WO2005013569A1

WO2005013569A1 - Wireless communication system and wireless communication device registration method

Info

Publication number: WO2005013569A1
Application number: PCT/JP2004/010682
Authority: WO
Inventors: Kuniaki Sugimoto; Masaaki Morioka
Original assignee: Matsushita Electric Industrial Co., Ltd.
Priority date: 2003-08-01
Filing date: 2004-07-21
Publication date: 2005-02-10

Abstract

A slave communication device (21) transmits predetermined authentication information to a master communication device (10) when a button (41) is depressed by the user. The master communication device (10) transmits an OK response to a slave communication device (21) which transmitted authentication information received first, and lights up a first LED (32). In response to the OK response, the slave communication device (21) lights up a second LED (42). The two lit up LEDs allow the user to recognize a pair of communication devices targeted for a registration process. Upon confirmation that an LED of a desired slave communication device is lit up, the user depresses a button (31) of the master communication device (10). The master communication device (10) accordingly stores the authentication information, transmits a registration completion notification to the slave communication device (21), and extinguishes the first LED (32).

Description

DESCRIPTION

WIRELESS COMMUNICATION SYSTEM AND WIRELESS COMMUNICATION DEVICE REGISTRATION METHOD

5 TECHNICAL FIELD The present invention relates to a communication system and a communication device registration method. More particularly, the present invention relates to a communication system including a plurality of communication devices connected to each other and0 a method for registering authentication information for establishing a connection between the plurality of communication devices .

BACKGROUND ART5 In a system environment where there are a plurality of communication devices, when a communication device A attempts to communicate with a specific communication device B, a registration process for registering authentication information for establishing a connection between the communication devices A and0 B is performed in order to prevent miscommunication between the communication device A and a communication device other than the communication device B. In this registration process , typically, the authentication information, e.g., a unique address or code for exclusive use between the communication devices A and B, is5 registered to both the communication devices A and B. After the registration process, the authentication information is used in communication. A conventional registration method of the authentication information is described below with respect to an exemplary case where the communication devices are connected via a home network. FIG.19 shows a case where a communication device 120, such as an MD player, is wirelessly connected via Bluetooth to a communication device 110 such as a personal computer. The communication device 120 is previously provided with authentication information 130 for device identification which is a so-called personal identification number (PIN) code standardized by Bluetooth. FIG. 20 shows an exemplary PIN code including eight octets each represented by hexadecimal digits . The user uses a keyboard or the like to input and register the authentication information 130 of the communication device 120 to the communication device 110. Once the authentication information 130 is registered, the communication device 110 notifies the communication device 120 of the completion of registration. Thus, the authentication information 130 is used in subsequent communication. In the above conventional registration method, however, at least one communication device is required to have a user interface (e.g. , a keyboard) for inputting the authentication information. Moreover, as in the above example, if the authentication information is a 16-digit long PIN code consisting of a combination of numbers and symbols, it is troublesome to correctly input the authentication information. For example, Japanese Laid-Open Patent Publication No. 2002-374261 suggests a conventional technique which does not require a troublesome input operation. Specifically, in the conventional technique suggested by Japanese Laid-Open Patent Publication No. 2002-374261, communication devices each are providedwithanauthenticationbutton, andauthenticationbuttons of two communication devices between which a connection is desired to be established are simultaneously depressed and released. If there are two communication devices having their authentication buttons depressed for a time period within a predetermined range, the two communication devices are considered as a pair of devices between which a connection is desired to be established. In the above-described conventional technique, communication devices to be connected are specified by depressing their respective authentication buttons , and thereafter a registration process is automatically implemented between the specified communication devices. Accordingly, for example, if an authentication button of a communication device other than the communication devices to be connected is depressed by mistake, the user is not able to know between which communication devices the registration process is implemented. Therefore, in the above-described conventional technique, there is a problem that the registration process might be implemented between communication devices which are not desired to be connected. Thus, an object of the present invention is to provide a communication system and a communication device registration method which allow the user to recognize two communication devices specified to be connected to each other before a registration process is implemented.

