KR100722663B1 - Method of protecting the certificate of lost mobile terminal using DARC - Google Patents

Abstract

The present invention relates to a method for protecting a certificate stored in a lost mobile communication terminal, and transmits terminal information and DRM information corresponding to a data radio channel (DARC) according to a subscriber's certificate lock service request. It provides a method of protecting a certificate of a lost mobile terminal by using a data radio channel to change the DRM information of the certificate with the DRM information received from the mobile communication terminal to DARC to restrict the use of the certificate by unauthorized users. There is an effect that prevents the user from using the certificate stored in the mobile terminal that someone else has lost, and even if the legitimate user loses the mobile terminal, there is no effect to reissue the certificate.

Data Radio Channel (DARC), Lost Mobile Device, Certificate Protection, Digital Rights Management (DRM)

Description

{Method of protecting the certificate of lost mobile terminal using DARC}

1 is a configuration diagram of an embodiment of a communication network to which the present invention is applied.

2 is a flowchart illustrating a method of protecting a certificate of a lost mobile communication terminal using a data radio channel according to the present invention.

* Explanation of symbols on the main parts of the drawing

10: mobile communication terminal 30: terminal loss processing server

40: radio broadcasting center 50: radio broadcasting transmitter

The present invention relates to a method for protecting a certificate stored in a lost mobile communication terminal, and more particularly, to transmit terminal information and DRM information corresponding to a data radio channel (DARC) according to a certificate lock service request of a subscriber. A method of protecting a certificate of a lost mobile terminal by using a data radio channel to change the DRM information of the certificate with the DRM information received by the DARC from the lost mobile terminal to restrict use of the certificate by a fraudulent user. It is about.

In the present invention, a lost mobile communication terminal refers to a mobile communication terminal lost by a subscriber, and a certificate of a lost mobile communication terminal is a certificate stored in the lost mobile communication terminal. The subscriber provides an Internet banking service and a shopping mall service. It is used as information for personal identification when receiving.

Meanwhile, in the present invention, digital rights management (DRM) refers to a user who normally purchases (issued) a variety of content (certificate of the present invention) such as video, audio, and program. This means that it can be used for a certain number of times. In the present invention, such DRM information refers to the time information or the number of readings used as the certificate usage restriction parameter, and the time information refers to the time when the certificate is available [that is, the DRM validity period (start time, expiration time, where time is “year / month / Days / hours / minutes / seconds]), and the number of reads means the number of times that a certificate can be used (that is, the number of remaining DRM usages).

Recently, with the activation of electronic commerce (eg, internet banking, purchase of goods, etc.) through the wireless Internet, wireless public key infrastructure technology has been in the spotlight. In general, a public key authentication technology (also known as a public key cryptography method) is a method of performing encryption / decryption using a public key and a private key forming a key pair.

In public key authentication technology, it is necessary to prove that the owner of the public key is a legitimate user and that the user owns the private key corresponding to the public key. The user is authenticated by a certification authority (CA). In other words, the certification authority issues a certificate for the public key to the user and authenticates that the user is a legitimate user. The certificate contains the receipt number, signature algorithm, issuer, public key algorithm, public key, and the like.

On the other hand, people receive a certificate from an accredited certification center through a computer installed at home, for example, to receive Internet banking service anytime and anywhere through a computer installed at home or at work, or a laptop or mobile terminal or PDA owned by a company. After receiving the certificate, copy this certificate and save it to USB memory, floppy disk, computer, notebook, mobile terminal, PDA, etc.

By the way, when all the certificates are stored in the computer, laptop, mobile terminal, PDA as described above, there is a convenience that people can be provided anytime / anywhere Internet banking service, but a device having a portable characteristics, for example, a mobile terminal In the event of a loss, people are reluctant to expose their certificates to others and request that the certificate be revoked through a computer to an authorized certification center. Thus, the accredited certification center will revoke the subscriber's certificate, which is a hassle to reissue all the certificates stored in the computer, notebook, PDA as above.

