Abstract:
A storing unit stores a regular telephone number of a user and a provisional telephone number corresponding to the regular telephone number. An acquiring unit acquires a provisional telephone number of a receiver and a regular telephone number of a caller who called at the provisional telephone number of the receiver. A searching unit searches a regular telephone number corresponding to the provisional number of the receiver from the storing unit. A call establishing unit establishes a call between the caller and the receiver corresponding to the regular telephone number searched.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a technology for preventing a leakage of personal information such as a telephone number while establishing a telephone call quickly and efficiently. 
   2. Description of the Related Art 
   Conventionally, when a user uses a telephone terminal such as a cellular telephone to make a call, the user dials a telephone number of a destination. To facilitate the dialing process, the telephone terminal is typically provided with functions such as a phonebook function, an abbreviated dialing function, and an outgoing/incoming call register function. 
   However, if the user looses the telephone terminal, personal information registered in these functions can be leaked and illegally misused by a malicious third party. 
   To solve this problem, Japanese Patent Application Laid Open No. 2002-261935 discloses a technology for generating a provisional telephone number corresponding to a regular telephone number. Thus, if a user notifies another party of the provisional number, the user can receive a call from the other party without notifying the regular number. 
   However, the conventional technology is inefficient because the user needs to notify the other party of the provisional number. 
   Moreover, the provisional number expires after a predetermined time duration to enhance security. Therefore, the user is required to take the trouble of notifying the other party of the provisional number each time he wants to receive a call. 
   Thus, it is imperative to devise a technology for preventing leakage of personal information such as telephone numbers while establishing telephone calls quickly and efficiently. 
   SUMMARY OF THE INVENTION 
   It is an object of the present invention to at least solve the problems in the conventional technology. 
   An apparatus according to one aspect of the present invention, which is for managing information regarding a telephone number of a user, includes a storing unit that stores a regular telephone number of the user and a provisional telephone number corresponding to the regular telephone number; an acquiring unit that acquires a provisional telephone number of a receiver and a regular telephone number of a caller who called at the provisional telephone number of the receiver; a searching unit that searches a regular telephone number corresponding to the provisional number of the receiver from the storing unit; and a call establishing unit that establishes a call between the caller and the receiver corresponding to the regular telephone number searched. 
   A method according to another aspect of the present invention, which is for managing information regarding a telephone number of a user, includes storing a regular telephone number of the user and a provisional telephone number corresponding to the regular telephone number; acquiring a provisional telephone number of a receiver and a regular telephone number of a caller who called at the provisional telephone number of the receiver; searching a regular telephone number corresponding to the provisional number of the receiver from the regular telephone number of the user stored at the storing; and establishing a call between the caller and the receiver corresponding to the regular telephone number searched. 
   A computer-readable recording medium according to still another aspect of the present invention stores a computer program that causes a computer to execute the above method according to the present invention. 
   The above and other objects, features, advantages and technical and industrial significance of this invention will be better understood by reading the following detailed description of presently preferred embodiments of the invention, when considered in connection with the accompanying drawings. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a diagram of a telephone-number management system according to an embodiment of the present invention; 
       FIG. 2  is a functional block diagram of a telephone-number management server according to the present embodiment; 
       FIG. 3  is an example of an ID/password management table; 
       FIG. 4  is an example of a subscriber-number management table; 
       FIG. 5  is an example of a one-time-number management table; 
       FIG. 6  is an example of a history-information management table; 
       FIG. 7  is a flowchart of a processing procedure performed by the telephone-number management server for registering user information; 
       FIG. 8  is an example of screens displayed at a telephone terminal requesting for an access to the telephone-number management server; 
       FIG. 9  is an example of screens displayed at a telephone terminal when “change/delete” is selected in an address-book edit menu; 
       FIG. 10  is a flowchart of a processing procedure performed by the telephone-number management server for generating a provisional number; 
       FIG. 11  is an example of an address-book/history screen; 
       FIG. 12  is an example of a list of registered users; 
       FIG. 13  is an example of a notification screen displayed at a telephone terminal when notifying a receiver&#39;s provisional number; 
       FIG. 14  is a flowchart of a processing procedure performed by the telephone-number management system for establishing a call; and 
       FIG. 15  is an example of an incoming-call register screen. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   Exemplary embodiments of the present invention will be described below with reference to the accompanying drawings. It should be noted that the present invention is not limited to these embodiments. 
