KR100999659B1 - System and terminal for playing content - Google Patents

Abstract

A content playback system for releasing and playing back DRM of content, comprising: a smart card; And a content playback terminal configured to release DRM of the DRM content by one of the card DRM agent or the terminal DRM agent based on whether the card DRM agent exists in the smart card, and to play the original content from which the DRM is released. A playback system is provided. According to the present invention, it is possible to solve the problem that the playback of the content to which the DRM technology is applied depends on the USIM, so that the DRM content can be played regardless of the type of the USIM.

Endpoint DRM Agent, Smart Card DRM Agent, DRM Release

Description

Content playback system and content playback terminal {System and terminal for playing content}

The present invention relates to a content reproducing system and a content reproducing terminal for reproducing DRM content. More specifically, the DRM release is performed by different subjects of DRM release according to whether a DRM agent exists in a smart card inserted into a terminal. The present invention relates to a content reproduction system and a content reproduction terminal for reproducing DRM content.

Recently, due to the development of communication network resources, wireless Internet services have been activated in mobile communication terminals such as mobile phones, and wireless Internet environments can be used anywhere on laptop terminals by connecting only high-speed wireless Internet transceivers such as Wibro (Wireless Broadband). Is being provided.

As such wireless Internet services are enabled in portable terminals, copyrights of contents consumed in portable terminals are emerging as a topic of industry. In other words, a solution to the problem of digital rights management (DRM) is required to be applied to a portable terminal.

Digital Right Management (DRM) technology prevents illegal distribution and copying of digital content, and manages digital content copyright by allowing only legitimate users to use the content within a given authority. DRM technology continuously protects content that is stored or streamed in real time using encryption technology, authentication technology, key management technology, packaging technology, rights expression technology, usage control technology, and tempering prevention technology.

Content packaged in DRM is restricted to be controlled only by devices that meet certain conditions (eg, manufacturer, product model, serial number, etc.) according to the content distributor's business policy.

However, as the WCDMA network, which is a third generation communication network, has recently been expanded, 11 subscriber information such as ESN (Electronic Serial Number) is stored in the USIM by applying Universal Subscriber Identity Module (USIM) technology, a kind of smart card, to the mobile communication terminal. Through mobile communication service is provided. USIM technology is also applied to transceivers that are connected to Wibro-enabled terminals or laptops.

However, due to the development of technology, not only the USIM which has the function of the original USIM, but also the USIM equipped with microprocessor and giga-class memory capable of logical operation is currently supplied to the market. That is, various USIMs are manufactured and supplied.

Consumers can receive basic mobile communication services, such as wireless Internet services, by simply inserting any type of registered USIM into the mobile communication terminal. However, unlike the mobile communication service, in the reproduction of the above-described DRM contents, various types of USIM cause confusion in the DRM technology operation of the mobile communication terminal.

That is, in the USIM having a memory and logic operation of several gigabytes, the DRM agent may be independently operated and activated by the terminal, but such a DRM agent does not exist in the commercial USIM.

Recently, the USIM, which has a DRM agent installed in the USIM and enables the user to play the DRM content by using a right object (RO) possessed by the USIM regardless of the terminal, is a USIM that does not have a DRM agent installed. Problems arise when this is used.

Even in the case of a mobile communication terminal compatible with the USIM, if there is no DRM agent in the mobile communication terminal, it is determined whether the DRM content can be played depending on what kind of USIM is inserted. That is, whether or not the DRM content can be played is dependent only on the USIM.

For this reason, even if the DRM agent is installed in the mobile communication terminal, there is no criterion on whether to use the DRM agent of the terminal or the USIM agent when the USIM having the DRM agent is inserted or replaced independently.

For this reason, there has been a problem in that the terminal plays content, such as a collision between DRM agents or an inability to play DRM content.

An object of the present invention is to provide a content reproducing system and a content reproducing terminal for reproducing DRM content by releasing a DRM according to whether a DRM agent exists in a smart card inserted in a terminal.

Other objects of the present invention will become more apparent through the preferred embodiments described below.

According to an aspect of the present invention for achieving the above object, there is provided a content reproduction system.

According to an embodiment of the present invention, a content playback system for releasing and playing back DRM of content, comprising: a smart card; And a content playback terminal configured to release DRM of the DRM content by one of the card DRM agent or the terminal DRM agent based on whether a card DRM agent exists in the smart card and to play the original content of which the DRM is released. A content reproduction system is provided.

