Patent Publication Number: US-11386196-B1

Title: Content wallet device and self-sovereign identity and copyright authentication system using the same

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a National Stage of International Application No. PCT/KR2020/016341, filed Nov. 19, 2020, claiming priority to Korean Patent Application No. 10-2019-0169407, filed Dec. 18, 2019, the entire disclosures of which are incorporated herein by reference. 
     TECHNICAL FIELD 
     The present disclosure relates to a content wallet device and a system using the same, and more particularly, to a content wallet device in which security of content information is enhanced by newly generating a password required for self-sovereign identity authentication, and a system using the same. 
     BACKGROUND ART 
     It is common for private business operators who want to operate an online platform to operate their businesses by entrusting an operator who operates a centralized database with data management regarding personal information required for membership registration and platform use history, and the right to use the corresponding information. 
     In a case where a private online platform operated with the centralized database as such is hacked by a third party, there is a problem that data of other users who use the private online platform in common may be easily leaked. 
     In addition, when private business operators who want to operate a personal online platform use the private online platform, they should not only pay a high fee for use of the private online platform, but may also quickly cope with a problem occurring in personal data management. 
     DISCLOSURE 
     Technical Problem 
     An object of the present disclosure is to provide to a content wallet device capable of allowing a user to directly transmit a content stored in a storage device to a purchaser who wants to purchase the content without the intervention of a central management server and enhancing security by generating a new password whenever user authentication is required so that hacking or leakage does not easily occur, and a system using the same. 
     Technical Solution 
     According to an embodiment of the present disclosure, a content wallet device to which a storage device storing a content is connected may include: a communication unit for communication between the content wallet device and a user terminal device; an encryption unit generating encryption data including a user ID and a password for authentication between the content wallet device and the user terminal device; a switch unit controlling an electrical connection between the storage device and the communication unit; and a reset unit initializing the generated password when the electrical connection between the storage device and the communication unit is released by the switch unit. 
     In this case, when the storage device and the communication unit are electrically connected to each other by the switch unit, the encryption unit may generate a first random password, when the electrical connection between the storage device and the communication unit is released by the switch unit, the reset unit may initialize the first random password, and when the storage device and the communication unit are electrically connected to each other again by the switch unit, the encryption unit may generate a second random password. 
     In addition, when the storage device and the communication unit are electrically connected to each other by the switch unit, the communication unit may transmit a signal for blocking a network of the user terminal device to the user terminal device. 
     Here, when the network of the user terminal device is blocked, the authentication may be performed between the content wallet device and the user terminal device through the encryption data generated by the encryption unit. 
     Furthermore, the encryption unit may encrypt the content and transmit the encrypted content to the communication unit, when the storage device and the communication unit are electrically connected to each other by the switch unit. 
     In addition, the encryption unit may insert an identification code unique to a user into the content. 
     According to another embodiment of the present disclosure, a system may include a content wallet device and a user terminal device, wherein the content wallet device transmits encryption data including a user ID and a password to the user terminal device for authentication between the content wallet device and the user terminal device, and the user terminal device performs the authentication between the content wallet device and the user terminal device when a password input according to a user&#39;s manipulation is matched with the transmitted password. 
     Here, the content wallet device may randomly generate and transmit a password for the authentication whenever the authentication between the content wallet device and the user terminal device is performed. 
     In addition, the content wallet device may transmit a signal for blocking a network of the user terminal device to the user terminal device when the storage device and the content wallet device are electrically connected to each other, and the user terminal device may block the network when a user&#39;s manipulation corresponding to the transmitted signal is input. 
     Advantageous Effects 
     As set forth above, according to various embodiment of the present disclosure, when a user sells a content, the user and a purchaser may directly sell and purchase the content, respectively, without transferring authority to a central management system, and by generating a new password whenever the user authenticates ownership of the content, a third party hacking may be prevented to prevent illegal leakage of the content. 
    
    
     
       DESCRIPTION OF DRAWINGS 
         FIG. 1  is a block diagram illustrating a configuration of a content wallet device according to an embodiment of the present disclosure. 
         FIG. 2  is a block diagram illustrating a configuration of a content wallet device according to another embodiment of the present disclosure. 
       (a) and (b) of  FIG. 3  are cross-sectional views for describing the content wallet device illustrated in  FIG. 2 . 
         FIG. 4  is a view for describing a state in which a content wallet device is embedded in a user terminal device according to another embodiment of the present disclosure. 
