KR20020076470A - Security service method for digital contents distributions through online and one-time recordable media, security service system therefor, and one-time recordable media thereof - Google Patents

Abstract

PURPOSE: A security service system and method are provided to decrease a risk of an illegal copy or a hacking by introducing a disposable recording medium as an off-line distributing method of digital contents and additionally applying a public key encryption mechanism to a contents key itself being used for setting a security of digital contents in an on-line distribution of digital contents. CONSTITUTION: A client connects to a contents server through the Internet and requests a contents purchase(410). The contents server codes purchase-requested digital contents by the client into a predetermined contents key, and the contents key is coded into a user public key of the corresponding client(420). The contents server combines the contents coded into the contents key with the contents key coded into the user public key and transmits combined contents(430). The client decodes the contents key coded into the user public key into a user private key(440), decodes the coded contents into a decoded contents key, and reproduces the decoded contents key(450). The contents key is transmitted to a DCD(Digital Convergence Disc) medium as a decoded format and content of the contents is transmitted to a DCD medium as a format coded by a contents key through a communication channel such as a USB(Universal Serial Bus) in a digital contents on an on-line(460). The coded contents are recorded in a data area, and the coded contents are recorded in a security area(470).

Description

Security service method for digital contents distributions through online and one-time recordable media, security service system therefor, and one -time recordable media

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a security mechanism applied to digital content, and more particularly, to a security service method and system for the distribution of digital content through an online one-time recording medium and online.

Various digital contents, such as music contents such as MP-3 format and video contents such as MPEG format, may be illegally copied.

In the conventional distribution method of digital content, the digital content is downloaded online and a password is paid when the price is paid, so that only the purchased user can use the digital content. In addition, the digital content purchased online can be recorded on a smart card (flash ROM system) or the like and used / played off-line through a separate player (MP-3 player, etc.).

However, the above method has a problem that other users who illegally copy the password provided with the digital content can use the digital content without any limitation.

In addition, the distribution method of the conventional digital content mainly depends on the online, but as the MP-3 player and the like is generalized, the necessity of distributing the digital content offline like the existing music CD is increasing. However, in the offline distribution method of digital content, unlike a conventional music CD, a security mechanism should be applied to an offline medium on which digital content is recorded.

The technical problem to be achieved by the present invention is to solve the above problems, to introduce a one-time recording medium as one of the offline distribution of digital content, the content key itself used for the security setting of digital content in the online distribution of digital content By additionally applying the public key encryption mechanism to the network, digitally through online and one-time recording media that can greatly reduce the risk of illegal copying or hacking, and to interconnect the security mechanisms applied to the one-time recording media online and offline. The present invention provides a security service system and method in content distribution.

Another technical problem to be achieved by the present invention is to provide a one-time recording medium used for distributing secured digital content offline.

1 schematically illustrates the structure of a one-time recording medium and the configuration of online digital contents according to an embodiment of the present invention.

2 schematically illustrates an overall system configuration for a security service according to an embodiment of the present invention.

3 is a flowchart illustrating a security key generation and distribution process according to an embodiment of the present invention.

4 is a flowchart illustrating a security service method in digital content distribution through online and one-time recording media according to an embodiment of the present invention.

5 and 6 are flowcharts of a security service method in digital content distribution through online and one-time recording media according to another embodiment of the present invention.

7 is a flowchart illustrating a security service method in digital content distribution through online and one-time recording media according to another embodiment of the present invention.

In order to solve the above technical problem, the security service method in the digital content distribution through the online and one-time recording medium according to an aspect of the present invention,

In the security service method for distributing encrypted digital content,

(a) generating a pair of a user public key and a user private key having a mapping relationship to each other, and providing the public key and the user private key to a client through a communication network;

(b) receiving an online service request from the client for a content key required to decrypt specific digital content recorded on a one-time recording medium;

(c) encrypting the content key requested in step (b) using the user public key generated in step (a) as an encryption key; And

(d) providing the client with the content key encrypted in step (c) through a communication network;

The encrypted content key in the client is decrypted using the user private key provided in step (a) as a decryption key, and then the specific digital content recorded in the one-time recording medium is decrypted using the decrypted content key. It features.

Preferably, the specific digital content is read from the one-time recording medium and combined with the encrypted content key provided in step (d), and then recorded in the storage space in the client.