DISCLOSURE OF THE INVENTION The present invention is directed to a communication system in which a master communication device operable to entirely manage the communication system is connected to at least one slave communication device. To achieve the above object, the slave communication device of the communication system according to the present invention includes : afirst registration start instruction unit; a transmission unit ; a reception unit; a first notification unit; and a control unit. The master communication device includes: a reception unit; a second notification unit; a transmission unit; a registration completion instruction unit; and a control unit . In the slave communication device, the first registration start instruction unit provides an instruction to start a registration process with the master communication device. The transmission unit transmits predetermined authentication information to the master communication device based on the instruction provided by the first registration start instruction unit . The reception unit receives a reception result of the authentication information from the master communication device. The first notification unit provides a user with the reception result. The control unit performs the registration process based on a notification from the first notification unit . In the master communication device, the reception unit receives the authentication information from the at least one slave communication device. The second notification unit provides the user with the reception result of the authentication information. The transmission unit transmits a reception success response to a slave communication device having transmitted first received authentication information. The registration completion instruction unit provides an instruction to register a desired slave communication device to which the reception success response has been transmitted. The control unit performs the registration process based on the instruction provided by the registration completion instruction unit . Typically, the first registration start instruction unit is an operating button which is depressed by the user to provide an instruction to start the registration process . Alternatively, the first registration start instruction unit provides an instruction to start the registration process when the at least one slave communication device is turned on. The registration completion instruction unit is an operating button which is depressed by the user to provide an instruction to implement the registration process. The master communication device may further include a registration rejection instruction unit. The registration rejection instruction unit provides an instruction toreject theregistrationprocess so as not toregisteranundesired slave communication device to which the reception success response has been transmitted. The^'control unit rejects the registration process based on the instruction provided by the registration rejection instruction unit. The registration rejection instruction unit is an operating button which is depressed by the user to provide an instruction to reject the registration process . Alternatively, the registration rejection instruction unit provides an instruction to reject the registration process if the registration completion instruction unit does not provide any instruction before a lapse of a predetermined time period since the reception result is provided by the second notification unit . Note that it is preferable that the first and second notification units are LEDs which are lit up to provide the reception result to the user. In the case where the master communication device further includes a second registration start instruction unit operable to provide an instruction to start a registration process with the at least one slave communication device, it is possible to allow the reception unit of the master communication device to receive the authentication information from the at least one slave communication device after the instruction is provided by the second registration start instruction unit. Typically, the second registration start instruction unit is an operating button which is depressed by the user to provide an instruction to start the registration process. In the case where the slave communication device further includes an authentication information generation unit operable to generate the authentication information on a random basis , it is possible to allow the transmission unit of the slave communication device to transmit the authentication information generated by the authentication information generation unit to the master communication device. Processes performed by elements of the above-described communication devices can be construed as constituting a series ofprocessprocedures of acommunicationdeviceregistrationmethod. Specifically, the method includes the steps of: providing an instruction to start a registration process with the master communication device; transmitting predetermined authentication information from the slave communication device to the master communication device based on the instruction to start the registration process; causing the slave communication device to receive the reception result of the authentication information from the master communication device; providing, from the slave communication device, a user with the reception result; causing the slave communication device to perform the registration process based on the reception result; causing the master communication device to receive the authentication information from the slave communication device; providing, from the master communication device, the user with the reception result; causing the master communication device to transmit a reception success response to the slave communication device if the authentication information from the slave communication device reaches the master communication device first, and to transmit a reception failure response to the slave communication device if the authentication information from the slave communication device reaches the master communication device later than authentication information from another slave communication device; providing, from the master communication device, an instruction to complete the registration process so as to register a desired slave communication device to which the reception success response has been transmitted; and causingthemastercommunicationdevice toperformtheregistration process based on the instruction to complete the registration process or the instruction to reject the registration process. The above-described communication device registration method is provided in the form of a program code causing a computer to implement the series of process procedures. The program code may be introduced to a computer in the form of a computer-readable storage medium having the program code installed therein. In the present invention, as described above, the authentication information is transferred by communication from the slave communication device to the master communication device, and therefore it is possible to eliminate the user's need to input complicated authentication' information, thereby making it possible for the user to readily perform the registration process . Moreover, the user is allowed to recognize a communication device targeted for a registration process , and the registration process of the communication device is implemented after the user's recognition. Thus , it is ensured that the user registers a desired communication device. Further, the registration process is not supposed to start unless two communication devices between which a connection is desired to be established provide instructions. Accordingly, it is possible to further increase the reliability and safety in establishing a connection. Furthermore, the authentication information used for registration is generated on a random basis at the time of a registration process, and therefore it is possible to change the authentication information for eachregistrationprocess , thereby reducing the possibility that the authentication information is known and misused by the third party.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram showing a structure of a communication system according to a first embodiment of the present invention; FIG. 2 is a block diagram showing a detailed structure of each of a master communication device and a slave communication device shown in FIG. 1; FIG.3 is aflowchart showing the procedure of acommunication device registration performed by slave communication devices 21 through 2N; FIG.4 is aflowchart showing the procedure of a communication device registration performed by the master communication device; FIG. 5A is a sequence chart showing a case where the slave communication device is correctly registered in accordance with the procedures shown in FIGs. 3 and 4; FIG. 5B is a sequence chart showing a case where the slave communication device is not correctly registered as set by the procedures shown in FIGs. 3 and 4; FIG. 6 is a diagram showing a structure of a communication system according to a second embodiment of the present invention; FIG. 7 is a block diagram showing a detailed structure of each of a master communication device and a slave communication device shown in FIG. 6; FIG.8 is aflowchart showing the procedure of acommunication device registration performed by the master communication device; FIG. 9A is a sequence chart showing a case where the slave communication device is correctly registered in accordance with the procedures shown in FIGs. 3 and 8; FIG. 9B is a sequence chart showing a case where the slave communication device is not correctly registered as set by the procedures shown in FIGs. 3 and 8; FIG. 10 is a diagram showing a structure of a communication system according to a third embodiment of the present invention; FIG. 11 is a block diagram showing a detailed structure of each of a master communication device and a slave communication device shown in FIG. 10; FIG. 12 is a flowchart showing the procedure of a communication device registration performed by slave communication devices 61 through 6N; FIG. 13A is a sequence chart showing a case where the slave communication device is correctly registered in accordance with the procedures shown in FIGs. 4 and 12; FIG. 13B is a sequence chart showing a case where the slave communication device is not correctly registered as set by the procedures shown in FIGs. 4 and 12; FIG. 14 is a diagram showing a structure of a communication system according to a fourth embodiment of the present invention; FIG. 15 is a block diagram showing a detailed structure of each of a master communication device and a slave communication device shown in FIG. 14; FIG. 16A is a sequence chart showing a case where the slave communication device is correctly registered in accordance with the procedures shown in FIGs. 8 and 12; FIG. 16B is a sequence chart showing a case where the slave communication device is not correctly registered as set by the procedures shown in FIGs. 8 and 12; FIG. 17 is a block diagram showing a detailed structure of a variation of a slave communication device; FIG.18 is a sequence diagram showing avariation of aprocess procedure implemented by a communication system of the present invention; FIG. 19 is a diagram used for explaining a conventional communication device registration method; and FIG. 20 is a diagram showing an exemplary PIN code.

BEST MODE FOR CARRYING OUT THE INVENTION The present invention provides a communication system and acommunicationdeviceregistrationmethodwhichare advantageous , particularly, in a case where a plurality of communication devices having no user interface are connected by radio communication. Hereinafter, embodiments of the present invention are described with respect to an exemplary security communication system using a home network established by Bluetooth. (First Embodiment ) FIG. 1 is a diagram showing a structure of a communication system according to a first embodiment of the present invention. In FIG. 1, the communication system according to the first embodiment includes amastercommunicationdevice 10 , whichmanages the entire system, and slave communication devices 21 through 2N. The master communication device 10 and the slave communication devices 21 through 2N are connected by radio communication. The slave communication devices 21 through 2N each are, for example, a small security sensorwhich does not have a complex user interface such as a keyboard. The slave communication devices 21 through 2N are typically provided on a window or a door of a house, and operable to, responsive to vibration or closing/opening of the window or door, transmit a predeterminedradio signal to the master communication device 10. The master communication device 10 is operable to collectively manage communication with the slave communication devices 21 through 2N. Specifically, the master communication device 10 receives and analyzes any predetermined radio signal transmitted from the communication devices 21 through 2N, and performs a predetermined process, e.g., a report to a security company. FIG. 2 is a block diagram showing a detailed structure of each of the master communication device and a slave communication device shown in FIG.1. In FIG.2 , the master communication device 10 includes: a registration completion instruction unit 31; a second notification unit 32; a control unit 33; a transmission/reception unit 34; a storage unit 35; and a registration rejection instruction unit 37. Each of the slave communication devices 21 through 2N includes : a registration start instruction unit 41; a first notification unit 42; a control unit

