Abstract:
[PROBLEM] Person authentication and authentication device of the present invention aims at providing a user with services of easy, inexpensive, highly secure, and reliable person authentication.  
     [MEANS TO SOLVE THE PROBLEMS] Authentication method adopted by the present invention comprises: a step that forwards to a communication device of a user a registration identifier that identifies the user and/or the communication device by including the identifier in an address of registration screen peculiar to the user and/or the communication device; and a step that, when the address is accessed, and a first password is entered and replied to the registration screen, authenticates the user based on the registration identifier and the first password; and a step that sends a login screen display to the user when the authentication step is successful, which the step is comprised of a step where the login screen display comprises a field for entering a second password, and a login identifier to identify the user and/or the communication device; and a step that authenticates the user based on the login identifier contained in the login screen display replied by the user, and the second password.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Technical Field of the Invention  
         [0002]     The present invention generally relates to the transmission of digital information and more particularly to the arrangement and/or handling of digital information for confidential or secured communication including the mechanism for verifying the identity or qualification of a system user. The present invention is well suited to an authentication method or device when a user (client) of such a small potable terminal as a cellular phone, a car phone, PHS (Personal Handy-phone System), PDA (Personal Digital Assistant), etc. uses a network like Internet to access a server which stores desired information.  
         [0003]     2. Prior Art  
         [0004]     Owing to IT technology innovation, the global world based on Internet has been evolved, and its convenience has been spotlighted by the public attention. The information society where information digitalization and Internet are combined has come to greatly impact human activities ranging from company activities down to private life. Users can simultaneously access various servers connected to Internet to obtain versatile data and services. And recently, it is not only desktop personal computers (PCs), but also small portable terminals such as cellular phones, PDA. etc. that can have an access to Internet.  
         [0005]     As a result of Internet linking individuals and companies, it becomes increasingly necessary to safely distribute information (e.g., commercial information or musical information provided only with specific members, or customer information which companies don&#39;t want to be leaked to any irrelevant third party) or electronic commercial transactions (e.g., online shopping which requires transmission of credit card information). The site that wants to limit users who have access to information typically employs a system that registers users online or outline and then admits access to information only by those registered users.  
         [0006]     For safe communication, cryptograph is employed. Cryptograph consists of a secrets keeping mechanism and authentication. A secrets keeping mechanism consists of encryption that encodes plaintext into cipher text, and decryption that decodes encrypted cipher text into plaintext, and it is an algorithm (a cipher system) and a key that dictate encryption and decryption. Typically, a small information device cannot encrypt/decrypt electronic mail, but WWW (hereinafter, simply called “web”) has a secret communication environment that can perform encryption/decryption. Authentication can be roughly classified as person identification, message authentication, and digital signature depending on subject to be identified. Person identification is also called party authentication or user authentication, and thus, it is a technique to be used for a multi-user computer system or for a network system to verify that the party you are communicating with is real, where the simplest way is to use a password. Typically, person identification is done by using a combination of a user ID (or a user name) that a user presets and stores into (a storage for an access authority list in) a server in advance, and a password, in which case a user is required to enter his or her user ID and password when logging in a computer system or a network. When the user enters both data, it is authenticated by cross-checking the two to make sure whether it is the same as the one registered in (the storage for the access authority list in) the server, and only at the time of being authenticated, use of the system is allowed within the limits of the registration made in the access authority list. Here, the user ID is a user identification name in the system, and the password is a character string consisting of numbers and alphabetical letters that the user has arbitrarily chosen.  
         [0000]     Problems to be Solved by the Invention  
         [0007]     However, since a user using a small portable terminal usually makes a key entry with one finger, the conventional authentication method that requires many key entry operations for a user ID and a password, Internet URL, etc. becomes a burden to the user in terms of entering and managing them. On the other hand, there is a need to maintain security to be able to attain an authentication method that uses a user ID and a password for realization of secure communication. Also, unlike a PC, cipher codes available on a small portable terminal are limited in many cases. For example, a cellular phone cannot use a cipher for electronic mail enabled communication, but can use a cipher for WWW (hereinafter, simply called ‘web’) enabled communication. Sending to a small portable terminal a URL for e-mail login containing a user identification part can provide facilities for a user, but when electronic mail cannot be enciphered, there will arise a danger that the URL for the user may be furtively looked at.  