As such, when a mobile communication terminal is lost, people must be reissued a certificate from an authorized certification center through a computer, and then copy the reissued certificate and store it again in a USB memory, a floppy disk, a computer, a notebook, a PDA, and the like. In addition, if a person who has lost a mobile communication terminal does not request revocation of his or her certificate, an unauthorized user who has acquired the terminal acquires a password entered in the certificate through a cracking program or a terminal replication, and then moves another person. The communication terminal can be connected to the Internet shopping mall to purchase goods.

On the other hand, the lost mode is mounted in the mobile communication terminal. For example, when a user loses his or her mobile terminal, if the user calls the customer center using a landline phone or accesses the web page of the terminal loss processing server associated with the customer center using a computer, the mobile terminal is reported as lost. The mobile operator transmits a lost mode command to the corresponding mobile communication terminal. Accordingly, the lost mobile communication terminal of the subscriber sets a lost mode in response to receiving a lost mode command so that an unauthorized user who acquires the lost mobile communication terminal cannot use a mobile communication service such as making a call.

However, in the prior art as described above, although it is possible to prevent a fraudulent user from making a phone call or using a wireless Internet service for a lost mobile communication terminal, for example, since the mobile communication service is limited, the illegal user cannot use the wireless Internet service. The use of certificates is blocked, but it does not prevent unauthorized users from copying other people's certificates stored on the mobile terminal to a computer through a USB cable and using them on the computer.

The present invention has been proposed to solve the above problems and to meet the above requirements, and transmits terminal information and DRM information corresponding to the data radio channel (DARC) according to the subscriber's certificate lock service request, and thus is lost. It provides a method of protecting a certificate of a lost mobile terminal by using a data radio channel to change the DRM information of the certificate with the DRM information received by DARC in the mobile communication terminal to restrict the use of the certificate by unauthorized users. There is a purpose.

In the method of the terminal loss processing server of the present invention for achieving the above object, in the method for protecting the certificate of the mobile communication terminal in the terminal loss processing server, receiving the DRM information from the subscriber who lost the mobile communication terminal certificate A first step of receiving a locking service; A second step of identifying terminal information of the subscriber with reference to the subscriber's receipt, and binding the terminal information and the received DRM information to generate an encrypted certificate lock command; And a third step of forwarding and transmitting the generated certificate lock command to the radio broadcasting center.

Meanwhile, in the method of the mobile communication terminal of the present invention, in the method of protecting a certificate in the mobile communication terminal, while waiting for data reception through a radio network, a certificate lock command is received through a data radio channel (DARC). First step; Extracting the DRM information by decrypting the received certificate lock command; And a third step of changing DRM information of a certificate previously stored as the extracted DRM information.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description of the present invention, detailed descriptions of well-known functions or configurations will be omitted if it is determined that the detailed description of the present invention may unnecessarily obscure the subject matter of the present invention. Terms to be described later are terms defined in consideration of functions in the present invention, and may be changed according to intentions or customs of users or operators. Therefore, the definition should be made based on the contents throughout the specification.

1 is a configuration diagram of an embodiment of a communication network to which the present invention is applied.

As shown in FIG. 1, a communication network to which the present invention is applied includes a mobile communication terminal 10, a base station 20, a terminal loss processing server 30 linked to a mobile communication customer center, a radio broadcasting center 40, and a radio. A broadcast transmitter 50 is included. In addition, although not shown in the drawings, the mobile communication network further includes a mobile communication system accommodating the base station 20 such as a base station controller, a mobile communication switching center, a home location register, a packet data serving node, an SMS center, and the like. It is provided.

The mobile terminal 10 is a terminal lost by the subscriber, and the subscriber calls the mobile communication customer center with a landline telephone 11 installed in the home, etc., and reports his or her mobile terminal loss through ARS or an agent's response. Or by accessing the webpage of the terminal loss processing server 30 with a computer 12 installed in a company or the like to report the loss of its own mobile communication terminal.

