JP4830516B2 - Communications system - Google Patents

Description

The present invention relates to a communication system.

  In recent years, with the spread of digital cameras and camera-equipped mobile phones, electronic files such as images taken by individuals are often transmitted and received via a network. At the same time, with the expansion of the network environment, there is a problem that electronic files leak on the network against the intentions of the photographer and the photographed person.

  In this way, there are data protection and viewing restrictions (copy once etc.) of digital content created by professionals as countermeasures against the leakage of electronic files on the network, but digital content created by general users There is no data protection or browsing restriction mechanism in place.

On the other hand, there already exists a technique for embedding personal information in an electronic file, that is, an image taken with a digital camera or the like, or an electronic file including any other kind of digital content. There is also a technique for reading such an electronic file (see, for example, “Patent Document 1”).
JP-A-2005-71054

  However, even if the personal information is read and the creator of the electronic file can be identified, if the electronic file itself leaks onto the Internet, there is a risk that the unspecified number of third parties will be able to view the file. Still exists.

The present invention has been made in view of the above problems, it is an object of the present invention is to provide a communication system that can browse restriction data.

In order to achieve the above-described object, the first invention is a communication system that performs communication between a plurality of portable terminals, wherein the first portable terminal includes personal information that identifies the first portable terminal, Communication means for communicating the authentication information including the key unique to the portable terminal to the second portable terminal without going through the server, and the second portable terminal is sent from the first portable terminal. has a holding means for holding the authentication information and the personal information, the first mobile terminal encrypts the data with the key, the signal means transmission to be transmitted to the second mobile terminal via the server The second mobile terminal, when data is sent from the first mobile terminal via a server, means for extracting authentication information including a key related to the first mobile terminal from the holding means; anda means for decoding the data in the key, the first The portable terminal has means for adding, to the data, second authentication information that identifies a creator when the data is generated, and the data to which the second authentication information is added is the second data The second portable terminal has a means for comparing the data creator and the owner of the second portable terminal, and prohibiting the transfer of the data if they do not match. This is a featured communication system.

  The first portable terminal has means for adding a copy limit count to the data when generating the data, and the data to which the copy limit count is added is sent to the second portable terminal. The second portable terminal has means for reducing the copy limit count by “1” when storing the data.

The communication means is infrared communication.

According to the present invention, it is possible to provide a communication system capable of data viewing restrictions.

  Hereinafter, a communication system (electronic file protection system) 100 according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a block diagram showing the configuration of the electronic file protection system 100. As shown in FIG. 1, the electronic file protection system 100 is configured by connecting a mail server 109 and a plurality of mobile terminals 101 a, 101 b, 101 c, etc. via a network 107. The portable terminals 101a, 101b, and 101c are owned by the user A 103a, the user B 103b, and the user C 103c, respectively.

  The mobile terminal 101 is a mobile phone (particularly the third generation 3GPP), a set-top box (STB) that is a receiving device for analog TV or digital TV, an in-vehicle terminal that is a position signal transmission / reception device such as an in-vehicle guide device or GPS. is there.

  Each portable terminal 101 includes a display unit 203, an input unit 206, and the like, and is operated by the user 103. The portable terminal 101 is equipped with a plug-in type IC card 110 and holds data such as an address book 330.

  The network 107 is a network such as the Internet or a local area network (LAN), and may be wired or wireless.

  The mail server 109 is a server computer or the like, and is a server that manages mail transmission / reception in the portable terminal 101. The mail server 109 is provided by the service provider of the mobile terminal 101.

  Next, the hardware configuration of the mobile terminal 101 will be described with reference to FIG. FIG. 2 is a hardware configuration diagram of the mobile terminal 101. Only the components related to the present invention are illustrated, and the transmission / reception unit and the like are not illustrated.

  The portable terminal 101 includes a control unit 201, a storage unit 202, a display unit 203, a camera 204, a transmission / reception unit 205, an input unit 206, a microphone 207, a recording medium I / F unit 208, an encryption / decryption circuit 209, and an infrared communication unit 210. The antenna 211 and the like are connected and configured via the bus 212.

  The control unit 201 includes a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and the like.

