JP2004094539A - Mobile communication terminal, and method of transceiving information - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enhance security for transmission and reception of an electronic value. <P>SOLUTION: In this mobile communication terminal 20, a secret key and an enciphering program for a user requiring secrecy are stored in an UIM 28. Those data are stored in the UIM 28 to secure the sufficient secrecy about the data requiring the secrecy. The other data (for example, acoustic data) is stored properly in the UIM28 in response to a data volume and a required level of the secrecy to transmit and receive the electronic value safely to/from gate equipment (for example, automatic ticket gate) 40 communicatable with the mobile terminal 20 of the present method. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a mobile communication terminal and an information transmitting / receiving method.
[0002]
[Prior art]
In recent years, research on electronic value represented by electronic money has been actively conducted. As part of the research, the electronic value (e.g., an automatic ticket gate, etc.) in cooperation with the mobile communication terminal storing the electronic value information and a destination terminal capable of communicating with the mobile communication terminal (e.g., an automatic ticket gate). For example, a technique for opening a gate of an automatic ticket gate by giving and receiving an electronic ticket has been studied, and such a technique is disclosed in, for example, JP-A-2002-133455. This publication takes measures against leakage of electronic value information by attaching an electronic signature to the electronic value at the time of transmitting and receiving the electronic value by the two-party communication between the portable communication terminal and the destination terminal.
[0003]
[Problems to be solved by the invention]
In order to effectively prevent the leakage of electronic value information, the service provider who manages the electronic value flow system manages the electronic value information, and not only the mobile terminal that has easy security but also the mobile terminal that many users possess. It is necessary to take measures for information leakage in communication terminals. However, in the portable communication terminal disclosed in the above publication, information leakage is prevented only by attaching a user's electronic signature to the electronic value. Therefore, when a so-called user secret key for creating an electronic signature is stolen, an electronic value with an illegally created electronic signature is exchanged as a legitimate electronic value with a destination terminal. It is possible.
[0004]
The present invention has been made to solve the above-described problem, and has as its object to provide a mobile communication terminal and an information transmission / reception method in which the security of electronic value transfer is improved.
[0005]
[Means for Solving the Problems]
The portable communication terminal according to the present invention includes a tamper-resistant memory having tamper resistance, attaches an electronic signature to an electronic value using a user's private key, and sends the electronic value with the electronic signature to a destination terminal. A portable communication terminal that transmits to the destination terminal and performs a process corresponding to the electronic value to the destination terminal. The tamper-resistant memory stores a user's secret key and an electronic signature using the user's secret key. An encryption program to be created is stored.
[0006]
In this portable communication terminal, a tamper-resistant memory stores a secret key and an encryption program of a user who requires confidentiality. By storing these data in the tamper-resistant memory, sufficient confidentiality can be ensured for data requiring confidentiality. Then, other data (for example, voice data) is stored in a tamper-resistant memory as appropriate according to the data capacity and the required level of confidentiality, so that an automatic ticket gate capable of communicating with the mobile communication terminal according to the present invention is provided. Electronic value can be safely exchanged with a counterpart terminal such as a machine or a POS register.
[0007]
An information transmitting / receiving method according to the present invention includes a tamper-resistant memory having tamper resistance, and attaches an electronic signature to an electronic value using a secret key of a user, and transmits the electronic value with the electronic signature to a destination terminal. An information transmission / reception method using a mobile communication terminal that transmits to a destination terminal and performs a process corresponding to the electronic value, wherein the secret key of the user is stored in a tamper-resistant memory of the mobile communication terminal. And an encryption program for creating an electronic signature using the secret key.
[0008]
In this information transmission / reception method, a secret key and an encryption program of a user who requires confidentiality are stored in the tamper-resistant memory. By storing these data in the tamper-resistant memory, sufficient confidentiality can be ensured for data requiring confidentiality. Then, other data (for example, voice data) is stored in a tamper-resistant memory as appropriate according to the data capacity and the required level of confidentiality, so that an automatic ticket gate capable of communicating with the mobile communication terminal according to the present invention is provided. Electronic value can be safely exchanged with a counterpart terminal such as a machine or a POS register.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, preferred embodiments of a portable communication terminal and an information transmitting / receiving method according to the present invention will be described in detail with reference to the accompanying drawings.
