JP4734175B2 - Content usage control system and content usage control method - Google Patents

Description

  The present invention relates to a content control apparatus or method related to a content license.

  With the spread of broadband communication services, an environment in which content distribution services for distributing various video contents to users can be operated in earnest. In general, in order to perform a content distribution service, it is necessary to control usage conditions of content and protect the content from unauthorized use. As the content usage control method, a license (that is, license information) including a decryption key for decrypting content and usage conditions regarding the content is transmitted from a server (for example, a license server) to a receiver, and the content is transmitted according to the license. A method to be used by a user is known (see, for example, Patent Document 1).

  In addition, as a content sales form, a sales form in which a plurality of contents are combined into one package to form a contract on a monthly basis, and the contract is automatically updated unless the contract is canceled can be seen.

  Here, an example of a conventional license issuing system will be described with reference to FIG.

  First, when the server of the service provider sells content CA to content CE as package P1 in X month, it issues license LA to license LE, which is the right to use content CA to content CE, to the receiver (M11). .

When the service provider's server removes the content CD from the package P1 in Y month and newly adds content CF and content CG, the license LD that is the right to use the content CD in the receiver is deleted, and the content A license LF and a license LG, which are usage rights of the CF and content CG, are issued to the receiver (M12).
Japanese Patent Laying-Open No. 2005-338979 (paragraphs [0011] to [0015]).

  In the content sales form described above, when a user uses a package, a license corresponding to each content included in the package (that is, a license that gives the user a right to use) is required. For this reason, the server issues those licenses to the receiver used by the user.

  For example, in the case of content-based license issuance and monthly contract, when content is added to a package on a monthly basis, a license corresponding to the added content is newly issued to the receiver. For this reason, there has been a burden for the receiver to perform a license update operation.

  Similarly, when a content included in a certain package is deleted, the issued license stored in the receiver is deleted by the receiver.

  The present invention has been made based on the above-described problem, and the content key of each content is set so as not to issue a new license to the user or delete the license issued to the user. The present invention provides a content usage control system and a content usage control method for issuing a license that does not include a license (ie, a package license).

  In order to solve the above-mentioned problems, the present invention provides a content usage control system in which content transmitted from a server is received by a receiver, and the receiver performs usage control related to the content. A package license generating unit configured to generate a package license including contract package information including a package identifier of the contracted package and a package provision period; and a package license transmitting the generated package license to the receiver. A transmission means; an encryption means for encrypting the material content; the encrypted material content is regarded as an encrypted content; and belonging package information having a package identifier of a package to which the content belongs and the material content are encrypted. Content that contains the content key Content license generating means for generating a license; multiplexing means for multiplexing a content license on the encrypted content; generating multiplexed content; and transmitting means for transmitting the multiplexed content to a receiver. A package license receiving unit for receiving the package license transmitted from the server; a storage unit for storing contract package information extracted from the package license and a provision period of the package in a storage unit; Content receiving means for receiving multiplexed content from, separation means for separating the multiplexed content into encrypted content and content license, means for extracting affiliation package information from the content license, and extracted affiliation Package information and Confirming whether the same package identifier is included in the contract package information stored in the storage unit, and if the same package identifier is included in the belonging package information and the contract package information, It comprises: means for extracting a content key from a content license; and decryption means for decrypting the encrypted content with a content key.

  According to a second aspect of the present invention, in the first aspect of the invention, the receiver checks whether or not the provision period of the stored package has expired, and if the provision period of the package has expired, the package The contract package information corresponding to the provision deadline and the means for deleting the provision deadline of the package from the storage unit.

  The invention according to claim 3 is the invention according to claim 1 or 2, wherein the server adds the package identifier of the package to which the content newly belongs to the belonging package information included in the multiplexed content license. Means.

  The invention according to claim 4 is the invention according to any one of claims 1 to 3, wherein the server erases a package identifier corresponding to a predetermined package from the belonging package information included in the multiplexed content license. Means.