The CPU calls the program stored in the storage unit 202, ROM, encryption / decryption circuit 209, recording medium such as the IC card 220 or memory card 230, etc., into the work memory area on the RAM and executes it via the system bus. The various devices connected to each other are driven and controlled to implement various processes performed by the mobile terminal 101.
The ROM is a non-volatile memory and permanently holds a computer boot program, a program such as BIOS, data, and the like.
The RAM is a volatile memory, and temporarily stores a program, data, and the like loaded from the storage unit 202, ROM, recording medium, and the like, and includes a work area used by the control unit 201 for performing various processes.

The storage unit 202 stores a program executed by the control unit 201, data necessary for program execution, an OS (operating system), and the like.
Each of these program codes is read by the control unit 201 as necessary, transferred to the RAM, read by the CPU, and executed as various means.

  The display unit 203 is a display device such as a CRT monitor or a liquid crystal panel. The camera 204 acquires image data, video data, and the like.

  The transmission / reception unit 205 is a communication interface that mediates communication between the mobile terminal 101 and the network 107, and controls communication between the mail server 109 and the mobile terminal 101 via the network 107. The transmission / reception unit 205 is connected to the antenna 211.

  The input unit 206 inputs data and is an input device such as a keyboard or a numeric keypad. The microphone 207 acquires audio data.

The recording medium I / F unit 208 exchanges data with the recording medium. The recording medium is an IC card 220, a memory card 230, or the like.
The encryption / decryption circuit 209 decrypts the encrypted data and encrypts the data.

  The infrared communication unit 210 performs infrared communication. The infrared communication unit 210 performs processing such as converting received infrared light into a control signal. Infrared communication is performed without going through the mail server 109. In addition to infrared rays, other short-range wireless communication systems using electromagnetic waves, ultrasonic waves, or the like may be used.

FIG. 3 is a diagram showing the IC card 110.
As shown in FIG. 3, the IC card 110 is a contact type IC card, and performs power supply and communication when the IC module terminal and the reader / writer terminal come into contact with each other.
The IC card 110 includes a CPU 301, a ROM 303, a RAM 305, an EEPROM 307 (Electrically Erasable Programmable ROM), and the like.

  The ROM 303 has a program area 309 and stores a platform-type OS 360 that can add and delete applications. A part of the application program is stored. A protection application program 350 and the like in the electronic file protection system 100 are stored.

The EEPROM 307 has a user area and can mount a plurality of applications corresponding to the platform type OS. For example, an authentication application program for authenticating a contract terminal and authentication information (for example, contractor identification information) for specifying a valid user / terminal are mounted and stored as applications. Further, an address book 330, user data 340, and the like are stored.
The IC card 110 is not limited to this configuration.

  Next, the personal information data 310 in the portable terminal 101 will be described with reference to FIG. FIG. 4 is a diagram showing an aspect of the personal information data 310. The personal information data 310 is data stored in the IC card 110 of the portable terminal 101 and transmitted / received between the users 103 via the infrared communication 105. Personal information data 310 is received from the mobile terminal 101 of another user 103, input via the infrared communication unit 210, and stored in the address book 330.

The electronic certificate 311 is identification information unique to each mobile terminal 101. An encryption key 314 and an IMSI (International Mobile Subscriber Identity) 315 are included. The encryption key 314 is data used when the user 103 who owns the mobile terminal 101 encrypts an electronic file created by the user 103. That is, the user A 103a encrypts the image data taken by the user A 103a in the portable terminal 101 and transmits it to the user B 103b. At this time, the encryption key 314 is used. The user B 103b can refer to the user B 103b only after decrypting the electronic file received by the portable terminal 101b with the same encryption key 314. The IMSI 315 is a subscriber identification number and is a number unique to each user of the mobile terminal. That is, the IMSI 315 is a number set for each IC card 110 of the mobile terminal 101.

  In the electronic file protection system 100, the electronic certificate 311 is also used when specifying the creator of the electronic file, that is, the portable terminal 101 that has captured and acquired the image data.

  The telephone number 312 is the telephone number of the mobile terminal 101, and the mail address 313 is the mail address of the mobile terminal 101. The personal information data 310 can include arbitrary data such as the name of the user 103 in addition to the electronic certificate 311, the telephone number 312, and the mail address 313.

