Abstract:
A communication apparatus for communicating with another apparatus via a network, includes: a storage unit for storing identification information of a plurality of networks and areas where the networks are deployed, respectively, and information of time periods while communication over the networks is permissible for the communication apparatus, respectively; a processor to control communication with the another apparatus in accordance with a process including: selecting one of the networks which is currently connectable and available to communicate with the another apparatus on the basis of the identification information of the networks and the areas; determining whether the present time is within one of the time periods; and either inhibiting communication with the another apparatus via the selected network when the present time is not within the period of time, or allowing communication with the another apparatus via the selected network when the present time is within the period of time.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This is a continuation of Application PCT/JP2007/057190, filed on Mar. 30, 2007, the entire contents of which are incorporated herein by reference. 
     
    
     FIELD 
       [0002]    A certain aspect of the embodiments discussed herein relates to a communication apparatus. 
       BACKGROUND 
       [0003]    With growing globalization, cellular phones in which roaming is enabled have come into use. International roaming in a cellular phone is performed by selecting and setting a country code (MCC: Mobile Country Code) and a network code (MNC: Mobile Network Code) stored in the cellular phone. This enables a user to, for example, make a call even overseas, using the user&#39;s information. 
         [0004]    However, for example, in a case where a cellular phone is stolen during an international roaming service, a problem such as damage including high charge for a call due to illegal use arises. 
         [0005]    Japanese Laid-open Patent Publication No. 2004-151772 discloses a roaming method for cellular phones. 
       SUMMARY 
       [0006]    According to an aspect of an embodiment, a communication apparatus for communicating with another apparatus via a network, the communication apparatus includes: a storage unit for storing identification information of a plurality of networks and areas where the networks are deployed, respectively, and information of time periods while communication over the networks is permissible for the communication apparatus, respectively; a processor to control communication with the another apparatus in accordance with a process including: selecting one of the networks which is currently connectable and available to communicate with the another apparatus on the basis of the identification information of the networks and the areas; determining whether the present time is within one of the time periods for the selected one of the networks; and either inhibiting communication with the another apparatus via the selected network when the present time is not within the period of time, or allowing communication with the another apparatus via the selected network when the present time is within the period of time. 
         [0007]    The object and advantages of the invention will be realized and attained by means of the elements and combinations particularly pointed out in the claims. 
         [0008]    It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are not restrictive of the invention, as claimed. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0009]      FIG. 1  is a hardware block diagram of a communication device  100  according to an embodiment. 
           [0010]      FIG. 2  is a functional block diagram of a USIM  110  according to the embodiment. 
           [0011]      FIG. 3  illustrates a user preferential network selection information file  300  according to the embodiment. 
           [0012]      FIG. 4  illustrates a mobile equipment number file  400  according to the embodiment. 
           [0013]      FIG. 5  illustrates a last time information file  500  according to the embodiment. 
           [0014]      FIG. 6  is a sequence diagram of writing IMEI according to the embodiment. 
           [0015]      FIG. 7  is a sequence diagram of setting time information according to the embodiment. 
           [0016]      FIG. 8  is a sequence diagram of updating time information according to the embodiment. 
           [0017]      FIG. 9  is a sequence diagram of registering user preferential network selection information according to the embodiment. 
           [0018]      FIG. 10  is a flowchart of an operation of reading roaming information according to the embodiment. 
           [0019]      FIG. 11  is a flowchart of selection in an operation of selecting PLMN according to the embodiment. 
           [0020]      FIG. 12  is a flowchart of an operation of updating a PLMN table according to the embodiment. 
           [0021]      FIG. 13  illustrates roaming information  1300  according to the 
       
    
    
     DESCRIPTION OF EMBODIMENTS 
       [0022]      FIG. 1  is a hardware block diagram of a cellular phone  100  according to an embodiment. 
         [0023]    In the embodiment, the description will be given, taking a cellular phone as an exemplary communication device. However, the communication device is not limited to a cellular phone and may be a communication device such as a personal digital assistant (PDA). 
         [0024]    The cellular phone  100  includes a micro processing unit (MPU)  101 , a storage unit (ROM/RAM)  102 , a transmitter and receiver unit (TRX)  103 , a display unit (Main-LCD/Sub-LCD)  104 , an audio processing unit (Audio)  105 , an operation unit (Key-pad)  106 , an HMI interface (HMI-I/F)  107 , a USB interface (USB I/F)  108 , a USIM interface (USIM I/F)  109 , a Universal Subscriber Identity Module (USIM)  110 , and a timer (TIMER)  111 . 
