KR101223280B1 - System and method for conditional access setting of digital multimedia broadcasting - Google Patents

Abstract

The present invention discloses a digital broadcasting CA control system and method thereof. That is, according to a scrambling request, a control word that is required to be updated when a preset event is generated is generated to perform scrambling on the MOT object based on the generated control word, and an entitlement control message (ECM, Entitlement) generated based on the control word. When the control word is replaced according to the time period by receiving the control message) in synchronization with the MOT object in which the scrambling is performed, the control word is replaced before the MOT object is completely received and the MOT object must be newly received. You can prevent it.

Terrestrial Digital Multimedia Broadcasting (T-DMB), Restricted Reception, Control Word (CW), Scrambling

Description

Digital broadcasting CA control system and method thereof {SYSTEM AND METHOD FOR CONDITIONAL ACCESS SETTING OF DIGITAL MULTIMEDIA BROADCASTING}

The present invention relates to a limited reception method of terrestrial digital multimedia broadcasting (T-DMB), and more particularly, to an event reference for limited reception in a multimedia object transmission (MOT) mode among various service layers and characteristics of terrestrial DMB broadcasting. The present invention relates to a digital broadcast CA control system and method for setting CA reception by applying an event-driven CW change method.

In the general configuration of a conventional conditional access system (CAS), a control word generator generates a control word (CW, Control Word) necessary to perform scrambling of content in a scrambler and Pass to Synchronizer. In this regard, the synchronizer synchronizes the scrambling process in the scrambler and the message generation process for delivering the control word in the CA Message Encoder, and decodes the CA message at the receiving end to decode the content. Descrambling is synchronized.

In this case, the general CA system performs a function of protecting continuous broadcasting content such as video or audio, and periodically replaces control words to enhance security. The control word replacement cycle varies depending on the conditional access system and its configuration, and often has a period of several seconds to several minutes.

However, the periodic control word replacement can operate smoothly for continuous broadcasting content such as video or audio, but the time-based period when transmitting contents of multimedia object transfer (MOT) method within the terrestrial DMB standard Problems can arise when regular control words are replaced.

In other words, the MOT has a finite length format and must be completely received and stored in the terminal before a user request for use or presentation on the screen. If the control word is replaced according to a time period when the MOT is applied to the limited reception, there may be a case where the control word is replaced before the MOT object is completely received and a new MOT object must be received. That is, a situation may occur in which the MOT object is continuously re-received or a specific MOT object is not continuously received even though the contents of the MOT object or the access rule are not changed.

The present invention was created to solve the problems inherent in the prior art as described above, and an object of the present invention is to provide a time-driven CW change method for performing multimedia object transfer (MOT) scrambling. Rather, the present invention provides a digital broadcast CA control system and method for setting CA reception by applying an event-driven CW change method based on event.

According to an aspect of the present invention for achieving the above object, there is provided a system for setting up digital broadcast limited reception: The system comprises a data source as a multimedia object transfer (MOT) object subject to reception restriction and scrambling the configured MOT object. A data encoder requesting the request; Generates a control word that is required to be updated when a preset event occurs according to the scrambling request, performs scrambling on the MOT object based on the generated control word, and an entitlement control message generated based on the control word (ECM, Entitlement Control) A scrambler that receives a message and delivers the message to the data encoder in synchronization with the MOT object on which the scrambling is performed; And a conditional access server which generates the entitlement control message including the generated control word and access authority information (Access Criteria) and transmits the entitlement control message to the scrambling unit.

Preferably, the scrambling unit may perform the scrambling by newly generating the control word according to occurrence of the preset event including a change of the MOT object and a change of the access right information.

According to another aspect of the present invention, a scrambler is provided: The apparatus is controlled to update when a preset event occurs in response to a scrambling request for a multimedia object transfer (MOT) object subject to reception restriction received from a data encoder. Control word generation unit for generating a word; A scrambling unit that performs scrambling on the MOT object based on the generated control word; And transmitting the generated control word to receive an entitlement control message (ECM) including the control word and access authority information (Access Criteria) from the CA, and synchronizing with the MOT object on which the scrambling is performed. It characterized in that it comprises a synchronization unit for transmitting to the data encoder.