[0010]
First, a first embodiment of the portable communication terminal according to the present invention will be described. As shown in FIG. 1, a communication system 10 according to the first embodiment includes a service provider device 12, a mobile communication terminal 20, and a gate device (a destination terminal) 40. The service provider device 12 is connected to the Internet 14, and the mobile communication terminal 20 and the gate device 40 are also connectable to the Internet 14. The mobile communication terminal 20 and the gate device 40 (for example, an automatic ticket gate) communicate by wire, wireless communication (for example, Bluetooth, IrDA, or the like), or non-contact communication. The communication system 10 is mainly intended for a mode in which a user of the terminal 20 opens a gate (not shown) of the gate device 40 using an electronic value (for example, an electronic ticket) stored in the mobile communication terminal 20. It is a configured system. The service provider device 12 is a terminal managed by a service provider (SP) that provides such an electronic commerce service, and issues an electronic value provided for the service via the Internet 14. In addition, the service provider device 12 also has a function as an electronic certificate authority that guarantees the validity of the electronic value.
[0011]
The mobile communication terminal 20 is, for example, a terminal such as a mobile phone or a PDA, and has an information communication function. The portable communication terminal 20 is provided with a tamper-resistant UIM (tamper-resistant memory) 28 and a general-purpose memory 30. Since the UIM (for example, an IC chip) 28 includes a storage unit and an arithmetic circuit (not shown), various controls such as transmission / reception and storage of information can be performed. The general-purpose memory 30 includes, for example, a compact flash (registered trademark) memory and a smart media (registered trademark), and these memories are suitable as memories of the mobile communication terminal 20 in terms of size and data capacity. . In the present specification, “having tamper resistance” means having an ability to block access (illegal access) from anyone other than an authorized person.
[0012]
The mobile communication terminal 20 mainly includes, as physical components, an information processing device such as a CPU, a storage device such as a memory, an audio processing device, a transmission / reception device, and the like. The mobile communication terminal 20 mainly includes a network communication unit 21, a local communication unit 22, a control unit 24, and a built-in memory 26 as functional components.
[0013]
The network communication unit 21 wirelessly connects to the Internet 14, and the local communication unit 22 performs wired, wireless, or non-contact data communication with the gate device 40. The control unit 24 performs a predetermined process on data received from each of the communication units 21 and 22 and data stored in various memories 26, 28 and 30 of the mobile communication terminal 20. The built-in memory 26 is a memory that temporarily stores data mainly when data is exchanged between the control unit 24 and the UIM 28 and the general-purpose memory 30.
[0014]
The gate device 40 mainly includes, as physical components, an information processing device such as a CPU, a storage device such as a memory, a transmission / reception device, a gate, and the like. The gate device 40 mainly includes a network communication unit 41, a local communication unit 42, a control unit 44, and a memory 46 as functional components. The network communication unit 41 performs a wired or wireless connection to the Internet 14, and the local communication unit 42 performs a wired, wireless or non-contact data communication with the portable communication terminal 20. The memory 46 is a memory for storing various data necessary for performing communication with the mobile communication terminal 20, and this memory also has tamper resistance. Further, the control unit 44 performs a predetermined process on data received from each of the communication units 41 and 42 and data stored in the memory 46.
[0015]
The UIM 28 attached to the mobile communication terminal 20 stores a user private key, a PKI engine, and a user public key certificate in advance when performing communication with the gate device 40. This “user secret key” is a user-specific secret key corresponding to the public key cryptosystem. The “PKI engine” is a program (algorithm) corresponding to the public key cryptosystem, and more specifically, a program (encryption program) for attaching an electronic signature to certain information using a user's secret key. And functions as a program for decrypting data encrypted with the user public key corresponding to the user secret key using the user secret key. Further, "user's public key certificate" is certificate data issued by a service provider as an electronic certificate authority and guaranteeing the validity of a user public key corresponding to a user private key. This certificate data is created by adding a digital signature to the user public key and its attribute information (owner name, validity period, etc.) using a private key (SP private key) unique to the service provider. Therefore, the validity of the "user's public key certificate" can be confirmed by anyone who has the SP public key corresponding to the SP private key. Usually, the user registers the user private key with the service provider via the Internet 14 and obtains the user's public key certificate from the service provider device 12.
[0016]
The general-purpose memory 30 attached to the mobile communication terminal 20 stores an electronic ticket to which a service provider's electronic signature (SP electronic signature) is attached. This electronic ticket is electronic value information provided by the service provider. The user can pass through the gate without preparing cash or a ticket by purchasing such information in advance and storing it in his or her mobile communication terminal 20 via the Internet 14 or the like. Similarly to the user's public key certificate, the SP electronic signature attached to the electronic ticket can be verified for validity using the SP public key.