   A telephone number management server (hereinafter, “server”) according to the present embodiment stores identification data for identifying a user with the user&#39;s regular telephone number (hereinafter, “regular number”) in a storing unit. When a request is received from a caller to provide a provisional telephone number (hereinafter, “provisional number”) of a receiver, the server generates a provisional number, associates the provisional number with the receiver&#39;s regular number, and notifies the caller of the provisional number. 
   When the receiver&#39;s provisional number and the caller&#39;s regular number are received from the caller, the server searches the receiver&#39;s regular number from the storing unit and notifies a telephone exchange (hereinafter, “exchange”) of the regular number, to establish a call between the caller and the receiver. 
   Thus, by using the server, users can efficiently call each other without knowing the other&#39;s regular number. Moreover, a regular number is prevented from being leaked and illegally misused by a malicious third party. 
     FIG. 1  is a diagram of a telephone-number management system according to an embodiment of the present invention. The telephone-number management system includes a telephone-number management server  100  that is connected to a service control server  60  and a session initiation protocol (SIP) server  70 . The SIP server  70  is connected to a base station  40  though an internet protocol (IP) network. 
   The service control server  60  is connected to an exchange  50 , and the exchange  50  is connected to a base station  30  through an exchange network. A telephone terminal  10  and an IP telephone terminal  20  communicate through the base station  30  and the base station  40 , respectively, by wireless communication. 
   The telephone terminal  10  is, for example, a cellular telephone that is used to make calls through a telephone network. The IP telephone terminal  20  is, for example, an internet telephone that is used to make calls through the Internet. 
   When the base station  30  receives information (including a caller&#39;s regular number, a receiver&#39;s provisional number etc.) from the telephone terminal  10 , the base station  30  transmits the information to the exchange  50  through the exchange network. When the base station  30  receives information (including a receiver&#39;s provisional number etc.) through the exchange network transmitted from the exchange  50  to the telephone terminal  10 , the base station  30  transmits the information to the telephone terminal  10 . 
   When the base station  40  receives information from the IP telephone terminal  20  (including a caller&#39;s regular number, a receiver&#39;s provisional number etc.), the base station  40  transmits the information to the SIP server  70  through the IP network. When the base station  40  receives information (including a receiver&#39;s provisional number etc.) through the IP network transmitted from the SIP server  70  to the IP telephone terminal  20 , the base station  40  transmits the information to the IP telephone terminal  20 . 
   The exchange  50  requests the service control server  60  to provide a receiver&#39;s regular number, and requests an exchange (not shown) on the receiver&#39;s side to call the receiver. Specifically, the exchange  50  transmits an initial DP to the service control server  60  (the initial DP includes a caller&#39;s regular number and a receiver&#39;s provisional number etc.). The exchange  50  then receives the receiver&#39;s regular number and zone area from the service control server  60 , and requests the exchange on the receiver&#39;s side to call the receiver&#39;s telephone terminal based on the information received. 
   When the service control server  60  receives the initial DP from the exchange  50 , the service control server  60  requests the telephone-number management server  100  to convert the receiver&#39;s provisional number included in the initial DP to a corresponding regular number. When the receiver&#39;s regular number is acquired, the service control server  60  transmits the receiver&#39;s regular number and the caller&#39;s regular number to the exchange  50 . 
   When the SIP server  70  receives a caller&#39;s regular number and a receiver&#39;s provisional number from the IP telephone terminal  20  through the base station  40 , the SIP server  70  requests the telephone-number management server  100  to convert the receiver&#39;s provisional number to a corresponding regular number. When the receiver&#39;s regular number is acquired, the SIP server  70  makes a request to call the receiver&#39;s IP telephone terminal. 
   The telephone-number management server  100  manages regular numbers of users. When the telephone-number management server  100  receives a request to convert a receiver&#39;s provisional number to a regular number from the service control server  60  or the SIP server  70 , the telephone-number management server  100  converts the receiver&#39;s provisional number to the regular number, and notifies the service control server  60  or the SIP server  70  of the regular number. In this example, only a single telephone number management server is shown for the matter of convenience. However, a plurality of telephone number management servers can be employed to disperse the load. 