Next, the transmission data 320 will be described with reference to FIG. FIG. 5 is a diagram illustrating an aspect of the transmission data 320.
The transmission data 320 indicates transmission contents when transmitting data such as image data.
The transmission data 320 is created with reference to the address book 330 and the user data 340 and is transmitted to the other portable terminal 101 via the mail server 109.
The transmission destination electronic certificate 321 is an electronic certificate of the counterpart portable terminal 101 to which the user data 340 is to be transmitted. From the address book 330, an electronic certificate 602 corresponding to the user 601 is referenced and added.

The electronic certificate 322 is the same as the electronic certificate 311 in FIG. 4 and is included in the user data 340. That is, it is identification information held by the creator of the data portion 325 to be transmitted, that is, the photographer of the image data.
The number of copies 323 is the number of copies permitted for the data part 325 to be transmitted.
The specific user 324 is an ID of a user who is permitted to browse the data part 325 to be transmitted. For the specific user 324, IMSI may be used, or an e-mail address or a telephone number may be used.

  The data part 325 is data of digital content such as an image or video to be transmitted. At the time of transmission, encryption is performed by the transmitting portable terminal 101.

  Next, the address book 330 will be described with reference to FIG. FIG. 6 is a diagram illustrating an aspect of the address book 330. The address book 330 is held in the IC card 110 of the mobile terminal 101. Data in the address book 330 is acquired by input from the user 103 or by receiving data from another portable terminal 101 by infrared communication.

The user 601 is information for identifying the user 103 as a transmission destination. The electronic certificate 602 is information such as the encryption key and IMSI of the mobile terminal 101 corresponding to the user 601. When the electronic certificate 602 is included in the address book 330, it is limited to the user 103 who has acquired the personal information data 310 by the infrared communication 105.
A telephone number 603 is a telephone number corresponding to the user 601, and a mail address 604 is a mail address corresponding to the user 601.
The data items included in the address book 330 are not limited to this configuration.

  Next, the user data 340 will be described with reference to FIG. FIG. 7 is a diagram showing an aspect of user data 340. User data 340 is held in the IC card 110 of the mobile terminal 101. The acquisition of the user data 340 is performed when shooting is performed by the camera 204 or when data transmitted from another mobile terminal 101 is received.

  ID 701 is an ID for identifying data. An attribute 702 indicates the type of data in the data portion 325. The copy count 323 and the specific user 324 are the same as the copy count 323 and the specific user 324 in FIG. The electronic certificate 322 is information for identifying the creator of the corresponding data. This is the same as the electronic certificate 322 in FIG. A data portion 325 indicates digital content itself such as image data, music data, and video data, and is the same as the data portion 325 in FIG.

Next, with reference to FIG. 8, an operation when the personal information data 310 is transmitted from the mobile terminal 101a to the mobile terminal 101b will be described. FIG. 8 is a flowchart showing operations of the mobile terminal 101a and the mobile terminal 101b.
For example, this is an operation when user A 103a and user B 103b use each other's portable terminal 101 to exchange information such as a telephone number.

  First, the control unit 201 of the mobile terminal 101a adds the electronic certificate 311 of the mobile terminal 101a to personal information data such as a mail address, generates personal information data 310, and transmits the personal information data 310 via the infrared communication unit 210. It transmits to the portable terminal 101b (step 801).

  The control unit 201 of the mobile terminal 101b writes the personal information data 310 received from the mobile terminal 101a to the address book 330b (step 802).

  As described above, when the personal information data 310 is exchanged using both the mobile terminals 101 that transmit and receive, the electronic certificate 311 is added in addition to the information such as the telephone number 312 and the mail address 313. An electronic certificate 311 is stored in the address book 330 of the mobile terminal 101 of the transmission destination.

  Specifically, a case where the user A 103a and the user B 103b know each other and exchange addresses with each other is taken as an example. The user A 103 a performs an operation for transmitting to the user B 103 b his / her profile stored in his / her portable terminal 101 a, that is, information such as the telephone number 312 and the mail address 313 via the infrared communication 105. Then, the control unit 201 of the portable terminal 101 a adds the electronic certificate 311 and transmits it as personal information data 310.