         [0008]     On the contrary, in addition to, or in place of, a user ID and a password, biometrix (bio-authentication) that uses bodily features (such physical features as a finger print, a palm pattern, a vocal pattern, a retinal pattern, etc., handwriting, and key-entry habits) is proposed as a new candidate. Use of biometrix increases security, but a purchase of a device dedicated for reading bodily information (a finger print reader, for example) will become a burden to a user. In addition, it is only such bio-information as is supported by an authentication device that can be used.  
         [0009]     Thus, a generalized object of the present invention is to propose a novel and useful authentication method and device that will help solve the conventional problems.  
         [0010]     More specifically, an exemplified object of the present invention is to propose an authentication method and device that can authenticate a user easily, comparatively cheaply, and safely.  
         [0011]     Further, another exemplified object of the present invention is to offer an authentication method and device that can help lighten a user&#39;s burden by alleviating key entry operations of a user who uses a small portable terminal.  
       BRIEF SUMMARY OF THE INVENTION  
       [0012]     In order to achieve the above objects, an authentication method as one aspect of the present invention comprises the steps of: sending an address of a registration screen to a communication device of a user, the address including a registration identifier for identifying the user and/or the communication device; authenticating the user based on the registration identifier and a first password that is entered in the registration screen and returned when the address is accessed; sending a login screen to the user when the authenticating step succeeds, the login screen including a field into which a second password is entered, and a login identifier for identifying the user and/or the communication device; and authenticating the user based on the login identifier included in the login screen, and the second password that are returned by the user. According to the authentication method, which follows the steps using the registration screen and the first password, the user may circumvent the load of keying the identifier in the login screen and handling the identifier, and thus the user using a small portable terminal particularly benefits from the authentication method. Moreover, the authentication method may ensure the same level of security as the authenticating method using the identifier and the (second) password. Even if he address of the registration screen were sent without using encryption, and resultantly leaked, the first password would secure legitimateness of the user.  
         [0013]     The registration identifier and the login identifier preferably differ from each other. The login identifier that could not be presumed from the registration identifier would prevent the address of the registration screen from providing a clue to an unauthorized login. The first and second passwords may either be the same or different. The same passwords could reduce the load of the user in handling the password.  
         [0014]     The identifier in the login screen may be a device identifier that the communication device automatically sends for particularly identifying the communication device. Some of cellular phones, etc. send a notification of the device identifier (specific identifier for each cellular phone) to the server as part of communication services irrespective of the user&#39;s operations. The device identifier is assigned individually even among the same models, and thus identifies both the model and the user who uses the model. Therefore, utilizing this identifier would allow the user to omit setting the identifier of the communication device independently from the login screen.  
         [0015]     The above step of sending the login screen to the user enables the user to save contents of the login screen in the communication device. This is made possible when the communication device is capable of saving the login screen. Alternatively, the above step of sending the login screen to the user may enable the user to save an address of the login screen in the login screen, where the address of the login screen includes the identifier. In this instance, the communication device, for example, may bookmark a URL of the login screen including the identifier.  
         [0016]     The authenticating step using the registration identifier and the first password may disable the registration screen to be accessed when the authenticating step succeeds. This would prevent someone who might attempt to cast a furtive glance at the address of the registration screen from succeeding in registration on the premise that the authorized user has completed the registration, thereby enhancing the security. On the other hand, even if the one who has cast a furtive glance had completed the registration, the authorized user would become aware of abnormal conditions from inaccessibility to the registration screen, and could take prompt measures such as retrying the registration.  
         [0017]     The first password that has been entered in the registration screen and returned may be accepted only when the password is returned within a predetermined time. This would allow the user authentication using the first password to be implemented when the password is entered in the registration screen and returned within a predetermined time. Even if other than the authorized user could acquire the registration screen, time period would expire while seeking the first password, so as to enhance the security.  
