way handshake and the group key handshake are performed again (F1204 to F1205). As described above, encrypted communication can be performed between the device A and the device B.

7). Method for Improving Processing Time As described above, in full compliance with the IEEE802.11i specification, the 4-way handshake and the group key handshake are performed a plurality of times, so the processing becomes redundant. It takes time to complete the connection because of the redundant processing and the role determination algorithm. Therefore, it is possible to take a technique for reducing redundant processing and improving processing time.

There are several possible methods, but here,
First method: Integration of four-way handshake at once Second method: Integration of group keys into one on the network Third method: Integration of all group keys and pair-wise keys Fourth method: Communication In the parameter automatic setting process, the above four operations including key exchange will be described.

  FIG. 11 shows the difference in the number of key exchange sequences by the above four methods, and the number of pair-wise keys and group keys held.

  First, the number of keys held will be described. In an ad hoc IBSS network composed of n communication devices, if the IEEE 802.11i is fully compliant, n-1 pairwise keys are required for the opposite communication device. In addition to the opposite communication device, two group keys, that is, the current group key and the previous group key, are required, and a total of n + 1 is required. The reason why two own group keys are required is that depending on the progress of the group key handshake, there is a group having different group keys in the same network as a transition period.

  The first method only reduces the sequence and does not change the number of keys it owns.

  In the second method, n-1 pair-wise keys are similarly required, but only one group key may be required.

  In the third method, since the group key is used as it is as a pair-wise key, there are no pair-wise keys and only one group key is held.

  In the fourth method, n-1 pair-wise keys are similarly required. Each group key may be owned or may be one as a whole, so that there may be n + 1 or only one group key depending on circumstances.

  Next, the number of key exchanges performed for each opposing device will be described. When fully compliant with IEEE802.11i, the 4-way handshake is performed twice and the group key handshake is performed twice as described with reference to FIG.

  In the first method, in order to reduce the redundant 4-way handshake, the number of executions of the 4-way handshake is one. The group key handshake remains the same twice.

  In the second method, since the group key is integrated into one in the network, it is always distributed to new terminals, and the group key handshake is performed once. Regarding the number of executions of the 4-way handshake, it may be performed once according to the first method, or may be performed bi-directionally twice according to the IEEE 802.11i standard.

  In the third method, since one preset key is used as a pairwise key and a group key, no key exchange sequence is performed.

  In the fourth method, key exchange processing is performed in the WPS communication parameter automatic setting processing sequence, so that an independent 4-way handshake is not performed. The group key handshake is an arbitrary number of executions.

  As described above with reference to FIG. 11, these methods are advantageous in the number of key exchange sequences and the number of held keys, compared with the method fully compliant with the IEEE802.11i specification described above. .

  Subsequently, the above four methods will be described in detail using sequence diagrams.

7.1 Description of Each Method (1) First Method The first method will be described with reference to FIG.

  First, it is assumed that there are devices A and B that have completed the communication parameter automatic setting process. After the communication parameter automatic setting process is completed, the communication connection process is executed using the communication parameter automatically set by the user operation or automatically.

  First, devices A and B search for each other's partner (F1301). If the two devices can recognize each other, the device A and device B having the larger MAC address is the Authenticator, and the other is the Supplicant. Then, the 4-way handshake and the first group key handshake are executed (F1302 to F1303).

  Thereafter, the roles of the Authenticator and the Supplier are exchanged, and the group key handshake is performed again (F1304). Communication is possible as described above.

  As described above, in the first method, the four-way handshake process performed twice for a set of communication devices in the IEEE802.11i specification is reduced to one time.

  The 4-way handshake is a process for sharing a pair-wise key between communication devices executing the 4-way handshake. Therefore, even if it is performed twice in succession, the security is not improved but only redundant. is there. Therefore, in the first method, the time required for normal communication connection processing can be shortened by reducing the four-way handshake that has been performed twice while changing the conventional direction to one time.

