KR20070105598A - Protecting method and system of contents - Google Patents

Abstract

A method and a system for protecting contents are provided to prevent access to contents from the outside even if a member shop directly keeps the contents by protecting hacking and download probability generated when a head office provides various kinds of contents to the member shop through the Internet. A data receiver(140) receives data if the data is received from a member shop server through a web server(300) and provides the received data to a controller(130). A contents extractor(120) searches and extracts a contents file stored in a main database(200) by a command of the controller. A data transmitter(150) provides the extracted contents file to the member shop server through the web server. A remote controller(160) remotely controls the member shop server if a signal reporting a computer trying to access the member shop server in a not predetermined mode is received. A member manager(110) authenticates authentication information of the member shop by comparing the authentication information received from the member shop with member information stored in the main database.

Description

{Protecting method and system of contents}

1 is a schematic illustration of a content protection system in accordance with the present invention;

2 is a view schematically showing the configuration of the main server shown in FIG. 1;

3 is a view schematically showing the configuration of the main DB shown in FIG. 1;

4 is a diagram schematically illustrating a configuration of an affiliated store server illustrated in FIG. 1;

FIG. 5 is a diagram schematically illustrating a configuration of an affiliated store DB shown in FIG. 1;

6 is a diagram showing a content protection method according to the first embodiment of the present invention;

7 illustrates a content protection method according to a second embodiment of the present invention; And

8 is a diagram illustrating a content protection method according to a third embodiment of the present invention.

The present invention provides a method and system for protecting contents, and more specifically, in the business model in which the head office provides contents to merchants and the merchants generate revenue using the provided contents, external hacking may occur when the contents are provided online. The invention relates to a content protection method and system that solves security vulnerabilities.

Recently, due to the development of multimedia technology, various types of leisure facilities such as video room, DVD room, karaoke room, and game room have been created, and these spaces are used by many people for the purpose of leisure use and social gathering. Facilities are increasingly franchised to generate stable revenue through effective marketing. The franchise for these recreational facilities usually consists of a relationship between the head office and the affiliated store (chain store), which unites the interior of each affiliated store and provides or purchases various hardware equipment such as karaoke machines, DVD players and computer devices. In particular, contents that meet the characteristics of each franchise are collectively provided.

On the other hand, the content has been provided offline using tools such as videotape and CD-ROM titles in the past, but with the recent development of the Internet technology, a technology that can transfer a large amount of files in a short time has been developed. As storage capacity has increased dramatically, there has been a tendency to provide various contents through online download methods, and to store the received contents in various storage media such as hard disk drives. In the case of providing contents by using online upload / download method, since there is no need for a separate tool for storing contents, the cost of purchasing content is relatively low, and in addition to having a small computer at the merchant, it is possible to store separate contents. There is no need for space, and downloads can be done in real time, greatly reducing the burden of having to purchase a lot of content in the beginning.

However, in the case of providing the content by such upload / download method, the computer installed in the affiliated store is difficult to have expensive security device, so the security against the external hacking is relatively weak, so that the computer terminal installed in the external or affiliated store There is a disadvantage that it is easy to hack a merchant server to copy various contents without permission. In addition, the hacked content can be duplicated with the same quality regardless of the number of times, so that those who have the authority to permit the use of various contents, such as copyright holders, are reluctant to supply the contents through the franchise.

On the other hand, in order to prevent such problems such as illegal downloads, services that provide various content in a streaming manner has recently increased. The streaming method is a technology that can reproduce the transmitted data in real time without interruption, and when using this method, users can use various data on the Internet in real time without storing it on their PCs. As such, when the streaming method is used to prevent the problem of illegal download, the client stores all the contents on the server or the storage device of the headquarters, and if the request for the use of the contents is requested from the client computer connected to the merchant server, the client immediately stores the contents through the merchant server. Transfer to a computer (or directly from our server to a client computer).

However, in this case, all contents are stored only in the server or DB of the head office. Therefore, if the user wants a large amount of service such as a DVD movie file, it takes a considerable time to transfer. Due to the drop in speed and forced termination of access, there is a limit to using the desired content comfortably. In addition, in such a streaming method, since the user cannot use the functions such as quick view and replay, the user has a limit in freely using the content selected by the user.