Preferably, the control word generator, characterized in that for receiving the scrambling request for the MOT object corresponding to the data body list (Body List) included in the MOT data carousel (Carousel).

Preferably, the control word generation unit, characterized in that for generating the control word at the initial reception of the data body list of the MOT data carousel.

Preferably, the control word generation unit, characterized in that for generating a new control word in accordance with the occurrence of the predetermined event including the change of the data body list and the change of the access authority information.

According to another aspect of the present invention, there is provided a method for setting digital broadcast limited reception, comprising: an object constructing step of a data encoder configuring a data source into a multimedia object transfer (MOT) object to which reception is restricted; A scrambling request step of the data encoder requesting scrambling for a MOT object; A control word generation step of a scrambler generating a control word that is required to be updated according to a preset event occurrence according to the scrambling request; Performing a scrambling step of requesting a qualification control message by delivering the generated control word for scrambling the MOT object based on the generated control word; A qualification control message transmission step of the CA receiving and generating the credential control message including the control word and access authority information (Access Criteria) according to the credential control message request and transmitting the credential control message to the scrambling unit; And a request value transfer step of the scrambler transferring the entitlement control message to the data encoder in synchronization with the MOT object on which the scrambling is performed.

Preferably, the method may further include a control word update step of newly generating the control word according to the occurrence of the preset event including a change of the MOT object and a change of the access right information.

According to another aspect of the present invention, there is provided a method for setting up digital broadcast limited reception, comprising: a scrambling request reception step of receiving a scrambling request for a multimedia object transfer (MOT) object subject to reception restriction from a data encoder; A control word generation step of generating a control word that is required to be updated according to a preset event occurrence according to the scrambling request; A scrambling step of scrambling the MOT object based on the generated control word; A qualification control message receiving step of transmitting the generated control word and receiving an entitlement control message (ECM) including the control word and access authority information (Access Criteria) from a CA; And a request value transfer step of transferring the entitlement control message in synchronization with the data encoder of the MOT object on which the scrambling has been performed.

Preferably, the method may further include a control word update step of newly generating the control word according to the occurrence of the preset event including a change of the MOT object and a change of the access right information.

Preferably, the scramble request receiving step, characterized in that for receiving a scrambling request for the MOT object corresponding to the data body list (Body List) included in the MOT data carousel (Carousel).

Preferably, the control word generation step, characterized in that for generating the control word at the initial reception of the data body list of the MOT data carousel.

Preferably, the control word update step, characterized in that for generating a new control word in accordance with the occurrence of the predetermined event including the change of the data body list and the change of the access rights information.

The system of the present invention and the method for setting the digital broadcast CA control method are not event-driven CW change methods for performing MOT scrambling, but event-based control word replacement (Event-). By setting the restricted reception by applying the driven CW change method, it is possible to prevent the problem that the control word is replaced before the MOT object is completely received and the MOT object is newly received when the control word is replaced according to the time period. .

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

1 is a schematic block diagram of a system for setting up digital broadcast limited reception according to an embodiment of the present invention.

As shown in FIG. 1, the system includes a data encoder 100 constituting a multimedia object transfer (MOT) object that is subject to reception restriction; A scrambler (200) for performing scrambling on the MOT object; And a conditional access server 300 generating an entitlement control message (ECM).

The data encoder 100 configures a data source as a multimedia object transfer (MOT) object that is subject to reception restriction, and requests the scrambler 200 to scrambling the configured MOT object. More specifically, the data encoder 100 configures a data source as the MOT object and configures the configured MOT object as a MOT directory data carousel. Based on this, the data encoder 100 transmits a MOT object to the scrambler 200, that is, a data body list that is subject to reception restriction included in the MOT data carousel and requests scrambling.