     FIG. 2  is a functional block diagram of the telephone-number management server  100 . The telephone-number management server  100  includes a communication unit  110 , an authentication processing unit  120 , a storing unit  130 , an edit processing unit  140 , a user-group management unit  150 , a one-time-number management unit  160 , and a history-information management unit  170 . 
   The communication unit  110  uses a predetermined communication protocol to communicate with the service control server  60  and the SIP server  70 . When the authentication processing unit  120  receives a request to access the telephone-number management server  100  from the telephone terminal  10  or the IP telephone terminal  20 , the authentication processing unit  120  authenticates the user of the terminal from which the request is made (hereinafter, requesting terminal) based on an ID/password-management table  130   a  stored in the storing unit  130 . 
     FIG. 3  is an example of the ID/password management table  130   a . The ID/password management table  130   a  includes items of “group identification (ID)” and “password”. The group ID is used to identify a group to which a user belongs, and the password is used to authenticate a user belonging to the corresponding group. Specifically, a password “xxxx” corresponds to a group ID “AAA”, a password “yyyy” corresponds to a group ID “BBB”, and a password “zzzz” corresponds to a group ID “CCC”. 
   When the edit processing unit  140  receives, from the telephone terminal  10  or the IP telephone terminal  20  through the authentication processing unit  120 , a request to make a new registration or a revision in user information, the edit processing unit  140  registers new or revised information received from the requesting terminal in a subscriber-number management table  130   b  stored in the storing unit  130 . 
     FIG. 4  is an example of the subscriber-number management table  130   b . The subscriber-number management table  130   b  includes items of “user name” used for identifying a user, “regular number” of the user, “e-mail address” of the user, “group ID” of the user, and “provisional number” of the user. Moreover, the subscriber-number management table  130   b  includes an item of “redial” for indicating whether the user approves that the provisional number can be redialed. 
   For example, information corresponding to a user with a user name “A” includes a regular number “090-aaaa-xxxx”, an e-mail address “oooo”, and a group ID “AAA”. Moreover, redialing is “disapproved”, and the provisional number is “none (not determined)”. Descriptions for user names “B” to “E” are omitted. Users with user names “A, B, and C” belong to a group specified by the group ID “AAA”, and users with user names “D and E” belong to a group specified by a group ID “BBB”. 
   When the user-group management unit  150  receives a request to provide a receiver&#39;s provisional number from the telephone terminal  10  or the IP telephone terminal  20  through the authentication processing unit  120 , the user-group management unit  150  notifies the requesting terminal of the receiver&#39;s provisional number. 
   Specifically, when such a request is received, the user-group management unit  150  displays at the requesting terminal, a list of user names included in the subscriber-number management table  130   b . When a user name is selected at the requesting terminal, the user-group management unit  150  passes the selected user name to the one-time-number management unit  160 . 
   The user-group management unit  150  then acquires a provisional number corresponding to the receiver&#39;s user name from the one-time-number management unit  160 , notifies the requesting terminal of the provisional number, and registers the provisional number in the subscriber-number management table  130   b.    
   Instead of displaying all of the user names registered in the subscriber-number management table  130   b  at the requesting terminal, the user-group management unit  150  can display only user names belonging to the same group. For example, if the caller&#39;s user name is “A”, only the user names “B and C” belonging to the same group as “A” are displayed. 
   The one-time-number management unit  160  generates a provisional number. Moreover, when a receiver&#39;s provisional number is received from the telephone terminal  10  or the IP telephone terminal  20 , the one-time-number management unit  160  converts the provisional number to a regular number. Specifically, when the one-time-number management unit  160  acquires a user name from the user-group management unit  150 , the one-time-number management unit  160  generates a provisional number corresponding to the user name, and passes the generated provisional number to the user-group management unit  150 . The one-time-number management unit  160  also generates a provisional number corresponding to a caller&#39;s regular number. A provisional number is determined based on “a number recognized by a server + a random value”. 
   When the one-time-number management unit  160  generates a provisional number, the one-time-number management unit  160  determines whether the same number is already registered in the subscriber-number management table  130   b . When the same number is already registered, the one-time-number management unit  160  changes the generated provisional number to a different number. 
