KR101000787B1 - Conditional access software system and the method thereof - Google Patents

Abstract

The limited software management system of the present invention includes: a demux for receiving scrambled content, a rights control message, and a rights management message from a server; A message handler for analyzing and processing the rights control message and the rights management message received by the demux; A reception restriction software manager for managing reception restriction software in response to the message processed by the message handler; A non-receipt software instance executing the non-receipt software; A download client which downloads the reception restriction software; It is characterized in that it includes an authentication client that provides a session key for performing key decryption in the conditional access software.

The reception restriction software management system and management method thereof of the present invention may define a reception restriction software and an interface providing the same, thereby establishing an interoperable download-based reception restriction system.

Authority control message, restriction software, authentication system

Description

Reception restriction software management system and its management method {CONDITIONAL ACCESS SOFTWARE SYSTEM AND THE METHOD THEREOF}

The present invention relates to a restricted software management system and a management method thereof, and more particularly to a restricted software management system that can define a restricted software and an interface providing the same, and to build an interoperable download-based restricted message system. It is about a management method.

In general, a conditional access system (CAS) is a content security solution that allows only qualified subscribers to watch the channel in a pay TV system.

Such a reception restriction system is largely composed of a scrambling process for video and data content, and encryption and decryption of restriction words and configuration keys. The headend sends scrambled content to prevent unauthorized recipients from accessing it. The scrambled content in the receiver is recovered through a descrambling process in the reception limit module of the set top box.

Most reception restriction systems use the same key as the scrambling key and the descrambling key. This is called a restriction word. The receiver transmits the restriction word used by the scrambler of the server for descrambling. For security, the receiver encrypts the control word using an authentication key and transmits it through the qualification restriction message. The authentication key is again encrypted using the subscriber's private key, the subscriber's private key, and then sent via a credential management message.

Therefore, the subscriber management system managing the customer information generates only the subscription related information and the subscriber management system according to the subscriber's subscription and withdrawal, so that the subscriber who receives or withdraws the broadcasting channel subscribed to by the new subscriber no longer receives the subscriber. The subscriber authentication system provides a function for preventing a broadcast from being received.

More specifically, the subscriber secret key is embedded in the smart card and distributed to the subscriber through the subscriber management system. When the receiver receives the entitlement control message and the entitlement management message, the key decryption process is performed in the reverse order performed by the server after checking the message. First, the authentication key is decrypted with the subscriber secret key embedded in the smart card. It then decrypts the control word with the decrypted authentication key and uses it for descrambling.

In order to prevent market monopoly by certain major system of conditional access system vendors and to eliminate the case that content users or pay TV service providers replace the set-top box itself due to the change or addition of the system, the system of receiving software based on software download It is proposed as an operable system.

In the software download-based reception restriction system, the module is loaded from the set-top box by downloading the byte code of the module that extracts the control word by decrypting the encryption management message and the encryption key inside the qualification control message in the existing reception restriction system. To run it. In particular, in an IPTV system that provides hundreds of channels and various programs in one channel, various content providers can suggest requirements for different reception restriction systems for each channel or program in one channel.

The related arts of the download-based reception restriction system focus on only how to download reception restriction software through a broadcasting network, and deal with a method of objectifying and executing newly downloaded reception restriction software when an update is required. However, as the number of channels increases, content diversification, and diversified demands on receive restriction systems, one or more vendors, systems, and versions of different receive restriction software in one set-top box must be operated in synchronization with the sender and receiver are controlled properly. A problem arises in that a word can be extracted and broadcast received.

SUMMARY OF THE INVENTION An object of the present invention is to provide a reception software management system and a management method thereof, which can define a reception restriction software and an interface providing the same, to build an interoperable download-based reception restriction system.

In order to achieve the above object, the reception control software management system of the present invention comprises: a demux for receiving scrambled content, a rights control message, and a rights management message from a server; A message handler for analyzing and processing the rights control message and the rights management message received by the demux; A reception restriction software manager for managing reception restriction software in response to the message processed by the message handler; A non-receipt software instance executing the non-receipt software; A download client which downloads the reception restriction software; It is characterized in that it includes an authentication client that provides a session key for performing key decryption in the conditional access software.

The reception software manager may include: a message delivery module configured to transfer a message received from the demux to reception software; A conditional software download module for downloading and storing the conditional software corresponding to the identifier of the conditional software; A conditional access software execution module for objectifying the downloaded conditional access software and updating the session key to execute the conditional access software; It is preferable to include a control word return module for returning an identifier derived from the reception restriction software to be executed.