  The invention according to claim 5 is a content usage control method in which a content transmitted from a server is received by a receiver, and the receiver performs usage control related to the content, and the package identifier of a package with which the server is contracted A package license generating step of generating a package license including contract package information and a package provision period, a package license transmitting step of transmitting the generated package license to a receiver, and the server encrypting material content An encryption step for regarding the encrypted material content as encrypted content, and belonging server information having a package identifier of a package to which the content belongs and a content key for encrypting the material content Including A content license generating step for generating a content license; a multiplexing step in which the server multiplexes a content license with the encrypted content to generate multiplexed content; and the server receives the multiplexed content in a receiver. A transmitting step for transmitting, a package license receiving step for receiving the package license transmitted from the server by the receiver, and contract package information extracted from the package license by the receiver and a provision period of the package stored in the storage unit Storage step, a content reception step in which the receiver receives multiplexed content from the server, a separation step in which the receiver separates the multiplexed content into encrypted content and a content license, and the reception Machine Extracting belonging package information from the content license, and confirming whether or not the same package identifier is included in the belonging package information extracted by the receiver and the contract package information stored in the storage unit. When the same package identifier is included in the affiliation package information and the contract package information, a step of extracting a content key from the content license and a decryption in which the receiver decrypts the encrypted content with the content key And a step.

  The invention according to claim 6 is the invention according to claim 5, wherein it is confirmed whether or not the provision period of the package stored by the receiver has expired, and if the provision period of the package has expired, A contract package information corresponding to the provision deadline and a step of deleting the provision deadline of the package from the storage unit.

  The invention according to claim 7 is the invention according to claim 5 or 6, wherein the server adds a package identifier of the package to which the content newly belongs to the belonging package information included in the multiplexed content license. A step.

  The invention according to claim 8 is the invention according to any one of claims 5 to 7, wherein the server deletes the package identifier corresponding to the predetermined package from the belonging package information included in the multiplexed content license. A step.

  According to the first and fifth aspects of the present invention, the server can generate a package license that does not include the content key, and transmit the package license to the receiver. Further, the receiver can confirm whether or not the same package identifier is included in the belonging package information and the contract package information.

  According to the second and sixth aspects of the invention, the receiver can confirm whether or not the package provision period has expired.

  According to the third and seventh aspects of the present invention, the server can add information related to a package to which a certain content newly belongs to the content license.

  According to the fourth and eighth aspects of the present invention, the server can delete the information about the package whose service provision period has expired from the content license.

  As described above, according to the inventions of claims 1 and 5, since the content key is not included in the package license, the package license is not updated even if the content is encrypted by changing the content key to another content key. In addition, the receiver can use the content and determine whether the content is usable by the receiver.

  According to the second and sixth aspects of the invention, the receiver can manage the expiration date of the contract package information.

  According to the third and seventh aspects of the present invention, since the content license information is not included in the package license, the content usable by the user can be added to the package without updating the package license.

  According to the fourth and eighth aspects of the present invention, since the content license information is not included in the package license, the content can be deleted from the package so that the user cannot use it without updating the package license.

  These can contribute to the content provision service field.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  A basic content control method in this embodiment will be described with reference to FIG. In the following description, a package is a sales unit including contents (for example, a sales unit including two or more contents).

  When the server of the service provider collects the contents CA to CE and generates the package P1 and sells the package P1 in X month, it issues a package license LP1 that is the right to use the package P1 to the receiver (M21). ).

  Then, even if the service provider removes the content CD from the package P1 and adds new content CF and content CG in month Y, a new license is not sent (M22).

  The apparatus configuration of the content usage control system in this embodiment will be described with reference to FIG. The apparatus configuration of the content usage control system is mainly composed of a server 100 and a receiver 200.

  Further, the server 100 acquires material content (for example, content that can be used on a network such as still image data and moving image data) from the material content management unit, encrypts the material content, and encrypts the material content (hereinafter referred to as “content”). An encryption unit 101 that generates encrypted content), a multiplexing unit 102 that multiplexes a content license with the encrypted content to generate multiplexed content, and a content transmission unit 103 that transmits the multiplexed content to the receiver 200. A content license generation unit 104 that generates a content license, a package license generation unit 105 that generates a package license, and a package license transmission unit 106 that transmits the package license to the receiver 200. The material content management means is, for example, a database for managing material content.