In addition, it is preferable that the encrypted content key provided in step (d) is decrypted using the user private key provided in step (a) as a decryption key and then recorded in the one-time recording medium.

Preferably, the decrypted content key is recorded in an area physically separated from an area in which the specific digital content is recorded in the one-time recording medium.

According to another aspect of the present invention, a security service method in digital content distribution through online and one-time recording media,

In the security service method for distributing encrypted digital content,

(a) generating a pair of a user public key and a user private key having a mapping relationship with each other, and providing the user public key and the user private key to a client through a communication network;

(b) receiving a request for purchase of specific digital content from the client;

(c) encrypting the digital content requested in step (b) using a predetermined content key;

(d) encrypting the content key used in the encryption process in step (c) using the public key generated in step (a) as an encryption key; And

(e) providing the digital content encrypted in step (c) and the content key encrypted in step (d) to the client through a communication network,

In the client, the encrypted content key provided in step (e) is decrypted using the user private key provided in step (a) as a decryption key, and then the decrypted content key and encrypted digital provided in step (e). And the content is recorded on the one-time recording medium.

In order to solve the other technical problem, the security service system according to an aspect of the present invention,

A security service system for distributing encrypted digital content,

A security server generating a pair of user public key and user private key having a mapping relationship with each other, and providing the user private key to each client through a communication network; And

Upon receiving an online service request for a content key required to decrypt specific digital content recorded on a one-time recording medium, encrypting the content key using the user public key of the client as an encryption key, and encrypting the encrypted content key. It includes a content server provided to the client through,

The encrypted content key in the client is decrypted using the private key of the client as a decryption key, and then the specific digital content recorded in the one-time recording medium is decrypted using the decrypted content key.

In addition, the user public key used to encrypt the content key in the content server is preferably provided by the security server.

Security service system according to another aspect of the present invention,

A security service system for distributing encrypted digital content,

A security server generating a pair of user public key and user private key having a mapping relationship with each other, and providing the user private key to each client through a communication network; And

Receiving a request for purchasing specific digital content from a client, encrypting the requested digital content using a predetermined content key, encrypting the predetermined content key using a user public key of the client as an encryption key, and encrypting the encrypted content. A content server for providing the digital content and the encrypted content key to the client through a communication network;

The encrypted content key in the client is decrypted using the user private key of the client as a decryption key, and then the decrypted content key and the encrypted digital content are recorded in a one-time recording medium.

In order to solve the another technical problem, the one-time recording medium according to one aspect of the present invention,

A data area in which digital content encrypted with a predetermined content key is recorded; And

A security area in which the predetermined content key is recorded;

Data can be recorded only once in the empty space on the data area,

The data area and the security area are physically separated from each other,

The encrypted digital content recorded in the data area is decrypted using the content key recorded in the secure area.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the configuration and operation of the present invention. FIG. 1 schematically shows the structure 100 of a digitally integrated disc, which is a one-time recording medium according to an embodiment of the present invention, and the configuration 150 of digital content on-line.

The present invention proposes a distribution model of digital contents through an offline one-time recording medium as a way to promote the distribution of digital contents. In the following, the one-time recording medium 100 used in the present invention is referred to as a Digital Convergence Disc (DCD). Here, the one-time means that recording can be performed only once in the empty space of the DCD 100.

Encryption and decryption using a content key are applied to digital content recorded in the DCD 100, as in the case of online. As shown in FIG. 1, the DCD 100 physically separates an area 102 in which digital content secured (encrypted) using a content key and an area 104 in which the content key itself is recorded. Therefore, only the DCD engine is restricted from accessing the content key. Therefore, the digital content is encrypted and recorded with the content key on the DCD 100, and the content key is distributed (purchase / sale, etc.) off-line in a protected state in a physical manner. In addition, as described below, the DCD 100 may not only be distributed in the state where both the digital content and the content key are recorded, but may also be distributed in the state where only the digital content is recorded. In this case, the content key is acquired / purchased online. In addition, when the DCD 100 medium is distributed as a blank disc, both the digital content and the content key may be acquired / purchased online and recorded in the DCD 100.

In addition, the present invention proposes a method for greatly reducing the risk of illegal copying or hacking by further strengthening a security mechanism set for online digital contents. The overall configuration 150 of digital content online according to the present invention is divided into a digital content 156 encrypted with a content key and a header 154 in which various control information thereof is recorded. The header 154 includes a DRM information field ( Not shown), the content key field 152, and the like. Here, as shown in FIG. 1, the header 154 is encrypted in a public key manner. Therefore, online content is encrypted with a content key, the content key is encrypted again with a user's public key, and then distributed in a form in which the encrypted digital content portion and the encrypted content key portion are combined (purchase / sale / superdistribution, etc.). do.