         FIG. 5  is a view for describing a state in which various storage devices are connected to a content wallet device according to another embodiment of the present disclosure. 
         FIG. 6  is a diagram for describing a system using a content wallet device according to an embodiment of the present disclosure. 
         FIG. 7  is a flowchart for describing a flow of the system using a content wallet device illustrated in  FIG. 6 . 
         FIG. 8  is a diagram for describing a system using a content wallet device according to another embodiment of the present disclosure. 
     
    
    
     BEST MODE FOR INVENTION 
     Hereinafter, the present disclosure will be described in more detail with reference to the accompanying drawings. In addition, in describing the present disclosure, when it is decided that a detailed description for known functions or configurations related to the present disclosure may obscure the gist of the present disclosure, the detailed description therefor will be omitted. Further, terms to be described later are defined in consideration of functions in the present disclosure and may be changed depending on the intention or relationship of users and operators. Therefore, these terms should be defined based on contents throughout the present specification. 
     A storage device  300  according to the present disclosure may be an independent storage device including a storage function, such as an external hard drive, a universal serial bus (USB), a compact disk (CD), or a memory card capable of storing a content, and it will hereinafter be described that the storage device is a memory card (hereinafter, denoted by  300  which is a reference numeral of the storage device), but the storage device is not limited thereto. 
       FIG. 1  is a block diagram illustrating a configuration of a content wallet device according to an embodiment of the present disclosure. 
     Referring to  FIG. 1 , the content wallet device  100  may be connected to a memory card  300  in which a content is stored, and may transmit the content stored in the memory card  300  to a user terminal device  200 . 
     In this case, the user terminal device  200  may be a mobile terminal device, but may be other electronic devices capable of performing electrical communication, such as a tablet personal computer (PC), a personal digital assistant (PDA), a wearable device, a laptop computer, a desktop PC, and a digital camera. 
     In addition, the content wallet device  100  may include a communication unit  110 , an encryption unit  120 , a switch unit  130 , a storage unit  140 , and a reset unit  150  in order to transmit the content. 
     The communication unit  110  enables communication between the content wallet device  100  and the user terminal device  200 , and communication may be performed through a direct connection in a wired manner or an indirect connection in a wireless manner within a predetermined range. 
     For example, in a connection between the user terminal device  200  and the content wallet device  100  in the wired manner, a manner of connecting the content wallet device  100  to a charging terminal generally used in the user terminal device  200  may be used. In addition, the user terminal device  200  and the content wallet device  100  may be directly connected to each other using a manner of connecting the content wallet device  100  to a terminal into which an external hard drive, a USB, an earphone, or the like, is inserted. 
     In the connection in the wireless manner, when the content wallet device  100  and the user terminal device  200  are positioned within a predetermined range, the content wallet device  100  and the user terminal device  200  may be indirectly connected to each other using near field communication (NFC), radio frequency identification (RFID), Bluetooth, infrared communication, and the like. 
     The content wallet device  100  and the user terminal device  200  are connected to each other by the communication unit  110  as such, such that the content stored in the memory card  300  inserted into the content wallet device  100  may be moved to the user terminal device  200 , and a password randomly generated for authentication in the content wallet device  100  may be moved to the user terminal device  200 . 
     Moreover, the communication unit  110  may transmit a signal for blocking a network of the user terminal device  200  to the user terminal device  200 , which will be described in detail below. 
     The encryption unit  120  may generate encryption data including a user identification (ID) and a password (pass-code) for authentication between the content wallet device  100  and the user terminal device  200 . 
     Specifically, the encryption unit  120  may generate the encryption data when the memory card  300  and the communication unit  110  are electrically connected to each other. 
     The user ID included in the encryption data may be a user authentication ID stored in the storage unit  140 , and may be, for example, an identity authentication ID by a decentralized identity (DID). 
     The DID is a self-sovereign identity verification technology based on a decentralized storage system, and the decentralized storage system is a method that does not delegate ownership of information that may identify an identity of an individual to a centralized system such as a specific institution or company and separately stores and manages information required for identity verification by end members of a network. 
     In other words, the self-sovereign identity verification technology is a manner in which individuals prove their sovereignty over identity verification information. 
     The encryption unit  120  may generate the DID as the encryption data together with a password by invoking the DID from the storage unit  140 . 
     In addition, the password included in the generated encryption data may be a password generated by mixing numbers, letters, symbols, or the like, with each other or generated by using a number of times of a touch, a pattern, a touch area designation, or the like. 