The reception restriction software instance may include an authority control message authenticator for authenticating the authority control message, a first decoder for decrypting the authority control message, an authority management authenticator for authenticating the authority management message, and the authority management message. It is preferable to include a second decoder for decoding the.

In addition, in order to achieve the above object, the reception control software management method of the present invention comprises the steps of: receiving an authorization control message or an authorization management message from a demux; Obtaining a non-receipt software identifier for processing the received rights control message or rights management message; Determining whether the right control message or right management message identifier is identical to an identifier of a currently executing restriction software; If the identifier of the authority control message or the authority management message is not the same as the restriction software identifier, downloading the restriction software; It is characterized in that it comprises the step of executing the downloaded reception restriction software.

Here, if the identifier of the authority control message or the authority management message is the same as the restriction software identifier, it is preferable to further include transmitting the authority control message or the authority management message to the active reception restriction software.

More preferably, the step of downloading the reception restriction software comprises the steps of: receiving a request to download the reception restriction software having an identifier of the authorization control message or the authorization management message; Determining whether there is a reception restriction software identical to an identifier of the authority control message or the authority management message; If the same conditional access software does not exist, querying a download server address with the corresponding identifier; Requesting a bytecode of software with the queried download server address and identifier; Acquiring the bytecode of the downloaded conditional access software.

Wherein the step of executing the conditional access software comprises: stopping execution of the previous conditional access software; Creating a conditional access software object with the bytecode; Initializing an object for starting execution of the object; Updating a session key from the authentication client; It is preferable to include replacing the running conditional software.

 Here, in the step of generating an object of the non-receipt software, obtaining a control word from the object of the non-restriction software; It is preferable to include the step of transmitting the obtained control word to the demux through a message handler.

In addition, in order to achieve the above object, the digital content data access apparatus of the present invention includes a server; It is characterized in that it includes a non-receipt software management system using downloading-based non-limiting software for receiving and descrambled scrambled content from the server, and separating the decryption of the key for each layer.

The reception restriction software management system and management method thereof of the present invention may define a reception restriction software and an interface providing the same, thereby establishing an interoperable download-based reception restriction system.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. The following embodiments are provided to those skilled in the art to fully understand the present invention, and may be modified in various forms, and the scope of the present invention is limited to the embodiments described below. no.

1 is a diagram schematically showing the configuration of a conditional access software management system according to the present invention. As shown in FIG. 1, the non-receipt software management system 300 of the present invention controls the rights received together to descramble the scrambled audio / video received through the IP-tuner of the non-receipt software management system. Messages (Entitlement Control Message (ECM)) and Entitlement Management Message (EMM) are recovered using the downloaded restriction software.

The server 100 includes a scrambler 110 that performs a scrambling process for video and data content, a control word generator 120 that performs an encryption process of control words and configuration keys, and a reception limiter 130. In addition, the contents of the server and the encrypted control word, etc. are transmitted to the reception control software management system 300 through the MUX 140.

Here, the reception limiter 130 may include a first encryptor 131 for encrypting a control word using an authentication key, an authority control message generator 132 for generating the encrypted control word as an authority control message, and a subscriber. And a second encryptor 133 for encrypting the authentication key using a secret key, and a rights management message generator 134 for generating the encrypted authentication key as a rights management message.

Joining a pay TV system also receives a smart card 280 from the subscriber management system 150. The subscriber secret key is provided to the reception restriction software manager 230 to decrypt the authentication key with the subscriber secret key embedded in the smart card 280. Then, the reception restriction software manager 230 decrypts the control word with the decrypted authentication key, and transmits the decoded word to the descrambler 210 through the message handler 220 for use in descrambling.

Demux 290 receives scrambled content, rights control messages, and rights management messages sent from server 100.

The download client 270 downloads the appropriate reception restriction software through a separate IP channel when the reception restriction software capable of processing the authorization control message and the authorization management message is not stored in the terminal 200 (if it does not exist). Load. In this case, it is possible to download by using an identifier indicating a reception restriction software capable of processing the authorization control message and the authorization management message and an address of a download server capable of downloading the reception restriction software. The download client 270 performs a download in response to a download request of the reception restriction software manager 230. A detailed description of the reception restriction software manager 230 will be described later with reference to FIG. 2. The message handler 220 provides the received rights management control message and the rights management message to the restricted software instance through the restricted software manager 230.

The message handler 220 also provides the descrambler with a control word obtained from the conditional access software.

The descrambler 210 descrambles the scrambled content using the control word transmitted from the message handler 220.

The restricted software manager 230 manages restricted software in response to the message processed by the message handler 220.