In FIG. 1, the entire header 154 is encrypted using a public key method. However, depending on the application, only the content key field 152 used for encrypting the content 156 among the headers 154 may be disclosed. It may be encrypted in a key way. Here, the public key encryption method refers to a method of dividing a security key into two, using an encryption key and a decryption key. The encryption key is registered and published in the public list, and the decryption key is kept private by the individual. Therefore, the encryption key is called a user public key and the decryption key is called a user private key or a secret key. A person (B) who wants to communicate secretly to the subscriber (A) encrypts the plaintext to be sent to the user's public key disclosed by A and sends the ciphertext to A, and A decrypts the ciphertext with the secret key that he secretly kept. Can be. That is, the ciphertext encrypted through the public key is decrypted into the plain text through the user private key or the secret key.

In addition, the present invention provides a variety of ways to enable the distribution of digital content through an online server and offline media by interconnecting the security mechanism in the DCD (100) on-line and the security mechanism for the digital content (150) on-line. present. Specifically, a method of distributing secured content and a content key through online (recording on an offline DCD medium) (hereinafter referred to as the first embodiment), distributing a content key through online and using the content key through an offline DCD medium. A method of distributing secured content (Second Embodiment) and a method of distributing secured content and a content key (reconstructed into a security mechanism for digital content online) through a DCD medium in an offline state (hereinafter referred to as a third embodiment) Ex) and the like.

First, a system configuration according to the present invention will be described first. 2 schematically illustrates an overall system configuration for a security service according to an embodiment of the present invention. As shown in FIG. 2, the overall system configuration according to the present invention includes a security content providing system 200 and a client system 250 interconnected through the Internet.

The secure content providing system 200 includes a security server 210 that generates and manages a security key of a user public key and a user private key, and a content server 220 that performs an online distribution function of secured content. Here, the security server 210 and the content server 220 may operate in separate computer systems, and may operate for each functional block in one computer system having ordinary skill in the art. He will understand.

The security server 210 generates a pair of a user public key and a user private key having a mapping relationship with each other, and manages them for each client. Here, the user private key is provided to each client and the user public key is provided to the content server 220. In addition to the user public key and user private key, the security key includes a certificate key, a super distribution key, or a client identification code. Hereinafter, the user public key and the user private key directly related to the present invention. The description centers on.

The content server 220 provides various types of online services for the secured content to the client computer 260, and there is a slight difference in operation methods for each embodiment of the present invention. The example is explained together.

The client system 250 reads / writes data from the DCD medium 280 and the DCD medium used in the offline distribution process of the digital content in the present invention, centering on the client computer 260, and a universal serial bus (USB). And a DCD controller 270 for mediating data transmission with the client computer 260 via a communication channel, such as a computer. Each embodiment of the present invention also differs slightly in the manner of operation of the client system 250, which will be described together in each method embodiment of the present invention.

DCD controller 270 includes an engine portion for reading / writing data from DCD medium 280, typically a DCD driver attached to client computer 260 in the form of an external driver (eg, CD-ROM). Similar to a driver). In addition, the DCD controller 270 may be a H / W player that drives digital content on the DCD medium 280 itself without performing an interface with the client computer 260 (eg, similar to an MP3 player). . Also, it may be a DCD record that provides a function of receiving an analog input from the outside and converting the same into digital data and recording the same on the DCD medium 280. In addition, the concept broadly includes a S / W driver that performs the function of playing the digital content to which the security mechanism according to the present invention is applied in the client computer (260).

Of course, the digital content distributed through the online with security set according to an embodiment of the present invention can be played directly on the client computer 260. In addition, the digital content distributed through the offline DCD medium 28 with the security set in accordance with an embodiment of the present invention can also be directly played offline in the DCD controller 270 such as a DCD player or a DCD record. Do. Hereinafter, a description will be given of a method of interconnecting security mechanisms online and offline, and specific security mechanisms used in the online and offline DCD media 280 will be described together in each method embodiment of the present invention.

