KR101291075B1 - Method and system for selective encryption and decryption of Digital Rights Management - Google Patents

Abstract

The present invention relates to a method and system for selective encryption and decryption of digital rights management, and more particularly, to encrypt and decrypt only a specific portion of the original content, not to encrypt or decrypt the entire content in the DRM content format. By adding a regular encryption mode or an irregular encryption mode as an optional encryption information to the custom header of the header of the body, and storing one or more encryption blocks encrypted by the operation of a specific encryption algorithm in a specific portion of the original content according to the optional encryption information A method and system for selective encryption and decryption of digital rights management for generating encrypted content and performing decryption by performing an inverse operation of the encryption method for each decryption request of a client's rendering application. One will.

The present invention improves the playback speed of a large amount of content as only a specific part of the DRM content format is encrypted and decrypted, and provides various types of selective encryption and decryption methods by scalability. In particular, compared to the existing method of encrypting and decrypting the entire content, it is possible to reduce the load on the server in serving large contents and provide the effect of decrypting the contents with a low specification client.

Digital Rights Management (DRM), Selective Encryption and Decryption, Encryption Blocks

Description

Method and system for selective encryption and decryption of Digital Rights Management

1 is a block diagram showing a system for selective encryption and decryption of digital rights management according to an embodiment of the present invention;

2 is a functional block diagram illustrating an internal structure of a client according to FIG. 1;

3 is an exemplary diagram shown to explain a regular or irregular state of the selective encryption mode according to the present invention;

4 is an exemplary diagram showing the divided form of the selective encryption information according to the present invention in a regular or irregular mode,

5 is a flowchart illustrating a method for selective encryption and decryption of digital rights management according to an embodiment of the present invention;

6 is a flowchart illustrating a method of generating an encrypted content in detail in the method for selective encryption and decryption according to FIG. 5;

7 is a flowchart illustrating a method of a decryption step in detail in the method for selective encryption and decryption according to FIG. 5;

8 is a process flow diagram between systems shown to illustrate a method for selective encryption and decryption of digital rights management in accordance with a preferred embodiment of the present invention.

<Explanation of symbols for the main parts of the drawings>

100: Content Issuer

200: Rights Issuer

300: Client 301: Download Agent

302: browser 303: storage

304: DRM Agent 305: Rendering Application

The present invention relates to a method and system for selective encryption and decryption of digital rights management, and more particularly, to select a regular encryption mode or an irregular encryption mode for a custom header of a body header in a digital rights management (DRM) applied content format. Adds encrypted information and stores one or more encryption blocks encrypted by a specific encryption algorithm operation in a specific portion of the original content according to such optional encryption information. The present invention relates to a method and system for selective encryption and decryption of digital rights management for decrypting and playing back an operation.

Digital Rights Management is a new concept that emerged from the proliferation of digital contents with the spread of the Internet. Unlike analog content, digital content can be easily and quickly copied using a computer. Duplicates have a quality that is faster than the original and has a fast spreading property. This has led to users' perception that content is free on the early Internet, as well as illegal copying and abnormal distribution of content. Digital rights management is a technology that emerged to protect the rights of content creators or copyrighters associated with digital content by preventing or suppressing illegal copying and illegal distribution of such digital content.

Such digital content requires a lot of cost, effort, and time for its production, and if unauthorized copying and distribution of digital content is tolerated, it will infringe on the interests of digital content creators and reduce the creative motivation of digital content creators. This is a major obstacle to the activation of the digital content industry.

In addition, there have been efforts to protect digital contents in the past, but in the past, the main focus was on preventing unauthorized access to digital contents. In other words, access to digital content was granted only to some people who paid for it. Thus, the payer could access unencrypted digital content, and the other could not access digital content. However, when deliberately distributing digital content accessed by a payer to a third party, the third party could use the digital content without paying.