The scrambler 200 generates a control word (CW, Control Word) for scrambling according to the scrambling request received from the data encoder 100, and performs scrambling on the MOT object based on this. More specifically, the scrambler 200 generates a control word that is required to be updated when a preset event occurs at the initial reception of the MOT object, that is, the data body list of the MOT data carousel corresponding to one service. Based on this, the scrambler 200 scrambles the MOT bodies in the data body list that are subject to reception restriction based on the generated control word. In addition, the scrambler 200 transmits the generated control word to the conditional access server 300 to limit an entitlement control message (ECM) including the transmitted control word and access rights information (Access Criteria). Received from the receiving server 300. Based on this, the scrambler 200 synchronizes the entitlement control message with the MOT bodies on which the scrambling has been performed, and returns the MOT body and the entitlement control message on which the scrambling is performed to the data encoder 100. Meanwhile, the scrambler 200 receives corresponding change information from the data encoder 100 according to occurrence of the preset event, for example, modification, deletion, or addition of a specific MOT body in the data body list, or a corresponding service. When the access right information is changed and the change information is received from the CA 300, the existing process is stopped and the control word is newly generated so that scrambling is performed.

The conditional access server 300 generates the entitlement control message including a control word and access rights information (Access Criteria). More specifically, the conditional access server 300 receives the control word generated from the scrambler 200, generates a credential control message including the received control word and access authority information and returns to the scrambler 200. . Meanwhile, the conditional access server 300 transmits the change information for notifying when the access right information (Access Criteria) is changed to the scrambler 200 so that the control word is newly updated.

Hereinafter, a detailed configuration of the scrambler 200 will be described with reference to FIG. 2. That is, the scrambler 200 includes a control word generator 210 for generating a control word for scrambling; A scrambling unit 220 that performs scrambling on the MOT object; And a synchronization unit 230 for synchronizing an entitlement control message (ECM) with the MOT object on which scrambling is performed.

The control word generator 210 generates a control word for scrambling according to a scrambling request received from the data encoder 100, and performs scrambling on the MOT object based on this. More specifically, the control word generation unit 210 generates a control word that is required to be updated when a preset event occurs at the initial reception of the MOT object, that is, the data body list of the MOT data carousel corresponding to one service.

The scrambling unit 220 performs scrambling on the MOT object based on the generated control word. More specifically, the scrambling unit 220 scrambles the MOT objects, that is, the MOT bodies in the data body list to which the reception restriction is applied, based on the control words generated by the control word generation unit 210.

The synchronization unit 230 transmits the generated control word to the limited reception server 300 to limit an entitlement control message (ECM) including the transmitted control word and access rights information (Access Criteria). Received from the receiving server 300. Based on this, the synchronization unit 230 synchronizes the entitlement control message with the MOT bodies on which the scrambling has been performed, and returns to the data encoder 100 the MOT body and the entitlement control message on which the scrambling has been performed.

On the other hand, the control word generator 210 receives the corresponding change information from the data encoder 100 in accordance with the occurrence of the predetermined event, for example, the change, modification, deletion, addition of a specific MOT body in the data body list, Alternatively, when the access right information for the corresponding service is changed and the change information is received from the CA 300, the existing process is stopped and the control word is newly generated so that scrambling is performed.

As described above, according to the digital broadcasting CA system, the event-driven CW change method, rather than the time-driven CW change method, is used. By applying MOT (Multimedia Object Transfer) scrambling, if the control word is replaced according to a time period, the control word is replaced before the MOT object is completely received, thereby preventing the problem of receiving a new MOT object. . That is, it is possible to prevent a situation in which the MOT object is continuously re-received or the specific MOT object is not continuously received even though the contents of the MOT object or the access rule are not changed.

Hereinafter, with reference to FIG. 3 and FIG. 4, a method for setting up digital broadcasting limited reception according to an embodiment of the present invention will be described. Here, for the convenience of description, the configuration shown in FIGS. 1 and 2 will be described with reference to the corresponding reference numerals.

First, referring to FIG. 3, a driving method of the digital broadcast CA control system will be described.

First, the data encoder 100 configures the data source as a multimedia object transfer (MOT) object to which the reception restriction is applied (S110). Preferably, the data encoder 100 configures a data source as the MOT object and configures the constructed MOT object as a MOT directory data carousel.

Then, the data encoder 100 requests scrambling for the MOT object (S120). Preferably, the data encoder 100 transmits a MOT object to the scrambler 200 to request a scrambling by transmitting a data body list that is subject to reception restriction included in the MOT data carousel.