According to another aspect of the present invention for achieving the above object, there is provided a content playback terminal.

According to an embodiment of the present invention, a content playback terminal connected to the smart card, the terminal DRM agent for releasing the DRM of the Digital Right Management (DRM) content; A DRM agent determining unit which determines whether a card DRM agent exists in the smart card and transmits a DRM release request of the DRM content to the card DRM agent or the terminal DRM agent according to the determination result; A content reproducing unit for acquiring and reproducing the original content whose DRM is released; And a smart card connection unit performing data communication with the smart card.

According to another aspect of the present invention for achieving the above object, there is provided a content playback method.

According to an embodiment of the present invention, in the content playback method of a content playback terminal connected to a smart card and including a terminal digital rights management (DRM) agent, determining whether a card DRM agent exists in the smart card. ; Transmitting a DRM release request of the DRM content to the smart card DRM agent or the terminal DRM agent based on whether the card DRM agent exists in the smart card; And playing the original content of which the DRM is released by the card DRM agent or the terminal DRM agent.

As described above, according to the present invention, in the transitional situation in which a smart card capable of installing or installing a DRM agent is disseminated, it is possible to solve the problem that the reproducibility of the content to which the DRM technology is applied depends on the smart card. Regardless of the type of card, DRM content can be played back.

As the invention allows for various changes and numerous embodiments, particular embodiments will be illustrated in the drawings and described in detail in the written description. However, this is not intended to limit the present invention to specific embodiments, it should be understood to include all modifications, equivalents, and substitutes included in the spirit and scope of the present invention.

Terms including ordinal numbers such as first and second may be used to describe various components, but the components are not limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as the second component, and similarly, the second component may also be referred to as the first component. And / or < / RTI > includes any combination of a plurality of related listed items or any of a plurality of related listed items.

When a component is referred to as being "connected" or "connected" to another component, it may be directly connected to or connected to that other component, but it may be understood that other components may be present in between. Should be. On the other hand, when a component is said to be "directly connected" or "directly connected" to another component, it should be understood that no other component exists in the middle.

The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting of the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this application, the terms "comprise" or "have" are intended to indicate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, and one or more other features. It is to be understood that the present invention does not exclude the possibility of the presence or the addition of numbers, steps, operations, components, components, or a combination thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art. Terms such as those defined in the commonly used dictionaries should be construed as having meanings consistent with the meanings in the context of the related art and shall not be construed in ideal or excessively formal meanings unless expressly defined in this application. Do not.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings, and in describing the present invention with reference to the accompanying drawings, the same or corresponding components are given the same reference numerals regardless of the reference numerals. Duplicate explanations will be omitted.

1 is a view showing the components of the content playback system according to an embodiment of the present invention.

Referring to FIG. 1, the content reproducing system of the present invention includes a content reproducing terminal and a smart card connected to the content reproducing terminal. Hereinafter, each component will be described in detail.

The content playback terminal 100 includes a content playback unit 110, a DRM agent determination unit 120, a DRM agent-T 130, a memory-T 140, and a smart card connection unit 150. The content playback terminal 100 is connected to the smart card 160 including the memory-S 170, the DRM agent-S 180, and the terminal connection unit 190. The identifier "-T" means "Terminal" and "-S" is used as an abbreviation for "Smart Card".

The content reproducing terminal 100 may include a mobile communication terminal, a PDA, a notebook computer, and includes all other communication terminals capable of transmitting and receiving data by connecting to a smart card having an internal arithmetic function and a memory. However, it is assumed that the terminal is a mobile communication terminal.

Although not shown in the drawing, the content reproducing terminal 100 may further include an input / output unit such as a speaker, a microphone, a key button, and a wireless communication unit such as a wireless signal transmitting antenna, a duplexer, a power amplifier, an internal oscillator, and a filter circuit. .

1 illustrates a case where the smart card 160 is a USIM card, but the smart card may be a Universal Integrated Chip Card (UICC), a Universal Subscriber Identity Module (USIM), a Subscriber Identity Module (SIM), or a R-SIM (Removable). Subscriber Identity Module) may be named in various terms, but it is apparent that the smart card to which the terminal of the present invention is not limited thereto.