2 is a diagram schematically illustrating the configuration of the reception restriction software manager 230. As shown in FIG. 2, the reception restriction software manager 230 may include a message delivery module 231 for transmitting the authorization control message and the authorization management message received from the message handler 220 to the reception restriction software instance 260. And an objectionable software download module 232 for downloading and storing the conditional access software corresponding to the conditional access software identifier capable of processing the authorization control message and the authorization management message, and the downloaded conditional access software. Control word that updates the session key (or uses the subscriber secret key) and returns the control word derived from the conditional access software execution module 233 to execute the conditional access software and the conditional access software instance 260 to execute. Return module 234.

Restriction software instance 260 executes the restriction software. In addition, it receives and decrypts the authority control message and the authority management message and returns a control word.

3 is a diagram schematically showing the configuration of a conditional software instance of the present invention. As shown in FIG. 3, the reception restriction software instance 260 is configured to decrypt an authorization control message and derive a control word using an authorization control message authenticator 261 that authenticates the authorization control message and an authentication key. A first decoder 263, a rights management authenticator 262 for authenticating the rights management message, and a second decoder 264 for decrypting the rights management message using the subscriber secret key and deriving the authentication key. do.

The download client 240 downloads the restricted software corresponding to the identifier of the restricted software that can process the rights control message and the rights management message.

Meanwhile, instead of the subscriber secret key embedded in the smart card, the authentication client 250 may provide a session key which is a seed key for decrypting the authority control message and the authority management message in the reception restriction software. have. In this case, the authority management message can be decrypted using the newly provided session key instead of the subscriber secret key. Although not shown in FIG. 1, an authentication server (not shown) may directly transmit a session key, which is a seed key for performing key decryption, to the authentication client 250.

4 is a flow chart of a method for managing a conditional access software of the present invention. As shown in FIG. 4, first, an authorization control message or an authorization management message is received from a demux (S401).

In operation S402, an identifier of a conditional access software capable of processing the received authority control message or an authority management message, that is, an access restriction software identifier corresponding to the authority control message or an authority management message, is obtained.

More specifically, the reception restriction software identifier is obtained by parsing Program Specific Information (PSI) information defined in the MPEG2 standard or by parsing a predefined authorization control message or authorization management message and recorded in the message. An identifier can be obtained.

Next, a step of determining whether or not the reception restriction software identifier and the identifier of the reception restriction software currently executed is the same (S403).

Subsequently, if the conditional access software identifier is not the same as the identifier of the current conditional access software, the operation of downloading the conditional access software corresponding to the conditional access software identifier is performed (S404). Here, it will be described in detail with reference to FIG.

5 is a flowchart of the process of downloading the conditional access software of the present invention. As illustrated in FIG. 5, the process of downloading the reception restriction software first receives a request for downloading the reception restriction software having an identifier of the authorization control message or the authorization management message (S501).

In operation S502, it is determined whether the reception restriction software having the same identifier as the reception restriction software identifier exists in the terminal.

Next, if there is no restriction software of the same identifier, a step of querying a download server address with the restriction software identifier is performed (S503).

Subsequently, the requesting bytecode of the software is performed using the queried download server address and the reception restriction software identifier (S504).

Finally, a step of acquiring the bytecode of the downloaded reception restriction software is performed (S505).

Then, the step of executing the downloaded reception restriction software (S405). Here, it will be described in detail with reference to FIG.

6 is a flowchart illustrating a process of executing the downloaded reception restriction software of the present invention. As shown in FIG. 6, the process of executing the reception restriction software first stops the execution of the reception restriction software currently being executed (S601).

Subsequently, a step of generating a reception restriction software object with the obtained bytecode is performed (S602).

In operation S603, an object for initializing execution of the downloaded reception restriction software object is initialized.

In operation S604, the session key is updated from the authentication client. This step S604 can be omitted when using the subscriber secret key as described above.

Subsequently, the step of replacing the current reception restriction software with the downloaded reception restriction software is performed (S605).

After the step (S405) of replacing or executing the downloaded reception restriction software or if the identifier of the authorization control message or authorization management message is the same as the reception restriction software identifier, the authorization restriction message or authorization management message is executed. The step of delivering to the software is performed (S406).

On the other hand, after the step of delivering to the conditional software, the process of delivering the control word generated by the result of the restricted software is further performed.

Seventh is a flow chart illustrating a process of transferring the control word of the result of the software reception restriction of the present invention. As shown in FIG. 7, in the process of executing the reception restriction software, a control word is acquired from the reception restriction software (S701), and the process of transferring the obtained control word to the demux through a message handler is performed. (S702).

Therefore, according to the present invention, it is possible to define a reception restriction software and an interface providing the same to build an interoperable download-based reception restriction system.