         [0018]     An authentication device as another aspect of the present invention comprises: a storage part that stores user information, a registration identifier, a registration password verification information, login identifier, login password verification information while correlating them with one another; a first control part that sends an address of a registration screen to a communication device of a user, the address including a registration identifier for identifying the user and/or the communication device; a second control part that provides the communication device with the registration screen including a field into which a registration password is entered, and the registration identifier in response to a request for the registration screen from the communication device, and that authenticates the user with reference to the storage part when the user enters the login password in the registration screen and returns the same; and a third control part that provides the communication device with the login screen including a field into which a login password is entered, and the login identifier when the authentication succeeds, and that authenticates the user with reference to the storage part when the user enters the login password in the login screen and returns the same. This authentication device controls the registration through the second control part, and the login through the third control part. The first, second, and third control parts may be the same component, or any two of the control parts may be the same. Since the login screen provided after the registration control includes the login identifier, the user may circumvent the load of keying the same in the login screen and handling the identifier, and thus the user using a small portable terminal particularly benefits from the authentication device. Even if the registration screen were sent or received without using encryption, the registration password would secure that the other party is an authorized user. The registration password and the login password may be either the same or different. Nonetheless, the registration identifier and the login identifier preferably differ from each other. The login identifier that could not be presumed from the registration identifier would prevent the address of the registration screen from providing a clue to an unauthorized login.  
         [0019]     Other objects and further features of the present invention will become readily apparent from the following description of the embodiments with reference to accompanying drawings. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0020]      FIG. 1  is a system organization chart of the authentication system of the present invention.  
         [0021]      FIG. 2  is a rough schematic of a registration screen to be used for the authenticator in the authentication system shown in  FIG. 1 .  
         [0022]      FIG. 3  is a schematic of a login screen that the authenticator uses in the authentication system shown in  FIG. 1 .  
         [0023]      FIG. 4  is a flowchart to explain the steps in the authentication system shown in  FIG. 1 .  
         [0024]      FIG. 5  is a variation example of the flowchart shown in  FIG. 4 . 
     
    
     DESCRIPTION OF CODES  
       [0000]    
       
         
           
               1  Authentication System  
               10 A User (and/or his or her cellular phone)  
               10 B Illegitimate user (and/or his or her cellular phone)  
               20  Information provider  
               30  Internet  
               100  Authenticator  
               110  Control  
               120  Communication port  
               130  Random number generator  
               140  Encryptor/decryptor  
               150  Memory  
               200  Storage  
               210  User management table  
               220  Registration screen saving table  
               230  Login screen management table  
           
         
       
     
       DETAILED DESCRIPTION OF THE INVENTION  
       [0000]     Preferred Embodiments of the Invention  
         [0040]     Below, authentication system  1  of the present invention will be explained by referring to attached figures.  FIG. 1  is a conceptual organization chart of authentication system  1  of the present invention. As shown in  FIG. 1 , authentication system  1  comprises a plurality of users (clients)  10  connected to Internet  30  (here, reference number  10  is to represent  10 A,  10 B, etc.), information provider  20 , and authenticator  100 .  
         [0041]     User  10  can be an individual or a company, and its installation place can be domestic or abroad, but typically, it refers to a platform operated by an individual or enterprise user or software stored on that platform, or it even refers to a user himself in this embodiment of the invention. As a machine that sends and receives, processes and stores information, the platform widely comprises not only a PC but also a digital TV, PDA, a car phone, a cellular phone, PHS, WAP (Wireless Application), a game machine, etc. However, user  10  in this embodiment of the present invention uses a cellular phone comprising a screen scribbling function and software stored in it. The screen scribbling function is a function that serves to capture and save an image, and is widely used in such cellular phones as the i-mode cellular phone manufactured by DoCoMo Co.  
         [0042]     User  10  stores a browser needed for communication with information provider  20  and authenticator  100  via Internet  30 . The browser enables user  10  to use e-mail. Thus, client  10  can communicate with information provider  2 Q and authenticator  100  via wireless communication or can communicate with them over Internet. Such a browser as this can desirably bookmark the URL for information provider  20  and authenticator  100 .  
         [0043]     Information provider  20  stores information and/or services that user  10  desires. In order to admit information access only to a specific user for commercial reasons and/or from information security, information provider  20  generally needs user authentication when a user logs in. For example, the case is where a member alone is allowed to have access to specific information such as a stock forecast, a meeting, a horse-race forecast, etc., or where only an operator is allowed to access confidential information about his company. Information provider  20  can be organized with the function of authenticator  100  included in it, as discussed later, as a one piece or can be connected to it without using Internet  30 . Information provider  20  generally comprises the hardware component of authenticator  100 , and so, a detailed description of it will be omitted here.  
         [0044]     Internet  30  is a typical example of a network, but the present invention does not prohibit itself from being applied for LAN (Local Area Network), MAN (Metropolitan Area Network), WAN (Wide Area Network), commercial exclusive lines (such as America Online), and other online networks.  