  The receiver 200 includes a content reception unit 201 that receives multiplexed content from the server 100, a separation unit 202 that separates encrypted content and content licenses from the multiplexed content, a decryption unit 203 that decrypts encrypted content, and a package The license processing unit 204 that receives the license and the content license, determines whether the content can be used, and transmits the content key to the decryption unit 203, the package license reception unit 205 that receives the package license from the server 100, and the license processing unit 204 A storage unit 206 for storing the results.

  Note that the storage unit 206 includes a storage device (for example, a hard disk or a memory). The content key is a key used for encrypting and decrypting the content. For example, the content key in the common key cryptosystem uses the same key for the server and the receiver. The content key in the public key cryptosystem is a key pair. The server uses the public key to encrypt the content, and the receiver uses the secret key to decrypt the content.

  Next, the configuration of the package license LP1 transmitted from the server 100 to the receiver 200 will be described with reference to FIG. The package license LP1 includes contract package information LPa having a package identifier PKa of the package to which the usage right is given, and a provision period LPb of the package.

  Note that the communication between the server 100 and the receiver 200 may be performed by a method in which security is ensured by, for example, SSL (Secure Socket Layer).

  Further, the package provision deadline LPb is a monthly contract and, in a sales form in which the contract is automatically renewed unless canceled, the deadline for providing the package to the user (for example, the period after the purchase of the package ( That is, a value indicating a date after a period longer than the contract unit).

  Next, the configuration of the content licenses LA to LC transmitted from the server 100 to the receiver 200 will be described with reference to FIG. Hereinafter, the content license LA will be described as an example. The content license LA is composed of belonging package information CLa indicating a package to which the multiplexed encrypted content belongs, and a content key CLb for decrypting the multiplexed encrypted content. For example, when content is included in a plurality of packages, belonging package information including a plurality of package identifiers is described in the content license.

  In addition, in the contents CA to CE included in the same package, the same package identifier PKa is included in the affiliation package information CLa of the content license multiplexed with each content. When a certain content is included in a plurality of packages, a plurality of package identifiers PKa may exist in the belonging package information CLa for the content license multiplexed into the content.

  When replacing the content included in a certain package, the content is added to or deleted from the package by adding or deleting the package identifier PKa to the belonging package information CLa in the content license multiplexed in the content. Or erase from. For example, when deleting the content CA included in the package P1 from the package P1, the package identifier PKa indicating the package P1 in the belonging package information CLa of the content license LA to be multiplexed with the content CA is deleted. In addition, when a content CB not included in the package P1 is added to the package P1, a package identifier PKa representing the package P1 is added to the package CLa to which the content license LB to be multiplexed on the content CB belongs.

  As a specific method of realizing the package identifier PKa, for example, an identifier that identifies a package by an ID (Identifier) based on a combination of a character code or a numeric code, or an identifier that identifies a package by each bit constituting a bit string Realize. Further, the belonging package information CLa and the contract package information LPa may include one or more package identifiers PKa.

  The operation until the server 100 generates a package license and transmits it to the receiver 200 will be described with reference to FIG. In the following description, the same reference numerals as those in FIGS. 1 to 3 are omitted.

  First, the package license generation unit 105 generates the package license LP1 including the contract package information LPa having the package identifier PKa of the contracted package and the package provision period LPb (S301).

  Next, the generated package license LP1 is transmitted to the package license receiving unit 205 provided in the receiver 200 (S302). Note that the timing for transmitting the package license LP1 may be, for example, a timing requested from the receiver 200 to the server 100 or an arbitrary timing transmitted from the server 100 to the receiver 200. A plurality of package licenses can be transmitted from the server 100 to the receiver 200.

  The operation until the server 100 generates a content license and transmits the content license to the receiver 200 will be described with reference to FIG.

  First, the encryption unit 101 encrypts material content to generate encrypted content (S401).

  Next, a content license LA including the content key CLb used for content encryption and the belonging package information CLa is generated (S402). Note that a content key CLb that has been created in advance may be acquired.

  Next, the encrypted content and the generated content license LA are multiplexed to generate multiplexed content (S403).