In order to solve the above problems, the concept of digital rights management (DRM) was introduced, and digital rights management allows anyone to access any encrypted digital content indefinitely, but to decrypt and play encrypted digital content, It requires a license called the Right Object. Through the application of digital rights management, digital contents can be effectively protected unlike the existing ones.

On the other hand, in the case of encrypting the content focused on the protection of the digital content as described above, especially in the case of encrypting or decrypting the entire content in the Open Mobile Alliance (OMA) DCF (DRM Content Format) 2.0, when the content is large, the server Increasing the load on the user, and the user using a client of a low specification has a problem that it takes a lot of time to perform the content decryption, causing inconvenience to the user.

Accordingly, the present invention has been made to solve the above-mentioned conventional problems, and an object of the present invention is to encrypt and decrypt only a specific portion of the original content in the DRM content format, thereby preserving the confidentiality of the content and increasing the playback speed of large contents. To provide a method and system for selective encryption and decryption of digital rights management that can be improved.

In addition, another object of the present invention is defined as a structure that is supported even in the case of not repeating a specific part regularly or irregularly in encrypting and decrypting only a specific part of the original content, and The present invention provides a method and system for selective encryption and decryption of digital rights management in which various selective encryptions according to the characteristics of content can be supported.

The present invention for achieving the above object, adds the optional encryption information to the custom header of the body header of the DRM content format, and encrypts a specific portion of the original content by the operation of a specific encryption algorithm according to the optional encryption information A content issuer that stores one or more encryption blocks to generate encrypted content; A rights object issuing server (Rights Issuer) for receiving and registering a content information registration request from the content providing server and issuing a rights object used to decrypt the encrypted content; And download and store encrypted content from the content providing server, receive and store a rights object from the rights object issuing server, and decrypt the encrypted content by performing an inverse operation of the selective encryption method for each decryption request of a rendering application. It provides a system for the selective encryption and decryption of digital rights management that comprises a;

The present invention for achieving the above object is a content providing server for selectively encrypting only a specific portion of the original content in the DRM content format and providing the generated encrypted content, which is optional in a custom header of the body header of the DRM content format. Define encryption information, wherein the encryption information is one of a regular encryption mode in which one or more encryption blocks are repeated regularly or an irregular encryption mode in which one or more encryption blocks are irregular and not repeated, and the original content according to the optional encryption information. One or more encryption blocks are located in a specific portion of the at least one encryption block, wherein all of the one or more encryption blocks are collected and encrypted through one specific encryption algorithm operation. The original encryption block contains 16 bytes of IV (Initial Vector), and subsequent encryption blocks are corrected and stored in the original data block by 16 bytes of IV. It provides a content providing server for generating encrypted content according to the selective encryption.

According to the present invention for achieving the above object, the content providing server defines the optional encryption information in the custom header of the body header of the DRM content format, and at least one encryption block in a specific portion of the original content according to the optional encryption information. Storing and generating encrypted content; Receiving, by the content providing server, a content request from a client and providing corresponding encrypted content; Requesting, by the content providing server, content information registration from a rights object issuing server and receiving a response; Receiving, by the content providing server, a right object (RO) selection from a client; Requesting, by the content providing server, a Rights Object Acquisition Protocol (ROAP) trigger according to selection of a rights object (RO) to the rights object issuing server, and receiving a ROAP trigger to the client; Requesting and issuing a rights object (RO) to the rights object issuing server by using the ROAP trigger received by the client; And decrypting the encrypted content by performing an inverse operation of the selective encryption method for each decryption request of a rendering application by using the encrypted content and the rights object RO stored by the client. Provides a method for encryption and decryption.

In addition, when the content providing server receives the content request from the client, the content providing server before the encryption is performed, the content providing server further comprises the step of generating the encrypted content by performing selective encryption in real time.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

1 is a block diagram showing a system for selective encryption and decryption of digital rights management according to a preferred embodiment of the present invention, Figure 2 is a functional block diagram showing the internal structure of the client according to FIG.