In the present invention, the terminal loss processing server 30 connected to the mobile communication customer center receives the certificate lock service from the subscriber of the mobile terminal 10 lost, receives the DRM information that is certificate use restriction information from the subscriber, Check the terminal information of the mobile communication terminal 10 and encrypt the terminal information and the above DRM information to generate a certificate lock command and transmit the certificate lock command to the outside through a data radio channel (DARC, hereinafter referred to as "DARC"). do. Specific information for encrypting the terminal information and the DRM information is implemented based on a public key authentication technology that performs encryption and decryption by pairing with a public key and a private key, and through a public key corresponding to a subscriber who has subscribed to a certificate lock service. It is preferable to encrypt the terminal information and the DRM information.
In addition, the DRM information, which is certificate use restriction information issued from the terminal loss processing server 30, is issued from a certification authority such as an accredited authentication center, and changes the DRM information of a certificate that is previously stored in the mobile communication terminal 10 to an illegal user. This is to prevent illegal use of certificates.
In addition, the present invention maintains the terminal loss service as it is, that is, when receiving a mobile communication terminal loss report from the subscriber prohibits the transmission of the corresponding mobile communication terminal 10 to the mobile communication service, especially fraudulent by fraudulent users The user is connected to the wireless Internet shopping mall by the mobile communication terminal 10 to prevent the purchase of goods with another person's certificate.

In particular, although the certificate lock command may be transmitted to the mobile communication terminal 10 as an incoming call through the existing mobile communication network, in this case, although the unauthorized user presses a call button of the mobile communication terminal 10 to receive a call, the mobile communication terminal ( 10) The certificate lock command can be received. Therefore, in order to forcibly send a certificate lock command to the mobile communication terminal 10 without manipulating a mobile communication terminal by a fraudulent user, it is preferable to transmit the DARC to the mobile communication terminal 10, and the DARC function is always performed in the mobile communication terminal 10 at all times. Do. The mobile communication terminal 10 will be described later in association with related elements.

On the other hand, there are various types of certificates, such as general-purpose electronic certificates used in banks and financial settlement service providers such as Internet banking, bank insurance certificates used in banking, insurance and e-government complaint services, and corporate banking for corporate customers. Certificates, certificates for credit cards used in credit card business. In the present invention, a plurality of certificates may be stored in the mobile communication terminal 10 according to the use purpose of the subscriber.
Such a certificate may be stored in the mobile communication terminal 10, and when the mobile communication terminal 10 storing the certificate is lost, the certificate previously stored in the mobile communication terminal 10 by the unauthorized user acquired by the mobile communication. Whether the terminal 10 itself or a certificate is transferred to a computer, it may be illegally used. In order to prevent this, the DRM of a certificate previously stored in the terminal is transmitted as the certificate lock command is transmitted from the terminal loss processing server 30 to the mobile terminal 10 by a certificate lock execution request of the subscriber who lost the terminal. Change the information to restrict unauthorized users from using certificates. A detailed process thereof will be described later.

In addition, the certificate lock command of the terminal loss processing server 30 is formatted by the radio broadcasting center 40 in a format suitable for DARC so that the certificate lock command generated by the terminal loss processing server 30 can be transmitted through the DARC (hereinafter, referred to as a certificate lock command). &Quot; certificate lock command for DARC "

The radio broadcast center 40 transmits a known radio music broadcast and, in accordance with a known DARC transmission protocol, various information (eg, news, stock, weather, Traffic information, etc.) and transmits it through a pre-established radio broadcasting network (radio broadcasting transmitting station 50).

In this case, when the subscriber's certificate lock command is transmitted through a data radio channel having airwave characteristics, the terminal information is included in the certificate lock command so that the lost mobile communication terminal 10 processes the certificate lock command. The mobile communication terminal 10 recognizes and processes the certificate lock command sent to the user through the terminal information, and the mobile communication terminal 10 does not process the received certificate lock command even if the mobile terminal is lost. .

In addition, considering that the personal information of the subscriber is inserted into the certificate lock command, the mobile terminal 10 is implemented such that the certificate lock command sent through the DARC is decrypted through the private key specific to the subscriber. Only the mobile communication terminal 10 can decrypt the certificate lock command.

Meanwhile, the lost mobile communication terminal 10 is equipped with a program for protecting a certificate of the present invention so that a certificate lock command transmitted through DARC can be received / processed by the mobile communication terminal 10. Such a program is illegal. It is desirable that the security processing is performed so that it is not tampered, manipulated, or modified by the user's access.