Subsequently, an operation method of each method embodiment of the present invention will be described. First, the method of generating and distributing a security key, which is a prerequisite for distributing digital contents online, will be described first in each method embodiment. 3 is a flowchart illustrating a security key generation and distribution process according to an embodiment of the present invention.

First, a client accesses a content server through the Internet and performs user registration (step 310). The content server then sends a security key management module to the client for operating the security mechanism set in the digital content according to an embodiment of the invention (step 320), which is installed on the client (step 330).

Next, the security key management module is driven to access the security server (step 340). In step 340, the security key management module provides identifier information of the client and requests creation of the security key.

Then, the security server generates a pair of user public key and user private key to be used in the public key encryption scheme for the client (step 350). In addition to the user public key and the user private key, a verification key for verifying the user public key and the user private key, and a superdistribution key to be used as a security key in the superdistribution process are also generated in step 350.

The security server generates security keys and stores them in a database, and transmits a user public key to a content server, and a user public key and a user private key to a client (steps 360a and 360b). The content server stores and manages the user public key of each client in a separate database, and the user private key of the client is stored and managed through the security key management module. However, for efficient operation of the security mechanism, the security server provides the content server and the client with a set of security keys such as a user public key, a user private key, a verification key, and a super-distribution key, respectively. It would be desirable to use them properly. However, the user's private key must be transmitted.

Subsequently, a first embodiment in which secured digital content and a security key are distributed online is described. 4 is a flowchart illustrating a security service method in digital content distribution through online and one-time recording media according to the first embodiment of the present invention.

First, the client accesses the content server through the Internet and makes a content purchase request (step 470). Of course, the content purchase request in step 470 includes a payment process.

Then, the content server encrypts the digital content requested by the client with a predetermined content key, and the content key is encrypted with the user public key of the client (step 420). That is, since the user public key of the client is used in step 420, it is natural that the security key generation and distribution process shown in FIG. 3 should be preceded before step 420. In this case, the user public key is provided to the content server by the security server, as described above.

Next, the content server combines the content encrypted with the content key and the content key encrypted with the public key of the client and transmits it to the client (step 430). That is, the overall configuration of the digital content online according to the embodiment of the present invention is as described with reference to FIG.

First, the client decrypts the content key encrypted with the user public key with the user private key (step 440), and decrypts and reproduces the encrypted content with the decrypted content key (step 450). In addition, the digital content in the client is stored and managed in the form shown in FIG. 1B, and the digital content may be reproduced by performing steps 440 and 450 by a separate software driver. The digital content purchased through the online may go through a super distribution process. In this case, the content key encrypted with the user's public key is decrypted with the user's private key, then encrypted and propagated again with the super-distribution key, and the super-distribution key is provided when the propagated client pays for the propagated digital content.

Next, a description will be given of the process in which online digital content is recorded on the DCD medium. In the first embodiment it is assumed that the DCD medium is in the form of a blank disc. First, in a digital content online, the content key is decrypted and the content is encrypted with the content key and transmitted to the DCD medium through a communication channel such as USB (step 460). As described above, the encrypted content in the DCD medium is recorded in the data area, the decrypted content key is physically separated from the data area, and is physically protected in the secure area that only the DCD engine can access. 470). Although not shown in FIG. 4, it is obvious that a DCD driver equipped with a DCD engine should exist between the client computer and the DCD medium.

In addition, input of analog or digital data through a DCD recorder may be performed on the DCD medium in the form of a blank disk. In this case, a predetermined content key generation mechanism should be provided together.

If the digital content is recorded in the DCD medium in step 470, it can be played back through a separate H / W driver. In this case, the H / W driver reads the content key from the security area and decrypts and reproduces the encrypted digital content recorded in the data area using the content key.

Subsequently, a second embodiment in which secured digital content is distributed through an offline DCD medium and a content key is provided via online will be described. 5 and 6 are flowcharts of a security service method in digital content distribution through online and one-time recording media according to a second embodiment of the present invention.

First, referring to FIG. 5, a DCD medium recorded only in encrypted data in a data area is purchased through offline (step 510). Since the content key necessary for decrypting the encrypted content is not included in the DCD medium, the digital content cannot be reproduced as it is. In the second embodiment, the content key is obtained (purchased) online.

Referring to FIG. 6, a client accesses a content server through the Internet and makes an online service request for a content key necessary for decrypting digital content recorded on a DCD medium (step 610). In this process, payment or settlement of content key purchase will generally be performed.