     For example, when the number of inputable digits of the generated password is 10, in a case where the user terminal device is a desktop PC, the password may be generated by mixing only numbers from 0 to 9 among numbers, letters, or symbols with each other or be generated by mixing Korean, English, and symbols written together with numbers above the numbers included in a typewriter with each other. 
     In addition, the password may be generated in the form of a pattern using a straight line or a curved line from the content wallet device to a screen of the desktop PC. 
     Furthermore, the encryption unit  120  may encrypt the content stored in the memory card  300  before the content is transmitted to the user terminal device  200 , and transmit the encrypted content to the communication unit  110 . This is that the encryption unit  120  encrypts the content when the memory card  300  and the communication unit  110  are electrically connected to each other by the switch unit  130 . 
     For example, the encryption unit  120  may encrypt the content in an analog manner using a pre-stored mechanism or encrypt the content in a digital manner using a pre-stored logical algorithm. 
     The encrypted content is encrypted according to a public key encryption manner or a private key encryption manner, and the encryption unit  120  may also generate a decryption key and transfer the generated decryption key to the communication unit  110  so that the encrypted content may be decrypted again. 
     In addition, the encryption unit  120  may exclude the encryption of the content and insert only an identification code unique to a user into the content so as to identify an original author of the content, in order to simplify a content encryption process. 
     For example, the identification code unique to the user may be formed through a watermark. The watermark is a technology of inserting a mark known only by the original author of the content, and in a case where a third party who was unauthorized illegally copies or distributes the content, the watermark inserted into the content may be extracted to confirm that the content is the content of the original author and may be used to track a path through which the content is copied. 
     The switch unit  130  may control an electrical connection between the memory card  300  and the communication unit  110 . 
     For example, the switch unit  130  is a button type whose position may be physically changed, and may include a toggle switch, a push button switch, a sliding button switch, and the like. 
     The switch unit  130  whose position may be physically changed as such may electrically connect the memory card  300  and the communication unit  110  to each other by moving in a direction in which the memory card  300  is inserted into the content wallet device  100  after the memory card  300  is inserted into the content wallet device  100 . Conversely, the switch unit  130  may release the electrical connection between the memory card  300  and the communication unit  110  by moving in an opposite direction to the direction in which the memory card  300  is inserted into the content wallet device  100 . 
     However, this is an embodiment for describing the present disclosure. Therefore, when communication between the content wallet device  100  and the user terminal device  200  is performed, a manner in which the memory card  300  and the communication unit  110  are automatically connected to each other in the content wallet device  100  rather than a manner of connecting the memory card  300  and the communication unit  110  to each other by physically adjusting the position of the switch unit  130  may be implemented. 
     In addition, when the memory card  300  and the communication unit  110  are electrically connected to each other by the switch unit  130 , the communication unit  110  may transmit the signal for blocking the network of the user terminal device  200  to the user terminal device  200 . 
     In a case where the user terminal device  200  is a mobile terminal device, the communication unit  110  may transmit a message asking whether or not to switch a mode of the mobile terminal device to an airplane mode to the mobile terminal device, and it may be selected by a user&#39;s manipulation whether or not to switch the mode of the mobile terminal device to the airplane mode. 
     Furthermore, when the network of the user terminal device  200  is blocked, authentication may be performed between the content wallet device  100  and the user terminal device  200  through the encryption data including the user ID and the password, generated by the encryption unit  120 . 
     Continuing to describe the mobile terminal device as an example, in a case where the switch of the mode of the mobile terminal device to the airplane mode is selected by the user, the network of the mobile terminal device may be blocked, and the encryption data generated by the encryption unit  120  may be transmitted to the mobile terminal device. 
     In this case, the user inputs the password included in the transmitted encryption data to the mobile terminal device, and in a case where the input password coincides with the password generated by the content wallet device  100 , data regarding copyright identification information for the stored content may be additionally recorded in the content wallet device  100 . 
     In addition, authentication of the user for the encrypted content is performed by confirming whether or not the password input to the mobile terminal device by a user&#39;s manipulation coincides with the password generated by the content wallet device  100 . As a result, self-sovereign identity authentication may be performed. 
     As described above, in a case where the user terminal device is the desktop PC, the desktop PC may receive the password generated by mixing only the numbers from 0 to 9 among the numbers, the letters, or the symbols with each other or the password generated by mixing Korean, English, and the symbols written together with the numbers above the numbers included in the typewriter with each other, and authentication may be performed by inputting a password corresponding to the password transmitted through the typewriter or other input device. 