         [0045]     Authenticator  100  comprises CPU  110 , communication port  120 , random number generator  130 , memory  140 , encryptor/decryptor  150 , and storage (data storage)  200 . In addition, authenticator  100  can also function as a mail server and a news server. CPU  110  comprises a wide selection of processing units such as MPU or whatever, thus controlling each part of authenticator  100 . Authenticator  100  can comprise dedicated processing units which are controlled by CPU  110  and process various types of databases on data storage  200 . Also, authenticator  100  comprises an input means not included in the illustration (such as a keyboard, a mouse or other pointing devices), a display, etc. Via an input means, the operator of authenticator  100  can enter various kinds of data into storage  200 , and set up necessary software in memory  150  and storage  200 .  
         [0046]     It necessary, authenticator  100  can be connected to other computers through LAN and other network, and CPU  110  can communicate with such computers. In connection with the present invention, CPU  110  can build various types of databases (user managed table  210 , registration screen management table  220  and login screen management table  230 ) stored in storage  200 , and authenticate user  10  by use of a relevant database.  
         [0047]     Communication port  120  includes USB port, IEEE 1394 port, etc., which can be connected, via a modem and a terminal adapter (TA), to various dedicated lines that, in turn, are connected to a public telephone line network and ISDN connectable to Internet (if necessary, through ISP—Internet Service Provider). Further, when authenticator  100  is linked to LAN, communication port  120  also can include a hub and a router.  
         [0048]     Random number generator  130  comprises a program language having a function that generates random numbers. According to the present invention, ID is not determined by user  10 , but CPU  110  allocates a random ID to user  10  based on a random number generated by random number generator  130 .  
         [0049]     When storing into storage  200  a password set up by user  10 , and sending and receiving data over a network, encryptor/decryptor  140  converts (encrypt) data so that a third party may not understand it, and converts (decrypts) the encrypted password of user  10 , extracted from storage  200 , to be decipherable when authenticator  100  authenticates user  10 . It is a procedure (an algorithm), and a key which is a parameter consisting of alphanumericals and symbols randomly lined up (a character string) that dictate encryption and decryption. The procedure is a fixed part of hardware and software, and the key is a convertible character string. The mechanism for a procedure (an encryption system) differs between an encryption key and a decryption key even in the secret key encryption where a sender and a receiver share the same key in confidence, and the encryption key can be made open, and the decryption key can be an open key encryption that is kept secret on the side of a receiver. Further, any encryption techniques known in the industry can be applied to the present invention, and so, detailed description of encryption will be omitted here.  
         [0050]     Memory  150  contains RAM and ROM, thereby saving temporarily data read out from, and written to, storage  200 . Memory  150  stores various kinds of software, firmware, and other software necessary for the operation of CPU  110 .  
         [0051]     Mailer  160  is software for sending e-mail to, and receiving e-mail from, user  10 , and comprises a storage part, not illustrated in the figure, for a receiving tray to store mail received from user  10  and others, a sending tray to store mail bound for user  10  and others, an already sent tray to store mail already sent to others, an already deleted tray to store mail deleted from arbitrary trays, and a drafting tray to store mail on a drafting stage. In this embodiment of the present invention, the mail server for authenticator  100  is provided separately from the authentication device, but as stated above, authenticator  100  can act as a mail server. Mailer  160  sends to user  10  a message like a stereotyped phrase (e.g., “Thank you for accessing our URL. Please access the registration screen below (or the activation screen) within 3 hours.”), a registration screen URL peculiar to user terminal  10  (i.e., a URL including a registration identifier explained later) and other information. Here, the reason for writing ‘a registration screen peculiar to a user terminal’ is because since depending on its type, a cellular phone has a different format for a site from where information can be received, it is necessary to use one that fits to the user&#39;s cellular phone type as explained later. However, the present invention does not essentially require that authenticator  100  comprise mailer  160 .  
         [0052]     Although storage  200  comprises databases for user management table  210 , registration screen management  220  and login screen management table  230 , it is not limited to this.  