A system for selective encryption and decryption of digital rights management according to a preferred embodiment of the present invention includes a content providing server 100, a rights object issuing server 200, and a client 300, as shown in FIG. It is composed.

First, the client 300 is a wired or wireless client, and in the case of wireless, a PDA (Personal Digital Assistant), a cellular phone, a Trunked Radio System phone, a PCS phone , Global System for Mobile (GSM) phones, Wideband CDMA (W-CDMA) phones, CDMA-2000 phones, Mobile Broadband System (MBS) phones, DMB phones, and the like, where MBS phones are currently discussed. It means a mobile phone to be used in 4th generation system.

Meanwhile, as shown in FIG. 1, when the client 300 is a wired client, a user interface, that is, a personal computer (PC), is applied, and at this time, the content providing server 100 and the rights are provided through the Internet 40. The object issuing server 200 is connected.

When the client 300 is a wireless client and a communication network is applied, the content providing server 100 and the rights object issuing server 200 and the client 300 as shown in FIG. 1, a base station (BTS) Is connected via a control station (BSC) 10, a packet data service node (PDSN) 20, a data core network (DCN) 30, the Internet 40, and the communication network is a synchronous (CDMA) communication network. Is shown as an example but not limited thereto, and may be implemented as an asynchronous (W-CDMA) communication network.

When applied to an asynchronous (W-CDMA) communication network, the base station transmitter (RTS) and base station controller (RNC), Serving GPRS Support Node (SGSN), General Packet Radio Service (GPRS) network, Gateway GPRS Support Node (GGSN) Can be configured.

In addition, the mobile communication network implemented between the content providing server 100 and the rights object issuing server 200 and the client 300 includes both a synchronous (CDMA) and an asynchronous (W-CDMA) mobile communication network. It is a broad concept that includes any mobile network that relays wireless data between mobile terminals such as European GSM mobile communication network, TDMA mobile communication network, IMT-2000 mobile communication network, W-CDMA mobile communication network, CDMA mobile communication network and high-speed mobile communication network. It must be understood.

On the other hand, the selective encryption and decryption of the digital rights management of the present invention can be applied as long as it is a general file composed of a header and a body. That is, the encryption-related information is inserted into the header, and the actual encrypted payload is inserted into the body, thereby enabling selective encryption and decryption.

In the following description, the selective encryption and decryption of the present invention will be described with reference to an Open Mobile Alliance (OMA) DRM Content Format (DCF) 2.0, among other content files to which digital rights management (DRM) has been applied. Advanced Encryption Standard (DES), Data Encryption Standard (DES), SEED, etc. can be applied, but for convenience of explanation, AES will be described as an example.

The content providing server 100 adds optional encryption information to a custom header of an Open Mobile Alliance (OMA) DRM Content Format (DCF) 2.0 body header, and AES, which is a symmetric encryption algorithm, to a specific portion of the original content according to the optional encryption information. (Advanced Encryption Standard) A cryptographic content is generated by storing one or more encryption blocks encrypted through an operation.

The selective encryption information may be a regular-selective encryption mode in which one or more encryption blocks encrypted in the original content are regularly repeated, or irregular encryption in which one or more encryption blocks encrypted in the original content are irregular and not repeated. -Selective Encryption mode, Figure 3 shows a variety of examples of the regular or irregular state of the selective encryption mode according to the present invention.

Figure 4 is an exemplary diagram showing the divided form of the selective encryption information according to the present invention in a regular or irregular mode.

4 (a) shows the offset value (StartEncOffset) information of the first encrypted region, the EncLength information of each encrypted region, and the length of general data after the encrypted region in the regular encryption mode. It consists of (PlainDataTerm) information, and the string value in the custom header can be displayed as follows.