         [0025]    The MPU  101  performs various types of control of, for example, the storage unit  102 , the transmitter and receiver unit  103 , the display unit  104 , the audio unit  105 , and the operation unit  106 . The MPU  101  further controls reading data stored in an external device connected to the USB interface  108  and the USIM  110  and writing data to the USIM  110 . These control operations are performed by, for example, execution of a control program stored in a ROM included in the MPU  101 . In this case, a place where the control program is stored is not limited to a ROM and may be another recording medium equivalent to a ROM. In the embodiment, the cellular phone  100  includes, though not limited to, the single MPU  101 , and the MPU  101  performs overall control of the cellular phone  100 . For example, the cellular phone  100  may include another MPU in addition to the MPU  101 , the MPU  101  may perform communication control, and the other MPU may control applications installed in the cellular phone  100 . 
         [0026]    The storage unit  102  represents a ROM, a RAM, and the like as a whole and may include a detachable recording medium. The storage unit  102  may include, for example, a flash memory as a memory in which stored content is not lost even when the power is released. Moreover, application programs executable in the cellular phone  100  and the like are stored in the storage unit  102 , and the MPU  101  controls the cellular phone  100  by executing the application programs. 
         [0027]    The transmitter and receiver unit  103  transmits and/or receives radio beams through an antenna. The transmitter and receiver unit  103  generates radio beams to be transmitted and received by, for example, modulating and demodulating carrier signals that include signals expressing images, speech signals, dial signals, and the like. 
         [0028]    The display unit  104  includes, for example, liquid crystal display (LCD) elements and displays various types of input information and output information for the MPU  101 . In terms of hardware, the display unit  104  may include a plurality of LCDs. For example, the display unit  104  may include a main LCD and a sub LCD. 
         [0029]    The audio processing unit  105  includes a microphone and a speaker. The audio processing unit  105  converts analog audio signals captured from the microphone to digital signals and converts digital audio signals output from the MPU  101  to analog signals. The speaker is used to output, for example, audio signals output from the MPU  101  and audio signals captured through the microphone. 
         [0030]    The operation unit  106  includes a numeric keypad, a talk key, an end key, function keys, a cross key, and the like. A user can perform a call operation and operations of transmitting and receiving mails, using the operation unit  106 . Moreover, the MPU  101  controls the display unit  104 , the audio processing unit  105 , and the operation unit  106  via the HMI interface  107 . 
         [0031]    The USB interface  108  is used to connect to an external device. For example, the MPU  101  controls an external device a connection to which is established via the USB interface  108 . 
         [0032]    The USIM  110  is installed in the cellular phone  100  via the USIM interface  109 . The USIM  110  can be attached and detached to and from the cellular phone  100 . In the USIM  110 , for example, the telephone number of a user and information on a contracted carrier are recorded. The cellular phone  100  can be used by the use of user information such as a telephone number stored in the USIM  110  by attaching the USIM  110  to the cellular phone  100  by connecting the USIM  110  to the USIM interface  109 . 
         [0033]    The timer  111  implements a clock function and measures a time from set date and a set time. 
         [0034]      FIG. 2  is a functional block diagram of the USIM  110  according to the embodiment. 
         [0035]    The USIM  110  includes a storage area  201  and an MPU  202 . The telephone number, personal information, and the like of a user are stored in the storage area  201 . Moreover, the cellular phone  100  has a roaming function in which services by a contracted carrier can be received by the use of facilities of an overseas affiliate carrier. 
         [0036]    The storage area  201  of the USIM  110  stores roaming information  1300 , illustrated in  FIG. 13 , necessary for the cellular phone  100  to use a roaming function.  FIG. 13  illustrates the roaming information  1300  according to the embodiment. The roaming information  1300  includes a last time information file (EF_DATE)  500 , a mobile equipment number file (EF_IMEI)  400 , a home network selection information file (EF_HPLMNwAcT)  1303 , a user preferential network selection information file (EF_PLMNwAcT)  300 , a service information file (EF_UST)  1305 , a service authorization information file (EF_EST)  1306 , and a last registered network information file (EF_RPLMNAcT)  1307 . 