         [0053]     User management table  210  contains, by way of illustration, user  10 &#39;s name, address, sex, age, birthday, telephone number, e-mail address, machine type of the cellular phone used, authentication information for one or more passwords (it can be the password itself, but it should include all information necessary to authenticate them), type of a process corresponding to type of a cellular phone, bank account number, credit card number, key for encryption, and other ID information. Here, ‘type of a process corresponding to type of a cellular phone’ is not necessarily needed all the time, but when the format of the Web screen displayable depending on the type of a cellular phone changes or its preservation function changes (e.g., the content of a certain Web screen cannot be preserved, but its bookmark can be preserved), a process that fits for a pertinent cellular phone is performed (e.g., the Web screen is changed so that it fits for the cellular phone, and then, necessary ID is inserted in its URL). Registration of user  10  is performed offline in advance by authenticator  100  and its administrator using a relevant cellular phone, mail or fax, etc., and then later, upon online connection request from user  10 , authenticator  100  will re-register user  10 . Online registration operation is done by user  10  who completes and sends a specific form provided by CPU  110 . By using his or her own terminal, user  10  can confirm his or her ID information at any time, and can change it if necessary.  
         [0054]     By referencing user management table  210 , CPU  110  authenticates user  10  when user  10  wants to access authenticator  100 . In addition, when user  10  updates or deletes registered information, further additional authentication can be performed. Authenticator  100  can, if necessary, be provided with a voice authenticator that authenticates user  10  by his voiceprint, in which case the ID information should contain the voiceprint of user  10 .  
         [0055]     Registration screen management table  220  houses registration screen  221  which is a registration screen peculiar to a user and/or a communication device that the user uses (i.e., a cellular phone in this embodiment). As explained later, registration screen  221  is provided by CPU  110 , via e-mail, to the e-mail address of the cellular phone of user  10  registered in advance. It is preferable that such provision of registration screen  221  be limited in terms of time. By so doing, even if non-legitimate users (false users) obtain the URL of registration screen  221 , time-out state is brought in, as explained later, while they fumble for the password, thus improving security.  
         [0056]     Registration screen  221  (reference number ‘ 221 ’ represents  221   a ,  221   b , etc.) comprises a number of types and fields as shown in FIGS.  2  ( a ) through ( d ). Here.  FIG. 2  is a rough block chart for registration screen  221  to be presented to user  10  from authenticator  100  via Web enabled communication. In the same chart,  FIG. 2  ( a ) shows the first registration screen  221   a  to be presented to user  10 .  FIG. 2  ( b ) shows registration screen  221   c  that is given when valid user  10  enters or replies an invalid registration password in registration screen  221   a .  FIG. 2  ( c ) shows registration screen  221   d  that is given when valid user  10  enters or replies a registration password in registration screen  221   a  after the password has expired.  FIG. 2  ( d ) shows registration screen  221   d  that is given when a person who does not use the same type of machine as the user and/or communication device registered on user management table  210  enters or replies the registration password in registration screen  221   a.    
         [0057]     First in reference to  FIG. 2  ( a ), registration screen  221   a  comprises fields for registration identifier  222 , registration password  223 , send button  224  and effective period  225 . However, registration screen management table  220  houses registration screen  221   a  where registration identifier  222  and effective period  225  are planned to be entered (i.e., before they are entered). Field  222  is an ID that identifies the user and/or the communication device registered in user management table  210 . Registration identifier  222  is imbedded in registration screen  221   a  in a way invisible or hidden from a person who receives registration screen  221   a  or in such a way that it can be confirmed by the person who receives registration screen  221   a . In this embodiment, as stated above, registration identifier  222  uses, on as-is basis, what is sent to user  10  by mailer  160 , but it can use other identifier. Since registration identifier  222  is already imbedded in registration screen  221   a , user  10  is relieved from the burden of entering or managing this. Field  223  is a field for entering the registration password (e.g., of eight digit characters) that the user has previously chosen and registered in user management table  210 . Field  224  is a field to be clicked when the user has entered the registration password, which is then returned to authenticator  100  through Web enabled communication. Field  225  is built in such a way as can be confirmed by user  10  or in a hidden invisible way, i.e., it is a field that indicates an effective period of time (e.g., three hours) between when user  10  receives a message from mailer  160  and when he must complete the registration password. For the starting and ending time for effective period  225 , any arbitrary time can be set.  
         [0058]     In reference to  FIG. 2  ( b ), registration screen  221   b  comprises fields for message  226  and for ‘Return’ button  227 . Message  226  is displayed to indicate that the registration password entered is wrong and that a password retry is prompted. ‘Return’ button  227  is a button that makes it possible for user  10  to retry the password by switching registration screen  221   b  to  221   a.    