43; a transmission/reception unit 44; and a storage unit 45. In the master communication unit 10, the registration completion instruction unit 31 is typically an operating button which is used by the user to input an instruction to complete a registration operation. For ease of understanding, the registration completion instruction unit 31 is referred to below as a "registration completionbutton 31" . The secondnotification unit 32 is typically an LED which is used for notifying the user that any authentication information (in this example, a PIN code) from the slave communication devices 21 through 2N is successfully received. For ease of understanding, the secondnotificationunit 32 is referred to below as a "second LED 32". The transmission/reception unit 34 is operable to transmit/receive apredeterminedsignal (containing adataframe andacontrol frame) to/from the slave communication devices 21 through 2N. Specifically, the predetermine signal is a discovery request/response, a connection request/response, a registration completion notification, or authentication information. The storage unit 35 is operable to store registered authentication information. The registration rejection instruction unit 37 is typically an operating button which is used by the user to input an instruction to reject a registration process. For ease of understanding, the registration rejection instruction unit 37 is referred to below as a "registration rejection button 37". The control unit 33 is operable to control the entire communication device 10. In each of the slave communication devices 21 through 2N, the registration start instruction unit 41 is typically an operating button which is used by the user to input an instruction to start a registration. For ease of understanding, the registration start instruction unit 41 is referred to below as a "registration start button 41". The first notification unit 42 is typically an LED which is used for notifying the user that any authentication information (in this example, a PIN code) is successfully transmitted to the master communication device 10. For ease of understanding, the first notification unit 42 is referred to below as a "first LED 42" . The transmission/reception unit 44 is operable to transmit/receive a predetermined signal, e.g. , adiscoveryrequest/response, a connection request/response, a registration completion notification, or authentication information, to/from the master communication device 10. The storage unit 45 has stored therein authentication information to be transmitted to the master communication device 10. The control unit 43 is operable to control the entire slave communication device. Hereinbelow, a communication device registration method implemented by the communication system according to the first embodiment as configured above is describedwithreference to FIGs . 3, 4, 5A, and 5B. In the following descriptions of the communication device registrationmethod, the slave communication device 21 is targeted for registration, and the slave communication device 22 is not targeted for registration but is operated by deliberate intension or by mistake. FIG.3 is a flowchart showing the procedure of a communication device registration performed by the slave communication devices 21 through 2N. FIG. 4 is a flowchart showing the procedure of a communication device registration performed by the master communication device. FIG. 5A is a sequence chart showing a case where the slave communication device is correctly registered in accordance with the procedures shown in FIGs. 3 and 4. FIG. 5B is a sequence chart showing a case where the slave communication device is not correctly registered as set by the procedures shown in FIGs. 3 and 4. When the user depresses the registration start button 41, the slave communication device 21 targeted for registration starts a communication device registration process as shown in FIG. 3, and transmits a discovery request to discover an access point, i.e. , the master communication device 10 (step S301) . Similarly, the slave communication device 22, which is not targeted for registration, starts a communication device registration process as shown in FIG.3 when the user depresses the registration start button 41 thereof, and then transmits a discovery request to discover the master communication device 10 (step S301). Upon receipt of the discovery requests from each of the slave communication devices 21 and 22, the master communication device 10 starts a communication device registration process shown in FIG. 4, and transmits a discovery response to each of the communication devices 21 and 22 (step S401) . Upon receipt of the discovery response from the communication device 10 (Yes in step S302) , each of the slave communication devices 21 and 22 transmits a connection request to the master communication device 10 (step S303). Upon receipt of the connection request from each of the slave communication devices 21 and 22 (Yes in step S402) , the master communication device 10 transmits a connection response to each of the slave communication devices 21 and 22 (step S403). Upon receipt of the connection response from the master communication device 10 (Yes in step S304), each of the slave communication devices 21 and 22 transmits authentication information prestored in the respective storage unit 45 to the master communication device 10 (step S305). The master communication device 10 receives the authentication information from each of the slave communication devices 21 and 22 ( step S404 ) . The master communication device 10 transmits an OK response to one of the slave communication devices 21 and 22 whose authentication information has reached the master communication device 10 first, and transmits an NG response to the other slave communication device (step S405). At the same time, the master communication device 10 lights up the second LED 32 (step S406) . The slave communication device having received the OK response lights up the first LED 42 (steps S306 and S307) . Thus, the two LEDs lit up by the above processing allow the user to recognize which communication devices are targeted for a registration process . If the user recognizes that the two communication devices having their LEDs lit up are the master communication device 10 and the slave communication device 21 between which a connection is desired to be established, the user depresses the registration completion button 31 of the master communication device 10 (Yes in step S407) . In response to the depression of the registration completion button 31 , the master communication device 10 registers the slave communication device 21 by storing the authentication information received therefrom to the storage unit 35 ( step S409 ) . Thereafter, the communication device 10 transmits a registration completion notification to the slave communication device 21 ( step S410), andextinguishes the secondLED 32 (stepS411) . Uponreceipt of the registration completion notification from the master communication device 10 (Yes in step S308 ) , the slave communication device 21 extinguishes the first LED 42 (step S310). Thus, the registration process is normally completed. On the other hand, if the user recognizes that the two communication devices having their LEDs lit up are the master communication device 10 and the slave communication device 22 between which a connection is not desired to be established, the user depresses the registration rejection button 37 of the master communication device 10 (Yes in step S408). In response to the depression of the registration rejection button 37, the master communication device 10 transmits a registration rejection notification to the slave communication device 22 (step S412), and extinguishes the second LED 32 (step S413) . Upon receipt of the registration rejection notification from the master communication device 10 (Yes in step S309 ) , the slave communication device 22 extinguishes the first LED 42 (step S311). Thus, the registration process is normallyterminatedwithout registration . Note that the registration process is terminated before completion in either of the following cases : where the slave communication device 21 or 22 does not receive the discovery response in step S302; where the master communication device JO does not receive the connection request in