In FIG. 1, the smart card 160 and the content playback terminal 100 are separately shown, but the smart card 160 is manufactured to be detachably mounted on the content playback terminal 100, and the smart card 160 is mounted on the content playback terminal 100. A connection portion for accommodating the 160 and transmitting and receiving an electrical signal with the smart card 160 is formed.

The memory-S 170 of the smart card 160 basically includes subscriber identification information IMSI (International Mobile Station Identity) and MSISDN (Mobile Station Integrated System Digital Network). Based on this, the content playback terminal 100 is Call processing can be performed. In this case, the content playback terminal 100 may be a mobile communication terminal or a laptop to which a modem into which the smart card 160 is inserted is connected. Such subscriber information can be set and changed using an Over-The-Air Activation (OTA) procedure.

The smart card 160 may exchange data with the content playback terminal 100 through a preset interface between the card and the terminal. That is, the smart card connection unit 150 of the terminal and the terminal connection unit 190 of the smart card 160 may exchange information processed or stored in each by a preset protocol.

The content player 110, the DRM agent determiner 120, and the DRM agent-T 130 illustrated in FIG. 1 may be a program implemented on a separate microprocessor, and a program in which one microprocessor is time-divisionally operated. It may be.

The content player 110 is a logical function unit operated by a microprocessor as a program capable of playing various types of multimedia content such as a video player, a voice player, and a text viewer.

Accordingly, the content reproducing unit 110 may reproduce the corresponding content by interpreting the selection input of the content and the start input of the content playback through the key button included in the terminal.

However, the DRM content (Digital Right Management Content) can not be played directly by the content playback unit 110. That is, the DRM content refers to content that is encrypted or packaged so that only a user who has a right to use can be used according to the digital copyright policy of the content provider.

Therefore, for example, in the case of DRM contents encrypted and packaged together with a key, the DRM should be released through a separate middleware DRM agent 130 or 180.

That is, the DRM agent 130 or 180, which is a middleware, is required because the original content can be obtained by decrypting the encrypted DRM content only by the authorized usage right. The original content may be in an encoded format (eg, MPEG-2, AVI, WMV, etc.) by a standard without permission, and the content player 110, which is a player, may play it.

In this case, the content playback unit 110 of the present invention requests the DRM agent determination unit 120 to release the DRM of the corresponding DRM content. The release of the DRM refers to a process of decrypting the encrypted DRM content using a right object (RO) of the DRM content. In this case, the usage right may be a key for decrypting the DRM content.

In addition, the release of the DRM may mean a process of unpacking the packaged DRM content and decrypting the DRM content using a key in the package. However, the release of the above-described DRM may be changed by the digital rights management policy of the content provider who distributes the DRM content, but is not limited thereto.

The DRM agent determination unit 120 included in the content playback terminal 100 according to an embodiment of the present invention may include the DRM agent-T 130 of the content playback terminal 100 and the DRM agent-S of the smart card 160. In step 170, the DRM agent determines whether to release the DRM.

The DRM agent determiner 120 determines whether the DRM agent-S 180 exists in the smart card 160. The DRM agent determining unit 120 may access the memory-S 180 of the smart card 160 and search for the DRM agent driving program to determine whether the DRM agent-S 180 exists according to the search result. have.

When the DRM agent determining unit 120 determines that the DRM agent-S 180 exists in the smart card 160, the DRM agent determining unit 120 releases the DRM of the corresponding content by the DRM agent-S 180. request.

Accordingly, the DRM agent-S 180 decrypts the DRM content by using a right (for example, using a key). When the content to be decrypted is stored in the memory-S 170, the DRM agent-S 180 directly reads out the DRM content from the memory-S 180 and releases the DRM.

However, when the DRM content is stored in the memory-T 140, the DRM content may be read from the memory-T 130 through the terminal connection unit 190 and the smart card connection unit 150 to release the DRM. However, the DRM content read from the memory-T may be previously included in the DRM release request transmitted by the DRM agent determiner 120 of the content playback terminal 100 according to another embodiment of the present invention to the DRM agent-S. .

The DRM agent-S 130 transmits the original content decrypted with the use right to the content playback unit 100 through the terminal connection unit 190 and the smart card connection unit 150.

The content reproducing unit 100 may reproduce the original content from which the DRM is released and output video or audio data through a display unit (not shown) and a speaker (not shown) of the content reproducing terminal 100.