         [0059]     In reference to  FIG. 2  ( c ), registration screen  221   c  comprises a field for message  228 . Message  228  informs user  10  that the effective period entered has already expired. In this embodiment, registration screen  221   c  is so organized that it is given in preference to registration screen  221   b  if the effective period is over, regardless of whether registration password  223  entered into registration screen  221   a  is right or wrong.  
         [0060]     In reference to  FIG. 2  ( d ), registration screen  221   d  comprises a field for message  229 . Message  229  informs user  10  that the type of cellular phone used is different from that previously registered in user storage database  210 . Registration screen  221   d  is given when a user&#39;s cellular phone  10  automatically posts the device identifier (i.e., the proper identifier of the cellular phone) to authenticator  100 . Now, to take an example, let&#39;s consider a case where user  10 B gets possession of URL plus registration password for registration screen  221   a  that is sent to user  10 A, thus obtaining registration screen  221   a  and then entering the registration password in response. If the cellular phone of user  10 B is of a type that sends its device identifier to authenticator  100  automatically, control part  110  can verify that the device identifier of user  10 B is different from that of user  10 A based on other authentication information stored in registration identifier  222  and user management table  210 . As a result, subsequent login screen display  231   a  can be prevented from being sent.  
         [0061]     Login screen management table  230  houses login screen display  231  (reference number ‘ 231 ’ is to represent  231   a ,  231   b , etc.) into which a login identifier identifying a user and/or communication device (i.e., a cellular phone in this embodiment) is planned to be imbedded (i.e., before the imbedding takes place) in a way hidden from user  10 . Login screen  231  to be provided to user  10  has an identifier imbedded; therefore, user  10  need not enter this from the cellular phone, thus contributing to the alleviation of key operation. Even if an imprudent person peeks at the login screen display  231  on the cellular pone, he cannot recognize the identifier, thus improving security.  
         [0062]     Login screen display  231  comprises, as shown in FIGS.  3  ( a ) and ( b ), a number of types and fields. Here,  FIG. 3  is a rough block figure of login screen display  221  to be given to user  10  from authenticator  100  via Web enabled communication. In the same figure.  FIG. 3  ( a ) shows login screen display  231   a  that is given when legitimate user  10  enters or replies a correct password to registration screen  221   a  before the effective period expires, and as a result, it is authenticated by control part  110 .  FIG. 3  ( b ) shows login screen display  231   a  that is given when legitimate user  10  enters or replies a wrong login password to registration screen  231   a.    
         [0063]     First in reference to  FIG. 3  ( a ), login screen display  231   a  comprises fields for login identifier  232 , password  233 , and send button  237 . However, login screen display  231   a  in which login identifier  232  is planned to be inputted (i.e., before it is inputted) is stored in login screen display storage table  220 . The content of login screen display  231   a  in which login identifier has been entered is saved in user cellular phone  10 , or part or all of login identifier  232  or URL of login screen display  231   a  containing information related to this is saved (book-marked) by user cellular phone  10 .  
         [0064]     Field  232  indicates an identifier that identifies a user and/or his communication device registered in user management table  210 . A login identifier is imbedded in registration screen  221   a  so as to be confirmed by a user or, more preferably, in a way hidden, invisible from user  10  who receives login screen display  221   a . It is preferable that login identifier  232  differs from registration identifier  222 , because in this embodiment, as stated above, registration identifier  222  uses on as-is basis what is sent to user  10  by mailer  160 , and registration identifier  222  is exposed to a danger of being seen furtively by an imprudent person since it is sent to user  10  in an unencrypted way via e-mail. Since login identifier  223  is already imbedded in login screen  231   a , user  10  is relieved from the burden of entering and administering this login identifier. Field  233  is a field for entering a login password (of eight characters, for example) that user  10  has chosen and registered in user management table  210  in advance. A login password can be the same as a registration password, or it can be a different password. Field  234  is a field that is clicked to reply a registration password to authenticator  100  via Web enabled communication after the user has inputted the registration password.  
         [0065]     In reference to  FIG. 3  ( b ), login screen display  231   b  comprises fields for message  235  and ‘Return’ button  236 . Message  235  indicates to user  10  that login password entered is wrong, and a retry is prompted. ‘Return’ button  236  is a button that makes it possible for user  10  to retry the password by switching login screen display  231   b  to  231   a.    
