JP2013258507A - Digital broadcast receiver, program of the same, and digital broadcast transmitter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a digital broadcast receiver which is capable of coping with a new conditional access system (CAS) and receiving ECM/EMM also from a transmission channel other than a broadcast wave, with a broadcast signal which does not affect reception by a conventional digital broadcast receiver.SOLUTION: A digital broadcast receiver 1B comprises: access control descriptor separation means 11B which separates an access control descriptor from a PMT and a CAT containing a CAS descriptor and the access control descriptor for identifying different CASs, the PMT and CAT having been separated by demultiplexing means 10, and extracts packet identification and transmission information representing the transmission channels of an ECM and an EMM described in the access control descriptor; channel switch reception means 17 which switches and receives the ECM and the EMM from a channel based on a transmission channel; and conditional access control means 13 which decodes a content with the ECM/EMM filtered by the packet identification.

Description

  The present invention relates to a digital broadcast receiving apparatus and its program for decrypting content encryption using a conditional access system suitable for the self-receiving apparatus when a plurality of conditional access systems in digital broadcasting are operated in parallel, The present invention relates to a digital broadcast transmission apparatus that encrypts the program.

  Currently, content protection in digital terrestrial broadcasting is realized using a conditional access system (CAS). In this limited reception system, functions related to content access control are mounted on an IC card (CAS card), which is a tamper-resistant module, and access is restricted by combining the IC card and a receiving device. Furthermore, as a new method for content protection, a limited reception method (hereinafter referred to as a new method) for decrypting (descrambling) content encryption by software control without using an IC card has been standardized. (See Non-Patent Document 1).

  Note that the conventional digital broadcast receiving apparatus does not support the new method because the descrambling is performed only with the IC card. On the other hand, since a digital broadcast receiving apparatus manufactured in the future corresponds to a new system, in terrestrial digital broadcasting, it is necessary to perform broadcasting corresponding to a plurality of limited reception systems.

As a technique for operating a plurality of conditional access systems in parallel, a technique called a simulcrypt system is known (see Patent Document 1 and Non-Patent Document 2).
This simultaneous cryptosystem is a technique of describing a plurality of conditional access system descriptors used in the conventional conditional access system in parallel in PMT (Program Map Table) and CAT (Conditional Access Table).

For example, a scramble key for encrypting content is encoded and encrypted into information called ECM (Entitlement Control Message) and transmitted together with broadcast content. This ECM has a different encoding format and encryption method for each conditional access system.
Therefore, when a plurality of different limited reception methods are adopted, a plurality of ECMs are transmitted in parallel.
In this case, in the simultaneous cryptosystem, a plurality of conditional access system descriptors for each conditional access system are written in parallel in the PMT, and the reception apparatus uses the conditional access system identifier described in the conditional access system descriptor to determine whether the local reception apparatus And the ECM is specified by the packet identification (PID) described in the conditional access system descriptor.

Further, for example, in the limited reception method, there is information called EMM (Entitlement Management Message) in order to individually transmit contract information and the like to the receiving device. This EMM also has a different encoding format and encryption method for each limited reception method, and when a plurality of different limited reception methods are adopted, a plurality of EMMs are transmitted in parallel.
In this case, in the simultaneous cryptosystem, a plurality of conditional access system descriptors for each conditional access system are written in parallel in the CAT, and the receiving apparatus uses the conditional access system identifier described in the conditional access system descriptor in accordance with the local reception apparatus. And the EMM is specified by the packet identification (PID) described in the conditional access system descriptor.

JP 2004-320113 A

“Access Control System Standards for Digital Broadcasting (ARIB STD-B25) Part 3”, version 6.0, revised by the Japan Radio Industry Association, March 28, 2011 "Digital Terrestrial Television Broadcasting Operation Regulations Technical Data (ARIB TR-B14) Volume 5 Part 2", 4.8 edition, P112-113, The Japan Radio Industry Association, revised on February 14, 2012

  When a plurality of conditional access system descriptors are written in parallel in the PMT or CAT by applying the above-described simultaneous cryptosystem, the digital broadcast receiving apparatus separates the conditional access system descriptor that matches the conditional access system of its own receiving apparatus. Thus, it is necessary to extract the PID.