step S402; where the slave communication device 21 or 22 does not receive the connection response in step S304; where the master communication device 10 does not receive the authentication information in step S404 ; where the slave communication device 21 or 22 does not receive the OK response; where the slave communication device 21 or 22 does not receive the registration completion notification and the registration rejection notification in steps S308 and S309; and where the registration completion button 31 and the registration rejection button 37 of the master communication device 10 are not depressed in step S407 and S408. Note that if neither the registration rejection button 37 nor the registration completion button 31 is depressed at a predetermined timing, the same process as that performed in the case of depressing the registration rejection button 37 may be performed. As described above, in the communication system and the communication device registration method according to the first embodiment of the present invention, the authentication information is transferre by communication from the slave communication device to the master communication device, and therefore it is possible to eliminate the user's need to input complicated authentication information, thereby making it possible for the user to readily perform the registration process . Moreover, the LEDs are lit up so as to allow the user to recognize whichcommunicationdevices are targetedforaregistrationprocess , thereby providing the user with an opportunity to make a terminal decision about communication device registration. Thus, it is ensuredthat the user registers only adesired communication device without registering a communication device which is not desired to be registered. Note that if an LED of the desired communication device is not lit up, the above-described processes for the discovery request and response and the connection request and response are repeatedly performed until the LED of the desired communication device is lit up. (Second Embodiment) In the above-described first embodiment, the registration process is started when the user depresses the registration start button 41 of a slave communication device. Accordingly, themaster communication device 10 is not able to know when the registration process is started. Therefore, the master communication device 10 is required to be always kept in such a state as to be able to receive any discovery request from the slave communication devices 21 through 2N. In a second embodiment of the present invention, the registration start button is also provided to the master communication device 10 such that aregistration process is started when the registration start button of each of the master communication device 10 and a slave communication device targeted for registration is depressed. The details of atechnique employed by the second embodiment is described below. FIG. 6 is a diagram showing a structure of a communication systemaccording to the second embodiment of the present invention. As is apparent from FIG. 6, the communication system according to the second embodiment is different from the communication system according to the first embodiment in that the master communication device 10 is replaced by a master communication device 50. Hereinbelow, the secondembodiment is describedmainlywithrespect to differences from the first embodiment . Note that in the second embodiment, elements similar to those described in the first embodiment are denoted by the same reference numerals . FIG. 7 is a block diagram showing a detailed structure of each of the master communication device and a slave communication device shown in FIG.6. In FIG.7, the master communication device 50 includes: the registration completion instruction unit 31; the second notification unit 32; the control unit 33; the transmission/reception unit 34; the storage unit 35; a second registration start instruction unit 36; and the registration rejection instruction unit 37. The second registration start instruction unit 36 is typically an operating button which is used, in conjunction with the registration start button 41 of a slave communication device targeted for registration, by the user to input an instruction to start a registration process. For ease of understanding, the second registration start instruction unit 36 is referred to below as a "registration start button 36". Hereinbelow, a communication device registration method implemented by the communication system as configured above according to the second embodiment is described with reference to FIGs. 3, 8, 9A, and 9B. In the following descriptions of the communication device registrationmethod, the slave communication device 21 is targeted for registration, and the slave communication device 22 is not targeted for registration but is operated by deliberate intension or by mistake. FIG.8 is a flowchart showing the procedure of a communication device registration performed by the master communication device. FIG. 9A is a sequence chart showing a case where the slave communication device is correctly registered in accordance with the procedures shown in FIGs. 3 and 8. FIG. 9B is a sequence chart showing a case where the slave communication device 21 is not correctly registered as set by the procedures shown in FIGs . 3 and 8. If the user depresses the registration start buttons 41 of the slave communication devices 21 and 22 and the registration start button 36 of the master communication device 50, the slave communication devices 21 and 22 start a communication device registration process as shown in FIG. 3, and the master communication device 50 starts the communication device registration process shown in FIG. 8. Once the communication device registration process is started, each of the slave communication devices 21 and 22 transmits a discovery request to the master communication device 50 (step S301) . Upon receipt of the discovery request from each of the slave communication devices 21 and 22 (Yes in step S801), the master communication device 50 transmits a discoveryresponse to each of the communication devices 21 and 22 (step S802). Upon receipt of the discovery response from the master communication device 50 (Yes in step S302), each of the slave communication devices 21 and 22 transmits a connection request to the master communication device 50 (step S303) . Upon receipt of the connection request from each of the slave communication devices 21 and 22 (Yes in step S803), the master communication device 50 transmits a connection response to each of the slave communication devices 21 and 22 (step S804). Upon receipt of the connection response from the master communication device 50 (Yes in step S304), each of the slave communication devices 21 and 22 transmits authentication information prestored in the storage unit 45 to the master communication device 50 (step S305). The master communication device 50 receives the authentication information from each of the slave communication devices 21 and 22 (step S805) . The master communication device 50 transmits an OK response to one of the slave communication devices 21 and 22 whose authentication information has reached the master communication device 10 first, andtransmits anNGresponse to the other slave communication device (step S806). At the same time, the master communication device 50 lights up the secondLED 32 (step S807) . The slave communication device having received the OK response lights up the first LED 42 (steps S306 and S307) . Thus, the two LEDs lit up by the above processing allow the user to recognize which communication devices are targeted for a registration process. If the user recognizes that the two communication devices having their LEDs lit up are the master communication device 50 and the slave communication device 21 between which a connection is desired to be established, the user depresses the registration completion button 31 of the master communication device 50 (Yes in step S808) . In response to the depression of the registration completion button 31 , the master communication device 50 registers the slave communication device 21 by storing the authentication information received from the slave communication device 21 to the storage unit 35 (step S810). Thereafter, the communication device 50 transmits