The content server then encrypts the content key requested in step 610 with the user public key of the client (step 620) and provides the encrypted content key to the client (step 630). That is, since the user public key of the client is used in step 620, it is natural that the security key generation and distribution process shown in FIG. 3 should be preceded before step 620. In this case, the user public key is provided to the content server by the security server, as described above.

Next, the content key at the client is decrypted with the user private key (step 640) and then used to decrypt the encrypted content on the DCD medium. Although FIG. 6 illustrates the acquisition of a content key online, a modified embodiment in which only the content key is purchased offline may be possible depending on the application. That is, an operation method of separately purchasing encrypted content and content key offline.

Subsequently, referring to FIG. 5, the encrypted content is read from the DCD medium at the client (step 520). Here, it is natural that data transmission and reception between the client computer and the DCD medium is performed through a DCD driver equipped with a DCD engine. The DCD driver mediates the writing and reading of data to and from the DCD medium and the transmission and reception of data between the DCD medium and the client computer.

Next, the read content is decrypted and reproduced using the content key decrypted in step 640 (step 530). In addition, the digital content in the client may be stored in the form shown in FIG. That is, the content key is stored in the form encrypted with the user public key, the content of the content is stored in the form encrypted with the content key. In this case, as described above, the secure digital content can be driven by the separate software driver in the client.

Next, the content key is decrypted and transmitted to a DCD medium through a communication channel such as USB (step 540), so that the content key is physically separated from the data area in which the encrypted content is recorded on the DCD medium, and only the DCD engine It is recorded in physically protected form in an accessible security zone (step 550). In this case, as described above, the digital content recorded on the DCD medium can be reproduced through a separate H / W driver.

Subsequently, a third embodiment in which secured digital content and a content key are distributed through an offline DCD medium will be described. 7 is a flowchart illustrating a security service method in digital content distribution through online and one-time recording media according to a third embodiment of the present invention.

First, the DCD medium on which the content key and the encrypted content are recorded is purchased offline (step 740). As described above, the encrypted content on the DCD is recorded in the data area, the content key is physically separated from the data area, and physically protected in the secure area accessible only to the DCD engine. In addition, it is natural that digital content on a DCD medium may be played offline through a separate H / W driver.

Next, the client computer reads the content key and the encrypted content recorded on the DCD medium through the DCD driver (step 720). The encrypted content is decrypted using the content key and played back (step 730). Here, in order to expand the distribution of digital content through the DCD medium, it may be desirable to restrict the content key read in step 720 not to be stored in the client computer. However, depending on the application, the content key and the content read from the DCD medium may be allowed to be stored inside the client computer. In this case, it is natural that the digital content is stored in the form of FIG. To this end, it is necessary to encrypt the content key with the public key of the client. In the process of distributing the security key of FIG. 3, the public key should be provided to the client together.

Method embodiments of the present invention may be written as a program executable in a computer system. In addition, the program can be read from a computer readable recording medium having recorded such a program and executed in a general-purpose digital computer system. Such recording media include magnetic storage media (e.g., ROM, floppy disk, hard disk, etc.), optical reading media (e.g., CD-ROM, DVD, etc.) and carrier waves (e.g., transmission over the Internet). Media is included.

So far, the present invention has been described with reference to the preferred embodiment (s). Those skilled in the art will appreciate that the present invention can be implemented in a modified form without departing from the essential features of the present invention. Therefore, the disclosed embodiments should be considered in descriptive sense only and not for purposes of limitation. The scope of the present invention is shown in the claims rather than the foregoing description, and all differences within the scope will be construed as being included in the present invention.

According to the present invention, it is possible to circulate digital content with security through an offline one-time recording medium, thereby greatly expanding the distribution of digital content. In addition, by introducing an additional public key encryption mechanism in the online distribution of digital content, the risk of illegal copying or hacking can be greatly reduced.

In addition, it creates a new distribution paradigm for digital content by configuring it to interconnect security mechanisms applied to online (including online distribution) and offline one-time recording media.