As described above, according to the content playback terminal 100 according to an embodiment of the present invention, even though the DRM agent-T 130 exists independently of the content playback terminal 100, the DRM of the smart card 160 may be used. The DRM may be released using the agent-S 180.

That is, according to the present invention, since the DRM agent-S 180 of the smart card 160 is set to have a high priority, the DRM agent-S 180 of the smart card 160 is easy to replace and inserted into various content playback terminals as compared to the content playback terminal 100 which is not easy to replace. In this case, a DRM agent-S 180 having a high probability of having various contents or usage rights may be used.

For example, when a USIM without DRM agent-S 180 is purchased, the content playback terminal of the present invention uses the DRM agent-T 130 of the terminal, as will be described later with reference to FIG. 2. DRM content can be played back. In addition, even after the user has replaced the smart card 160 in which the DRM agent-S 180 exists, the DRM agent of the smart card 160 according to the content playback terminal 100 of the present invention described with reference to FIG. -S 180 is used to play the DRM content.

2 is a view showing the components of the content playback system according to an embodiment of the present invention.

Referring to FIG. 2, the configuration of the content playback terminal 100 is the same as that shown in FIG. 2. However, the internal configuration of the smart card 160 bound to the terminal is different.

In the smart card 260 of FIG. 2, the DRM agent-S 180 included in the smart card 160 of FIG. 1 does not exist.

That is, not all smart cards include a microprocessor, and the smart card may include only information of a mobile communication service subscriber or only other additional service information or authority information. In addition, even when a microprocessor is included in the smart card, not all the driving programs of the DRM agent are installed.

When such a smart card is connected to the content reproducing terminal 100, as described above with reference to FIG. 1, the smart card cannot release the DRM of the DRM content.

However, even in this case, the content playback terminal 100 of the present invention calls the content playback unit 110 by receiving DRM content from the user and receiving a playback input.

The content playback unit 110 transmits a DRM release request to the DRM agent determination unit 110, and accordingly, the DRM agent determination unit 120 determines whether the DRM agent-S exists in the smart card 260. However, as shown in FIG. 2, since the DRM agent-S does not exist, the DRM agent determination unit 120 transmits a DRM release request to the DRM agent-T 130.

Determination of whether DRM Agent-S exists can be performed by various approaches. For example, the DRM agent determination unit 120 may call an operating system or a system manager of the smart card 260 to determine whether the DRM agent program is installed. In the case of a Windows-based operating system (OS), it is possible to determine whether to install a DRM program by using a registry search method. For example, if a DRM agent is installed on a smart card, the code value or program identifier or character of the DRM agent program is registered in the registry, and the driving history of the DRM agent is stored. Therefore, the DRM agent-S is read to determine whether the DRM agent-S exists. can do. However, if the character string or program identifier does not exist, the DRM agent determination unit 110 determines that the DRM agent-S does not exist.

In addition, in the case of a Linux-based OS, it may be determined whether the DRM agent is installed by a RPM (Redhat Package Manager) method. In other words, RPM collects and installs several files that are installed while already compiled and manages them as one file. In this case, when the DRM agent determination unit 120 of the terminal transmits a query to the RPM, it transmits a response indicating that some file is installed in a certain package and thus may determine whether the DRM agent is installed. Therefore, the DRM agent determining unit 110 may determine whether the DRM agent-S exists according to the response of the RPM.

However, the above-described example is merely an example of an approach used by the DRM agent determination unit of the present invention, and it is obvious that it may be determined by querying various DBMSs that may be installed in the smart card. In addition, when the system manager, OS or DBMS of the content playback terminal is set in advance to manage data and applications of the smart card connected to the content playback terminal, the presence of the DRM agent-S of the smart card may be determined.

In this case (when the DRM agent-S 170 does not exist), the DRM agent determination unit 120 reads out the corresponding DRM contents from the memory-S 170 or the memory-T 140, and the DRM release request together with the DRM release request. May transmit to Agent-T 130.

However, the DRM agent determination unit 120 included in another embodiment of the present invention transmits only the DRM release request of the corresponding DRM content to the DRM agent-T 130, and the DRM agent-T 130 transmits the corresponding DRM content. The DRM may be set to be directly read from the memory-S 170 or the memory-T 140 to release the DRM.