         [0037]    The last time information file  500  is information updated by the MPU  101  on the basis of a time measured by the timer  111 . The MPU  101  periodically updates a time  501  illustrated in  FIG. 5  on the basis of a time measured by the timer  111 . In this case, the USIM  110  does not have a clock function. Thus, the MPU  101  updates the last time information file  500  by periodically writing, to the USIM  110 , a time measured by the timer  111  installed in the cellular phone  100 . 
         [0038]    The mobile equipment number file  400  is information for identifying the cellular phone  100  and indicates a mobile equipment number  401 , as illustrated in  FIG. 4 . The cellular phone  100  also stores a mobile equipment number  1021  in the storage unit  102 . The MPU  101  reads the mobile equipment number file  400  from the storage area  201  and compares the mobile equipment number  1021  stored in the storage unit  102  with the mobile equipment number  401 . 
         [0039]    When the mobile equipment number  401  matches the mobile equipment number  1021 , the cellular phone  100  can be used by the use of user information such as a telephone number stored in the USIM  110 . When the mobile equipment number  401  does not match the mobile equipment number  1021 , the cellular phone  100  cannot be used by the use of, for example, a telephone number stored in the USIM  110 . User information may include, in addition to information on communication such as a telephone number and a mail address, a user name, address information, and the like set by a user. 
         [0040]    The home network selection information file  1303  is information in which a network code is in association with a country code, the network code indicating a network managed by an affiliate carrier that provides a roaming service predetermined by a carrier, the country code indicating a country where roaming is performed. In the home network selection information file  1303 , the priorities of pairs of country codes and network codes in association with the country codes are set. In this case, when roaming is performed by the use of the home network selection information file  1303 , the MPU  101  determines, in descending order of the priorities of the pairs, whether the pairs can be used. After the MPU  101  determines pairs of country codes and network codes that can be used, the MPU  101  performs roaming, using networks corresponding to the determined country codes and network codes. 
         [0041]    The user preferential network selection information file  300  illustrated in  FIG. 3  is information that can be set by a user and in which a country code  301 , a network code  302 , a usage start time  303 , a usage stop time  304 , and a priority  305  are in association with each other. A user can set the usage start time  303  and the usage stop time  304  in association with the country code  301  and the network code  302 . Roaming can be performed for an available period determined by the usage start time  303  and the usage stop time  304 , using a network corresponding to the network code  302 . Specifically, a network corresponding to a network code is a carrier network owned by an affiliate carrier that provides a roaming service. In the user preferential network selection information file  300  illustrated in  FIG. 3 , pairs of the country codes  301  and the network codes  302  are sorted in the order of the priorities used in roaming. The priorities can be properly set by a user. In the embodiment, both a network code that indicates a carrier network and a country code that indicates a country where roaming is performed are identification numbers but are not limited to numbers as long as the network code and the country code are character strings by which a network and a country can be identified. 
         [0042]    Moreover, a security lock is set on the usage start time  303  and the usage stop time  304  so that password authentication is required. A password and the like can be set by a user. Thus, since a user cannot change the usage start time  303  and the usage stop time  304  unless the user can enter a correct password, the usage start time  303  and the usage stop time  304  can be prevented from being illegally altered. The service information file  1305  is service information stored in the USIM  110  and is information that indicates an affiliate carrier that provides roaming. The service authorization information file  1306  is information on a service selected by the cellular phone  100 . The last registered network information file  1307  is information that indicates a network that was used the last time. 
         [0043]      FIG. 6  is a sequence diagram of writing the mobile equipment number  401  according to the embodiment. 
         [0044]    The cellular phone  100  requests the USIM  110  to register a password  61  and the mobile equipment number  401  (S 601 ). The USIM  110  registers the password  61  and the mobile equipment number file  400 , using the MPU  202  (S 602 ). After the USIM  110  completes the registration of the password  61  and the mobile equipment number file  400 , the USIM  110  transmits, to the cellular phone  100 , a completion notification that indicates the completion of registration of the password  61  and the mobile equipment number file  400  (S 603 ). 
         [0045]    The password  61  and the mobile equipment number  401  are stored in the storage area  201 . The password  61  registered in the USIM  110  by the cellular phone  100  is a password to be used to update the mobile equipment number file  400 . That is, when the mobile equipment number file  400  is updated, the MPU  202  authenticates the password  61 . When a password entered by a user matches the password  61 , the MPU  202  permits the mobile equipment number file  400  to be updated. 