     In addition, in a case of a pattern password, authentication may be performed by drawing a transmitted pattern password with a mouse or a touchable screen of the user terminal device to input the password. 
     Here, it may be confirmed in the storage unit  140  included in the content wallet device  100  whether or not the password transmitted by the encryption unit  120  and the password input by the user through the user terminal device  200  coincide with each other. 
     For example, it may be confirmed through a password authentication module or a password authentication program stored in the storage unit  140  whether or not the password transmitted by the encryption unit  120  and the password input by the user through the user terminal device  200  coincide with each other. 
     The storage unit  140  may include at least one of a read only memory (ROM), a random access memory (RAM), an erasable programmable read only memory (EPROM), an electrically erasable programmable read only memory (EEPROM), and a hard disk, and may be a storage medium including a non-volatile memory capable of storing data. 
     When the password generated in the content wallet device  100  through the storage unit  140  and the password input to the user terminal device  200  by the user&#39;s manipulation coincide each other, the user who is an owner of the user ID may inquire the content stored in the memory card  300  of the content wallet device  100  authenticated through the user terminal device  200 . 
     In addition, in a case where it is necessary to transmit the content to another external terminal device, the inquired content may be selected and transmitted from the content wallet device  100  to the user terminal device  200 , and the user terminal device  200  may then transmit the received content to another external terminal device. 
     Here, in a case where the selected content is transmitted from the content wallet device  100  to the user terminal device  200 , the selected content may be encrypted and then transmitted. Meanwhile, the content wallet device  100  may include a processor (not illustrated). In this case, the operation of the encryption unit  120  described above may be performed by the processor (not illustrated). In this case, the encryption unit  120  may be replaced by the processor (not illustrated). 
     The processor (not illustrated) may read a program stored in the password authentication module stored in the storage unit  140  to calculate whether or not the generated password and the password input to the user terminal device  200  by the user&#39;s manipulation coincide with each other. 
     In addition, the processor (not illustrated) may read a program stored in a content encryption module stored in the storage unit  140  to encrypt the content as described above. 
     The reset unit  150  may initialize the generated password when the electrical connection between the memory card  300  and the communication unit  110  is released by the switch unit  130 . 
     For example, when the memory card  300  is inserted into the content wallet device  100  and the switch unit  130  is moved in the direction in which the memory card  300  is inserted into the content wallet device  100 , the memory card  300  and the communication unit  110  are electrically connected to each other, such that the encryption unit  120  may generate a first random password. 
     Thereafter, when the switch unit  130  is moved in the opposite direction to the direction in which the memory card  300  is inserted into the content wallet device  100 , the first random password may be initialized by the reset unit  150  while the electrical connection between the memory card  300  and the communication unit  110  is released. 
     In this case, the first random password generated by the encryption unit  120  is stored in the storage unit  140 , and the first random password stored in the storage unit  140  may be initialized by the reset unit  150  while the electrical connection between the memory card  300  and the communication unit  100  is released by the switch unit  130 . 
     When the switch unit  130  is moved again in the direction in which the memory card  300  is inserted into the content wallet device  100 , the encryption unit  120  may generate a second random password different from the initialized first random password while the memory card  300  and the communication unit  110  are electrically connected to each other again, and the second random password may also be stored in the storage unit  140 . 
     In this way, whenever the content wallet device  100  and the user terminal device  200  are connected to each other, the encryption unit  120  may randomly generate a new password, and the previously randomly generated password may be initialized by the reset unit  150  to prevent a hacking risk by a third party. 
       FIG. 2  is a block diagram illustrating a configuration of a content wallet device according to another embodiment of the present disclosure, and (a) and (b) of  FIG. 3  are cross-sectional views for describing the content wallet device illustrated in  FIG. 2 . 
     Here, the communication unit  110 , the encryption unit  120 , the switch unit  130 , the storage unit  140 , and the reset unit  150  have already been described, and a detailed description thereof will thus be omitted. 
     Referring to  FIG. 2 , the content wallet device  100  may further include an input unit  160 . 
     The input unit  160  is for receiving a user&#39;s manipulation, and the password generated by the content wallet device  100  may be input and generated to the input unit  160  by the user&#39;s manipulation. 