However, since the DRM agent-T 130 requires a usage right to release the DRM of the DRM content, the DRM agent-T 130 may release the DRM by reading the usage right from the memory-S 170 or the memory-T 140.

The DRM agent-T 130 transmits the decrypted original content to the content reproducing unit 100 so that the content reproducing unit 100 can output the content through the display unit and the speaker.

Therefore, as described above with reference to FIGS. 1 and 2, according to the content reproducing terminal 100 of the present invention, the DRM content may be reproduced regardless of whether the DRM agent-S exists in the smart card 160.

3 is a flowchart of a program for implementing a method of playing content according to an embodiment of the present invention.

3, the content playback terminal 100 of the present invention receives the DRM content selection and playback input from the user to generate a DRM content playback unit call signal (S300).

The DRM content playback unit 110 searches for DRM content (S310). However, since the retrieved DRM content cannot be encrypted and played back, the DRM release by the middleware DRM agent must be performed first.

Therefore, according to the DRM content playback method of the present invention, the DRM agent determination unit 120 of the content playback terminal 100 determines whether the DRM agent-S exists in the smart card 160 or 260 (S320). That is, the DRM agent determining unit 120 may access the memory-S 170 of the smart card 160 or 260 to determine whether the DRM agent driving program exists.

In this case, whether the DRM agent-S exists in the smart card 160 or 260 may be determined by the DRM agent determining unit 120 inquiring about the OS registry of the smart card 160 or 260 or querying the RPM.

If the DRM agent-S 180 exists in the smart card 260, the DRM release request is transmitted to the DRM agent-S 180 (S330). That is, this case corresponds to the case where the smart card 260 of FIG. 1 is attached to the content playback terminal 100.

However, if the DRM agent does not exist in the smart card 260, the DRM release is impossible through the USIM, so the DRM agent determination unit 120 transmits the DRM release request to the DRM agent of the content playback terminal (S340). That is, this case corresponds to the case where the smart card 260 of FIG. 2 is attached to the content playback terminal 100, unlike step S330.

Thereafter, the process proceeds to step S350, and the DRM agent-S 180 of the smart card 160 or the DRM agent-T 130 of the content playback terminal 100 releases the DRM of the DRM content (S350).

In other words, the DRM agent 130 or 180 decrypts the encrypted DRM content using the usage right and returns the original content to be reproduced by the content reproducing unit. Alternatively, the DRM packaged DRM content may be unpackaged to decrypt the DRM content with a key inserted in the package.

However, the aspect of the release of the DRM is not limited thereto, and the DRM release of another aspect may be required according to the business policy of the DRM content service provider. For example, the DRM agent 130 or 180 may access a server of a DRM content provider, or may access a right issuer (RI) server to transmit a use right to a use right authentication server. Accordingly, the authorization server verifies whether the authorization is a legitimate authority (for example, whether it is within an expiration date) and authenticates the authorization.

If the use right is authenticated, the use right authentication server may transmit the authentication result to the content providing server, and the content providing server may transmit the original content to the content reproducing terminal 100.

In this case, the original content may be stored in the memory-S (depending on whether the permission is transmitted from the DRM agent-S 180 of the smart card 160 or from the DRM agent-S 130 of the content playback terminal 100). 170 or memory-T 140.

When the content playback unit 110 obtains the original content through the process of releasing the DRM of the various aspects described above, the content playback unit 110 reproduces the original content and outputs the original content through the display unit or the speaker ( S360).

Therefore, according to the DRM content playback method of the present invention, regardless of whether or not the DRM agent is present in the USIM card bound to the content playback terminal, the DRM content can be released and the original content can be played back.

It is apparent that the method described with reference to FIG. 3 can be equally applied to not only downloaded content but also content that is transmitted and reproduced by a preset data transmission unit in real time.

4 is a flowchart of a program for implementing a content playback method according to another embodiment of the present invention.

Referring to FIG. 4, although the DRM agent-S 180 existing in the smart card 160 exists, the DRM agent-S 180 performs DRM release even though the content reproduction method described in FIG. 3 exists. If you do not do this is different.

That is, in step S400, when the content playback terminal 100 determines that the DRM agent-S 180 exists in the smart card 160, the content playback terminal 100 sends a DRM release request to the DRM agent-S 180 of the smart card 160. The same is the same (S410).