[0017]
The memory 46 of the gate device 40 stores a public key certificate of a service provider and a PKI engine in advance when performing communication with the mobile communication terminal 20. Methods for storing such information include, for example, a method of storing the information at the time of shipment of the device, a method of connecting to the Internet 14 and obtaining the information from the service provider device 12, and the like. The “public key certificate of the service provider” is certificate data issued by the service provider described above, which guarantees the validity of the SP public key corresponding to the SP private key. This certificate data is created by adding an electronic signature to the SP public key and its attribute information using the SP private key. Therefore, the validity of the "service provider's public key certificate" can be confirmed by anyone who has the SP public key corresponding to the SP private key.
[0018]
Next, a procedure in which the user opens the gate of the gate device 40 using the mobile communication terminal 20 will be described.
[0019]
As shown in FIG. 2, first, when a release request is transmitted from the mobile communication terminal 20 to the gate device 40 by a user operation (S10), the gate device 40 receives the release request (S12). When the gate device 40 receives the release request and is ready to open, the gate device 40 transmits a ready signal indicating that to the portable communication terminal 20 that has issued the release request from the local communication unit 42 (S14). When the portable communication terminal 20 receives the ready signal by the local communication unit 22 (S16), the control unit 24 transmits the ready signal to the electronic ticket to which the SP electronic signature is attached using the user secret key stored in the UIM 28 and the PKI engine. An electronic signature (user electronic signature) is created, and the user electronic signature is further attached to the electronic ticket (S18). In other words, two electronic signatures, an SP electronic signature and a user electronic signature, are attached to the electronic ticket.
[0020]
Then, the local communication unit 22 of the mobile communication terminal 20 transmits the electronic ticket with the two electronic signatures and the user's public key certificate to the gate device 40 (S20). When the local communication unit 42 of the gate device 40 receives the information (S22), the control unit 44 converts the public key certificate of the user received by the local communication unit 42 into the public key certificate of the SP stored in the memory 46. Verification is performed using the SP public key included in the certificate (S24). When the validity of the user's public key is recognized (the verification is successful), the control unit 44 then includes the user's public key and the user's public key certificate received from the mobile communication terminal 20 in the public key certificate. The two electronic signatures attached to the electronic ticket are verified with the user public key to be used (S26). If the two electronic signatures are successfully verified, the control unit 44 of the gate device 40 further determines whether the content of the electronic ticket is valid (expiration date, etc.) (S28). If confirmed, the gate is opened (S30). If the verification of the user's public key certificate fails, if the verification of the two digital signatures fails, or if the validity of the ticket cannot be confirmed, the control unit 44 notifies the user of an error and performs processing. Stop the flow. In such a case, the electronic ticket received by the gate device 40 may be returned to the mobile communication terminal 20 before the processing flow is stopped. The verification of the two electronic signatures can be omitted as appropriate in consideration of the security level and the processing time.
[0021]
As described in detail above, in the communication system 10, data including an electronic ticket is transmitted from the portable communication terminal 20 to the gate device 40, and if the electronic ticket is valid, the gate device 40 Opens. In this series of gate open processing flows, the user secret key and the PKI engine are stored in the UIM 28 of the mobile communication terminal 20. As described above, by storing the user secret key and the PKI engine that require high confidentiality in the tamper-resistant UIM 28, the confidentiality of these data can be sufficiently ensured. As a result, compared with the case where the user secret key and the PKI engine are stored in the built-in memory 26 and the general-purpose memory 30 in which the tamper resistance is not taken into account, the transfer of the electronic ticket can be performed safely. Along with this, a special effect that electronic values such as electronic tickets downloaded from the network can be used more safely can be obtained. Note that the electronic value in the first embodiment is not limited to an electronic ticket, and may be, for example, an electronic membership card, an electronic employee card, or an electronic coupon. Further, the data communication between the gate device 40 and the service provider 12 may use a dedicated line (broken arrow in FIG. 1) without passing through the Internet 14 for improving security.
[0022]
Next, a second embodiment of the portable communication terminal according to the present invention will be described. Note that the same or equivalent elements as those of the first embodiment will not be described repeatedly.
[0023]
As shown in FIG. 3, a communication system 50 according to the second embodiment includes a service provider device 52, a mobile communication terminal 60, and a POS cash register (recipient terminal) 70. The service provider device 52 is connected to the Internet 14, and the portable communication terminal 60 and the POS register 70 are also connectable to the Internet 14. The portable communication terminal 60 and the POS register 70 communicate with each other by wire or wireless communication. The communication system 50 is a system mainly configured to use the electronic value (for example, electronic money) stored in the mobile communication terminal 60 by the user of the mobile communication terminal 60 for settlement at the POS register 70. is there. The service provider device 52 is a terminal managed by a service provider that provides such an electronic commerce service, and issues an electronic value provided for this service via the Internet 14. Further, the service provider device 52 has a function as an electronic certificate authority that guarantees the validity of the electronic value.