  Then, the multiplexed content is transmitted to the content receiving unit 201 of the receiver 200 (S404). Note that the timing for transmitting the multiplexed content may be, for example, a timing requested from the receiver 200 to the server 100 or an arbitrary timing transmitted from the server to the receiver 200.

  The operation of the license processing unit 204 when the receiver 200 receives a package license from the package license receiving unit 205 will be described with reference to FIG.

  First, the license processing unit 204 receives the package license LP1 from the package license receiving unit 205 (S501).

  Next, the contract package information LPa and the package provision period LPb are extracted from the received package license LP1 (S502). For example, if the received package license LP1 is encrypted, after the package license is decrypted, the contract package information LPa and the package provision time limit LPb are extracted. Further, as a key for encrypting the package license LP1, for example, a unique key of the receiver 200 (that is, a unique key of the receiver 200 registered in advance in the server 100) may be used.

  Then, the contract package information LPa and the package provision period LPb are stored in the storage unit 206 (S503).

  The operation of the license processing unit 204 when the receiver 200 receives a content license from the separation unit 202 will be described with reference to FIG.

  First, the license processing unit 204 receives the content license LA from the separation unit 202 (S601).

  Next, the belonging package information CLa is extracted from the received content license LA (S602). If the content license LA is encrypted, the belonging package information CLa is extracted after the content license LA is decrypted. Further, as a key for encryption, for example, a content sender key (that is, a content sender key acquired in advance from a server) may be used.

  Next, it is confirmed whether or not the same package identifier PKa is included in the contract package information LPa stored in the storage unit 206 and the extracted belonging package information CLa (S603). If the same package identifier PKa is included in the contract package information LPa and the belonging package information CLa, the process proceeds to step S604. If the same package identifier PKa is not included in the contract package information LPa and the affiliation package information CLa, the process is terminated.

  In step S604, it is confirmed whether or not the package provision period LPb has expired. For example, the method for confirming the package provision deadline compares the time obtained from the standard time acquisition means (for example, a standard time server on the Internet) with the provision deadline, and considers the case where the provision deadline has passed as invalid. If the provision deadline has not passed, it is confirmed by a method that is considered valid. If the package provision period is valid, the process proceeds to step S605. If the package provision period LPb is invalid, the process proceeds to step S607.

  In step S605, the content key CLb is extracted from the content license LA.

  Then, the content key CLb is transmitted to the decryption unit, and the process ends (S606).

  In step S607, if the package provision time limit LPb is invalid, the invalidated contract package information LPa and the package provision time limit LPb are deleted from the storage unit 206, and the process ends.

  The server that transmits the package license LP1 and the server that transmits the content license LA may be the same device or different devices.

  A computer program describing a method related to the content usage control system described above may be implemented so as to access a memory or an external storage device that stores input / output data required for the method related to the content usage control system.

  As described above, in the present embodiment, the content license including the belonging package information is multiplexed and transmitted from the server to the receiver.

  Therefore, in the download service and the video-on-demand service, when replacing the content included in the package, the content can be replaced without updating the license issued from the service provider to the user.

  Although the present invention has been described in detail only for the specific examples described above, it is obvious to those skilled in the art that various changes and modifications are possible within the scope of the technical idea of the present invention. Such variations and modifications are naturally within the scope of the claims.

  For example, as a modification of the present embodiment, a public key cryptosystem may be used for encryption. That is, the package license may be encrypted with the user's public key registered in the server, and the package license may be decrypted with the private key registered in the receiver.