As described above, an embodiment of the present invention has been disclosed through the detailed description and the drawings. The terms are used only for the purpose of describing the present invention and are not used to limit the scope of the present invention as defined in the meaning or claims. Therefore, those skilled in the art will understand that various modifications and equivalent other embodiments are possible. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

1 is a diagram schematically showing the configuration of a conditional access software management system according to the present invention.

2 is a diagram schematically showing the configuration of the reception restriction software management unit.

3 is a schematic diagram illustrating the configuration of a conditional software instance of the present invention.

4 is a flowchart of a method of managing non-receipt software of the present invention.

5 is a flow chart for the process of downloading the conditional access software of the present invention.

6 is a flowchart illustrating a process of executing the conditional access software of the present invention.

7 is a flowchart illustrating a process of delivering a control word obtained by the conditional access software of the present invention.

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

220 --- message handlers

230 --- Restriction Software Management Department

240 --- download client

250 --- Authentication Client

260 --- Unrestricted Software Instance

Claims (11)

A demux for receiving scrambled content, a rights control message, and a rights management message from a server; A reception restriction software manager for acquiring an identifier indicating a reception restriction software capable of processing the received authorization control message and the authorization management message, and managing the downloaded reception restriction software corresponding to the identifier; A download client for downloading the reception restriction software corresponding to the identifier from the server; A conditional access software instance for executing the conditional access software to derive control words from the authority control message and the authority management message; A descrambler for descrambling the scrambled content using the control word; A message handler which delivers the authority control message and the authority management message received by the demux to the reception restriction software management unit and the reception restriction software instance, and delivers the derived control word to the descrambler. Restriction software management system comprising a. The method of claim 1, And a smart card authentication unit configured to authenticate with a smart card to access the subscriber management system of the server. The method of claim 1, wherein the reception restriction software management unit, A message delivery module for transmitting the authority control message and the authority management message received from the demux to the reception restriction software; A restricted software download module for downloading and storing the restricted software corresponding to the restricted software identifier; A conditional access software execution module for objectifying the downloaded conditional access software and executing the conditional access software; And a control word return module for returning a control word derived from the reception restriction software to be executed. The method of claim 1, wherein the unsubscribe software instance is: An authority control message authenticator for authenticating the authority control message, a first decoder for deriving the control word by decrypting the authority control message using an authentication key, an authority management authenticator for authenticating the authority management message, and a subscriber secret. And a second decoder which decodes the authorization management message using a key to derive the authentication key. Claims [1] A method in which a software management unit manages software for reception restriction. Receiving an authorization control message or an authorization management message from the demux; Obtaining a reception restriction software identifier indicating a reception restriction software capable of processing the received authorization control message or authorization management message; Determining whether the conditional access software identifier and the ID of the current conditional access software are the same; If the restriction software identifier is not the same as the identifier of the reception restriction software currently being executed, downloading the reception restriction software corresponding to the reception restriction software identifier; Executing the downloaded conditional access software; And transmitting the authority control message or the authority management message to the downloaded and executed reception restriction software after executing the downloaded reception restriction software. The method of claim 5, Acquiring the conditional access software identifier And parsing Program Specific Information (PSI) information defined in the MPEG2 standard or acquiring an identifier derived by parsing an authority control message or an authority management message. The method of claim 5, If the conditional access control software identifier is the same as the ID of the current execution restriction software, forwarding the authorization control message or the authorization management message to the current reception restriction software management; Way. The method of claim 5, wherein downloading the opt-out software comprises: Determining whether or not reception restriction software having the same identifier as the reception restriction software identifier exists in the terminal; Querying a download server address with the unrestricted software identifier if the same unrestricted software does not exist; Requesting a bytecode of software with the queried download server address and the unrestricted software identifier; And obtaining a bytecode of the downloaded reception restriction software. 10. The method of claim 8, wherein executing the downloaded conditional access software: Suspending execution of the currently exempt software; Generating a reception restriction software object with the obtained bytecode; Initializing an object for starting execution of the downloaded reception restriction software; And replacing the suspended reception restriction software with the downloaded reception restriction software. 6. The method of claim 5, further comprising, after the step of delivering to the opt-out software that is downloaded and executed: Acquiring a control word from a result of executing the downloaded reception restriction software; And transmitting the obtained control word to a descrambler through a message handler. A server; Obtain an identifiable software identifier that can receive scrambled content, a rights control message and a rights management message, and can process the rights control message and a rights management message, and there is no receive software of the same identifier as the obtained identifier. And a limiting software management device for downloading and executing, deriving control words from the rights control message and the rights management message to descramble the scrambled content.

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