In particular, the mobile communication terminal 10 is equipped with a radio broadcast receiving function, in particular, DARC receiving function, such DARC receiving function and certificate protection program is always driven (executed) on the lost mobile communication terminal 10 to power the terminal It is desirable to always keep the process until it is off. In detail, the mobile communication terminal 10 receives data through DARC with a DARC receiving module such as an FM antenna (DARC antenna), an FM tuner, an FM demodulator, a DARC demodulator (LMSK demodulator), a DARC decoder, and the like.

When receiving the certificate lock command from the lost mobile communication terminal 10 through the DARC as described above to change the DRM information of the certificate stored in the terminal with the DRM information extracted through the decryption process, such that the lost mobile communication terminal 10 Use of the certificate of the mobile communication terminal 10 is restricted by the obtained unauthorized user. In addition, the DRM information on the mobile communication terminal 10 may be recorded in a header area of a file constituting the certificate or the like, or matched with the certificate information in a separate table other than the file constituting the certificate. Hereinafter, the present invention will be described in more detail with reference to FIG. 2.

2 is a flow chart of an embodiment of a method for protecting a certificate of a lost mobile communication terminal using a data radio channel according to the present invention. Hereinafter, a subscriber loses the mobile communication terminal 10 to the computer 12. An example of reporting a loss of the mobile communication terminal by accessing a web page of the loss processing server 30 will be described.

First, the subscriber loses the mobile communication terminal 10 and accesses the webpage of the terminal loss processing server 30 with the computer 12, and reports the loss of the mobile communication terminal and checks an item on the webpage, that is, a certificate lock service item. DRM information for restricting use of this certificate [Example; Set the validity period of the DRM to the current time (or "+0") to expire, or set the remaining number of DRM to "+0" to expire] to receive the certificate lock service (200). Here, the certificate lock service of the present invention is a service for protecting the certificate of the lost mobile communication terminal from others as an option of the terminal loss service.
Furthermore, the DRM information, which is included in the certificate lock command and transmitted from the terminal loss processing server 30 to the mobile communication terminal 10, is basic data for changing the DRM information of the certificate previously stored in the mobile communication terminal 10. As utilized, it is used to prevent fraudulent users, i.e., others, from using the certificate.

In particular, as described above, the mobile communication terminal 10 may store various certificates according to the use purpose of the subscriber, and the subscriber may not properly recognize the type of certificate stored by the subscriber or may restrict the use of the certificate. Most people don't recognize information about this. Therefore, it is practically difficult for subscribers to individually designate a certificate and input each DRM information. Thus, even if the subscriber inputs one DRM information, the DRM information is stored in all certificates stored in the mobile communication terminal 10. It is preferable to apply in common.

As another example, a subscriber calls a mobile communication customer center using a wired telephone 11 or the like after losing a mobile communication terminal 10 and reports a loss of a mobile communication terminal according to an ARS announcement. It is also possible to input the DRM information of the certificate, preferably the information that expires the DRM time or expires the number of DRM usage by pressing the button of (11).

As another example, the subscriber loses the mobile communication terminal 10, calls the mobile communication customer center with a wired telephone 11, etc., and reports the loss of the mobile communication terminal through the counseling of the counselor. The DRM information, preferably, may reply to expire the DRM time or expire the number of DRM usage.

Then, the terminal loss processing server 30 receives the subscriber's certificate lock service and checks the subscriber's input DRM information, and inquires the terminal profile of the lost mobile communication terminal 10 of the subscriber. Check (201). Here, as the terminal information, an eletronic serial number (ESN), a mobile identification number (MIN), an international mobile subscriber identity (IMSI), etc.] are used, and the terminal information is information uniquely representing the lost mobile communication terminal 10. Anything is good.

Thereafter, the terminal loss processing server 30 binds the checked terminal information and DRM information, encrypts the bound information, and generates a certificate lock command (202). Here, the terminal information constituting the certificate lock command in the process of encrypting the certificate lock command is used as a parameter through a security algorithm such as a hash algorithm is converted into a specific output value. In addition, the DRM information constituting the certificate lock command is encrypted through the public key corresponding to the subscriber based on the common public key authentication technology.
The certificate lock command including the encrypted terminal information and the DRM information is transmitted to the mobile communication terminal 10, and the mobile communication terminal 10 stores a specific output value of the terminal information encrypted by the hash algorithm in the certificate. Compares the hash value included in the subscriber to determine whether the subscriber is matched, decrypts the encrypted DRM information based on the decryption algorithm provided in the subscriber's specific private key for changing the DRM information of the certificate that is already stored It is desirable to use as basic data.