         [0046]      FIG. 7  is a sequence diagram of setting the time  501  according to the embodiment. 
         [0047]    The cellular phone  100  requests the USIM  110  to register a password  71  and the time  501  (S 701 ). The USIM  110  sets the password  71  and the time  501 , using the MPU  202  (S 702 ). After the USIM  110  completes the registration of the password  71  and the last time information file  500 , the USIM  110  transmits, to the cellular phone  100 , a completion notification that indicates the completion of registration of the password  71  and the last time information file  500  (S 703 ). 
         [0048]    The password  71  is a password to be used to update the last time information file  500 . That is, when the last time information file  500  is updated, the MPU  202  authenticates the password  71 . When a password entered by a user matches the password  71 , the MPU  202  permits the last time information file  500  to be updated. 
         [0049]      FIG. 8  is a sequence diagram of updating time information according to the embodiment. 
         [0050]    The cellular phone  100  periodically transmits, to the USIM  110 , a time measured by the timer  111  to request the USIM  110  to update the time  501  (S 801 ). 
         [0051]    The USIM  110  updates the last time information file  500 , referring to the time that is measured by the timer  111  and is received from the cellular phone  100  (S 802 ). After the USIM  110  has updated the last time information file  500 , the USIM  110  transmits, to the cellular phone  100 , a completion notification that indicates that the last time information file  500  has been updated (S 803 ). 
         [0052]      FIG. 9  is a sequence diagram of registering the user preferential network selection information file  300  according to the embodiment. 
         [0053]    The cellular phone  100  requests the USIM  110  to register a password  91  and the user preferential network selection information file  300  (S 901 ). The USIM  110  registers the password  91  and the user preferential network selection information file  300 , using the MPU  202  (S 902 ). After the USIM  110  completes the registration of the password  91  and the user preferential network selection information file  300 , the USIM  110  transmits, to the cellular phone  100 , a completion notification that indicates the completion of registration of the password  91  and the user preferential network selection information file  300  (S 903 ). 
         [0054]    The password  91  is a password to be used to update the user preferential network selection information file  300 . That is, when the user preferential network selection information file  300  is updated, the MPU  202  authenticates the password  91 . When a password entered by a user matches the password  91 , the MPU  202  permits the user preferential network selection information file  300  to be updated. 
         [0055]      FIG. 10  is a flowchart of an operation of reading the roaming information  1300  according to the embodiment. 
         [0056]    The cellular phone  100  first reads the mobile equipment number file  400  stored in the USIM  110 . Then, the MPU  101  determines whether the mobile equipment number  1021  stored in the storage unit  102  matches the mobile equipment number  401  (S 1001 ). When the MPU  101  determines that the mobile equipment number  1021  does not match the mobile equipment number  401  (S 1001  NO), the cellular phone  100  terminates the operation of reading the roaming information  1300 . 
         [0057]    When the MPU  101  determines that the mobile equipment number  1021  matches the mobile equipment number  401  (S 1001  YES), the MPU  101  determines whether a time measured by the timer  111  is equal to or more than the time  501  in the last time information file  500  (S 1002 ). When the MPU  101  determines that the time measured by the timer  111  is smaller than the time  501  (S 1002  NO), the cellular phone  100  terminates the operation of reading the roaming information  1300 . 
         [0058]    When the MPU  101  determines that the time measured by the timer  111  is equal to or more than the time  501  (S 1002  YES), the MPU  101  performs the operation of reading the roaming information  1300  (S 1003 ). The operation of reading the roaming information  1300  is an operation of the cellular phone  100  selecting a network in which roaming is performed and the like on the basis of country information and position information obtained from a base station and the like so as to perform roaming. Thus, the cellular phone  100  can perform roaming communication via a set network. In the reading operation, an operation of selecting the user preferential network selection information file  300  illustrated in  FIG. 11  can also be performed. 
         [0059]      FIG. 11  is a flowchart of an operation of selecting the user preferential network selection information file  300  according to the embodiment. 
         [0060]    The MPU  101  refers to the last registered network information file  1307  stored in the USIM  110  (S 1101 ). Then, the MPU  101  refers to the service information file  1305  and the service authorization information file  1306  (S 1102 ). Then, the MPU  101  determines whether the user preferential network selection information file  300  is registered (S 1103 ). 