RegularEncHdr: StartEncOffset = value & EncLength = value & PlainDataTerm = value

4 (b) is composed of offset value (EncOffset) information of the region encrypted in the Irregular Encryption Mode (EncLength) information, EncLength information of the encrypted region, the string value (String Value) contained in the custom header Can be expressed as:

IrregualrEncHdr: EncOffset = value & EncLength = value & EncOffset = value & EncLength = value & EncOffset = value & EncLengh ......

FIG. 4C illustrates an embodiment in which an Irregular Encryption Mode encrypts only the upper 80 bytes of the encrypted content. The content included in the “odda” box of the DRM Content Format (DCF) is shown in FIG. 4. Same as (c) of, and String Value included in custom header can be expressed as below.

IrrequalrEncHdr: EncOffset = 0 & EncLength = 96

In addition, the encryption block is processed in units of 16 bytes to facilitate calculation of the partial block in relation to padding. For example, the encryption block is in units of 16 bytes such as 16, 32, 48, 64, and 80 bytes. Is supported.

In addition, the encryption blocks are all collected at the time of encryption, and are encrypted through only one AES operation and then stored in the original order and position. In this case, an IV (Initial Vector) is included before the first encryption block among the one or more encryption blocks. The length of the first encryption block consists of a length including the length of the IV of 16 bytes.

In addition, the encryption blocks after the first encryption block are corrected and stored in a position shifted by 16 bytes, that is, an IV size, in the original data block.

In addition, a unit of StartOffset, EncLength, PlainDataTerm, and EncOffset is byte and value: unsigned int (64).

The rights object issuing server 200 receives and registers a content information registration request from the content providing server 100 and issues a rights object used to decrypt the encrypted content.

The client 300 downloads and stores the encrypted content from the content providing server 100 and receives and stores the rights object from the rights object issuing server 200. The selective encryption scheme is used for each decryption request of a rendering application. The reverse operation is performed to decrypt and reproduce the encrypted content.

As shown in FIG. 2, the client 300 accesses the content providing server 100 to download the encrypted content, and searches the encrypted content and the rights object RO by the user. The browser 302, the storage 303 for storing the downloaded encrypted content and the rights object RO in a specific region, and downloading and storing the rights object RO in the storage 303 and decrypting each content decryption request. And a rendering application 305 for reading the encrypted content stored in the storage 303 and requesting decryption from the DRM agent 304.

The client 300 is a user terminal device capable of a wired or wireless connection. In the case of a wireless device, a PDA, a cellular phone, a common frequency communication, a PCS phone, a GSM phone, a W-CDMA phone, a CDMA-2000 phone, a MBS phone, a satellite The terminal includes a terminal, a WiBro terminal, and the like, and a personal computer, a laptop, and the like in the case of a wired line.

Next, a method for selective encryption and decryption of digital rights management according to an embodiment of the present invention having the above configuration will be described with reference to the accompanying drawings.

5 is a flowchart illustrating a method for selective encryption and decryption of digital rights management according to a preferred embodiment of the present invention, and FIG. 8 is a flowchart of processing between systems according to the present invention.

First, the content providing server 100 defines optional encryption information in a custom header of an Open Mobile Alliance (OMA) DRM Content Format (DCF) 2.0 body header, and encrypts one or more specific portions of the original content according to the optional encryption information. The block is stored to generate encrypted content (S11).

6 is a flowchart illustrating the method of the encryption generation step in detail in the method for selective encryption and decryption according to the present invention.

As shown in FIG. 6, the encrypted content generation step S11 defines one of the regular encryption mode and the irregular encryption mode as optional encryption information in the custom header of the OMA DCF 2.0 body header (S11-1). According to the encryption information, one or more encryption blocks are defined in a specific part of the original content (S11-2).

Next, the content providing server 100 collects all the one or more encryption blocks and performs an encryption process through one Advanced Encryption Standard (AES) operation (S11-3), and encrypts the encrypted block through the AES operation. 16-byte IV (Initial Vector) is included in front of the first encryption block and stored (S11-4).