   The one-time-number management unit  160  records a usage status of a provisional number in a one-time-number management table  130   c  stored in the storing unit  130 .  FIG. 5  is an example of the one-time-number management table  130   c . The one-time-number management table  130   c  includes items of “serial number”, “regular number”, and “usage status”. The “usage status” indicates whether a provisional number corresponding to the “regular number” is being used. 
   For example, a provisional number corresponding to a regular number “090-xxyy-zzzz” of serial number “2” is “in use”. A provisional number corresponding to a regular number “090-xxxx-yyyy” of serial number “3” is “in use” and has a duration of three days. The one-time-number management unit  160  sets a duration by referring to the item of “redial” in the subscriber-number management table  130   b . For example, if a user approves that the provisional number can be redialed within a duration of three days, the duration of the provisional number becomes three days. 
   When the one-time-number management unit  160  generates a provisional number, the one-time-number management unit  160  sets the usage status as “in use”. After the duration elapses, the one-time-number management unit  160  sets the usage status as “not in use” and erases the provisional number from the subscriber-number management table  130   b . When a specific time-duration (e.g. three days) is registered as the usage status, the one-time-number management unit  160  sets the usage status to “not in use” and erases the provisional number from the subscriber-number management table  130   b  when three days elapses after the registration. 
   Moreover, when the one-time-number management unit  160  receives a receiver&#39;s provisional number and a caller&#39;s regular number from the telephone terminal  10  or the IP telephone terminal  20  through the authentication processing unit  120 , the one-time-number management unit  160  searches a regular number corresponding to the provisional number from the subscriber-number management table  130   b , and notifies the service control server  60  or the SIP server  70  of the searched regular number. For example, referring to  FIG. 4 , when the provisional number received is “0120-xxxx-yyyy”, the regular number is “090-bbbb-yyyy”. 
   When the one-time-number management unit  160  notifies the service control server  60  or the SIP server  70  of the receiver&#39;s regular number, the one-time-number management unit  160  determines whether to notify the caller&#39;s provisional number by referring to the item of “redial” in the subscriber-number management table  130   b.    
   Specifically, when redialing is “disapproved”, the one-time-number management unit  160  notifies the service control server  60  or the SIP server  70  of the caller&#39;s identification data stored in the telephone-number management server  100  and the receiver&#39;s regular number. When “reserve” is indicated at the item of “redial”, the one-time-number management unit  160  notifies the service control server  60  or the SIP server  70  of the caller&#39;s provisional number (in this case, the telephone-number management server  100  searches the caller&#39;s provisional number from the subscriber-number management table  130   b  by the caller&#39;s regular number), in addition to the receiver&#39;s regular number. 
   The history-information management unit  170  registers, as history information, past calls of a caller and a receiver in a history-information management table  130   d  stored in the storing unit  130 . Moreover, when the history-information management unit  170  receives a request to notify history information from the telephone terminal  10  or the IP telephone terminal  20 , the history-information management unit  170  notifies the requesting terminal of the information registered in the history-information management table  130   d.    
     FIG. 6  is an example of the history-information management table  130   d . The history-information management table  130   d  includes items of “group ID”, “user name”, “serial number”, “receiver”, “time of outgoing call”, “caller”, and “time of incoming call”. 
   For example, history information of a user with a user name “A” belonging to group ID “AAA” at serial number “1” is described as follows. The user “A” made call to a receiver “B” on “2004 Dec. 20” at “11:05”, and received a call from a caller “C” on “2004 Dec. 20” at “13:40”. 
     FIG. 7  is a flowchart of a processing procedure performed by the telephone-number management server  100  for registering user information. When the authentication processing unit  120  receives a request to access the telephone-number management server  100  from the telephone terminal  10  or the IP telephone terminal  20 , the authentication processing unit  120  displays, at the requesting terminal, an authentication screen  100   a  shown in  FIG. 8  (step S 101 ). 
   When a user of the requesting terminal inputs a group ID and a password in the authentication screen  100   a , the authentication processing unit  120  acquires the group ID and the password (step S 102 ), and determines whether the group ID and the password are correct by referring to the ID/password management table  130   a  (step S 103 ). When the group ID and the password are incorrect (No at step S 103 ), the system control returns to step S 101 . 