     In other words, as an embodiment, the randomly generated password may be randomly generated through the encryption unit  120  while the memory card  300  and the communication unit  110  are electrically connected to each other by the switch unit  130  illustrated in  FIG. 1 , and as another embodiment, the password may be input and randomly generated by the user&#39;s manipulation through the input unit  160  illustrated in  FIG. 2 . 
     Since the password is generated by the user&#39;s manipulation, it will be natural that the password before being initialized by the reset unit  150  and the password after being initialized by the reset unit  150  may be the same as each other. 
     In this case, the encryption unit  120  illustrated in  FIG. 2  may encrypt the content stored in the memory card  300  and generate a decryption key for decrypting the encrypted content. 
     In addition, the encryption unit  120  may generate an identification code unique to the user so that the original author of the content may be identified. 
     Describing an operation of the content wallet device  100  with reference to  FIGS. 3A and 3B , the memory card  300  may be inserted into the content wallet device  100 , and the inserted memory card  300  may be connected to the encryption unit  120 . 
     In this case, when the switch unit  130  is moved in the direction in which the memory card  300  is inserted into the content wallet device  100 , the encryption unit  120  may generate a user ID by invoking the user ID stored in the storage unit  140  while the memory card  300  and the communication unit  110  are electrically connected to each other. 
     In addition, a password arbitrarily input by the user through the input unit  160  may be randomly generated, and at the same time, be stored in the storage unit  140 . 
     The password generated through the input unit  160  and the user ID generated through the encryption unit  120  may be transferred to the communication unit  110 . 
     The randomly generated password transferred to the communication unit  110  may be transmitted to the user terminal device  200 , and when the user inputs the randomly generated password through the user terminal device  200 , the content wallet device  100  receives the password input by the user through the communication unit  110 , and the storage unit  140  stores the received password. 
     In this way, the storage unit  140  may confirm whether or not the password randomly generated in the content wallet device  100  and the password input to the user terminal device  200  coincide with each other. 
     In a case where these passwords coincide with each other, the user may inquire the content stored in the memory card  300  through the user terminal device  200 . In addition, when the content is to be transmitted to an external terminal device, the encryption unit  120  may encrypt the content stored in the memory card  300  and transfer the encrypted content to the communication unit  110 , and the communication unit  110  may transmit the encrypted content to the external terminal device through the user terminal device  200 . 
     When the switch unit  130  is moved to the opposite direction to the direction in which the memory card  300  is inserted into the content wallet device  100 , the password stored in the storage unit  140  may be initialized by the reset unit  150 . 
     However, the content wallet device  100  illustrated in  FIGS. 3A and 3B  is an example for implementing the present disclosure, and thus, positions of components included in the content wallet device  100  may be changed according to user&#39;s use and convenience. 
       FIG. 4  is a view for describing a state in which a content wallet device is embedded in a user terminal device according to another embodiment of the present disclosure. 
     Referring to  FIG. 4 , the content wallet device  100  may be implemented in a form in which it is embedded in the user terminal device  200 . 
     In this case, communication between the content wallet device  100  and the user terminal device  200  is performed in a process in which the content wallet device  100  is inserted into the user terminal device  200 , and when the content wallet device  100  is completely inserted into the user terminal device  200 , the content wallet device  100  and the user terminal device  200  may be electrically connected to each other. 
     The content wallet device  100  and the user terminal device  200  are electrically connected to each other, and at the same time, the content wallet device  100  transmits a message for blocking an external communication network to the user terminal device  200 . 
     When the user inputs a selection to block the external communication network to the user terminal device  200 , the content wallet device  100  may randomly generate a password, and invoke a user ID stored in the content wallet device  100  and transmit the user ID to the user terminal device  200  together with the generated password. 
     In this case, the password transmitted to the user terminal device  200  is input by the user, and the content wallet device  100  matches the input password and the password randomly generated by the content wallet device  100  with each other to confirm whether or not the input password and the password randomly generated by the content wallet device  100  coincide with each other, encrypts the content stored in the memory card  300 , and transmits the encrypted content to the user terminal device  200 . 
     When the transmission of the encrypted content to the user terminal device  200  is completed, the inserted content wallet device  100  may be separated from the user terminal device  200  to the outside. 
     In this case, the randomly generated password may be initialized while the content wallet device  100  is separated from the user terminal device  200 . 
     As another example in which the content wallet device  100  is embedded in the user terminal device  200  and is implemented, a switch unit (not illustrated) whose position may be changed may be included on one surface of the content wallet device  100  exposed to the outside without being inserted when the content wallet device  100  is inserted into the user terminal device  200 . 