However, since the conventional digital broadcast receiving apparatus is designed assuming a conditional access system using an IC card that is currently in operation, it is not necessarily compatible with its own receiver out of multiple conditional access system descriptors. There are many receiving apparatuses that are not designed to extract the PID by separating the conditional access system descriptor.
That is, in such a digital broadcast receiving apparatus, when a multiple cryptosystem is applied and a plurality of conditional access system descriptors are written in parallel in PMT or CAT, the conditional access system descriptors that are not compatible with the local reception apparatus are used. By extracting an incorrect PID, there is a problem that a correct scramble key cannot be extracted and video / audio cannot be normally reproduced.

  Moreover, since the conventional conditional access system descriptor is based on the premise that the ECM / EMM transmitted by the broadcast wave is specified, the ECM / EMM transmitted from a transmission path other than the broadcast wave is included in the descriptor. Cannot be specified. However, with the new conditional access system, there is a demand for transmitting ECM / EMM from other than broadcast waves.

  The present invention has been made in view of the above problems and demands, and is compatible with a new limited reception system by a broadcast signal that does not affect the reception of a conventional digital broadcast receiver, and other than broadcast waves. It is an object of the present invention to provide a digital broadcast receiving apparatus and its program capable of transmitting ECM / EMM and a digital broadcast transmitting apparatus.

  The present invention has been made to solve the above-mentioned problems. First, the digital broadcast transmitting apparatus according to claim 1 is configured to receive encrypted content transmitted via a broadcast wave by a conditional access system. The digital broadcast receiving apparatus for reproducing by the above-described configuration, comprising: a demultiplexing unit, an access control descriptor separating unit, a path switching receiving unit, a filtering unit, a limited reception control unit, and a descrambling unit .

  In such a configuration, the digital broadcast receiving apparatus uses a demultiplexing unit to describe a conditional access system descriptor and an access control descriptor, which are predetermined to identify different conditional access systems multiplexed on the broadcast wave. PMT and CAT, which are table information included in the area, ECM and EMM, which are a plurality of message information corresponding to the different conditional access methods, and encrypted content are separated.

Then, the digital broadcast receiving apparatus separates the access control descriptor from the table information separated by the demultiplexing means by the access control descriptor separating means, packet identification described in the access control descriptor, and ECM And transmission information indicating the transmission path of the EMM.
As a result, the digital broadcast receiver specifies a packet for transmitting an ECM / EMM corresponding to another conditional access method different from the conditional access method specified by the conventional conditional access method descriptor, and sets the transmission path. Can be identified.

Then, the digital broadcast receiving device is transmitted by the path switching receiving means via the broadcast wave separated by the demultiplexing means based on the transmission path specified by the transmission information extracted from the access control descriptor separating means. A plurality of ECMs and EMMs, or a single or a plurality of ECMs and EMMs transmitted from other transmission paths are switched and received.
Thereby, the digital broadcast receiving apparatus can receive ECM and EMM from paths other than broadcast waves.

Then, the digital broadcast receiving apparatus extracts the ECM and EMM corresponding to the packet identification extracted from the access control descriptor separating unit by the filtering unit from the plurality of ECMs and EMMs received by the path switching receiving unit.
As a result, the digital broadcast receiving apparatus can extract ECM and EMM corresponding to the limited reception method specified by the access control descriptor.

Then, the digital broadcast receiving apparatus generates a scramble key by the limited reception control unit by the limited reception method using the ECM and EMM extracted by the filtering unit.
Then, the digital broadcast receiving apparatus decrypts the content using the scramble key generated by the conditional access control means by the descrambling means.

  According to a second aspect of the present invention, there is provided the digital broadcast receiving apparatus according to the first aspect, wherein the PMT and the CAT have access to a predetermined conditional access system identifier that is different for each conditional access system. The control descriptor is included, the access control descriptor separating means further extracts the conditional access system identifier from the access control descriptor, and the conditional access control means outputs the conditional access system identifier for identifying its own conditional access system The apparatus further includes a comparison unit and a switching signal output unit.

  In such a configuration, the digital broadcast receiving apparatus compares the conditional access system identifier extracted by the access control descriptor separating unit with the conditional access system identifier output by the conditional access control unit by the comparison unit. Thereby, the digital broadcast receiving apparatus can determine whether the conditional access method performed by the conditional access control means matches the conditional access method specified by the conditional access method identifier.