The present invention is to block the possibility of illegal hacking, download that can occur when the headquarters supply various content to the merchants, especially the headquarters using the content of the conventional franchise that the merchants have the content directly In this case, an object of the present invention is to provide a method and system for protecting content that can block access to the content from the outside.

In addition, an object of the present invention is to provide a content protection method and system that allows each merchant to store the content directly so that users who visit the merchant can use various contents in various ways.

In addition, an object of the present invention is to provide a content protection method and system that allows the owners of content, such as copyright holders to conclude a content supply contract with confidence by blocking the possibility of hacking from the outside, even though the merchant owns the content directly. do.

A content protection method according to a preferred embodiment of the present invention for achieving the above object comprises the steps of: detecting a computer attempting to connect in a manner other than the predetermined method; Providing a signal to the main server that there is a computer attempting to connect to the merchant server in a manner other than the predetermined method; Receiving whether or not the remote control program is executable from the main server; And upon receiving a signal that the remote control program can be executed, proceed with at least one of the process of shutting down the affiliate server and the process of destroying the content file stored in the affiliate DB under the control of the main server, and receiving a signal that the remote control program cannot be executed. And a process of destroying the content file stored in the merchant DB.

In this case, the main server or the affiliate server may further include transmitting at least one access warning message to the computer before executing the affiliate server termination process or destroying the content file.

A protection method according to another embodiment of the present invention for achieving the above object comprises the steps of: detecting a computer attempting to connect by a method other than a predetermined promised method; And checking whether the server is online or offline with the main server, and when the server is online with the main server, a signal indicating that there is a computer attempting to connect to the affiliate server through a method other than the predetermined method. Providing to a server; Receiving whether or not the remote control program is executable from the main server; And receiving a signal indicating that the remote control program can be executed, proceeding at least one of the process of destroying the merchant server and the content file stored in the merchant DB under the control of the main server, and receiving a signal that the remote control program cannot be executed. Destructing the content file stored in the merchant DB, and if the offline state with the main server, characterized in that it comprises the step of destroying the content file stored in the merchant DB.

In addition, in this case, when offline with the main server, it is preferable to further include the step of requesting to provide a predetermined authentication signal to the computer before the step of destroying the content file stored in the merchant DB.

In this case, the main server or the affiliate server may further include transmitting at least one access warning message to the computer before executing the affiliate server termination process or destroying the content file.

A protection method according to another embodiment of the present invention for achieving the above object comprises the steps of: detecting a computer attempting to connect by a method other than a predetermined promised method; Determining whether the server is online or offline with the main server,

Providing a signal to the main server that there is a computer attempting to connect to the affiliated server in a manner other than the predetermined method when the server is online with the main server; Receiving whether or not the remote control program is executable from the main server; And upon receiving a signal that the remote control program can be executed, proceed to at least one of the process of closing the affiliate server and the content file stored in the affiliate DB under the control of the main server, and executing the remote control program. Receiving a signal, destroying the content file stored in the merchant DB,

Requesting to provide a predetermined authentication signal to the computer when offline with the main server, and receiving the possibility of executing the remote control program from the main server when the predetermined authentication signal is not provided from the computer; And receiving a signal indicating that the remote control program can be executed, proceeding at least one of the process of destroying the merchant server and the content file stored in the merchant DB under the control of the main server, and receiving a signal that the remote control program cannot be executed. And destroying the content file stored in the merchant DB.

In this case, the main server or the affiliate server may further include transmitting an access warning message to the computer before executing the affiliate server termination process or destroying the content file.

On the other hand, the content protection system according to the present invention stores the content files and other files provided from the main server and the main server, using the main DB and wired and wireless communication network to provide the stored files to the main server and a plurality of merchant server Includes a web server that provides connectivity for

The main server may include: a data receiver configured to receive the input data and provide the received data to a controller when predetermined data is input from the affiliated store server through the web server; A content extraction unit searching for a content file stored in the main DB and extracting the retrieved content file according to a command of a controller; A data transmission unit providing the extracted content file to the affiliated store server through the web server; A remote control unit for remotely controlling the affiliate server which transmits the signal when a signal indicating that there is a computer attempting to access the affiliate server is received from the affiliate server in a manner other than a predetermined method; And a control unit controlling functions of the content extraction unit, the remote control unit, the data receiving unit, and the data transmitting unit.