     Such a switch unit may be a toggle switch, a push button switch, a sliding button switch, and the like, and the electrical connection between the content wallet device  100  and the user terminal device  200  may be controlled by moving the switch unit. 
       FIG. 5  is a view for describing a state in which various storage devices are connected to a content wallet device according to another embodiment of the present disclosure. 
     Referring to  FIG. 5 , the content wallet device  100  may include a plurality of input/output ports, and various storage devices may be connected to the content wallet device  100  through the input/output ports. 
     In this case, the wallet device  100  including the plurality of input/output ports may be a docking station device such as USB or Thunderbolt. 
       FIG. 6  is a diagram for describing a system using a content wallet device according to an embodiment of the present disclosure. 
     Referring to  FIG. 6 , the system  10  using a content wallet device may include the content wallet device  100  and the user terminal device  200 . 
     The content wallet device  100  may transmit encryption data including a user ID and a randomly generated password to the user terminal device  200  for authentication between the content wallet device  100  and the user terminal device  200 . 
     The user terminal device  200  may perform the authentication between the content wallet device  100  and the user terminal device  200  when a password input according to a user&#39;s manipulation is matched with the transmitted password. 
     For example, the content wallet device  100  may transmit the randomly generated password to the user terminal device  200 , the user inputs the transmitted password through the user terminal device  200 , and the content wallet device  100  receiving the input password may match the input password and the randomly generated password with each other to confirm whether or not the input password and the randomly generated password coincide with each other. 
     Here, the randomly generated password may be newly generated whenever the content wallet device  100  and the user terminal device  200  perform the authentication, and the content wallet device  100  may confirm whether or not the newly generated password and the input password coincide with each other whenever the authentication is performed. 
     When the matched passwords coincide with each other, the content wallet device  100  may transfer the content and the user ID to the user terminal device  200 , and may directly transmit the encrypted content and a user ID together with a decryption key to a user terminal device  200 - 1  of another user who wants to purchase the content. 
     In this case, the user terminal device  200  may perform identity authentication by decentralized identities (DIDs) by transmitting the user ID transmitted from the content wallet device  100  to the user terminal device  200 - 1  of another user. 
     For example, when the user terminal device  200  that is to supply the content transmits a deactivated user ID (DID) and the encrypted content transmitted from the content wallet device  100  to the user terminal device  200 - 1  of another user, the user terminal device  200 - 1  of another user may perform user identity authentication for a corresponding individual demand to a supplier by transmitting a self-sovereign identity (SSI). To the contrary, another user inputs a password randomly generated through his/her content wallet device  100 - 1  to the user terminal device  200 - 1 , and may transmit a content owned by him/her to the user terminal device  200 - 1  and directly transmit the content to another user terminal device  200  when a password transferred from the content wallet device  100 - 1  and the password input by the user of the user terminal device  200 - 1  coincide with each other. 
     A third party hacking and illegal leakage of contents may be prevented by proving that different users owning the contents are legitimate users through the passwords randomly generated through the content wallet devices  100  and  100 - 1  and the user terminal devices  200  and  200 - 1  and then transmitting the user IDs and the contents. 
     Referring to  FIGS. 1 and 6 , the system  10  including the content wallet device  100  may transmit a signal for blocking a network of the user terminal device  200  to the user terminal device  200  when the memory card  300  and the content wallet device  100  are electrically connected to each other, and the user terminal device  200  may block the network when a user&#39;s manipulation corresponding to the transmitted signal is input. 
     In this case, the blocked network may be an external communication network of the user terminal device  200 , and may include, for example, a local area network (LAN), a metropolitan area network (MAN), and a wide area network (WAN), and the like. Specifically, for example, in a case where the user terminal device  200  is a mobile terminal device, the communication unit  110  may transmit a message asking whether or not to switch a mode of the mobile terminal device to an airplane mode to the mobile terminal device, and it may be selected by a user&#39;s manipulation whether or not to switch the mode of the mobile terminal device to the airplane mode. 
     In this case, when the user selects the switch of the mode of the mobile terminal device to the airplane mode, a network, which is an external communication network of the mobile terminal device, may be blocked, and only communication between the content wallet device  100  and the user terminal device  200  may be performed through a direct connection in a wired manner or an indirect connection in a wireless manner within a predetermined range. 
       FIG. 7  is a flowchart for describing a flow of the system using a content wallet device illustrated in  FIG. 6 . 