  Similarly, the user B 101b performs an operation for sending the profile stored in the mobile terminal 101b to the mobile terminal 101b. The personal information data 310 transmitted / received to / from each other includes an electronic certificate 311. In the address book 330a of the portable terminal 101a, an electronic certificate 602 is stored in addition to the telephone number 603 and the mail address 604 as information of the user B 103b. This electronic certificate 602 is used when decrypting an encrypted electronic file sent from the portable terminal 101b.

  Similarly, the electronic certificate 602 of the user A 103a is stored in the address book 330b of the mobile terminal 101b of the user B 103b. As described above, this electronic certificate 602 is used when decrypting an encrypted electronic file sent from the portable terminal 101A.

  As described above, the electronic certificate 602 is stored in the address book 330 only for the other user 103 who is actually acquainted and directly received the personal information data 310.

  Next, an operation when saving the user data 340 will be described with reference to FIG. FIG. 9 is a flowchart showing the operation of the mobile terminal 101a in the storage of the user data 340 from the acquisition of the data part 325.

  First, the control unit 201 of the mobile terminal 101a acquires the data unit 325 (step 901). The data unit 325 is acquired by photographing with the camera 204 of the portable terminal 101a, inputting music data using a music creation tool, or the like.

  The user A 103a who acquired the data part 325, that is, the owner of the portable terminal 101a performs an operation for storing the acquired data part 325 in the user data 340a. At this time, the number of copying, the transmission destination, etc. are arbitrarily specified and saved. This information is input from the input unit 206. The control unit 201 adds the number of copies 323 received from the input unit 206, input items such as the specific user 324, and the electronic certificate 332 of the portable terminal 101a, and writes them to the user data 340a in the IC card 110 (step 902). ).

  In addition, the data included in the user data 340 includes data transmitted from other mobile terminals 101 and data downloaded from a public web site. Other than the data created by the user, the electronic certificate 322 of the portable terminal 101 of the creator other than the user is added. Some do not include the electronic certificate 322.

  In addition, if the user A 101a has acquired the data portion 325, that is, the photographer of the image data, the contents of the user data 340a may be changed only by an operation on his / her mobile terminal 101a. That is, for example, a user interface that allows the specific user 324 to be added or the number of copies 323 to be changed at a later date after the shooting date can be provided. In this case, in order to further increase the security of the user data 340, a password function may be provided so that a third party does not change the attribute using the mobile terminal 101a.

  Next, processing when an electronic file is transmitted from the mobile terminal 101a to the mobile terminal 101b will be described with reference to FIGS. 10, 11 and 12. FIG. FIG. 10 shows the operation of the portable terminal 101a accompanying the transmission of the user data 340a.

  First, the control unit 201 refers to the electronic certificate 322 of the user data 340 to be transmitted (step 1001). The electronic certificate 322 is information of a creator of the data portion 325 of the user data 340, for example, a photographer in the case of image data such as a photograph. Next, it checks whether the electronic certificate 322 belongs to the portable terminal 101a to be transmitted (step 1002). The IMSI in the IC card 110 of the portable terminal 101a is referred to and compared with the IMSI of the electronic certificate 322 to check whether they match. That is, it is verified whether the user data 340 to be transmitted is data created by itself.

  If the electronic certificate 322 is not from the portable terminal 101a (No in Step 1002), the control unit 201 outputs an error message (Step 1003) and immediately ends the process. This means that the electronic file created by the user A 103a, for example, the user A 103a cannot be transmitted unless the image data is captured using the camera 204 of the mobile terminal 101.

  If the electronic certificate 322 belongs to itself, that is, the portable terminal 101a (Yes in Step 1002), the control unit 201 then refers to the copy count 323 of the user data 340a (Step 1004). By checking the number of copies 323, copying is not performed beyond the permitted number of copies. If the number of copies 323 is 0 (No in Step 1005), the control unit 201 outputs an error message (Step 1006) and immediately ends the process.