Then, the terminal loss processing server 30 transfers (forwards) the generated certificate lock command to the radio broadcasting center 40 and instructs the transmission of the certificate lock command (203).

Accordingly, the radio broadcast center 40 converts the certificate lock command into a certificate lock command for DARC (204). At this time, the radio broadcasting center 40 inserts the certificate lock command into the data area of the frame according to the data radio channel (DARC) transmission protocol and converts the certificate lock command into a certificate lock command for DARC. That is, the certificate lock command generated by the terminal loss processing server 30 is packet data. Since the packet data is not directly transmitted by airwaves, the certificate lock command is preferably converted into DARC data suitable for airwaves.

Then, the radio broadcast center 40 transmits the DARC certificate lock command to the outside, that is, the mobile communication terminal 10 via the radio broadcast transmitting station 50 (205). At this time, the radio broadcasting center 40 encodes the DARC certificate lock command into an analog signal in the FM frequency band according to a known data radio channel (DARC) transmission protocol, and the DARC certificate lock command in the form of the encoded analog signal is encoded. After FM high frequency conversion, FM modulation is performed to carry a DARC certificate lock command in a spare band (unallocated band) of the FM frequency bands to be transmitted through the radio broadcasting transmitter 50.

In addition, the FM frequency band (data radio channel) for issuing a certificate lock command for DARC is preferably allocated from the radio control station, and the FM is allocated to another operator for other purposes (eg, traffic broadcasting, stock information provision, etc.). It is preferable that the band does not collide with the frequency band. On the other hand, the DARC certificate lock command carried on the FM frequency band is preferably added to the Cyclic Redundancy Check (CRC) region for data transmission error check.

Accordingly, the mobile communication terminal 10 forcibly receives the DARC certificate lock command through the DARC while the DARC receiving function and the certificate protection program are always executed (206). Here, the mobile communication terminal 10 is preferably notified of the FM frequency band, that is, the FM frequency band for receiving the certificate lock command for DARC from the terminal loss processing server 30 or the radio broadcasting center 40 side in advance. In addition, it is preferable that the channel of the pre-installed FM tuner is fixedly set to the DARC certificate lock command reception channel and waits for the DARC certificate lock command to be forcibly received.

Then, the mobile communication terminal 10 compares a specific output value of the terminal information of the certificate lock command formed through the hash algorithm with a hash value included in the certificate previously stored in the terminal, and determines whether the subscriber is matched, and locks the certificate. The DRM information of the command is decoded to extract the corresponding DRM information (207).

On the other hand, if the mobile terminal 10 is unable to decrypt the certificate lock command with the terminal information of its own (mobile communication terminal) as a parameter, the certificate lock command is regarded as data for another mobile communication terminal and discarded. desirable. In addition, it is preferable that the mobile communication terminal 10 restores the DARC certificate lock command to the certificate lock command by performing a known DARC decoding process before performing the certificate lock command decryption.

Then, the mobile communication terminal 10 extracts the extracted DRM information [Yes; The DRM validity period is set to the current time (or "+0") or the remaining number of DRM usage is set to "+0"] to change the DRM information of all certificates previously stored in the memory or the like (208). In addition, the DRM information on the mobile communication terminal 10 may be recorded in a header area of a file constituting the certificate or the like, or matched with the certificate information in a separate table other than the file constituting the certificate.

Accordingly, the DRM information of all certificates stored in the mobile communication terminal 10 is changed to restrict use of the certificate by the unauthorized user. In particular, the illegal user connects the mobile communication terminal 10 and the computer with a USB cable. Even if the certificate is copied to the computer, the time information and the DRM remaining number of parameters that constitute the DRM information of the certificate on the computer are changed to be disabled so that the certificate on the computer is a function of the certificate for proving that the certificate on the computer is a real user. Will be lost. On the other hand, the right subscriber is a certificate stored in the computer due to the service of the present invention forcibly changing the DRM information of the certificate on the mobile terminal even if the mobile terminal is lost (this certificate is different from the certificate stored in the mobile terminal) Internet banking services can be used without destroying them. Furthermore, when a lost mobile terminal is returned from another person, the subscriber can contact the customer center and change the DRM information of the certificate stored in the mobile terminal (to allow unlimited use such as "+1,000,000"). The certificate can be used through the mobile communication terminal.