(2) Second Method The second method will be described with reference to FIG. First, it is assumed that there are devices A and B that have completed the communication parameter automatic setting process. After the communication parameter automatic setting process is completed, the communication connection process is executed using the communication parameter automatically set by the user operation or automatically.

  First, apparatus A and apparatus B search for each other (F1401). If they can recognize each other, the device A and device B having the larger MAC address becomes the Authenticator, and the other becomes the Supplicant, and the 4-way handshake and the group key handshake are executed (F1402 to F1403). Communication is possible as described above.

  In the IEEE802.11i specification, different group keys are set for each communication device. However, in the second method, the group keys are integrated into one network.

  A pair-wise key is prepared for each communication path, but a common group key is used as a network. As a result, the group key handshake process, which must be performed twice according to IEEE 802.11i, can be reduced to one time. Also, by setting only one group key, there is an advantage that it is not necessary to maintain a different key for each communication device that has transmitted encryption / decryption processing of broadcast packets and multicast packets, and this is simplified.

(3) Third Method The third method is the same as WPA-None (Optional IBSS Global Pre-Shared Key System) described in Non-Patent Document 2.

  Since the details of WPA-None are described in the above-mentioned literature, the details are omitted. In ordinary WPA, a session key is generated by applying a random number to a source element of a pairwise key by a 4-way handshake. On the other hand, in WPA-None, the element that is the source of the pair-wise key is applied as it is as a session key.

  That is, a major feature of the third method is that no key exchange process is performed. Therefore, the security is lower than the normal WPA connection process in which a session key is generated for each connection. Therefore, when this method is adopted, the security can be improved by starting the communication parameter automatic setting process every connection and randomizing the communication key of the communication parameter shared there every time.

(4) Fourth Method The fourth method will be described with reference to FIG. First, as described in the description of FIG. 4, the search for other communication devices and the determination of the role are performed in the communication parameter automatic setting process (F1501). Subsequently, the communication parameters are transferred from the communication parameter providing apparatus to the communication parameter receiving apparatus by the communication parameter automatic setting process (F1502). In the process of F1502, a key exchange process that has not been conventionally performed is executed simultaneously with the communication parameter providing process.

  Here, in simultaneous execution, a random number used in the message exchange process of the communication parameter providing process is used as a random number of the key exchange process. Therefore, the pair-wise key is shared between apparatus A and apparatus B at the end of F1502. After the communication parameter automatic setting process is completed, a group key exchange process is performed (F1503). Thus, the fourth method is characterized in that key exchange is also performed in the communication parameter automatic setting process.

  According to the fourth method, even if the network is the same, the pairwise keys between the devices are different, so that the security is improved. Also, the total connection time can be shortened by performing a process equivalent to a 4-way handshake in the communication parameter automatic setting process.

  In this description, the group key exchange is separately performed. However, if the group key exchange is performed within the communication parameter automatic setting process, the total connection time can be further shortened.

  In addition to the above-described IEEE802.11i compliant method, any one of the five methods may be selected as a system, and information on which method is used is included in the communication parameters and provided. May be. Further, the switching may be dynamically performed according to the communication parameter automatic setting processing mode.

7.2 Switching of Each Method Here, the case of dynamically switching according to the communication parameter automatic setting processing mode will be described with reference to FIG.

  It is assumed that WPA-PSK or WPA2-PSK that requires key exchange is selected as a communication parameter by the communication parameter automatic setting process. In this case, the key exchange method already used in the network is determined (step S1601). If any key exchange method has already been selected by this determination processing (Yes in step S1601-2), that method is used as it is. If not particularly selected (No in step S1601-2), the processing mode of the communication parameter automatic setting process is subsequently determined (step S1602).

  The processing mode described here includes, for example, whether the communication parameter set by the communication parameter automatic setting process is used permanently or used as temporary session information. For example, if it is a processing mode that permanently uses the set communication parameters (a mode that uses the same communication parameters when wireless communication is performed again after the power is turned off once), a method with high security (first and second) Select the fourth method). And if it is a mode used as temporary session information (a mode in which the communication parameters that have been set are deleted or cannot be used once the power is turned off), a method that prioritizes processing load over security (second, second, etc.) The third method may be selected.