         [0066]     In reference to  FIG. 4 , a description will be made below of a series of actions taken when user  10  gets authenticated by authenticator  100  by taking advantage of authentication system  1 . Here,  FIG. 4  is a flowchart for explaining a series of actions followed when user  10  gets authenticated by authenticator  100  by using authentication system  1 . Here, cellular phone  10 A, shown in  FIG. 1 , is supposed to indicate the cellular phone of a legitimate user, and cellular phone  10 B, the cellular phone of an illegitimate user.  
         [0067]     At first, user  10 A makes a user registration request to an administrator of authenticator  100  offline using a cellular phone, FAX, or mail (step  1002 ). If user  10  has a desktop PC besides a cellular phone, it is quite easy to make an input using a mouse or a keyboard, thus being able to directly make a user registration to authenticator  100  online. However, in the present case, a cellular phone, rather than a PC, is to be registered.  
         [0068]     Authenticator  100  or its administrator that receives the request, makes an entry of user information requested by user  10  (i.e. user  10 &#39;s name, address, sex, age, birthday, telephone number, e-mail address, type of his cellular phone, authentication information for his password (for registration and login) (which can be the password itself but should include all information needed to authenticate this), types of services selected, necessary charge information (bank account, credit card, etc.), key for encryption, and other ID related information), and registers it in user management table  210  of storage  200  (step  1004 ). At the time of registration, CPU  110  encrypts user information via encryptor/decryptor  140 , or merely stores the information in user management table  210  of storage  200  without encrypting it.  
         [0069]     When authenticator  100  or its administrator completes the registration of the user information, CPU  110  sends URL of registration screen  221  to the e-mail address of cellular phone  10 A via mailer  160  and communication port  120 , as well as writing registration identifier  222  and effective period  225  into corresponding registration screen  221   a  (step  1006 ). Before sending URL of registration screen  221 , CPU  110  refers to user management table  210  of storage  200  in advance, thus acquiring URL of accessible registration screen  221   a  into the type of cellular phone  10 A, and randomly generating a registration identifier, by using random number generator  130 , that identifies the cellular phone  10 A, which is to be included in registration screen  221   a . The timing with which CPU  110  gives e-mail can be at the time when registration of user information into authenticator  100  is completed or at the time user  10  makes a request.  
         [0070]     Upon receipt of an e-mail that includes URL of registration screen  221   a  (step  1008 ), user  10 A calls upon registration screen  221   a  (step  1010 ). At this point of time, as the URL is contained in the e-mail, user  10 A need not use the key pad of his cellular phone to input the URL purposely. Instead, user  10 A can reverse the URL of the e-mail to push ‘Decision’ key, usually equipped, and click/double-click the URL, thereby calling the URL of registration screen  221   a.    
         [0071]     In response to this, CPU  110  displays the corresponding registration screen  221   a  (step  1012 ). CPU  110  determines the type of the cellular phone, calling for the URL, based on the number, contained in the URL, which is peculiar to a machine type. Registration identifier  222 , which is peculiar to cellular phone  10 A, is written in registration screen  221   a  in a modifiable way. CPU  110  prompts user  10  to enter the registration password via registration screen  221   a . Generally speaking, the browser for a PC can use encryption for Web enabled communication and e-mail enabled communication, but in the case of a cellular phone, encryption can be applied for Web enabled communication, while on the other hand it cannot be applied for e-mail enabled communication. Therefore, according to the embodiment of the present invention, when a URL containing a number specific to the machine type of a cellular phone is given via e-mail, since it is exposed to a danger of being furtively listened to, resulting in the URL being leaked, the password should be confirmed, and it should be verified that the request is from legitimate user  10 A.  
         [0072]     Later on, user  10 A puts the registration password from registration screen  221   a  into field  223  to reply to authenticator  100  (step  1011 ). Communication at this time is changed from e-mail enabled communication to Web enabled communication, and the registration password is encrypted for transmission; thus, there is no danger for the password to be stolen and leaked.  