The encryption blocks after the first encryption block are corrected and stored by 16 bytes of the IV in the original data block in the original order and position (S11-5).

Next, the content providing server 100 receives the content request from the client 300 and provides the corresponding encrypted content (S12). In this case, the content providing server 100 performs packaging on the content to be provided to the client 300 by using an encryption key, and such content packaging is performed at the user's request for content or before the user's request for the content. It can also be done in a batch. In addition, the content providing server 100 may have a separate presentation server.

When the content providing server 100 receives a content request from the client 300, in the case of content before encryption is performed on the corresponding content, the content providing server 100 performs encrypted encryption in real time to generate encrypted content. It can also be provided.

Next, the content providing server 100 requests the content information registration to the rights object issuing server 200 and receives a response (S13). At this time, the rights object issuing server 200 performs an information registration process of the received content in response to a request for content information registration of the content providing server 100.

In addition, the content information may be a content encryption key (CEK), DCF Hash, Content ID (Content ID) required for the rights object issuing server 200 to issue a rights object (RO) for the content. Include.

When the client 300 selects the rights object RO to obtain a license necessary for playback of the encrypted content through the search of the browser 302, the content providing server 100 receives the rights object RO from the client 300. ) Is provided (S14), a request for a Rights Object Acquisition Protocol (ROAP) trigger according to the selection of the rights object (RO) is received from the rights object issuing server 200, and is received. 300) (S15). At this time, the rights object issuing server 200 performs a ROAP trigger generation process according to the ROAP trigger request of the content providing server 100.

In addition, when the ROAP trigger request is requested from the content providing server 100 to the rights object issuing server 200, the usage right information is transmitted together.

Next, the client 300 requests and issues a rights object RO to the rights object issuing server 200 using the received ROAP trigger (S16).

At this time, the rights object issuing server 200 performs a process of packaging the rights object RO according to the request of the rights object RO of the client 300, and the rights object RO issued to the client 300. ) Is subject to Usage Rules.

Next, the client 300 decrypts the encrypted content by performing the inverse operation of the selective encryption method for each decryption request of the rendering application using the stored encrypted content and the rights object RO (S17).

7 is a flowchart illustrating a method of decrypting the selective encrypted content in detail in the method for selective encryption and decryption according to the present invention.

As shown in FIG. 7, the decryption step (S17) of the selective encrypted content is performed by the rendering application 305 reading the encrypted content stored in the storage 303 (S17-1), and then the encryption content is stored. A decryption request is made to the DRM agent 304 for a specific encryption block (S17-2).

Next, the DRM agent 304 reads the rights object RO according to the decryption request of the rendering application 305 from the corresponding specific area of the storage 303 (S17-3), and leads the rights object RO. Decrypt the specific encryption block of the encrypted content using (S17-4).

Thereafter, after the decryption of the encryption block, the DRM agent 304 repeats the decryption process for each decryption request for another encryption block of encrypted content from the rendering application 305 (S17-5).

As described above, the present invention provides a method for selectively encrypting and decrypting only a specific part of the original content, rather than encrypting or decrypting the entire content in OMA DCF 2.0, and regularly repeats or irregularly encrypts the specific part. As it is defined as a structure that can be supported even when not repeated, various optional encryption methods can be supported according to the characteristics of the content.

In addition, the present invention, in implementing the selective encryption and decryption of digital rights management, among the content files to which digital rights management (DRM) as described above, in particular OMA (Open Mobile Alliance) DCF (DRM Content Format) 2.0 and AES encryption It is not limited to the algorithm, and it should be understood that it is applicable to a general file composed of a header and a body. In particular, it is applicable to all content files to which DRM is applied. The encryption algorithm is also AES (Advanced Encryption). It should be understood that other applications such as DES (Data Encryption Standard), SEED, and the like are applicable.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. Therefore, the embodiments disclosed in the present invention are intended to illustrate rather than limit the scope of the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The protection scope of the present invention should be interpreted by the following claims, and all technical ideas within the equivalent scope should be interpreted as being included in the scope of the present invention.