     Referring to  FIG. 7 , the system  10  using a content wallet device may sequentially perform a step (S 100 ) of inserting the memory card into the content wallet device, a step (S 200 ) of determining whether or not the inserted memory card and the content wallet device have been connected to each other, a step (S 300 ) of transmitting a signal for blocking a network from the content wallet device to the user terminal device, a step (S 400 ) of determining whether or not the network of the user terminal device has been blocked, a step (S 500 ) of transmitting encryption data from the content wallet device to the user terminal device, a step (S 600 ) of confirming whether or not randomly generated passwords between the content wallet device and the user terminal device coincide with each other, and a step (S 700 ) of encrypting a content by the content wallet device and transmitting the encrypted content from the content wallet device to the user terminal device. 
     The step (S 100 ) of inserting the memory card into the content wallet device is a step of inserting the memory card in which the content is stored into the content wallet device. Then, the step (S 200 ) of determining whether or not the inserted memory card and the content wallet device have been connected to each other may be performed. 
     In this case, the step (S 200 ) of determining whether or not the inserted memory card and the content wallet device have been connected to each other may be a step of confirming whether or not the memory card and the content wallet device have been electrically connected to each other due to a physical change. 
     In a case where the memory card and the content wallet device have not been electrically connected to each other, the system using a content wallet device does not perform a procedure of transmitting the content to the user terminal device. 
     On the other hand, when the memory card and the content wallet device have been electrically connected to each other, the step (S 300 ) of transmitting the signal for blocking the network from the content wallet device to the user terminal device may be performed. 
     The step (S 300 ) of transmitting a signal for blocking a network from the content wallet device to the user terminal device may be a step of transmitting the signal for blocking the network, which is an external communication network used by the user terminal device for communication with other electronic devices. 
     When the signal for blocking the network is normally transmitted to the user terminal device, it may be selected by a user&#39;s manipulation whether or not to block the network. 
     The step (S 400 ) of determining whether or not the network of the user terminal device has been blocked may be a step of determining whether or not the network of the user terminal device has been normally blocked when the blocking of the network is selected by the user&#39;s manipulation. 
     When the network of the user terminal device has not been normally blocked, the system using a content wallet device may return to the step (S 200 ) of determining whether or not the inserted memory card and the content wallet device have been connected to each other to determine whether or not the inserted memory card and the content wallet device have been connected to each other. 
     On the other hand, when the network of the user terminal device has been normally blocked, the step (S 500 ) of transmitting encryption data from the content wallet device to the user terminal device may be performed. 
     In this case, the encryption data may be data including a user ID and a randomly generated password. 
     The step (S 500 ) of transmitting encryption data from the content wallet device to the user terminal device may be a step of randomly generating a password and transmitting the randomly generated password to the user terminal device by the encryption unit included in the content wallet device when the memory card and the content wallet device are normally connected to each other. 
     In this case, the user ID as well as the randomly generated password may be transmitted to the user terminal device. 
     When the randomly generated password is transmitted to the user terminal device as described above, the step (S 600 ) of confirming whether or not the randomly generated passwords between the content wallet device and the user terminal device coincide with each other may be performed. 
     In the step (S 600 ) of confirming whether or not the randomly generated passwords between the content wallet device and the user terminal device coincide with each other, when the randomly generated password transmitted to the user terminal device is input to the user terminal device by a user&#39;s manipulation, the input password is transmitted to the content wallet device, and the transmitted password is matched with the randomly generated password in the content wallet device. 
     When the matched passwords do not coincide with each other, the step (S 200 ) of determining whether or not the inserted memory card and the content wallet device have been connected to each other may be performed, and the previously randomly generated password may be initialized and another password may be randomly generated while an electrical connection between the memory card and the content wallet device is newly made. 
     On the other hand, when the matched passwords coincide with each other, the step (S 700 ) of encrypting the content by the content wallet device and transmitting the encrypted content from the content wallet device to the user terminal device may be performed. 
     The step (S 700 ) of encrypting the content by the content wallet device and transmitting the encrypted content from the content wallet device to the user terminal device may be a step of transmitting the encrypted content together with a decryption key capable of decrypting the encrypted content so that another user to which an original author of the content is to transmit the content and a user who normally purchases the content may use the content, simultaneously with encrypting the content stored in the memory card. 
     In this case, the encrypted content may be transmitted in a state in which an identification code unique to the user is inserted into the encrypted content, in order to identify the original author of the content. 