   On the other hand, when the group ID and the password are correct (Yes at step  103 ), the authentication processing unit  120  displays, at the requesting terminal, the menu screen  100   b  shown in  FIG. 8  (step S 104 ). When the user selects “edit menu” in the menu screen  100   b , the authentication processing unit  120  displays, at the requesting terminal, an address-book edit menu  100   c  shown in  FIG. 8 . When the user selects “new registration” in the address-book edit menu  100   c , the authentication processing unit  120  displays, at the requesting terminal, a registration form  100   d  shown in  FIG. 8  (step S 105 ). 
   When the user inputs registration information in the registration form  100   d , the edit processing unit  140  acquires the registration information (step S 106 ), registers the registration information in the subscriber-number management table  130   b  (step S 107 ), and determines whether the registration information includes a redial setting (step S 108 ). 
   When the registration information includes a redial setting (Yes at step S 108 ), the edit processing unit  140  sets “reserve” at the item of “redial” in the subscriber-number management table  130   b  (step S 109 ). When the registration information does not include a redial setting (No at step S 108 ), the edit processing unit  140  sets “disapproved” at the item of “redial” in the subscriber-number management table  130   b  (step S 110 ). 
   Accordingly, the authentication processing unit  120  authenticates user, and the edit processing unit  140  registers, in the subscriber-number management table  130   b , information input by the user at the registration form  100   d . Thus, the information is registered properly and efficiently. 
   At step S 104  in  FIG. 7 , when a user selects “change/delete” in the address-book edit menu  100   c , the edit processing unit  140  displays, at the requesting terminal, a change/delete screen  100   e  shown in  FIG. 9 . 
   When the user selects a user name from the change/delete screen  100   e  (user C is selected in  FIG. 9 ), the edit processing unit  140  displays a screen  100   f  shown in  FIG. 9  for changing information corresponding to the selected user. When the user changes the information, the edit processing unit  140  registers the information in the subscriber-number management table  130   b , and displays, at the requesting terminal, a change confirmation screen  100   g  shown in  FIG. 9 . 
     FIG. 10  is a flowchart of a processing procedure performed by the telephone-number management server  100  for generating a provisional number. When the authentication processing unit  120  receives a request to access the telephone-number management server  100  from the telephone terminal  10  or the IP telephone terminal  20 , the authentication processing unit  120  displays, at the requesting terminal, the authentication screen  100   a  shown in  FIG. 8  (step S 201 ). 
   When a user of the requesting terminal inputs a group ID and a password in the authentication screen  100   a , the authentication processing unit  120  acquires the group ID and the password (step S 202 ), determines whether the group ID and the password are correct by referring to the ID/password management table  130   a  (step S 203 ). When the group ID and the password are incorrect (No at step S 203 ), the system control returns to step S 201 . 
   On the other hand, when the group ID and the password are correct (Yes at step  203 ), the authentication processing unit  120  displays, at the requesting terminal, the menu screen  100   b  shown in  FIG. 8  (step S 204 ). When “address book/history” is selected in the menu screen  100   b , the authentication processing unit  120  displays, at the requesting terminal, an address-book/history screen  100   h  shown in  FIG. 11 . 
   When “address book” is selected in the address-book/history screen  100   h , the authentication processing unit  120  displays, at the requesting terminal, a list of registered users  100   i  shown in  FIG. 12  (step S 205 ). The Hyper Text Markup Language (HTML) of the list of registered users  100   i  is also shown in  FIG. 12 . 
   When the user selects a user name from the list of registered users  100   i , the user-group management unit  150  receives the selected user name (step S 206 ), acquires information corresponding to the selected user from the subscriber-number management table  130   b , and notifies the one-time-number management unit  160  of the user name (step S 207 ). 
   The one-time-number management unit  160  generates a provisional number (step S 208 ), and notifies the requesting terminal of the provisional number (step S 209 ). The one-time-number management unit  160  displays, at the requesting terminal, a notification screen  100   j  shown in  FIG. 13 , to notify the receiver&#39;s provisional number. 