a registration completion notification to the slave communication device 21 (step S811), and extinguishes the second LED 32 (step S812). Upon receipt of the registration completion notification from the master communication device 50 (Yes in step S308) , the slave communication device 21 extinguishes the first LED 42 (step S310). Thus, the registration process is normally completed. If the user recognizes that the two communication devices having their LEDs lit up are the master communication device 50 and the slave communication device 22 between which a connection is not desired to be established, the user depresses the registrationrejectionbutton 37 of themastercommunicationdevice 50 (Yes in step S809). In response to the depression of the registration rejection button 37 , the master communication device 50 transmits a registration rejection notification to the slave communication device 22 (step S813) , and extinguishes the second LED 32 (step S814). Upon receipt of the registration rejection notification from the master communication device 50 (Yes in step S309), the slave communication device 22 extinguishes the first LED 42 (step S311). Thus, the registration process is normally terminated without registration. Note that the registration process is terminated before completion in either of the following cases : where the slave communication device 21 or 22 does not receive the discovery response in step S302; where the master communication device 50 does not receive the connection request in step S803; where the slave communication device 21 or 22 does not receive the connection response in step S304; where the master communication device 50 does not receive the authentication information in step S805 ; where the slave communication device 21 or 22 does not receive the OK response in step S306; where the slave communication device 21 or 22 does not receive the registration completion notification and the registration rejection notification in steps S308 and S309 ; and where the registration completion button 31 and the registrationrejectionbutton 37 of themastercommunicationdevice 50 are not depressed in step S808 and S809. As described above, in the communication system and the communication device registration method according to the second embodiment of the present invention, the registration process cannot be started unless registration start buttons of two communication devices between which a connection is desired to establishedare depressed. Accordingly, it is possible to further increase the reliability and safety in establishing a connection. (Third Embodiment ) The first embodiment has been described with respect to a case where each of the slave communication devices 21 through 2N has fixed authentication information stored therein. However, in such a case, the fixed authentication information might be misused if it is known by a third party. In a third embodiment of the present invention, each of the slave communication devices 21 through 2N is not provided with fixed authentication information, and a connection between the master communication device 10 and each of the slave communication devices 21 through 2N is established using authentication informationwhich is randomlyprovidedat the time of aregistration process . FIG.10 is a diagram showing a structure of a communication system according to the third embodiment of the present invention. As is apparent from FIG. 10, the communication system according to the third embodiment is different from the communication system according to the first embodiment in that the slave communication devices 21 through 2N are replaced by slave communication devices 61 through 6N. Hereinbelow, the third embodiment is described mainlywithrespect to differences fromthe first embodiment . Note that in the third embodiment, elements similar to those described in the first embodiment are denoted by the same reference numerals . FIG. 11 is a block diagram showing a detailed structure of each of the master communication device and a slave communication device shown inFIG.10. In FIG.11, the slave communication device includes: the registration start instruction unit 41; the first notification unit 42; the control unit 43; the transmission/reception unit 44; the storage unit 46; and an authentication information generation unit 47. The authentication information generation unit 47 is operable to generate authentication informationtobe transmittedto themaster communication device 10 on a random basis at the time of a registration process. The storage unit 46 is operable to store the authentication information generated by the authentication information generation unit 47 upon receipt of a registration completion notification from the master communication device 10. Hereinbelow, a communication device registration method implemented by the communication system as configured above according to the third embodiment is described with reference to FIGs. 4, 12, 13A, and 13B. In the following descriptions of the communication device registrationmethod, the slave communication device 61 is targeted for registration, and the slave communication device 62 is not targeted for registration but is operated by deliberate intension or bymistake . FIG.12 is a flowchart showing the procedure of a communication device registration performed by the slave communication devices 61 through 6N. FIG. 13A is asequence chart showingacasewhere the slave communicationdevice is correctly registered in accordance with the procedures shown in FIGs. 4 and 12. FIG. 13B is a sequence chart showing a case where the slave communication device is not correctly registered as defined by the procedures shown in FIGs. 4 and 12. When the user depresses the registration start button 41 of the slave communication device 61 targeted for registration, the slave communication device 61 starts a communication device registration process as shown in FIG.12 , and transmits a discovery request to discover an access point , i.e., themaster communication device 10 (stepS1201) . Similarly, the slave communication device 62, which is not targeted for registration, starts a communication device registration process as shown in FIG. 12 when the user depresses the registration start button 41 thereof, and then transmits a discovery request to discover the master communication device 10 (step S1201). Upon receipt of the discovery requests from each of the slave communication devices 61 and 62, the master communication device 10 starts acommunicationdeviceregistration process shown in FIG. 4, and transmits a discovery response to each of the communication devices 61 and 62 (step S401). Upon receipt of the discovery response from the communication device 10 (Yes in step S1202), each of the slave communication devices 61 and 62 transmits aconnection request to themaster communication device 10 (step S1203). Upon receipt of the connection request from each of the slave communication devices 61 and 62 (Yes in step S402), the master communication device 10 transmits a connection response to each of the slave communication devices 61 and 62 (step S403) . Upon receipt of the connection response from the master communication device 10 (Yes in step S1204), the authentication information generation unit 47 of each of the slave communication devices 61 and 62 generates authentication information on a random basis, and each of the slave communication devices 61 and 62 transmits the generated authentication information to the master communication device 10 (steps S1205 and S1206). The master communication device 10 receives the authentication information from each of the slave communication devices 61 and 62 (step S404) . The master communication device 10 transmits an OK response to one of the slave communication devices 61 and 62 whose authentication information has reached the master communication device 10 first, and transmits an NG response to the other slave communication device (step S405). At the same time, the master communication device 10 lights up the second LED 32 (step S406) . The slave communication device having received the OK response lights up the first LED 42 (steps S1207 and S1208). Thus, the two LEDs lit up by the above processing allow the user to recognize which communication devices are targeted for a registration process. If the user