In addition, the content protection system according to the present invention, if the authentication information of the member member is provided through the at least one affiliated server server compares the authentication information of the member member of the merchant with the member information stored in the main DB, each member member It is preferable to further include a member management unit for providing a state of the state and the state of the merchant server to the controller.

In addition, the content protection system according to the present invention stores a variety of files including the content files provided from the merchant server and the merchant server, and provides a control server and the control server using a merchant DB and wired and wireless communication network to provide the stored files and data to the merchant server; Includes a web server providing a connection to the merchant server,

The affiliated store server may include: a data receiving unit configured to receive the input file and provide the received file to a controller when a predetermined file is input from the main server through the web server; A content transmission unit providing the extracted content to the client computer; A content security unit configured to proceed with the termination process of the affiliate server under the control of the main server or to destroy the content file stored in the affiliate store DB under a predetermined condition; A content inlet / out unit for providing the decoded file to an affiliated store DB and extracting a file provided to an affiliated store DB; A data transmitter which provides various data to a main server through the web server; And a control unit for controlling functions of the decoding unit, the content fetching unit, the content transmitting unit, the content managing unit, the data receiving unit, and the data transmitting unit.

Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings. For reference, components having the same function have the same reference numerals, and the following embodiments are only one of the best forms constituting the present invention, and the scope of the present invention is not limited to the following embodiments. .

1 is a view schematically showing a content protection system according to a preferred embodiment of the present invention. As shown in FIG. 1, the content protection system according to the present embodiment stores a content file and other files provided by the main server 100 and the main server 100, and provides the stored DB to the main server 200. Franchise headquarters side system comprising a main server 100 and a web server 300 that provides a connection between a plurality of affiliated server servers 401, 402,..., And a main server using a wired / wireless communication network 700. Merchant server (401, 402, ..., hereinafter 400) for transmitting and receiving various files, such as content files from the 100, Merchant DB (501, 502, ..., which stores the content file, etc. provided from the main server) Hereinafter, a variety of transmissions are made from an affiliated store side system and an affiliated store server including a web server (not shown) that provides a connection between the main server 100 and a plurality of affiliated server servers 400 using the wired / wireless communication network 700. Client computer running content files It consists of (611, 612, 621, 622, ..., 600 or less).

Specifically, as shown in FIG. 2, when predetermined data is input from the affiliate server 400 through the web server 300, the main server 100 receives the input data and provides the received data to the controller. Receiver 140; When the authentication information of the affiliated member and / or the individual member is provided through the affiliated server server 400, the information is compared with the information of the affiliated member and the member stored in the main DB 200 and then the state of each member is provided to the controller 130. Member management unit 110; A content extraction unit 120 for searching for a content file stored in the main DB 200 and extracting the retrieved content file according to a command of the controller 130; A remote control unit 160 for remotely controlling the affiliate server which transmits the signal when a signal indicating that there is a computer attempting to connect to the affiliate server is received from the affiliate server 400 in a manner other than a predetermined method; A data transmitter 150 for providing the extracted content file to the affiliate server 400 through the web server 300; And a controller 140 for controlling functions of the member manager 110, the content extractor 130, the data receiver 140, the data transmitter 150, and the remote controller 160. On the other hand, when the remote control unit 160 receives a signal from the merchant server 400 that there is a computer attempting to connect to the merchant server by a method other than the predetermined method, the computer is no longer allowed to access. Sending an access warning message, forcibly terminating the merchant server 400 by using a remote control program, forcibly destroying (deleting) various content files stored in the merchant DB 500, etc. It is possible to prevent the external computer accessing 400 from copying various content files stored in the affiliated store DB.

In addition, as shown in Figure 3, the main DB 200 is a member of the individual stores the personal information such as the member's name, ID, password, personal details of each member, and in the case of the member is a member of the member's personal information Member information DB 210 that stores server information such as hardware information of merchant server DB and information of merchant DB, content DB 220 storing all content files that can be transmitted to a plurality of merchant servers, and distributed to each merchant server And a content list DB 230 for storing a list of content to be performed and a list of contents stored in the current content DB.