The digital broadcast receiving apparatus outputs the ECM and EMM extracted by the filtering means to the limited reception control means when the switching signal output means determines that the identifiers match with each other.
As a result, only the ECM and EMM that match the conditional access method are processed by the conditional access control means.

  Furthermore, the digital broadcast receiving program according to claim 3 is a digital broadcast receiving apparatus for reproducing encrypted content transmitted via a broadcast wave by a limited reception method, wherein the computer is demultiplexing means, access control It is configured to function as a descriptor separation unit, a path switching reception unit, a filtering unit, a limited reception control unit, and a descrambling unit.

  In such a configuration, the digital broadcast receiving program uses the demultiplexing means to describe a conditional access system descriptor and an access control descriptor that are predetermined to identify different conditional access systems multiplexed on the broadcast wave. PMT and CAT, which are table information included in the area, ECM and EMM, which are a plurality of message information corresponding to the different conditional access methods, and encrypted content are separated.

  Then, the digital broadcast receiving program separates the access control descriptor from the table information separated by the demultiplexing means by the access control descriptor separating means, packet identification described in the access control descriptor, and ECM And transmission information indicating the transmission path of the EMM.

The digital broadcast receiving program is transmitted by the path switching receiving means via the broadcast wave separated by the demultiplexing means based on the transmission path specified by the transmission information extracted from the access control descriptor separating means. A plurality of ECMs and EMMs, or a single or a plurality of ECMs and EMMs transmitted from other transmission paths are switched and received.
Then, the digital broadcast receiving program extracts the ECM and EMM corresponding to the packet identification extracted from the access control descriptor separating unit by the filtering unit from the plurality of ECMs and EMMs received by the path switching receiving unit.

Then, the digital broadcast receiving program generates a scramble key by the limited reception control unit by the limited reception method using the ECM and EMM extracted by the filtering unit.
Then, the digital broadcast receiving program decrypts the content using the scramble key generated by the conditional access control means by the descrambling means.

  The digital broadcast transmission apparatus according to claim 4 is a digital broadcast transmission apparatus that encrypts content by a limited reception method and transmits the content via a broadcast wave, and includes a scramble unit, a first message information generation unit, The second message information generation unit, the transmission path switching unit, the descriptor generation unit, the table information generation unit, the multiplexing unit, and the communication transmission unit are provided.

In such a configuration, the digital broadcast transmitting apparatus encrypts the content with the scramble key by the scramble means.
The digital broadcast transmitting apparatus generates ECM and EMM corresponding to a predetermined first limited reception method by the first message information generation unit, and is different from the first limited reception method by the second message information generation unit. An ECM and an EMM corresponding to the second limited reception method are generated.

Then, the digital broadcast transmission apparatus switches the output destination of the transmission path according to an instruction from the outside with respect to the ECM and EMM generated by the second message information generation means by the transmission path switching means.
Then, the digital broadcast transmission device generates a conditional access method descriptor for identifying the first conditional access method and an access control descriptor for identifying the second conditional access method by the descriptor generating means, The transmission information indicating the transmission path is described in the access control descriptor.
Thereby, the digital broadcast receiving apparatus can specify the transmission source of the corresponding ECM and EMM by the transmission information of the access control descriptor.

Then, the digital broadcast transmitting apparatus generates table information in which the conditional access system descriptor and the access control descriptor generated by the descriptor generating unit are described in the descriptor area by the table information generating unit.
The digital broadcast transmitting apparatus broadcasts the output destination of the transmission path using the multiplexing means, the content encrypted by the scramble means, the ECM and EMM generated by the first message information generation means, and the transmission path switching means. The ECM and EMM generated by the second message information generation means and the table information generated by the table information generation means are multiplexed and broadcast.

  Further, the digital broadcast transmission device digitally broadcasts the ECM and EMM generated by the second message information generation unit when the communication transmission unit instructs the transmission path switching unit to communicate the output destination of the transmission path. Send to the receiving device.

The present invention has the following excellent effects.
According to the first, third, and fourth aspects of the present invention, a conventional conditional access system descriptor for identifying a conditional access system and an access control description for identifying other conditional access systems in PMT and CAT. By describing the child in parallel, it is possible to deal with a new limited reception system independently of the conventional limited reception system. At this time, since the conventional digital broadcast receiving apparatus refers to the conditional access system descriptor, reception of the conventional digital broadcast receiving apparatus is not affected.
Furthermore, according to the first aspect of the present invention, the ECM / EMM transmission path can be set to other than the broadcast wave. Therefore, according to the present invention, even when the corresponding limited reception method is increased, it is possible to suppress the compression of the broadcast band.