recognizes that the two communication devices having their LEDs lit up are the master communication device 10 and the slave communication device 61 between which a connection is desired to be established, the user depresses the registration completion button 31 of the master communication device 10 (Yes in step S407) . In response to the depression of the registration completion button 31 , the master communication device 10 registers the slave communication device 61 by storing the authentication information received from the slave communication device 61 to the storage unit 35 (step S409). Thereafter, the communication device 10 transmits a registration completion notification to the slave communication device 61 (step S410), and extinguishes the second LED 32 (step S411). Upon receipt of the registration completion notification from the master communication device 10 (Yes in step S1209) , the slave communication device 61 stores the authentication information generated by the authentication information generation unit 47 to the storage unit 46 (step S1211.) . At the same time, the slave communication device 61 extinguishes the first LED 42 (step S1212). Thus, the registration process is normally completed. If the user recognizes that the two communication devices having their LEDs lit up are the master communication device 10 and the slave communication device 62 between which a connection is not desired to be established, the user depresses the registrationrejectionbutton 37 of themastercommunicationdevice 10 (Yes in step S408). In response to the depression of the registration rejection button 37 , the master communication device 10 transmits a registration rejection notification to the slave communication device 62 (step S412), and extinguishes the second LED 32 (step S413). Upon receipt of the registration rejection notification from the master communication device 10 (Yes in step S1210) , the slave communication device 62 extinguishes the first LED 42 (step S1213) . Thus, the registration process is normally terminated without causing any error. Note that the registration process is terminated before completion in either of the following cases : where the slave communication device 61 or 62 does not receive the discovery response in step S1202; where the master communication device 10 does not receive the connection request in step S402; where the slave communication device 61 or 62 does not receive the connection response in step S1204; where the master communication device 10 does not receive the authentication information in step S404 ; where the slave communication device 61 or 62 does not receive the OK response in step S1207; where the slave communication device 61 or 62 does not receive the registration completion notification and the registration rejection notification in steps S1209 and S1210; and where the registration completion button 31 and the registrationrejectionbutton 37 of themastercommunicationdevice 10 are not depressed in step S407 and S408. As described above, in the communication system and t.he communication device registration method according to the third embodiment of the present invention, the authentication information used for registration is generated on a random basis at the time of a registration process. This allows the authentication information to be changed for each registration process , thereby reducing the possibility that the authentication information is known and misused by the third party. (Fourth Embodiment) In the above-described first embodiment, the registration process is started when the user depresses the registration start button 41 of any one of the slave communication devices 21 through 2N. Accordingly, the master communication device 10 is not able to know when the registration process is started. Therefore, the master communication device 10 is required to be always kept in such a state as to be able to receive any discovery request from the slave communication devices 21 through 2N. Moreover, in the first embodiment, each of the slave communication devices 21 through 2N has fixed authentication information stored therein. However, in such a case, the fixedauthentication informationmight be misused if it is known by a third party. In a fourth embodiment of the present invention, the registration start button is also provided to the master communication device 10 such that aregistration process is started when the registration start button of each of the master communication device 10 and a slave communication device targeted for registration is depressed. Moreover, each of the slave communication devices 21 through 2N is not provided with fixed authentication information, and a connection between the master communication device 10 and each of the slave communication devices 21 through2Nis establishedusingauthentication informationwhich is randomly provided at the time of a registration process. FIG. 14 is a diagram showing a structure of a communication system according to the fourth embodiment of the present invention . FIG. 15 is a block diagram showing a detailed structure of each of themaster communication device and a slave communication device shown in FIG. 14. As is apparent from FIGs. 14 and 15, the communication system according to the fourth embodiment includes a combination of the master communication device 50 of the communication system according to the second embodiment and the slave communication devices 61 through 6N according to the third embodiment. Hereinbelow, the fourth embodiment is described mainly with respect to differences from the first through third embodiments . Note that in the fourth embodiment , elements similar to thosedescribedinthe first throughthirdembodiment are denoted by the same reference numerals . Hereinbelow, a communication device registration method implemented by the communication system as configured above according to the fourth embodiment is described with reference to FIGs. 8, 12, 16A and 16B. In the following descriptions of the communication device registration method, the slave communication device 61 is targeted for registration, and the slave communication device 62 is not targeted for registration but is operated by deliberate intension or by mistake. FIG. 16A is a sequence chart showing a case where the slave communication device is correctly registered in accordance with the procedures shown in FIGs. 8 and 12. FIG. 16B is a sequence chart showing a case where the slave communication device is not correctly registered as defined by the procedures shown in FIGs. 8 and 12. When the user depresses the registration start buttons 41 of the slave communication devices 61 and 62 and the registration start button 36 of the master communication device 50, the slave communication devices 61 and 62 start a communication device registration process as shown in FIG. 12, and the master communication device 50 starts the communication device registrationprocess shown inFIG.8. Inresponse to thedepression of the registration start button 41 , eachof the slave communication devices 61 and 62 transmits a discovery request to the master communication device 50 (step S1201). Upon receipt of the discovery request from each of the slave communication devices 61 and 62 (Yes in step S801), the master communication device 50 transmits a discoveryresponse to each of the communication devices 61 and 62 (step S802). Upon receipt of the discovery response from the master communication device 50 (Yes in step S1202) , each of the slave communication devices 61 and 62 transmits a connection request to the master communication device 50 (step S1203) . Up.on receipt of the connection request from each of the slave communication devices 61 and 62 (Yes in step S803), the master communication device 50 transmits a connection response to each of the slave communication devices 61 and 62 (step S804). Upon receipt of the connection response from the master communication device 50 (Yes in step S1204), the authentication information generation unit 47 of each of the slave communication devices 61 and 62 generates authentication information on a random basis, and each of the slave communication devices 61 and 62 transmits the generated authentication information to the master communication device 50 (steps S1205 and S1206). The master communication device 50 receives