[0024]
The portable communication terminal 60 differs from the first embodiment only in that the general-purpose memory 30 attached to the portable communication terminal 20 is not attached. The UIM 28 of the mobile communication terminal 60 stores a user private key, a PKI engine, electronic money with an electronic signature, a public key certificate of the user, a public key certificate of the SP, and history information. The electronic signature attached to the electronic money is an electronic signature created by a user who intends to use the POS cash register 70 using a secret key unique to “a POS cash register (not shown) used last time”. If there is no “POS register used last time”, that is, if the electronic money stored in the UIM 28 has never been used, an electronic signature (SP electronic signature) by the service provider is attached to the electronic money. ing. The “history information” is a public key certificate of the “POS register used last time” and has the SP electronic signature described above.
[0025]
The network communication unit 21 of the portable communication terminal 60 wirelessly connects to the Internet 14, and the local communication unit 22 performs wired, wireless, or non-contact data communication with the POS register 70. Further, the control unit 24 of the mobile communication terminal 60 performs a predetermined process on data received from each of the communication units 21 and 22 and data stored in various memories 26 and 28 of the mobile communication terminal 60. The built-in memory 26 is a memory that temporarily stores data mainly when data is exchanged between the control unit 24 and the UIM 28.
[0026]
The POS register 70 mainly includes, as physical components, an information processing device such as a CPU, a storage device such as a memory, a transmission / reception device, and the like. The POS register 70 mainly includes a network communication unit 71, a local communication unit 72, a control unit 74, and a memory 76 as functional components.
[0027]
The network communication unit 71 makes a wired or wireless connection to the Internet 14, and the local communication unit 72 makes a wired, wireless or non-contact data communication with the portable communication terminal 60. The memory 76 is a memory for storing various data necessary for performing communication with the mobile communication terminal 60. The control unit 74 performs a predetermined process on data received from each of the communication units 71 and 72 and data stored in the memory 76.
[0028]
In the memory of the POS register 70, a POS secret key, a POS public key certificate, an SP public key certificate, a PKI engine, and an addition / subtraction program are stored in advance when communicating with the mobile communication terminal 60. The “POS secret key” is a secret key unique to the POS register 70. The “POS public key certificate” is certificate data issued by the service provider for guaranteeing the validity of the POS public key corresponding to the POS private key. This certificate data is created by adding an electronic signature to the POS public key and its attribute information using a private key unique to the service provider. Therefore, the validity of this "POS public key certificate" can be confirmed by anyone who has the SP public key corresponding to the SP private key. The “addition / subtraction program” is a program for reducing (in some cases increasing) the value of electronic money received by the POS register 70 from the mobile communication terminal 60 in accordance with the amount of a product or service.
[0029]
Next, a procedure in which the user exchanges electronic money with the POS register 70 using the portable communication terminal 60 will be described.
[0030]
As shown in FIG. 4, first, when an electronic money use request is transmitted from the portable communication terminal 60 to the POS register 70 by a user operation (S40), the POS register 70 receives the use request (S42). The POS register 70 that has received the use request transmits a ready signal from the local communication unit 72 to the portable communication terminal 60 that has issued the use request when the preparation for accepting the use of electronic money is completed (S44). When the portable communication terminal 60 receives the ready signal by the local communication unit 22 (S16), the control unit 24 further uses the user secret key stored in the UIM 28 and the PKI engine to add the electronic signature to the electronic money. An electronic signature is attached (S48). That is, the electronic money has two electronic signatures, an electronic signature using the SP private key and an electronic signature using the user private key.
[0031]
Then, the local communication unit 22 of the mobile communication terminal 60 transmits the electronic money with the two electronic signatures, the public key certificate of the user, and the history information to the POS register 70 (S50). When the local communication unit 72 of the POS register 70 receives the information (S52), the control unit 74 stores the public key certificate and the history information of the user received by the local communication unit 72 in the SP of the SP stored in the memory 46. Verification is performed using the SP public key included in the public key certificate (S54). As described above, since the public key certificate and the history information of the user are public key certificates that are electronically signed with the SP private key, such verification can be performed because they are SP public key certificates.
[0032]
Then, if the validity of the user's public key certificate and history information is recognized (successful verification), the control unit 44 then proceeds to the previously used POS register included in the user's public key and history information. The two electronic signatures attached to the electronic money are verified with the public key (S56). When the two electronic signatures are successfully verified, the control unit 74 of the POS register 70 performs an addition / subtraction process (for example, decreases the value by a predetermined value) of the electronic money by the addition / subtraction program stored in the memory 76 (S58). If the verification of the user's public key certificate and history information has failed, and if the verification of the two electronic signatures has failed, the control unit 74 notifies the user of an error and stops the processing flow. The verification of the two electronic signatures can be omitted as appropriate in consideration of the security level and the processing time.