In addition, as shown in FIG. 4, when a predetermined file such as a content file is input from the main server 100 through the web server (not shown), the affiliate server 400 receives the input file and controls the received file. A data receiving unit 410 provided with; A content entry / exit unit 450 for providing the content file to the affiliated store DB 500 and extracting the file provided to the affiliated store DB 500; A content transmitter 430 for providing the extracted content to the client computer; Through the web server, various data generated from the merchant server 400, such as a member information and a computer that attempts to access the merchant server in a manner other than the predetermined method from the merchant server 400, are notified of this. A data transmitter 420 provided to the server 100; A content security unit 460 which proceeds with the termination process of the affiliate store server 400 under the control of the remote control unit 160 or destroys the content file stored in the affiliate store DB 400 under a predetermined condition to be described later; And a controller 440 for controlling the functions of the various components.

In addition, as shown in Figure 5, the merchant DB 500 is a member information DB 510 that stores personal information such as the name, ID, password, personal details of each member for the individual member; A content DB 520 for storing all content files provided from the main server 100; And a content list DB 530 that stores a list of content files currently stored in the predetermined affiliate store DB 430 and a list of content files stored in the main DB 200, and the like.

A detailed configuration of the system of the present embodiment having the above configuration and various embodiments of a method of distributing content using the system will be described below. For reference, components that perform the same functions as those described with reference to FIGS. 1 to 5 will be described using the same reference numerals.

A content protection method according to a first embodiment of the present invention will be described below with reference to FIG.

First, when an external computer that is not a client computer accesses the affiliated store server 400, or accesses the affiliated store server 400 in a manner not previously promised as the client computer 600, the affiliated store server 400 accesses the access. Information is provided to the main server 100 (S101). When the main server 100 receives the information that the external computer or the like approaches the affiliated server 400, the main server 100 transmits a message requesting the access to the corresponding external computer to be stopped once or several times (S102). In spite of the above message, when the access to the affiliated store server 400 is continued by an external computer or the like, the main server 100 operates a remote control process (S103). The main server 100 determines whether it is possible to directly control the affiliate server 400 by a remote control process (S104), and if the remote control is possible, proceeds with a process of forcibly terminating the affiliate server 400 (S105). . Subsequently, the merchant server 400 checks whether it is completely terminated (S106), if the merchant server 400 is not terminated, continues the forced termination process, and terminates the remote control process when the merchant server 400 ends. Let's do it.

On the other hand, when the remote control by the main server 100 is not possible in S104, and access to the affiliated store server 400 is continued by an external computer, the protection program by the affiliated store server 400 operates. That is, the affiliated store server 400 forcibly destroys the content file stored in the affiliated store DB 500 by a program stored therein (S107). The merchant server 400 checks whether all the content files stored in the merchant DB 500 are destroyed (S108), and if all are not destroyed, continues the destruction procedure, and if all are destroyed, terminates the forced destruction program.

Next, a content protection method according to a second embodiment of the present invention will be described below with reference to FIG.

First, when an external computer other than the client computer accesses the affiliate server 400, or accesses the affiliate server 400 in a manner not previously promised as the client computer 600, the affiliate server 400 is the main server. Check the connection with the 100 (S201).

In this embodiment, when the affiliate server 400 is online with the main server 100, access by such an external computer is controlled by the main server 100. That is, when the main server 100 receives the information that the external computer or the like approaches the merchant server 400 (S202), the main server 100 transmits a message for requesting the access stop to the corresponding external computer once or several times (S203). In spite of the message, when the access to the affiliated store server 400 is continued by an external computer or the like, the main server 100 operates a remote control process (S204). The main server 100 determines whether it is possible to directly control the affiliate server 400 by a remote control process (S205), and if the remote control is possible, proceeds to forcibly terminate the affiliate server 400 (S206). . Subsequently, the merchant server 400 checks whether it is completely terminated (S207), if the merchant server 400 is not terminated, continues the forced termination process, and terminates the remote control process when the merchant server 400 ends. Let's do it.

On the other hand, when the remote control by the main server 100 is not possible in S104, and access to the affiliated store server 400 is continued by an external computer, the protection program by the affiliated store server 400 operates. That is, the affiliated store server 400 forcibly destroys the content file stored in the affiliated store DB 500 by a program stored therein (S211). The merchant server 400 checks whether all the content files stored in the merchant DB 500 are destroyed (S212), and if all are not destroyed, continues the destruction procedure, and if all are destroyed, terminates the forced destruction program.