       FIG. 8  is a diagram for describing a system using a content wallet device according to another embodiment of the present disclosure. 
     Referring to  FIG. 8 , the system  10  using a content wallet device may directly transmit contents between users who own user terminal devices  200 ,  200 - 1 ,  200 - 2 ,  200 - 3 ,  200 - 4 , and  200 - 5  for free or for a fee, but the user may easily receive desired contents by using content wallet devices  100 ,  100 - 1 ,  100 - 2 ,  100 - 3 ,  100 - 4 , and  100 - 5  for a plurality of user terminal devices  200 ,  200 - 1 ,  200 - 2 ,  200 - 3 ,  200 - 4 , and  200 - 5 . 
     In this case, when any one of the plurality of user terminal devices  200 ,  200 - 1 ,  200 - 2 ,  200 - 3 ,  200 - 4 , and  200 - 5  performs user authentication through the content wallet device  100  and then transmits an encrypted content to a network, the network may provide a preview or related information of the encrypted content. 
     Then, in a case where a plurality of users view the preview or the related information of the encrypted content through their own user terminal devices  200 - 1 ,  200 - 2 ,  200 - 3 ,  200 - 4 , and  200 - 5  and want to purchase the encrypted content, the plurality of users make payment for the encrypted content, and when the payment is completely made, an original author who owns the encrypted content may transmit the encrypted content and a decryption key together to the other user terminal devices  200 - 1 ,  200 - 2 ,  200 - 3 ,  200 - 4 , and  200 - 5 . 
     Here, purchase histories, transmission histories, and the like, between the user terminal devices  200 ,  200 - 1 ,  200 - 2 ,  200 - 3 ,  200 - 4 , and  200 - 5  that use the content wallet devices  100 ,  100 - 1 ,  100 - 2 ,  100 - 3 ,  100 - 4 , and  100 - 5  may be performed and stored by a distributed ledger. 
     The distributed ledger may be based on a generally used blockchain, and all the exchange histories of the content using the content wallet device  100  according to the present disclosure may be stored by using the distributed ledger. 
     In addition, the distributed edger may store information on a user who creates the purchase history, the transmission history, and the like, through a user ID transmitted from each of the content wallet devices  100 ,  100 - 1 ,  100 - 2 ,  100 - 3 ,  100 - 4 , and  100 - 5 . 
     In this case, as described above, the used user ID is a user authentication ID owned by the user of each of the content wallet devices  100 ,  100 - 1 ,  100 - 2 ,  100 - 3 ,  100 - 4 , and  100 - 5 , that is, a decentralized ID (DID). 
     Accordingly, each of the users may view all histories stored by the decentralized ledger, and it may be easily known which users have made purchases, transmissions, and the like, such that transparent transactions are possible. 
     In addition, the user may directly manage a user authentication method in which the identity information was managed by a central server by using the DID. 
     In other words, for example, when the content stored in the memory card is a moving image, a decentralized ID (DID) required for identity authentication of the user may be transmitted from the user terminal device  200  that is to supply the moving image to the user terminal devices  200 - 1 ,  200 - 2 ,  200 - 3 ,  200 - 4 , and  200 - 5  that are to purchase the moving image. 
     Thereafter, when the user terminal devices  200 - 1 ,  200 - 2 ,  200 - 3 ,  200 - 4 , and  200 - 5  that are to purchase the moving image transmit identity authentication values (SSIs), such that identity authentication of users is established, the moving image may be encrypted in which it is not completely disclosed, and be transmitted to the user terminal devices  200 - 1 ,  200 - 2 ,  200 - 3 ,  200 - 4 , and  200 - 5  that are to purchase the moving image together with a decryption key. 
     In this process, all of supply records of the user terminal device  200  that has supplied the moving image, purchase histories of the user terminal devices  200 - 1 ,  200 - 2 ,  200 - 3 ,  200 - 4 , and  200 - 5  that are to purchase the moving image, and the like, may be stored in distributed ledger data by each of the user terminal devices  200 - 1 ,  200 - 2 ,  200 - 3 ,  200 - 4 , and  200 - 5 . 
     Although embodiments of the present disclosure have been illustrated and described hereinabove, the present disclosure is not limited to the above-mentioned specific embodiments, but may be variously modified by those skilled in the art to which the present disclosure pertains without departing from the scope and spirit of the present disclosure as disclosed in the accompanying claims. These modifications should also be understood to fall within the scope of the present disclosure.