         [0073]     If a wrong registration password is entered, registration screen display  221   b  is sent to user  10 A, who is prompted to retry the registration password. At this time, considering a case where cellular phone  10 A was forgotten somewhere or stolen, and the registration password is used by illegitimate user  10 B, it is possible to make the registration screen  221   a  unusable if illegitimate user  10 B makes as many errors consecutively in retrying the password as the times set up when the registration password was settled, even if the registration screen  221   a  is still within the effective period. If the effective period defined in field  225  has expired, registration screen  221   c  will be sent to user  10 A to indicate this. In this case, user  10  still make an online or offline contact with authenticator  100  or its administrator afresh, requesting that URL of new registration screen  221   a  be sent. When illegal person  10 B takes possession of the URL and registration password, and inputs the registration password to field  223  of registration screen  221   a , and if cellular phone  10 B of the illegal person sends its phone type identifier automatically, registration screen  221   d  will be sent to user  10 B, thereby warning him that a machine type used is wrong.  
         [0074]     If user  10 A encrypts and sends a correct registration password to authenticator  100  within the effective period, CPU  110  will decrypt the received registration password via encryptor/decryptor  140 , and authenticate it by referencing the authentication information of the registration password stored in user management table  210  of storage  200 . If the authentication is successful and CPU  110  authenticates user  10 A, control of the registration by CPU  110  will terminate (step  1016 ).  
         [0075]     Next, when control of the registration ends and legitimate user  10 A is authenticated, CPU  110  will write login identifier  232  into login screen  231   a , and send it to user  10 A (step  1018 ). As stated above, some machine types of cellular phones may send a machine identifier automatically; so, CPU  110  can use it for login identifier  232 . But even if it is not used, no problems will arise, and thus it does not follow that the present invention will be restricted by whether or not the cellular phone itself can issue an identifier. In this embodiment of the present invention, CPU  110  imbeds login identifier into login screen  231   a  in a way hidden from user  10 A, and sends login screen  231   a  to user  10 A after encrypting it at encryptor/decryptor  140 . Since login screen  231   a  is sent in an encrypted state, there is no danger that login identifier  232 , which is imbedded in login screen  231   a  in a hidden state, will be furtively seen and leaked.  
         [0076]     Then, user  10 A will use the screen memo function of cellular phone  10 A to save login screen  231   a  (step  1020 ). Such an action corresponds to the screen saving for a PC. CPU  110 , by the way, takes step  1018 , because referencing user management table  210 , it is aware that user  10 A can perform step  1020 .  
         [0077]     When user  10 A wants to access authenticator  100 , user  10 A will call the login screen saved on the cellular phone (step  1022 ), and enter and send login password  233  to authenticator  100 . Since the identifier for user  10  is imbedded in the login screen in advance, user need not enter identification information afresh on login screen  231   a , thus making the key operation simple. As already stated above, login password  233  can be the same as, or different from, the registration password. Since the sending of the login screen from user  10  to authenticator  100  is done over Web, the content of login screen  231   a  will be encrypted, and so, there is no danger that ID information or login password for user  10  will be stealthily seen and get leaked.  
         [0078]     If a wrong login password  233  is entered, login screen  231   b  will be sent to user  10 A, thus prompting a retry of login password  233  to be made.  
         [0079]     If user  10 A encrypts and sends a correct login password  233  to authenticator  100 , CPU  110  will decrypt received login password  233  via encryptor/decryptor  140 , and verifies it against authentication information of the login password stored in user management table  210  of storage  200 . If the verification is successful, and CPU  110  authenticates user  10 A, control of the login by CPU  110  will end (step  1026 ). After that, CPU  110  will make it possible for user  10 A to access information provider  20 . As a result, user  10 A will access information in information provider  20  by way of simple key operation.  
         [0080]      FIG. 5  is a variation example of  FIG. 4 . In  FIG. 5 , CPU is previously aware from user management table  210  that user  10 A cannot perform step  1020 , but can only bookmark URL of the login screen. Therefore, in place of step  1018 , it will send URL of login screen  231   a  which contains login identifier  232  (step  1028 ). In response to this, user  10 A will bookmark such URL (step  1030 ). When user  10 A wants to make an access, he will call login screen  231   a  whose URL is bookmarked in his cellular phone (step  1032 ), make authenticator  110  display login screen  231   a  (step  1034 ), and then run into step  1024 .  
         [0081]     So far, a description of a preferable embodiment of the present invention has been given, but a variety of variations and changes of the present invention are feasible in the scope of its application.  
         [0000]     Effects of the Invention  
         [0082]     The authentication method and device used for the present invention will assure an easy, inexpensive, highly secure, and sure authentication operation for a user in general, particularly for such a user as uses a communication device whose key operation is complicated.