In addition, if the merchant server 400 and the main server 100 is not connected through the communication network in S201, the protection program by the merchant server 400 operates. In this case, the affiliated store server 400 first transmits a message for requesting an administrator authentication signal and an access stoppage to an external computer or the like once or several times (S208). If the administrator authentication according to the administrator authentication signal request (S209), the merchant server checks whether the authentication is correct (S210), and terminates the protection program if it is determined that the right owner's access. On the other hand, if the server administrator according to S209 is not authenticated or is determined to be unauthorized access, the merchant server 400 forcibly destroys the content file stored in the affiliated store DB 500 by a program stored therein (S211). The merchant server 400 checks whether all the content files stored in the merchant DB 500 are destroyed (S212), and if all are not destroyed, continues the destruction procedure, and if all are destroyed, terminates the forced destruction program.

Next, a content protection method according to a third embodiment of the present invention will be described below with reference to FIG.

First, when an external computer other than the client computer accesses the affiliate server 400, or accesses the affiliate server 400 in a manner not previously promised as the client computer 600, the affiliate server 400 is the main server. Check the connection state with (100) (S301).

In this embodiment, when the affiliate server 400 is online with the main server 100, access by such an external computer is controlled by the main server 100. That is, when the main server 100 receives the information that the external computer or the like approaches the affiliated store server 400 (S302), the main server 100 transmits a message requesting to stop the access to the corresponding external computer once or several times (S303). In spite of the message, if the access to the affiliated store server 400 is continued by an external computer or the like, the main server 100 operates a remote control process (S304). After determining whether the main server 100 can directly control the affiliate server 400 by a remote control process (S305), if the remote control is possible, the main server 100 performs a process of forcibly terminating the affiliate server 400 (S306). . Subsequently, the merchant server 400 checks whether it is completely terminated (S307), if the merchant server 400 is not terminated, continues the forced termination process, and terminates the remote control process when the merchant server 400 ends. Let's do it.

On the other hand, if the remote control by the main server 100 is impossible in S305, and access to the affiliated store server 400 is continued by an external computer, the protection program by the affiliated store server 400 operates. That is, the affiliate server 400 forcibly destroys the content file stored in the affiliate store DB 500 by a program stored therein. The merchant server 400 checks whether all the content files stored in the merchant DB 500 are destroyed (S312), and if all are not destroyed, continues the destruction procedure, and if all are destroyed, terminates the forced destruction program.

In addition, when the merchant server 400 and the main server 100 are not connected through the communication network in S301, the protection program by the merchant server 400 operates. In this case, the affiliated store server 400 first transmits a message for requesting an administrator authentication signal and an access interruption to an external computer or the like once or several times (S308). If the administrator authentication according to the administrator authentication signal request (S309), the merchant server checks whether the authentication is correct (S310), and terminates the protection program if it is determined that the right owner's access. On the other hand, if the server administrator according to S309 is not authenticated or is determined to be unauthorized access, the merchant server 400 requests the execution of the remote control process of the main server 100 again (S304), and proceeds to steps S305 to S307. Let's do it.

Meanwhile, in the present embodiment, the protection program by the main server is configured to forcibly terminate the affiliate server, and the protection program by the affiliate server is configured to destroy all contents stored in the affiliate DB, but the main server and the affiliate server are All can freely choose forced termination and / or content destruction to form a protection program. In addition, the affiliate server itself may execute various kinds of protection programs such as forced termination and content destruction of the affiliate server without remote control of the main server.

The content protection method and system according to the preferred embodiment of the present invention have been described in detail above. However, the configuration of the embodiment is to illustrate a specific method using the present invention, those of ordinary skill in the art will recognize that various modifications and changes are possible from this embodiment. Therefore, the scope of the present invention is not limited to the scope of the above embodiments, but only by the claims described later.

According to the content protection method according to the present invention, when access to the merchant server by an unscheduled computer in the first place, the server can be forcibly terminated or destroyed, thereby effectively preventing unauthorized copying of the content due to external intrusion. In addition, even if the content is destroyed in this way, the destroyed content can be retransmitted through the main server, so the merchants are provided with a safe protection device for their own content without any additional cost due to the content destruction.