However, in step S420, a case where the DRM release disable signal is received from the DRM agent-S 180 of the smart card 160 may occur. That is, in this case, it means that the smart card 160 cannot perform DRM release due to various causes such as a malfunction of hardware of the smart card 160 or an error in executing the DRM agent program.

In this case, the DRM agent determination unit 120 transmits a DRM release request to the DRM agent-T 130 (S430).

Therefore, in this case, the DRM is released by the DRM agent installed in the content reproduction terminal (S440), and the original content is reproduced by the content reproduction unit (S450).

According to the DRM content playback method according to another embodiment of the present invention, even if the DRM agent-S 180 exists in the smart card 160, if the DRM release cannot be performed, the DRM of the content playback terminal 100 By using the Agent-T 130, the DRM content can be played back.

Therefore, according to the DRM content playback method of the present invention, the USIM dependency of DRM content playback can be completely eliminated.

The method of the present invention as described above may be implemented as a program and stored in a computer-readable recording medium (CD-ROM, RAM, ROM, floppy disk, hard disk, magneto-optical disk, etc.).

Although the above has been described with reference to the embodiments of the present invention, those skilled in the art may variously modify and modify the present invention without departing from the spirit and scope of the present invention as set forth in the claims below. It will be appreciated that it can be changed.

1 is a diagram showing the components of a content reproduction system according to an embodiment of the present invention.

2 is a diagram showing the components of a content reproduction system according to an embodiment of the present invention.

3 is a flowchart of a program for implementing a method of playing content according to an embodiment of the present invention.

4 is a flowchart of a program for implementing a content playback method according to another embodiment of the present invention.

Claims (17)

In a content playback system that releases and plays back digital rights management (DRM) of content, Smart card; And If there is a card DRM agent in the smart card, the card DRM agent to release the DRM content of the DRM content, and includes a content playback terminal for playing the original content released the DRM, The content reproduction terminal releases the DRM of the DRM content by the terminal DRM agent when the card DRM agent does not exist in the smart card, the content reproduction system characterized in that to play the original content released the DRM. The method of claim 1, The content playback terminal comprises a DRM agent determination unit for determining whether the card DRM agent exists in the smart card. The method of claim 2, And the DRM agent determining unit determines whether the card DRM agent exists by searching or querying the system manager for managing data stored in the smart card. delete The method of claim 3, The content playback terminal includes a content playback unit for playing the original content, And the card DRM agent transmits the original content of which the DRM is released to the content reproducing unit, so that the content reproducing unit reproduces the original content. delete In the content playback terminal connected to the smart card, A terminal DRM agent for releasing DRM of digital right management (DRM) content; When a card DRM agent is present in the smart card, a DRM release request of the DRM content is transmitted to the card DRM agent, and when a card DRM agent is not present in the smart card, the DRM release request of the DRM content is notified. A DRM agent determination unit transmitting to the terminal DRM agent; A content reproducing unit configured to acquire and reproduce original content released by the DRM by the card DRM agent or the terminal DRM agent; And Content playback terminal comprising a smart card connection for performing data communication with the smart card. delete delete A content playback method of a content playback terminal connected to a smart card and including a terminal DRM (Digital Right Management) agent, Determining whether a card DRM agent exists in the smart card; When the card DRM agent exists in the smart card, transmitting a DRM release request of the DRM content to the smart card DRM agent; If the card DRM agent does not exist in the smart card, transmitting a DRM release request of the DRM content to the terminal DRM agent; And Playing the original content whose DRM is released by the card DRM agent or the terminal DRM agent. delete delete The method of claim 10, After transmitting the release request, Receiving the inoperable signal of the DRM release request from the card DRM agent, and transmitting the release request of the DRM to the terminal DRM agent. The method of claim 10, The smart card DRM agent or the terminal DRM agent decrypts the DRM content by using a right to use the DRM release request. The method of claim 10, How to play DRM content Transmitting a usage right held by the smart card DRM agent or the terminal DRM agent to a usage right authentication server by the DRM release request; And And receiving the original content from a content server providing the DRM content, based on the usage right authentication of the usage right authentication server. The method of claim 15, In the step of transmitting the permission to the authorization server The smart card DRM agent is sent to the DRM release request, How to play content And storing the original content in the smart card. The method of claim 15, In the step of transmitting the permission to the authorization server The smart card DRM agent is sent to the DRM release request, How to play content And storing the original content in the content playback terminal.

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