[0033]
The electronic money that has been subjected to the addition and subtraction processing by the control unit 74 of the POS register 70 is further signed by the control unit 74 with the POS secret key (S60). Then, the POS cash register 70 transmits the electronic money and the POS public key certificate signed with the POS secret key from the local communication unit 72 to the portable communication terminal 60 (S62).
[0034]
When the mobile communication terminal 60 receives the public key certificate of the electronic money and the POS to which the signature has been added by the local communication unit 22 (S64), the control unit 24 verifies the public key certificate with the SP public key (S64). S66). When the verification of the public key certificate is successful, the signature of the POS register 70 attached to the electronic money is verified using the POS public key included in the public key certificate (S68). If the signature verification is successful, the local communication unit 22 of the mobile communication terminal 60 sends a confirmation signal to the POS register 70 to notify the POS register 70 that the electronic money subjected to the addition / subtraction processing by the POS register 70 has been received. 70. Further, the control unit 24 overwrites and updates the information of the electronic money with the signature on the original electronic money information in the UIM 28 with the electronic signature of the POS cash register used last time, and updates the POS cash register 70. Is stored in the UIM 28. The confirmation signal includes, for example, user identification information, an increase / decrease amount of electronic money, date and time, and the like. Then, the POS register 70 receives the confirmation signal by the local communication unit 72 and stores it in the memory 76 (S72). The confirmation information stored in the memory 76 in this manner is, for example, periodically sent to the service provider device 52, and the service provider manages the transfer of electronic money between the portable communication terminal 60 and the POS register 70. .
[0035]
As described in detail above, in the communication system 50, data including electronic money is transmitted from the portable communication terminal 60 to the POS register 70, and if the electronic money is appropriate, the POS register 70 The value of the electronic money is added and subtracted and returned to the mobile communication terminal 60. In this electronic money transfer processing flow, the user secret key and the PKI engine are stored in the UIM 28 of the mobile communication terminal 60. As described above, by storing the user secret key and the PKI engine that require high confidentiality in the tamper-resistant UIM 28, the confidentiality of these data can be sufficiently ensured. As a result, compared with the case where the user secret key and the PKI engine are stored in the built-in memory 26 in which the tamper resistance is not considered, the transfer of the electronic money can be performed safely. The electronic value in the second embodiment is not limited to electronic money, and may be, for example, an electronic point or a coupon type electronic ticket.
[0036]
In addition, when the memory capacity of the UIM 28 is sufficiently large, only the UIM 28 may be attached to the two portable communication terminals 20 and 60 in addition to the built-in memory 26, and the memory capacity of the UIM 28 is insufficient. In this case, a general-purpose memory 30 may be further attached.
[0037]
【The invention's effect】
According to the present invention, there is provided a mobile communication terminal and an information transmitting / receiving method in which the security of electronic value transfer is improved.
[Brief description of the drawings]
FIG. 1 is a system configuration diagram showing a communication system according to a first embodiment of the present invention.
FIG. 2 is a flowchart showing a procedure in which a user opens a gate of a gate device using a portable communication terminal.
FIG. 3 is a system configuration diagram showing a communication system according to a second embodiment of the present invention.
FIG. 4 is a flowchart showing a procedure in which a user exchanges electronic money with a POS register using a portable communication terminal.
[Explanation of symbols]
10, 50 communication system, 20, 60 mobile communication terminal, 28 UIM, 40 gate device, 70 POS cash register.

Claims (2)

Equipped with tamper-resistant memory having tamper resistance,
An electronic signature is attached to the electronic value using the user's secret key, the electronic value with the electronic signature is transmitted to the destination terminal, and processing corresponding to the electronic value is performed on the destination terminal. Mobile communication terminal,
A portable communication terminal, wherein the tamper-resistant memory stores a secret key of the user and an encryption program for creating an electronic signature using the secret key of the user. A tamper-resistant memory having tamper resistance is provided, an electronic signature is attached to an electronic value using a user's secret key, and the electronic value with the electronic signature is transmitted to a destination terminal to transmit the electronic value. An information transmitting and receiving method using a mobile communication terminal that causes a destination terminal to perform a process according to
An information transmission / reception method, wherein a secret key of the user and an encryption program for creating an electronic signature using the secret key of the user are stored in the tamper-resistant memory of the portable communication terminal.

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