Claims (18)

In the security service method for distributing encrypted digital content, (a) generating a pair of a user public key and a user private key having a mapping relationship with each other, and providing at least the user private key to a client through a communication network; (b) receiving an online service request from the client for a content key required to decrypt specific digital content recorded on a one-time recording medium; (c) encrypting the content key requested in step (b) using the user public key generated in step (a) as an encryption key; And (d) providing the client with the content key encrypted in step (c) through a communication network; The encrypted content key in the client is decrypted using the user private key provided in step (a) as a decryption key, and then the specific digital content recorded in the one-time recording medium is decrypted using the decrypted content key. A security service method for digital content distribution through online and one-time recording media. The on-line and one-time recording medium as claimed in claim 1, wherein the specific digital content is read from the one-time recording medium, combined with the encrypted content key provided in step (d), and recorded in a storage space within the client. Service method in digital content distribution through e-mail. The method of claim 1, wherein the encrypted content key provided in step (d) is decrypted using the user private key provided in step (a) as a decryption key and then recorded on the one-time recording medium. Security service method in distribution of digital contents through recording media. 4. The security of digital content distribution through online and one-time recording media according to claim 3, wherein the decrypted content key is recorded in an area physically separated from an area in which the specific digital content is recorded in the one-time recording medium. Service method. In the security service method for distributing encrypted digital content, (a) generating a pair of a user public key and a user private key having a mapping relationship with each other, and providing at least the user private key to a client through a communication network; (b) receiving a request for purchase of specific digital content from the client; (c) encrypting the digital content requested in step (b) using a predetermined content key; (d) encrypting the content key used in the encryption process in step (c) using the user public key generated in step (a) as an encryption key; And (e) providing the digital content encrypted in step (c) and the content key encrypted in step (d) to the client through a communication network, In the client, the encrypted content key provided in step (e) is decrypted using the user private key provided in step (a) as a decryption key, and then the decrypted content key and encrypted digital provided in step (e). A method for security services in the distribution of digital content through online and one-time recording media, wherein the content is recorded on the one-time recording media. 6. The method of claim 5, wherein the decrypted content key and the encrypted digital content at the client are recorded in physically separated areas on the one-time recording medium. Security service method. 6. The security service method of claim 5, wherein the encrypted digital content provided in the step (e) is decrypted by using the decrypted content key in the client. . A security service system for distributing encrypted digital content, A security server for generating a pair of user public key and user private key having a mapping relationship to each other, and providing at least the user private key to each client through a communication network; And Upon receiving an online service request for a content key required to decrypt specific digital content recorded on a one-time recording medium, encrypting the content key using the user public key of the client as an encryption key, and encrypting the encrypted content key. It includes a content server provided to the client through, The encrypted content key in the client is decrypted using the user private key of the client as a decryption key, and then the specific digital content recorded in the one-time recording medium is decrypted using the decrypted content key. Service system. 10. The security service system of claim 8, wherein the user public key used to encrypt the content key in the content server is provided by the security server. 10. The security service system of claim 8, wherein the specific digital content is read from the one-time recording medium, combined with the encrypted content key, and recorded in a storage space in the client. The security service system of claim 8, wherein the decrypted content key is recorded in an area physically separated from an area in which the specific digital content is recorded in the one-time recording medium. A security service system for distributing encrypted digital content, A security server for generating a pair of user public key and user private key having a mapping relationship to each other, and providing at least the user private key to each client through a communication network; And Receiving a request for purchasing specific digital content from a client, encrypting the requested digital content using a predetermined content key, encrypting the predetermined content key using a user public key of the client as an encryption key, and encrypting the encrypted content. A content server for providing the digital content and the encrypted content key to the client through a communication network; And after the encrypted content key is decrypted using the user private key of the client as a decryption key, the decrypted content key and the encrypted digital content are recorded on a one-time recording medium. 13. The security service system of claim 12, wherein the public key used to encrypt the content key in the content server is provided by the security server. The security service system of claim 12, wherein the encrypted digital content is decrypted using the decrypted content key at the client. The security service system of claim 12, wherein the decrypted content key and the encrypted digital content are recorded in areas physically separated from each other on the one-time recording medium. A data area in which digital content encrypted with a predetermined content key is recorded; And A security area in which the predetermined content key is recorded; Data can be recorded only once in the empty space on the data area, The data area and the security area are physically separated from each other, The encrypted digital content recorded in the data area is decrypted using a content key recorded in the secure area. 17. The one-time recording medium of claim 16, wherein a content key necessary for decrypting encrypted digital content recorded in the data area is provided online through a communication network and recorded in the secure area. The data area and the security area of claim 16, wherein the encrypted digital content recorded in the data area and a content key necessary for decrypting the encrypted digital content recorded in the data area are provided online through a communication network. A one-time recording medium, each recorded in the recording medium.