the authentication information from each of the slave communication devices 61 and 62 (step S805) . The master communication device 50 transmits an OK response to one of the slave communication devices 61 and 62 whose authentication information has reached the master communication device 50 first, and transmits an NG response to the other slave communication device (step S806). At the same time, the master communication device 50 lights up the second LED 32 (step S807) . The slave communication device having received the OK response lights up the first LED 42 (steps S1207 and S1208). Thus, the two LEDs lit up by the above processing allow the user to recognize which communication devices are targeted for a registration process . If the user recognizes that the two communication devices having their LEDs lit up are the master communication device 50 and the slave communication device 61 between which a connection is desired to be established, the user depresses the registration completion button 31 of the master communication device 50 (Yes in step S808) . In response to the depression of the registration completion button 31 , the master communication device 50 registers the slave communication device 61 by storing the authentication information received from the slave communication device 61 to the storage unit 35 (step S810). Thereafter, the communication device 50 transmits a registration completion notification to the slave communication device 61 (step S811), and extinguishes the second LED 32 (step S812). Upon receipt of the registration completion notification from the master communication device 50 (Yes in step S1209) , the slave communication device 61 stores the authentication information generated by the authentication information generation unit 47 to the storage unit 46 ( step S1211 ) . At the same time, the slave communication device 61 extinguishes the first LED 42 (step S1212). Thus, the registration process is normally completed. If the user recognizes that the two communication devices having their LEDs lit up are the master communication device 50 and the slave communication device 62 between which a connection is not desired to be established, the user depresses the registrationrejeσtionbutton 37 of themastercommunicationdevice 50 (Yes in step S809). In response to the depression of the registration rejection button 37 , the master communication device 50 transmits a registration rejection notification to the slave communication device 62 (step S813) , and extinguishes the second LED 32 (step S814). Upon receipt of the registration rejection notification from the master communication device 50 (Yes in step S1210) , the slave communication device 62 extinguishes the first LED 42 (step S1213) . Thus, the registration process is normally terminated without causing any error. Note that the registration process is terminated before completion in either of the following cases: where the slave communication device 61 or 62 does not receive the discovery response in step S1202; where the master communication device 50 does not receive the connection request in step S802; where the slave communication device 61 or 62 does not receive the connection response in step S1204; where the master communication device 50 does not receive the authentication information in step S804 ; where the slave communication device 61 or 62 does not receive the OK response in step S1207; where the slave communication device 61 or 62 does not receive the registration completion notification and the registration rejection notification in steps S1209 and S1210; and where the registration completion button 31 and the registrationrejectionbutton 37 of themastercommunicationdevice 50 are not depressed in step S808 and S809. As described above, in the communication system and the communication device registration method according to the fourth embodiment of the present invention, the registration process cannot be started unless registration start buttons of two communication devices between which a connection is desired to be established are depressed. Accordingly, it is possible to further increase the reliability and safety in establishing a connection. Moreover, the authentication information used for registration is generated on a random basis at the time of a registrationprocess . This allows the authentication information to be changed for each registration process , thereby reducing the possibility that the authentication information is known and misused by the third party. Note that each of the above embodiments has been described with respect to a case where the registration start instruction unit 41 of each of the slave communication devices 21 through 2N and 61 through 6N is an operating button to be operated by the user, and a registration process is started by depressing the operating button. However, the registration start instruction unit 41 may be replaced by a power-on detection unit 48 (see FIG. 17), such that a registration process is automatically started when the power-on detection unit 48 detects that the slave communication device is turned on or a battery is put into the slave communication device. Thus, it is not necessary to provide the registration start button 41 to the slave communication devices 21 through 2N and 61 through 6N, whereby it is possible to reduce the size and cost of the slave communication devices 21 through 2N and 61 through 6N. Further, each of the above embodiments has been described with respect to a casewhere the registration rejection instruction unit 37 is an operating button to be operated by the user. However, the registration rejection instruction unit 37 may be configured so as to measure a predetermined time period to perform time-out control of a process. With this configuration, it is possible to automatically reject a registration process even if LEDs of a pair of communication devices between which a connection is not desired to be established are left on. Furthermore, eachof the above embodimentshas been described with respect to a case where the first and second notification units 42 and 32 are LEDs. However, the first and second notification units 42 and 32 can be any means which is capable of notifying the user that transmission/reception of authentication information is succeeded. For example, the first and second notification units 42 and 32 may be loudspeakers for outputting sound or display screens for displaying characters thereon. Further still, each of the above embodiment has been described with respect to a case where a registration process is started when the slave communication device transmits a discovery request. However, the discovery request may be transmitted from the master communication device. In this case, the slave communication device is required to be configured so as to receive the discovery request from the master communication device a ter the user inputs an instruction to the registration start instruction unit 41 of the slave communication device. An exemplary procedure of the above case is shown in a sequence diagram of FIG. 18. Note that the discovery request and the connection request arenot necessarilytransmittedfromthe same communication device. For example, the discovery request may be transmitted from the master communication device, and the connection request may be transmitted from the slave communication device. Note that a communication device registration method of the present invention may be realized by predetermined program data stored in a storage medium (e.g., a ROM, a RAM, a hard disk, or the like) which allows a CPU to implement a process procedure as described above. The program data may be loaded onto a memory via a storage medium, such as a CD-ROM, a flexible disc, or the like, or may be directly implemented from the storage medium. INDUSTRIAL APPLICABILITY The present invention provides a communication system and a communication registration method which are advantageous, for example, in a case of registering a communication device to another communication device operable to manage communication over the entire system, and the communication system and the communication registration method are suitable, for example, for use where it is desirable for the user to confirm two communication devices by which a registration process is performed.