While the content of the present invention has been described by way of examples, the embodiments of the present invention are merely illustrative of the present invention and should not be construed as limiting the scope of the present invention. Those skilled in the art to which the present invention pertains may modify or alter the present invention in various forms within the principles and scope described in the claims herein.

The present invention as described above has the effect of preventing unauthorized users from unauthorized use of the certificate stored in the mobile communication terminal lost by another person, and even if the legitimate user loses the mobile communication terminal, there is an effect that does not need to be issued a certificate again. .

Claims (11)

In the terminal loss processing server to protect the certificate of the mobile communication terminal, A first step of receiving a certificate lock service by receiving DRM information from a subscriber who has lost a mobile communication terminal; A second step of identifying terminal information of the subscriber with reference to the subscriber's receipt, and binding the terminal information and the received DRM information to generate an encrypted certificate lock command; And A third step of forwarding and transmitting the generated certificate lock command to the radio broadcasting center; How to protect the certificate of the lost mobile communication terminal using a data radio channel comprising a. The method of claim 1, The radio broadcasting center, when receiving a certificate lock command transmission instruction from the terminal loss processing server, converts the certificate lock command into a certificate lock command of a format suitable for a data radio channel (DARC) and transmits it to the outside through a radio network. A method of protecting a lost mobile device's certificate using a data radio channel. The method of claim 2, The DRM information is a method of protecting a certificate of a lost mobile communication terminal using a data radio channel, characterized in that it comprises a DRM validity period or the remaining number of DRM usage limit parameters of the certificate. The method of claim 2, The terminal information may include an eletronic serial number (ESN) or a mobile identification number (MIN) or an international mobile subscriber identity (IMSI). The method according to any one of claims 1 to 4, In the second step, the certificate lock command encryption process is a method of protecting a certificate of a lost mobile communication terminal using a data radio channel, characterized in that for encrypting the certificate lock command using a security algorithm using the confirmed terminal information as a parameter. . In the method for protecting a certificate in a mobile communication terminal, Waiting for data reception through a radio network and receiving a certificate lock command through a data radio channel (DARC); Extracting the DRM information by decrypting the received certificate lock command; And A third step of changing DRM information of a certificate previously stored as the extracted DRM information How to protect the certificate of the lost mobile communication terminal using a data radio channel comprising a. The method of claim 6, The DRM information inserted in the certificate lock command includes a DRM valid period or a DRM remaining number of times of use of a certificate previously stored in a mobile communication terminal. How to protect a certificate. The method of claim 6, The DRM information changed in the third step is recorded in the certificate file on the mobile communication terminal or recorded in a specific storage area on the mobile communication terminal to match the certificate of the lost mobile communication terminal. How to protect a certificate. The method according to any one of claims 6 to 8, In the second step, the certificate lock command decryption process uses a terminal information of its own (mobile communication terminal) as a parameter to decrypt the certificate lock command with a security algorithm. How to protect a certificate. The method of claim 9, In the second step, if the decryption fails with the terminal information of the mobile terminal as a result of performing the certificate lock command decryption process, the received certificate lock command is discarded using the data radio channel. To protect the certificate of a mobile terminal. Receiving a certificate lock service by receiving DRM information from a subscriber who lost the mobile communication terminal at a terminal loss processing server; Checking, by the terminal loss processing server, the terminal information of the subscriber with reference to the received matters of the subscriber, and binding the terminal information and the received DRM information to generate an encrypted certificate lock command; Forwarding the generated certificate lock command to the radio broadcasting center by the terminal loss processing server and instructing the transmission; Waiting for data reception through a radio network in a mobile communication terminal and receiving a certificate lock command through a data radio channel (DARC); Extracting DRM information by decrypting the received certificate lock command in a mobile communication terminal; And Changing DRM information of a certificate previously stored in the extracted DRM information in a mobile communication terminal; How to protect the certificate of the lost mobile communication terminal using a data radio channel comprising a.

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