   The HTML of the notification screen  100   j  is also shown in  FIG. 13 . An underlined description  100   k  in the HTML includes the receiver&#39;s provisional number. When the user of the requesting terminal selects “call” in the notification screen  100   j , the receiver&#39;s provisional number is automatically transmitted to the telephone-number management server  100 , so that the user can easily call the receiver. 
   Accordingly, the user-group management unit  150  displays the list of user names so that a caller selects a receiver&#39;s name. The one-time-number management unit  160  generates a provisional number corresponding to the selected user name, and transmits the provisional number to the caller&#39;s terminal. Thus, the caller can efficiently acquire the receiver&#39;s provisional number. 
     FIG. 14  is a flowchart of a processing procedure performed by the telephone-number management system for establishing a call. In  FIG. 14 , it is assumed that the telephone terminal  10  makes a request to call a receiver&#39;s telephone terminal. The exchange  50  receives a caller&#39;s regular number and a receiver&#39;s provisional number from the telephone terminal  10  (step S 301 ), and transmits an initial DP (including the caller&#39;s regular number and the receiver&#39;s provisional number) to the service control server  60  (step S 302 ). 
   The service control server  60  receives the initial DP from the exchange  50  (step S 303 ), transmits to the telephone-number management server  100  a provisional number conversion request to convert the receiver&#39;s provisional number to a regular number (step S 304 ), and the telephone-number management server  100  receives the request (step S 305 ). 
   The telephone-number management server  100  then performs a conversion processing to convert the receiver&#39;s provisional number to a regular number (step S 306 ), and sends a provisional number conversion response (i.e., the receiver&#39;s regular number) to the service control server  60  (step S 307 ). 
   The service control server  60  receives the provisional number conversion response (step S 308 ), and transmits converted data (i.e., the caller&#39;s regular number and the receiver&#39;s regular number) to the exchange  50  (step S 309 ). The exchange  50  receives the converted data (step S 310 ), and performs a processing to call the receiver&#39;s telephone terminal (step S 311 ). 
   Accordingly, a caller can call a receiver, without knowing the receiver&#39;s regular number, by requesting the receiver&#39;s provisional number from the telephone-number management server  100 , and using the provisional number to call the receiver. Moreover, the provisional number expires after a predetermined time duration to enhance security. 
   When the telephone-number management server  100  notifies a receiver of a caller&#39;s provisional number, the receiver can use the provisional number to redial the caller. When the telephone-number management server  100  notifies a receiver of a caller&#39;s identification data only, the receiver requests history information from the telephone-number management server  100  and uses the history information to redial the caller. 
   When the history-information management unit  170  receives a request to notify history information from a telephone terminal, the history-information management unit  170  displays, at the requesting terminal, an incoming-call register screen  1001  shown in  FIG. 15 . When a user selects a user name, the history-information management unit  170  requests the one-time-number management unit  160  to generate a provisional number corresponding to the selected user name, and transmits the provisional number to the requesting terminal. 
   When the telephone-number management server  100  receives a request to notify a receiver&#39;s provisional number from the telephone terminal  10 , the one-time-number management unit  160  generates a provisional number, and transmits the provisional number to the telephone terminal  10 . When the telephone-number management server  100  acquires a receiver&#39;s provisional number and a caller&#39;s regular number from the telephone terminal  10 , the one-time-number management unit  160  converts the receiver&#39;s provisional number to a regular number, and notifies the exchange of the caller&#39;s regular number and the receiver&#39;s regular number. Thus, leakage of personal information such as telephone numbers can be prevented while establishing telephone calls quickly and efficiently. 
   As described above, according to the present invention, it is possible to prevent a leakage of a telephone number, and at the same time, to make a call quickly. 
   Furthermore, according to the present invention, a caller can acquire a provisional number of a receiver efficiently. 
   Moreover, according to the present invention, a caller can improve a safety for a telephone number. 
   Furthermore, according to the present invention, a receiver can make a telephone communication with a caller efficiently. 
   Although the invention has been described with respect to a specific embodiment for a complete and clear disclosure, the appended claims are not to be thus limited but are to be construed as embodying all modifications and alternative constructions that may occur to one skilled in the art that fairly fall within the basic teaching herein set forth.