As described above, according to the method and system for selective encryption and decryption of digital rights management according to the present invention, optional encryption information is added to a custom header of a body header of OMA DCF 2.0, and only a specific portion of the original content is selectively encrypted. By enabling it to be decrypted, the playback speed of a large amount of content is improved, and various forms of selective encryption and decryption methods are supported by scalability.

In addition, the present invention reduces the load on the server in serving a large volume of content compared to the existing method of encrypting and decrypting the entire content, and provides the effect that the content can be decrypted by a low specification client.

Claims (19)

Adds optional encryption information to a custom header of a body header of a DRM content format, and generates encrypted content by storing one or more encryption blocks encrypted by operation of a specific encryption algorithm in a specific portion of the original content according to the optional encryption information. A content issuer; A rights object issuing server (Rights Issuer) for receiving and registering a content information registration request from the content providing server and issuing a rights object used to decrypt the encrypted content; And Download and store encrypted content from the content providing server, receive and store a rights object from the rights object issuing server, and decode the encrypted content by performing an inverse operation according to the optional encryption information for each decryption request of a rendering application. Client to play by; System for selective encryption and decryption of digital rights management, comprising. The method of claim 1, The selective encryption information may be a regular encryption mode in which at least one encryption block encrypted in the original content is regularly repeated, or at least one encryption block encrypted in the original content may be irregular and not in an irregular encryption mode. System for selective encryption and decryption of rights management. 3. The method of claim 2, The encryption block is a system for selective encryption and decryption of digital rights management, characterized in that processed in units of 16 bytes to facilitate the calculation of the partial block in relation to the padding (Padding). 4. The method according to any one of claims 1 to 3, The first encryption block of the one or more encryption blocks includes an IV (Initial Vector), the length of the first encryption block is optional of digital rights management, characterized in that consisting of a length including the length of the IV of 16 bytes System for encryption and decryption. 3. The method of claim 2, The regular encryption mode is composed of offset value (StartEncOffset) information of the first encrypted region, length (EncLength) information of each encrypted region, and length (PlainDataTerm) information of general data after the encrypted region. System for selective encryption and decryption of digital rights management. 3. The method of claim 2, The irregular encryption mode is a system for selective encryption and decryption of digital rights management, characterized in that composed of the offset value (EncOffset) information of the encrypted region, EncLength information of the encrypted region. 5. The method of claim 4, The DRM content format is OMA (Open Mobile Alliance) DCF (DRM Content Format) 2.0 system for selective encryption and decryption of digital rights management. 5. The method of claim 4, The specific encryption algorithm is a system for selective encryption and decryption of digital rights management, characterized in that at least one of the Advanced Encryption Standard (AES), Data Encryption Standard (DES), SEED. 5. The method of claim 4, The client includes a download agent (301) for connecting to the content providing server 100 to download encrypted content; A browser 302 for searching the encrypted content and the rights object RO by the user; A storage 303 in which the downloaded encrypted contents and the rights object RO are stored; A DRM agent 304 for downloading the rights object RO, storing the rights object RO in the storage 303, and performing decryption for each content decryption request; And And a rendering application (305) for reading the encrypted content stored in the storage (303) and requesting decryption to the DRM agent (304). A content providing server for selectively encrypting only a specific portion of the original content in the DRM content format and providing the generated encrypted content. Define optional encryption information in a custom header of a body header of a DRM content format, wherein the encryption information is one of a regular encryption mode in which one or more encryption blocks are repeated regularly or an irregular encryption mode in which one or more encryption blocks are irregular and not repeated. Is selected, One or more encryption blocks are located in a specific portion of the original content according to the selective encryption information, and the one or more encryption blocks are collected and encrypted through one specific encryption algorithm operation. The encryption blocks encrypted through