Claims (8)

Detecting a computer attempting to connect in a manner other than the predetermined promised method; Providing a signal to the main server that there is a computer attempting to connect to the merchant server in a manner other than the predetermined method; Receiving whether or not the remote control program is executable from the main server; And Upon receiving the signal that the remote control program can be executed, at least one of the process of terminating the affiliate server and the process of destroying the content file stored in the affiliate DB is performed under the control of the main server, and the signal indicating that the remote control program cannot be executed. When receiving the content protection method comprising the step of proceeding to destroy the content file stored in the merchant DB. Detecting a computer attempting to connect in a manner other than the predetermined promised method; And Determining whether the server is online or offline with the main server, When the server is online with the main server, providing a signal to the main server indicating that there is a computer attempting to connect to the affiliate server in a manner other than the predetermined method; Receiving whether or not the remote control program is executable from the main server; And upon receiving a signal that the remote control program can be executed, proceed with at least one of a process of terminating a merchant server and a process of destroying a content file stored in the affiliate DB under the control of the main server, and cannot execute the remote control program. Receiving a signal, destroying the content file stored in the merchant DB, When the offline state with the main server, Content protection method comprising the step of destroying the content file stored in the merchant DB. The method of claim 2, further comprising: requesting to provide a predetermined authentication signal to the computer before the step of destroying the content file stored in the affiliated store DB when the offline state is established with the main server. Protection method. Detecting a computer attempting to connect in a manner other than the predetermined promised method; And checking whether the main server is online or offline. When the user is online with the main server, providing a signal to the main server that there is a computer attempting to connect to the affiliate server in a manner other than the predetermined method; Receiving whether or not the remote control program is executable from the main server; And upon receiving a signal that the remote control program can be executed, proceed with at least one of a termination process of an affiliated store server and a destruction process of a content file stored in an affiliated store DB under the control of the main server, and the remote control program can be executed. Destroying a content file stored in the affiliated store DB when a signal is received; Requesting to provide a predetermined authentication signal to the computer when the computer is offline with the main server; and receiving the availability of the remote control program from the main server when the predetermined authentication signal is not provided from the computer. Doing; And upon receiving a signal that the remote control program can be executed, proceed with at least one of the process of shutting down the affiliate server and the process of destroying the content file stored in the affiliate DB under the control of the main server, and execute the remote control program. And destroying the content file stored in the affiliated store DB upon receiving a signal that it cannot be received. 5. The method according to any one of claims 1, 2 and 4, wherein the main server or the merchant server sends at least one access warning message to the computer before executing the merchant server shutdown process or destroying the content file. Content protection method further comprising the step of. And a web server that stores content files and other files provided from the main server and the main server, and provides a connection between the control server and a plurality of merchant servers using a main DB and a wired / wireless communication network that provide the stored files to the main server. , The main server may include: a data receiver configured to receive the input data and provide the received data to a controller when predetermined data is input from the affiliated store server through the web server; A content extraction unit searching for a content file stored in the main DB and extracting the retrieved content file according to a command of a controller; A data transmitter for providing the extracted content file to the affiliated store server through the web server; A remote control unit for remotely controlling the affiliate server which transmits the signal when a signal indicating that there is a computer attempting to access the affiliate server is received from the affiliate server in a manner other than a predetermined method; And a control unit controlling functions of the content extraction unit, the remote control unit, the data receiving unit, and the data transmitting unit. When the authentication information of the member of the affiliated store is provided through the at least one affiliated server, the authentication information of the member of the affiliated store is compared with the member information stored in the main DB, and the state of each member of the affiliated store and the state of the affiliated server are controlled. Content protection system, characterized in that it further comprises a member management to provide. A web server that stores various files including content files provided from the merchant server and the merchant server, and provides a connection between the control server and the merchant server using a merchant DB and a wired / wireless communication network that provide the stored files and data to the merchant server. Including, The affiliated store server may include: a data receiving unit configured to receive the input file and provide the received file to a controller when a predetermined file is input from the main server through the web server; A content transmission unit providing the extracted content to the client computer; A content security unit configured to proceed with the termination process of the affiliate server under the control of the main server or to destroy the content file stored in the affiliate store DB under a predetermined condition; A content inlet / out unit for providing the decoded file to an affiliated store DB and extracting a file provided to an affiliated store DB; A data transmitter which provides various data to a main server through the web server; And a control unit controlling functions of a decoding unit, a content importing unit, a content transmitting unit, a content managing unit, a data receiving unit, and a data transmitting unit.

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