         [0061]    When the MPU  101  determines that the user preferential network selection information file  300  is registered (S 1103  YES), the MPU  101  selects a network in which roaming can be performed in response to the priorities of networks described in the user preferential network selection information file  300  (S 1105 ). 
         [0062]    When the MPU  101  determines that the user preferential network selection information file  300  is not registered (S 1103  NO), the MPU  101  determines whether the home network selection information file  1303  is registered (S 1104 ). When the home network selection information file  1303  is registered (S 1104  YES), the home network selection information file  1303  is selected, and a network in which roaming can be performed is selected in response to the priorities of networks described in the home network selection information file  1303  (S 1106 ). 
         [0063]    When the MPU  101  determines that the home network selection information file  1303  is not registered (S 1104  NO), the MPU  101  terminates the operation without selecting any network in which roaming is performed. 
         [0064]      FIG. 12  is a flowchart of an operation of updating the user preferential network selection information file  300  according to the embodiment. 
         [0065]    The MPU  202  creates the user preferential network selection information file  300  on the basis of input from the operation unit  106  and the like (S 1201 ). Then, the MPU  101  determines whether the cellular phone  100  is located outside a service area (S 1202 ). For example, it is determined whether the transmitter and receiver unit  103  can receive position information and the like from a base station and the like to determine whether the cellular phone  100  is located outside the service area. 
         [0066]    When the MPU  101  determines that the cellular phone  100  is not located outside the service area (S 1202  NO), the MPU  101  determines whether a time measured by the timer  111  is within an available period of a network selected to perform roaming (S 1203 ). When the MPU  101  determines that the time measured by the timer  111  is within the available period of the network selected to perform roaming (S 1203  YES), the MPU  101  again determines whether the cellular phone  100  is located outside the service area (S 1202 ). When the time measured by the timer  111  is not within the available period of the network selected to perform roaming (S 1203  NO), the MPU  202  re-creates the user preferential network selection information file  300  ( 51204 ). Thus, the MPU  202  can determine, by reading the last time information file  500  and the user preferential network selection information file  300  from the storage area  201  and comparing the last time information file  500  with the user preferential network selection information file  300 , whether the network to be used for roaming can be used. 
         [0067]    When the MPU  101  determines that the cellular phone  100  is located outside the service area (S 1202  YES), the cellular phone  100  waits until the cellular phone  100  comes into the service area (S 1205 ). Then, the MPU  101  determines whether the time measured by the timer  111  is within the available period of the network selected to perform roaming (S 1206 ). When the MPU  101  determines that the time measured by the timer  111  is not within the available period of the network selected to perform roaming (S 1206  NO), the MPU  101  restarts the operation of selecting the user preferential network selection information file  300  ( 51207 ). Then, the MPU  202  re-creates the user preferential network selection information file  300  (Sl 204 ). When the MPU  101  determines that the time measured by the timer  111  is within the available period of the network selected to perform roaming (S 1206  YES), the MPU  101  again determines whether the time measured by the timer  111  is within the available period of the network selected to perform roaming (S 1206 ). 
         [0068]    An operation performed by selecting means according to the present invention is included in operations performed by the MPU  101  in the embodiment. Moreover, an operation performed by determining means according to the present invention is included in the operations performed by the MPU  101  in the embodiment. Moreover, an operation performed by communicating means according to the present invention is included in operations performed by the transmitter and receiver unit  103  in the embodiment. Moreover, an operation performed by storing means according to the present invention is included in operations performed by the storage area  201  according to the embodiment. Moreover, identification information in the present invention corresponds to the mobile equipment number file  400  in the embodiment. 
       INDUSTRIAL APPLICABILITY 
       [0069]    A communication device according to the present invention sets an available period of a network used to communicate with another communication device. Thus, the communication device according to the present invention is extremely useful in performing communication in a cellular phone that has a roaming function. 
         [0070]    All examples and conditional language recited herein are intended for pedagogical purposes to aid the reader in understanding the invention and the concepts contributed by the inventor to furthering the art, and are to be construed as being without limitation to such specifically recited examples and condition, nor does the organization of such examples in the specification relate to a showing of superiority and inferiority of the invention. Although the embodiment of the present inventions have been described in detail, it should be understood that the various changes, substitutions, and alternations could be made hereto without departing from the spirit and scope of the invention.