Then, the scrambler 200 generates a control word that is required to be updated according to the preset event occurrence according to the scrambling request (S130). Preferably, the scrambler 200 generates a control word that is required to be updated when a preset event occurs at the initial reception of the MOT object, that is, the data body list of the MOT data carousel corresponding to one service.

Next, the scrambler 200 performs scrambling on the MOT object based on the generated control word, and transmits the generated control word to the conditional access server 300 to request a qualification control message (S140-S150). ).

Then, the CA 300 generates a credential control message including the control word and access rights information (Access Criteria) according to the credential control message request, and transmits the credential control message to the scrambling unit 200 (S16-S170). ).

Thereafter, the scrambler 200 returns the entitlement control message to the data encoder 100 in synchronization with the MOT object on which the scrambling is performed (S180-S190).

Meanwhile, the scrambler 200 newly generates the control word according to the occurrence of the preset event including the change of the MOT object and the change of the access right information (S200). Preferably, the scrambler 200 receives corresponding change information from the data encoder 100 in response to occurrence of the preset event, for example, a change, modification, deletion, or addition of a specific MOT body in the data body list, or When the access right information for the corresponding service is changed and the change information is received from the CA, 300, the existing process is stopped and the control word is newly generated so that scrambling is performed.

Hereinafter, a specific driving method of the scrambler 200 will be described with reference to FIG. 4.

First, a control word for scrambling is generated according to a scrambling request for a multimedia object transfer (MOT) object that is subject to reception restriction (S210-S220; corresponding to steps S120-S130 of FIG. 3). Preferably, when the control word generation unit 210 receives an MOT object received from the data encoder 100, that is, a data event list of a data body list of a MOT data carousel corresponding to one service, an update request is generated when a preset event occurs. Create a control word.

Then, scrambling is performed on the MOT object based on the generated control word (S240; corresponding to step S140 of FIG. 3). Preferably, the scrambling unit 220 scrambles the MOT object, that is, the MOT bodies in the data body list to which the reception restriction is applied, based on the control word generated by the control word generation unit 210.

The generated control word is transmitted to receive an entitlement control message (ECM) including the control word and access authority information (Access Criteria) from the CA server 300 (S250-S270; FIG. 3). Corresponding to steps S150-S170). Preferably, the synchronization unit 230 transmits the generated control word to the CA server 300, and includes an entitlement control message (ECM) including the transmitted control word and access rights information (Access Criteria). ) Is provided from the CA 300.

Thereafter, the entitlement control message is transferred to the data encoder in synchronization with the MOT object on which the scrambling has been performed (S280-S290; corresponding to steps 'S180-S190' of FIG. 3). Preferably, the synchronization unit 230 synchronizes the entitlement control message with the MOT bodies on which the scrambling has been performed, and returns to the data encoder 100 the MOT body and the entitlement control message on which the scrambling has been performed.

On the other hand, the control word generator 210 receives the corresponding change information from the data encoder 100 in accordance with the occurrence of the predetermined event, for example, the change, modification, deletion, addition of a specific MOT body in the data body list, Alternatively, when the access right information for the corresponding service is changed and the change information is received from the CA 300, the existing process is stopped and the control word is newly generated to perform scrambling (S300; Corresponding to S200 ').

As described above, according to the digital broadcasting CA control method according to the present invention, the event-driven CW change method, rather than the time-driven CW change method, is used. By applying MOT (Multimedia Object Transfer) scrambling, if the control word is replaced according to a time period, the control word is replaced before the MOT object is completely received, thereby preventing the problem of receiving a new MOT object. . That is, it is possible to prevent a situation in which the MOT object is continuously re-received or the specific MOT object is not continuously received even though the contents of the MOT object or the access rule are not changed.

Meanwhile, the steps of a method or algorithm described in connection with the embodiments disclosed herein may be embodied directly in hardware, in a software module executed by a processor, or in a combination of both. A software module may reside in a RAM memory, a flash memory, a ROM memory, an EPROM memory, an EEPROM memory, registers, a hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art. An exemplary storage medium is coupled to the processor such that the processor can read information from, and write information to, the storage medium. Alternatively, the storage medium may be integrated into the processor. The processor and the storage medium may be included within an ASIC. The ASIC may be included in the terminal. In the alternative, the processor and the storage medium may reside as discrete components in a terminal.