  If it is not determined which key exchange method to use depending on the processing mode (No in step S1602-2), the number of communication devices existing in the same network is subsequently determined (step S1603). A suitable key exchange method is selected according to the number of communication devices. For example, when there are two communication devices, the IEEE 802.11i is fully compliant, or the first method and the fourth method are selected, and when there are three or more communication devices, the second method, Three methods may be selected.

  As described above, according to the present embodiment, when a setting button of a communication apparatus participating in the network is operated, the communication apparatus becomes a providing apparatus and executes communication parameter provision processing. When the operation is started as the providing apparatus, a start notification message is transmitted to another apparatus participating in the network. When the device that has received the start notification message receives a search signal from a device that intends to newly join the network, the device transmits a response signal including information on the device that has started operating as a providing device. In addition, a device that has started operating as a providing device increases the beacon transmission frequency, and a device that has received the start notification message decreases the beacon transmission frequency. For this reason, a device that intends to newly join the network has a higher probability of receiving a beacon or a search response signal from the providing device. As a result, the user can receive communication parameters by selecting an arbitrary communication device without being aware of the providing device and the receiving device from among the communication devices participating in the network.

  That is, it is possible to newly add a communication device to the network by operating a setting button of any communication device without selecting a providing device. Moreover, the power consumption by beacon transmission can be reduced by returning the beacon transmission frequency that has been increased after the providing process is completed. Note that if the beacon transmission frequency is restored immediately after the communication parameter providing process is started, power consumption due to beacon transmission can be more efficiently reduced.

  And after providing communication parameters easily and securely, when adding new to the network, the options for the key exchange algorithm are expanded and automatically determined and set so that the user can Stress can be reduced. In addition, a network can be formed safely, easily and in a short time.

  The preferred embodiment of the present invention has been described above, but this is an example for explaining the present invention, and the scope of the present invention is not limited to this embodiment. The embodiment can be variously modified without departing from the gist of the present invention.

  In each of the above-described embodiments, the example in which the CW value is changed in order to increase the number of beacons transmitted per unit time by the providing device more than other communication devices has been described. However, the present invention is not limited to this, and other parameters may be used as long as the providing device can increase the number of beacon transmissions compared to other communication devices. For example, if the beacon transmission interval (beacon cycle) can be changed, the number of beacon transmissions per unit time can be increased by reducing the beacon transmission interval in the providing device.

  In the above description, it has been described that the change in CW is made larger or smaller than the initial value. Since this change does not necessarily mean that the initial value of CW of each communication device is the same, if the value is changed to the minimum value (CWmin) or the maximum value (CWmax) within the changeable range, the beacon transmission frequency (number of times) Can be changed more reliably. The start notification message has been described as a message notifying that the communication parameter automatic setting process has started.

  However, the start notification message can also be referred to as a message for notifying that the setting button 106 has been operated, and a message for allowing the providing apparatus to provide communication parameters to other receiving apparatuses.

  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 be implemented in other wireless media such as wireless USB, MBOA, Bluetooth (registered trademark), UWB, and ZigBee. Moreover, you may implement in wired communication media, such as wired LAN.

  Here, MBOA is an abbreviation for Multi Band OFDM Alliance. UWB includes wireless USB, wireless 1394, WINET, and the like.

  In addition, the network identifier, the encryption method, the encryption key, the authentication method, and the authentication key are exemplified as communication parameters, but other information may be used, and other information may be included in the communication parameters. Needless to say.

  It goes without saying that the present invention can also be achieved by supplying a system or apparatus with a computer-readable storage medium that records a program code of software that implements the functions of the above-described embodiments. In this case, the above functions are realized by the computer (or CPU or MPU) of the system or apparatus reading and executing the program code stored in the storage medium. In this case, the storage medium storing the program code constitutes the present invention.