  If the number of times of copying 323 is greater than 0 (Yes in Step 1005), the control unit 201 collates the user 601 to be transmitted from the address book 330a with the specific user 324 in the user data 340a (Step 1007). ). In the verification step, first, the control unit 201 acquires the transmission destination user 601 designated by the user A 103a. Next, the specific user 324 of the user data 340a to be transmitted is acquired and compared. When a plurality of users 103 are designated as the specific user 324, it is checked whether or not the transmission destination user 601 is included therein. That is, it is checked whether or not the destination user 103 to be transmitted matches the transmission target user 103 set when the user data 340 is saved.

When the user 601 and the specific user 324 do not match (No in Step 1008), the control unit 201 outputs an error message (Step 1009) and immediately ends the process.

  When the user 601 and the specific user 324 match (Yes in Step 1008), the control unit 201 decrements the count of the copy count 323 of the user data 340 by 1 (Step 1010). Next, the control unit 201 starts transmission processing (step 1011).

Note that the error messages in step 1003, step 1006, and step 1009 are displayed on the display unit 203 of the mobile terminal 101.
FIG. 12 shows an aspect of the screen display of the error message 1201. The error message 1201 displays a message indicating a transmission failure such as “cannot be transmitted” and a reason 1202 for the transmission failure. For example, as shown in step 1009, when the user data 340 is to be transmitted to the mobile terminal 101 other than the specific user 324, a display such as “This data cannot be transferred to a third party” is displayed as shown in FIG. Do.

  The inspections in step 1002, step 1005, and step 1008 in FIG. 10 are performed according to the setting of the user data 340, and are not performed for those that are not set. For example, if the number of copies 323 is not set, the processing in step 1004 and step 1005 is not executed.

  FIG. 11 is a flowchart showing operations of the mobile terminal 101a and the mobile terminal 101b in the transmission process (step 1011 in FIG. 10).

  First, the control unit 201 of the mobile terminal 101a adds the electronic certificate 602 of the transmission destination in the address book 330 to the user data 340, encrypts it with the encryption key of the electronic certificate 322 of the mobile terminal 101a, and transmits the transmission data. 320 (step 1101).

  Next, the control unit 201 transmits the transmission data 320 to the portable terminal 101b of the transmission destination user B 103b (step 1102).

  The control unit 201 of the mobile terminal 101b receives the transmission data 320 sent from the mobile terminal 101a (step 1103).

  The control unit 201 of the portable terminal 101b refers to the address book 330b and performs authentication using the encryption key (step 1104). That is, the data of the transmission source user A 103a is read from the address book 330b with reference to the electronic certificate 602 of the data, and the encryption key information in the electronic certificate is read. It authenticates whether or not the encryption key of the electronic certificate 602 included in the address book 330b is an encryption that can decrypt the transmission data 320 transmitted from the mobile terminal 101a.

  When the authentication with the encryption key fails (No in Step 1105), the control unit 201 invalidates the content of the transmission data 320 (Step 1106) and ends the process. That is, only the transmission data 320 from the portable terminal 101 whose electronic certificate has been exchanged in advance can be decrypted and read.

  When the authentication with the encryption key is successful (Yes in Step 1105), the control unit 201 decrypts the transmission data 320 transmitted from the mobile terminal 101a and stores it in the user data 340 of the mobile terminal 101b (Step 1107). ).

  As described above, the sender's portable terminal 101a refers to the creator's electronic certificate 322, copy count 323, specific user 324, etc. of the user data 340, and may be transmitted to the portable terminal 101b. After that, the transmission data 320 is created and transmitted to the portable terminal 101b. The receiver's portable terminal 101b performs cryptographic authentication. If the authentication is successful, the transmission data 320 from the portable terminal 101a can be referred to.

  Therefore, if the mobile terminals 101 of the transmission source and the transmission destination of an electronic file including digital content such as image data do not exchange personal information with each other using an electronic certificate, execution of transmission / reception of the electronic file is limited. The As a result, the electronic file created by the user is not transferred to a third party.

  In addition, when an electronic file is created, that is, when an image is captured and saved, arbitrary viewing restrictions can be added, so transfer restrictions and user restrictions can be changed depending on the type of electronic file. is there.