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, but, on the contrary, It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

The digital broadcasting CA system and the method according to the present invention have overcome the limitations of the existing technology in that an event-driven CW change method is applied to perform scrambling. It is an invention that is industrially applicable because not only the use but also the possibility of commercialization or operation of the applied device is not only sufficient, but also practically obvious.

1 is a schematic block diagram of a system for setting up digital broadcast limited reception according to an embodiment of the present invention.

2 is a schematic configuration diagram of a scrambler according to an embodiment of the present invention.

3 and 4 are schematic flow charts for explaining a digital broadcast CA control method according to an embodiment of the present invention.

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

100: data encoder

200: scrambler

210: control word generation unit 220: scrambling unit

230: synchronization unit

300: restricted receiving server

Claims (13)

A data encoder configured to configure a data source as a multimedia object transfer (MOT) object to request scrambling of the configured MOT object; According to the scrambling request, scrambling is performed on the MOT object based on a control word, and receives an entitlement control message (ECM) generated based on the control word to synchronize with the MOT object on which the scrambling is performed. A scrambler for transmitting to the data encoder; And It includes a restriction receiving server for generating the entitlement control message including the control word and access rights information (Access Criteria) and delivers to the scrambler, And the scrambler updates and uses the control word when a predetermined specific event occurs. The method of claim 1, The preset specific event, And a change of the MOT object and a change of the access right information. A control word generator configured to generate a control word according to a scrambling request for a multimedia object transfer (MOT) object received from a data encoder; A scrambling unit that performs scrambling on the MOT object based on the control word; And The MOT object to which the scrambling is performed by transmitting the control word to the CA and receiving an entitlement control message (ECM) including the control word and the access authority information (Access Criteria) from the CA. And a synchronization unit for transmitting the synchronized entitlement control message and the scrambling MOT object to the data encoder. The control word generator is a scrambler, characterized in that for updating the control word when a predetermined event occurs. The method of claim 3, wherein The control word generation unit, And a scrambling request for the MOT object corresponding to a data body list included in a MOT data carousel. 5. The method of claim 4, The control word generation unit, The scrambler, characterized in that for generating the control word at the initial reception of the data body list of the MOT data carousel. The method of claim 3, wherein The preset specific event, And a change of the MOT object and a change of the access right information. An object construction step of the data encoder configuring the data source as a multimedia object transfer (MOT) object; A scrambling request step of the data encoder requesting scrambling for the MOT object; A control word generation step of the scrambler generating a control word according to the scrambling request; A scrambling step of scrambling the MOT object based on the generated control word, and requesting an entitlement control message (ECM) by transferring the generated control word; A qualification control message transmission step of the CA receiving and generating a credential control message including the control word and access authority information (Access Criteria) according to the credential control message request and transmitting the credential control message to the scrambler; A request value transfer step of the scrambler transferring the entitlement control message to the data encoder in synchronization with the MOT object on which the scrambling is performed; And And a control word updating step of updating the control word when a preset specific event occurs. The method of claim 7, wherein The preset specific event, And changing the MOT object and changing the access right information. A scrambling request reception step of receiving a scrambling request for a multimedia object transfer (MOT) object from a data encoder; A control word generation step of generating a control word according to the scrambling request; A scrambling step of scrambling the MOT object based on the control word; A qualification control message receiving step of transmitting the control word and receiving an entitlement control message (ECM) including the control word and access authority information (Access Criteria) from the CA; A request value transfer step of transmitting the entitlement control message to the data encoder in synchronization with the MOT object on which the scrambling is performed; And And a control word updating step of updating the control word when a preset specific event occurs. The method of claim 9, The preset specific event, And changing the MOT object and changing the access right information. 11. The method according to claim 9 or 10, The scrambling request receiving step, And receiving a scrambling request for the MOT object corresponding to a data body list included in a MOT data carousel. The method of claim 11, The control word generation step, And generating the control word at the initial reception of the data body list of the MOT data carousel. The method of claim 11, The control word update step, And newly generating the control word in response to occurrence of the preset event including a change of the data body list and a change of the access right information.

Images