Claims

1. A communication system in which a master communication device operable to entirely manage the communication system is connected to at least one slave communication device, the at least one slave communication device including: a first registration start instruction unit operable to provide an instruction to start a registration process with the master communication device; a transmission unit operable to transmit predetermined authentication information to the master communication device based on the instruction provided by the first registration start instruction unit; a reception unit operable to receive a reception result of the authentication information from the master communication device; a first notification unit operable to provide a user with the reception result; and a control unit operable to perform the registration process based on a notification from the first notification unit, and the master communication device including: a reception unit operable to receive the authentication information from the at least one slave communication device; a second notification unit operable to provide the user with the reception result of the authentication information; a transmission unit operable to transmit a reception success response to aslave communicationdevicehavingtransmitted first received authentication information; a registration completion instruction unit operable to provide an instruction to register a desired slave communication device to which the reception success response has been transmitted; and a control unit operable to perform the registration process based on the instruction provided by the registration completion instruction unit .

2. The communication system according to claim 1 , wherein the first registration start instruction unit is an operating button which is depressed by the user to provide an instruction to start the registration process.

3. The communication system according to claim 1, wherein the first registration start instruction unit provides an instruction to start the registration process when the at least one slave communication device is turned on.

4. The communication system according to claim 1 , wherein theregistrationcompletioninstructionunit is anoperatingbutton whichis depressedbytheuserto provide an instruction to implement the registration process.

5. The communication system according to claim 1 , wherein the master communication device further includes a registration rejection instruction unit operable to provide an instruction to reject the registrationprocess so as not to register an undesired slave communication device to which the reception success response has been transmitted, and wherein the control unit rejects the registration process based on the instruction provided by the registration rejection instruction unit.

6. The communication system according to claim 5 , wherein the registration rejection instruction unit is an operating button which is depressed by the user to provide an instruction to reject the registration process.

7. The communication system according to claim 5, wherein the registration rejection instruction unit provides an instruction to reject the registration process if the registration completioninstructionunit does not provideanyinstructionbefore a lapse of a predetermined time period since the reception result is provided by the second noti ication unit .

8. The communication system according to claim 1, wherein the first and second notification units are LEDs which are lit up to provide the reception^' result to the user.

9. The communication system according to claim 1, wherein the master communication device further includes a second registration start instruction unit operable to provide an instruction to start a registration process with the at least one slave communication device, and wherein thereceptionunit of themastercommunication device is able to receive the authentication information from the at least one slave communication device after the instruction is provided by the second registration start instruction unit.

10. The communication system according to claim 1, wherein the at least one slave communication device further includes an authentication information generation unit operable to generate the authentication information on a random basis , and wherein the transmission unit of the at least one slave communication device transmits the authentication information generated by the authentication information generation unit to the master communication device.

11. The communication system according to claim 9, wherein the at least one slave communication device further includes an authentication information generation unit operable to generate the authentication information on a random basis , and wherein the transmission unit of the at least one slave communication device transmits the authentication information generated by the authentication information generation unit to the master communication device.

12. The communication system according to claim 9 , wherein the second registration start instruction unit is an operating button which is depressed by the user to provide an instruction to start the registration process.

13. The communication system according to claim 11 , wherein the second registration start instruction unit is an operating button which is depressed by the user to provide an instruction to start the registration process.

14. A master communication device operable to entirely mange asystemconnected to at least one slave communication device, the master communication device comprising: a reception unit operable to receive predetermined authentication information from the at least one slave communication device; a notification unit operable to provide a user with a reception result of the authentication information; a transmission unit operable to transmit a reception success response to a slave communication device having transmitted first received authentication information; a registration completion instruction unit operable to provide an instruction to implement a registration process so as to register a desired slave communication device to which the reception success response has been transmitted, based on the reception result provided by the notification unit and a notification of success or failure provided by the slave communication device to which the reception success response has been transmitted; and a control unit operable to perform the registration process based on the instruction provided by the registration completion instruction unit.

15. The master communication device according to claim 14 , wherein the registration completion instruction unit is an operating button which is depressed by the user to provide an instruction to implement the registration process .

16. The master communication device according to claim 14, further comprising a registration rejection instruction unit operable to provide an instruction to reject the registration process so as not to register an undesired slave communication device to which the reception success response has been transmitted, wherein the control unit rejects the registration process based on the instruction provided by the registration rejection instruction unit.

17. The master communication device according to claim 16 , whereintheregistrationrejection instructionunit is anoperating button which is depressed^' by the user to provide an instruction to reject the registration process.

18. The master communication device according to claim 16 , wherein the registration rejection instruction unit provides an instruction to reject the registration process if the registration completion instructionunit does not provide anyinstructionbefore a lapse of a predetermined time period since the reception result is provided by the notification unit .

19. A slave communication device connected to a master communication device operable to entirely manage a system, the slave communication device comprising: a registration start instruction unit operable to provide an instruction to start a registration process with the master communication device; a transmission unit operable to transmit predetermined authentication information to the master communication device based on the instruction provided by the registration start instruction unit; a reception unit operable to receive a reception result of the authentication information from the master communication device; a notification unit operable to provide a user with the reception result; and a control unit operable to perform the registration process based on a notification from the notification unit .

20. A registration method implemented for registering a slave communication device to a communication system in which a master communication device operable to entirely manage the communication system is connected to at least one slave communication device, the method comprising the steps of: providing an instruction to start a registration process with the master communication device; transmittingpredeterminedauthentication information from the slave communication device to the master communication device based on the instruction to start the registration process; causing the slave communication device to receive the reception result of the authentication information from the master communication device; providing, from the slave communication device, a user with the reception result; causing the slave communication device to perform the registration process based on the reception result; causing the master communication device to receive the authentication information from the slave communication device; providing, from the master communication device, the user with the reception result of the authentication information; causing the master communication device to transmit a reception success response to the slave communication device if the authentication information fromthe slave communication device reaches the master communication device first, and to transmit a reception failure response to the slave communication device if the authentication information from the slave communication device reaches the master communication device later than authentication information from another slave communication device; providing, from the master communication device, an instruction to complete the registration process so as to register a desired slave communication device to which the reception success response has been transmitted; and causing the master communication device to perform the registration process based on the instruction to complete the registration process.

21. A computer-readable program code causing a computer to implement a method for registering a slave communication device to a communication system in which a master communication device operable to entirely manage the communication system is connected to at least one slave communication device, the method comprising the steps of: providing an instruction to start a registration process with the master communication device; transmittingpredeterminedauthenticationinformationfrom the slave communication device to the master communication device based on the instruction to start the registration process; causingthe slave communicationdevice toreceiveareception result of the authentication information from the master communication device; providing, from the slave communication device, a user with the reception result; causing the slave communication device to perform the registration process based on the reception result; causing the master communication device to receive the authentication information from the slave communication device; providing, from the master communication device, the user with the reception result of the authentication information; causing the master communication device to transmit a reception success response to the slave communication device if the authentication information fromthe slave communicationdevice reaches the master communication device first, and to transmit a reception failure response to the slave communication device if the authentication information from the slave communication device reaches the master communication device later than authentication information from another slave communication device; providing, from the master communication device, an instruction to complete the registration process so as to register a desired slave communication device towhich the reception success response has been transmitted; and causing the master communication device to perform the registration process based on based on the instruction to complete the registration process .