  Specifically, the user B 103b that has received the transmission data 320 including the image data from the user A 103a is restricted from transmitting the transmission data 320 to another user, for example, the user C. For example, it is assumed that the image data transmitted from the mobile terminal 101a is stored in the user data 340b of the mobile terminal 101b. The photographer is the user A 103a himself. The electronic certificate 322 includes the IMSI and encryption key of the mobile terminal 101a. If the user B 101b tries to transmit to the user C 101c, the electronic certificate 322 of the user data 340 does not belong to the portable terminal 101b of the user B 101b, so an error occurs in the process of step 1002 in FIG.

  For example, even if the user B 103b who is not a photographer is given permission to transfer the user data 340, the user B 103b cannot perform browsing on the portable terminal 101 that does not have the electronic certificate of the portable terminal 101b by encryption. In this way, it is possible to perform multiple checks regarding transfer and browsing.

Further, by using the number of copies 323 of the user data 340 as a counter, the number of copies can be limited.
For example, the user A 103a takes an image, designates the number of copies 323 in the user data 340, and saves it. The data is transmitted to the user B 103b. When the first copy count 323 is set to “1”, as shown in Step 1011 of FIG. 10, the copy count 323 is decremented by “1” during transmission and becomes “0”. Next, when the user A 103a tries to transmit the data to the other user 103, the copy count 323 is 0, so an error occurs in step 1005.

  In addition, even when data is copied to a device other than the portable terminal 101 via a recording medium or via a cable, the copy count 323 is similarly used as a counter to prevent unlimited copying of user data 340. Can do.

  The preferred embodiments of the communication system and the like according to the present invention have been described above with reference to the accompanying drawings, but the present invention is not limited to such examples. It will be apparent to those skilled in the art that various changes or modifications can be conceived within the scope of the technical idea disclosed in the present application, and these are naturally within the technical scope of the present invention. Understood.

The block diagram which shows the structure of the electronic file protection system 100 Hardware configuration diagram of portable terminal 101 The figure which shows the one aspect | mode of the data structure of IC card 110 The figure which shows the one aspect | mode of the personal information data 310 The figure which shows the one aspect | mode of the transmission data 320 The figure which shows the one aspect | mode of the address book 330 The figure which shows the one aspect | mode of the user data 340 Flow chart showing operation of personal information data 310 transmission processing Flowchart showing operation of user data 340 write processing Flow chart showing operation of pre-transmission processing of user data 340 The flowchart which shows the operation | movement of the transmission process of the transmission data 320. Figure showing an aspect of the error message

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 ......... Electronic file protection system 101 ......... Mobile terminal 103 ......... User 110 ......... IC card 201 ......... Control part 202 ......... Storage part 203 ......... Display part 204 ......... Camera 205 ... Transmission / reception unit 206 ... Input unit 207 Microphone 208 Recording medium I / F unit 209 Encryption / decryption circuit 210 Infrared communication unit 211 ... Antenna 213 Memory card

Claims (3)

A communication system for performing communication between a plurality of portable terminals,
The first mobile terminal
Communication means for communicating personal information for identifying the first portable terminal and authentication information including a key unique to the first portable terminal to the second portable terminal without using a server;
The second mobile terminal
Holding means for holding the personal information and the authentication information sent from the first portable terminal;
The first portable terminal is
Encrypts data with the key has a signal means transmission to be transmitted to the second mobile terminal via the server,
The second portable terminal is
Means for extracting authentication information including a key relating to the first portable terminal from the holding means when data is sent from the first portable terminal via a server; and means for decrypting the data with the key;
Equipped with,
The first portable terminal is
Means for adding, to the data, second authentication information for identifying a creator when generating the data;
The data to which the second authentication information is added is sent to the second mobile terminal,
The second mobile terminal compares the data generator with the owner of the second mobile terminal, and has a means for prohibiting transfer of the data if they do not match . The first portable terminal is
Means for adding a copy limit number to the data when generating the data;
The data with the copy limit number added is sent to the second mobile terminal,
The communication system according to claim 1, wherein the second portable terminal has means for reducing the copy limit count by “1” when storing the data. Said communications means includes communications system according to claim 1, characterized in that an infrared communication.

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