The block diagram of the content utilization control system in this embodiment. The block diagram of the package license in this embodiment. The block diagram of the content license in this embodiment. The server package license processing flowchart in this embodiment. The server content license processing flowchart in this embodiment. 6 is a package license processing flowchart of the receiver in the present embodiment. The content license processing flowchart of the receiver in this embodiment. The conceptual diagram of a general license issuing system. The conceptual diagram of the basic content control system of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 ... Server 101 ... Encryption part 102 ... Multiplexing part 103 ... Content transmission part 104 ... Content license generation part 105 ... Package license generation part 106 ... Package license transmission part 200 ... Receiver 201 ... Content reception part 202 ... Separation part 203 ... Decryption unit 204 ... License processing unit 205 ... Package license reception unit 206 ... Storage unit CA to CG ... Content CLa ... Affiliated package information CLb ... Content key LA-LG ... Content license LP1 ... Package license LPa ... Contract package information LPb ... Expiration date P1 ... Package PKa ... Package identifier

Claims (8)

A content usage control system in which content transmitted from a server is received by a receiver, and the receiver performs usage control related to the content,
The server is
Package license generation means for generating a package license including contract package information having a package identifier of the contracted package and a package provision period;
A package license transmitting means for transmitting the generated package license to the receiver;
An encryption means for encrypting the material content and regarding the encrypted material content as encrypted content;
Content license generating means for generating a content license including a package key of a package to which the content belongs and a content key for encrypting the material content;
Multiplexing means for multiplexing a content license with the encrypted content and generating multiplexed content;
Transmitting means for transmitting the multiplexed content to a receiver,
The receiver is
A package license receiving means for receiving a package license transmitted from the server;
Storage means for storing the contract package information extracted from the package license and the provision period of the package in the storage unit;
Content receiving means for receiving multiplexed content from the server;
Separation means for separating the multiplexed content into encrypted content and a content license;
Means for extracting affiliation package information from the content license;
It is confirmed whether or not the same package identifier is included in the extracted belonging package information and the contract package information stored in the storage unit, and the same package identifier is included in the belonging package information and the contract package information. If included, means for extracting a content key from the content license;
A content use control system comprising: decrypting means for decrypting the encrypted content with a content key. The receiver is
It is checked whether or not the provision period of the stored package has expired. If the provision period of the package has expired, the contract package information corresponding to the provision period of the package and the provision period of the package are deleted from the storage unit. means,
The content usage control system according to claim 1, further comprising: The server is
Means for adding the package identifier of the package to which the content newly belongs to the belonging package information included in the multiplexed content license;
The content usage control system according to claim 1 or 2, further comprising: The server is
Means for deleting a package identifier corresponding to a predetermined package from the belonging package information included in the multiplexed content license;
The content usage control system according to any one of claims 1 to 3, further comprising: A content usage control method in which content transmitted from a server is received by a receiver, and the receiver performs usage control regarding the content,
A package license generating step for generating a package license including contract package information having a package identifier of a package contracted by the server and a provision period of the package;
A package license sending step in which the server sends the generated package license to a receiver;
An encryption step in which the server encrypts the material content and regards the encrypted material content as encrypted content;
A content license generating step in which the server generates a content license including content package information having a package identifier of a package to which the content belongs and a content key for encrypting the material content;
A multiplexing step in which the server multiplexes a content license with the encrypted content and generates multiplexed content;
A transmitting step in which the server transmits the multiplexed content to a receiver;
A package license receiving step in which the receiver receives a package license transmitted from the server;
Storing the contract package information extracted from the package license by the receiver and the provision period of the package in a storage unit;
A content receiving step in which the receiver receives the multiplexed content from the server;
A separation step in which the receiver separates the multiplexed content into encrypted content and a content license;
The receiver extracting affiliation package information from the content license;
The receiver confirms whether the same package identifier is included in the belonging package information extracted by the receiver and the contract package information stored in the storage unit, and in the belonging package information and the contract package information If the same package identifier was included, extracting a content key from the content license; and
A decrypting step in which the receiver decrypts the encrypted content with a content key;
A content usage control method characterized by comprising: It is confirmed whether or not the provision period of the package stored by the receiver has expired. When the provision period of the package has expired, the contract package information corresponding to the provision period of the package and the provision period of the package are stored. The steps to erase from the part,
The content usage control method according to claim 5, further comprising: Adding a package identifier of a package to which the content newly belongs to the belonging package information included in the content license multiplexed by the server;
7. The content use control method according to claim 5 or 6, characterized by comprising: Erasing a package identifier corresponding to a predetermined package from the belonging package information included in the content license multiplexed by the server;
The content use control method according to claim 5, wherein the content use control method is provided.

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