the specific encryption algorithm operation are stored in the original order and position of the original content, and the first encryption block includes an initial vector of 16 bytes, and subsequent encryption blocks are the original data blocks. By correcting and storing the position shifted by 16 bytes of IV by A content providing server that generates encrypted content according to performing selective encryption. The method of claim 10, The regular encryption mode is composed of the offset information (StartEncOffset) information of the first encrypted region, the length (EncLength) information of each encrypted region, the length (PlainDataTerm) information that the general data exists after the encrypted region, The irregular encryption mode is composed of the offset value (EncOffset) information of the encrypted region, the length (EncLength) information of the encrypted region, The encryption block is a content providing server, characterized in that supported only in units of 16 bytes to facilitate the calculation of the partial block in relation to the padding (Padding). The method according to claim 10 or 11, wherein The DRM content format is an OMA (Open Mobile Alliance) DCF (DRM Content Format) 2.0. The method according to claim 10 or 11, wherein The specific encryption algorithm includes at least one of an Advanced Encryption Standard (AES), a Data Encryption Standard (DES), and a SEED. A content providing server defining optional encryption information in a custom header of a body header of a DRM content format, and storing one or more encryption blocks in a specific portion of original content according to the optional encryption information to generate encrypted content; Receiving, by the content providing server, a content request from a client and providing corresponding encrypted content; Requesting, by the content providing server, content information registration from a rights object issuing server, and receiving a response; Receiving, by the content providing server, a right object (RO) selection from a client; Requesting, by the content providing server, a Rights Object Acquisition Protocol (ROAP) trigger according to selection of a rights object (RO) to the rights object issuing server, and receiving a ROAP trigger to the client; Requesting and issuing a rights object (RO) to the rights object issuing server by using the ROAP trigger received by the client; And Decrypting the encrypted content by performing an inverse operation according to the selective encryption information for each decryption request of a rendering application using the encrypted content and the rights object RO stored by the client; Method for selective encryption and decryption of digital rights management comprising a. 15. The method of claim 14, The generating of the encrypted content may include defining, as selective encryption information, one of a regular encryption mode and an irregular encryption mode in a custom header of a body header of a DRM content format; Defining locations of one or more encryption blocks in a particular portion of original content according to the optional encryption information; Collecting all of the one or more encryption blocks and encrypting the data through one specific encryption algorithm operation; Storing a 16-byte IV (Initial Vector) in front of a first encryption block among the encryption blocks encrypted through the operation of the specific encryption algorithm; And Correcting and storing the encrypted blocks after the first encryption block to a position shifted by 16 bytes of the IV in the original data block in an original order and position; The method for the selective encryption and decryption of digital rights management further comprises. 16. The method of claim 15, The decrypting of the encrypted content may include reading stored encrypted content; Requesting decryption for a specific encryption block of the encrypted content; Reading a rights object (RO) according to the decryption request; Performing decryption of a specific encryption block of an encrypted content using the read right object (RO); And After the decryption of the encryption block, the decryption block of the encrypted content is read using the rights object RO that reads the right object RO according to the decryption request for each decryption request for another encryption block of the encrypted content. Repeating the process of performing decoding; Method for the selective encryption and decryption of digital rights management comprising a. 17. The method according to any one of claims 14 to 16, When the content providing server receives the content request from the client, the content before the encryption is performed on the content, the content providing server to perform the selective encryption in real time further comprising the step of generating encrypted content further optional Method for encryption and decryption. 18. The method of claim 17, The DRM content format uses Open Mobile Alliance (OMA) DRM Content Format (DCF) 2.0. 18. The method of claim 17, The specific encryption algorithm is a method for selective encryption and decryption of digital rights management, characterized in that at least one of the Advanced Encryption Standard (AES), Data Encryption Standard (DES), SEED.

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