  As a storage medium for supplying the program code, for example, a floppy (registered trademark) disk, hard disk, optical disk, magneto-optical disk, CD-ROM, CD-R, magnetic tape, nonvolatile memory card, ROM, or the like is used. be able to.

  Further, the present invention is not limited to the case where the functions of the above-described embodiments are realized by executing the program code read by the computer. For example, an OS (operating system) running on a computer performs part or all of actual processing based on an instruction of the program code, and the functions of the above-described embodiments may be realized by the processing. Needless to say, it is included.

  Furthermore, after the program code read from the storage medium is written in a memory provided in a function expansion board inserted into the computer or a function expansion unit connected to the computer, the functions of the above-described embodiments are realized. Is also included. That is, after the program code is written in the memory, the CPU or the like provided in the function expansion board or function expansion unit performs part or all of the actual processing based on the instruction of the program code, and is realized by the processing. This is also included.

201 providing device 202 communication parameter automatic setting function block 203 packet receiving unit 204 packet transmitting unit 205 search signal transmitting unit 206 search signal receiving unit 207 network control unit 208 automatic setting control unit 209 communication parameter providing unit 210 communication parameter receiving unit 211 role determination Unit 212 Setting Notification Control Unit 213 Beacon Control Unit

Claims (12)

A communication device that operates as a providing device that provides communication parameters for wireless communication or a receiving device that receives communication parameters,
When the user is instructed to start communication parameter setting processing and operates as the providing device, a transmission unit that transmits information indicating the providing device to a participating network;
When operating as the receiving device, in response to a request from another communication device, response means for responding with identification information of the device operating as the providing device;
When the communication parameter providing process is completed, a completion unit that transmits a completion notification to the network;
A communication apparatus comprising: A role determination unit that determines a role of providing communication parameters for wireless communication with another device when the user instructs the start of the communication parameter setting process;
The communication apparatus according to claim 1. In accordance with the start of the operation as the providing device, the communication device further includes changing means for changing a parameter for controlling the transmission of the notification signal so that the number of transmissions of the notification signal per unit time by the communication device increases. ,
The communication apparatus according to claim 1. Further comprising key exchange means for performing an encryption key exchange process upon completion of the communication parameter providing process;
The communication apparatus according to claim 1 or 2, wherein A selection means for selecting a method to be used from a plurality of encryption key exchange processing methods in which at least one of the number of encryption keys and the number of encryption key exchange sequences is different;
The key exchange means performs an exchange process of the method selected by the selection means.
The communication apparatus according to claim 4. The selection means selects a method to be used according to whether or not the provided communication parameter is in a mode for temporarily using.
The communication apparatus according to claim 5. The selecting means selects a method of exchanging encryption keys to be used according to the number of communication devices on the network in which the communication device participates;
The communication device according to claim 5. The wireless communication is a wireless LAN compliant with the IEEE 802.11 series.
The communication device according to claim 1, wherein the communication device is a device. The communication parameter includes at least one of a network identifier, an encryption method, an encryption key, an authentication method, and an authentication key.
The communication apparatus according to claim 1, wherein the communication apparatus is configured as described above.   The response means identifies an apparatus operating as a providing apparatus in response to a request from the other communication apparatus received before receiving a completion notification indicating that the communication parameter providing process has been completed. Respond with information,
  The communication apparatus according to any one of claims 1 to 9, wherein A method for controlling a communication apparatus that operates as a providing apparatus that provides communication parameters for wireless communication or a receiving apparatus that receives communication parameters,
When the transmission unit is instructed by the user to start communication parameter setting processing and operates as the providing device, a transmission step of transmitting information indicating the providing device to a participating network;
When the response means operates as the receiving device, a response step of responding to a request from another communication device with identification information of the device operating as the providing device;
Completion means, when the communication parameter providing process is completed, a completion step of transmitting a completion notification to the network;
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 10 is provided.

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