  According to the second aspect of the present invention, in addition to the effect of the first aspect, even when a plurality of new conditional access systems are adopted, an ECM corresponding to the conditional access system corresponding to each receiving apparatus. Since / EMM can be reliably extracted, the content can be reproduced correctly. In addition, since a plurality of conditional access systems can be controlled in this way, even if it is difficult to maintain the security of one conditional access system, damage can be minimized.

It is a schematic block diagram which shows the structure of the digital broadcasting system which concerns on embodiment of this invention. It is a block block diagram which shows the structure of the digital broadcast receiver which concerns on 1st Embodiment of this invention. It is a data block diagram of the descriptor for identifying a conditional access system, (a) is an access control descriptor, (b) is a data block diagram of a conditional access system descriptor. It is a flowchart which shows operation | movement of the access control descriptor isolation | separation means of the digital broadcast receiver which concerns on 1st Embodiment of this invention. It is a block block diagram which shows the structure of the digital broadcast receiver which concerns on 2nd Embodiment of this invention. It is a flowchart which shows operation | movement of the access control descriptor isolation | separation means of the digital broadcast receiver which concerns on 2nd Embodiment of this invention. It is a block block diagram which shows the structure of the digital broadcast receiver which concerns on 3rd Embodiment of this invention. It is a flowchart which shows operation | movement of the access control descriptor isolation | separation means of the digital broadcast receiver which concerns on 3rd Embodiment of this invention. It is a block block diagram which shows the structure of the digital broadcast receiver which concerns on 4th Embodiment of this invention. It is a flowchart which shows operation | movement of the access control descriptor isolation | separation means of the digital broadcast receiver which concerns on 4th Embodiment of this invention. It is a block block diagram which shows the structure of the digital broadcast transmitter which concerns on embodiment of this invention.

Embodiments of the present invention will be described below with reference to the drawings.
<Outline of digital broadcasting system>
First, an overview of a digital broadcasting system according to an embodiment of the present invention will be described with reference to FIG.

  The digital broadcast system S includes a digital broadcast transmission device 2 owned by a broadcaster and digital broadcast reception devices 1, 1, 1,... Installed in each home. This is a system in which content (video, audio, etc.) transmitted by a broadcast wave W is received by the digital broadcast receiver 1 and viewed by a viewer. The broadcast wave W may be wireless or wired, such as terrestrial digital broadcast, satellite broadcast, and cable broadcast.

In the digital broadcast system S, content is scrambled (encrypted) in the digital broadcast transmission device 2, and the scrambled content is descrambled (decrypted) in the digital broadcast reception device 1, so that the content is received by a limited reception method. To protect.
Hereinafter, the digital broadcast receiving device 1 and the digital broadcast transmitting device 2 constituting the digital broadcast system S will be described in order.

<First Embodiment>
[Configuration of digital broadcast receiver]
First, the configuration of the digital broadcast receiving apparatus 1 according to the first embodiment of the present invention will be described with reference to FIG.
The digital broadcast receiving apparatus 1 receives encrypted content transmitted from the digital broadcast transmitting apparatus 2 (see FIG. 1), and decrypts the encrypted content using a limited reception method. Here, the digital broadcast receiving apparatus 1 includes a channel selection / demodulation unit (not shown), a demultiplexing unit 10, an access control descriptor separation unit 11, a filtering unit 12, a conditional access control unit 13, a descrambling unit. Means 14.

The demultiplexing means 10 receives an MPEG-2 TS (transport stream) packet obtained by demodulating the broadcast signal selected by the viewer from the broadcast wave W received via the antenna by the channel selection / demodulation means (not shown). To separate.
The demultiplexing means 10 separates a PMT (Program Map Table) and a CAT (Conditional Access Table) that are multiplexed and transmitted in the TS, and outputs them to the access control descriptor separating means 11.
Further, the demultiplexing means 10 separates an ECM (Entitlement Control Message) and an EMM (Entitlement Management Message) that are multiplexed and transmitted in the TS, and outputs them to the filtering means 12.
Further, the demultiplexing means 10 separates the content (video / audio) which is a broadcast program multiplexed and transmitted on the TS, and outputs it to the descrambling means 14.

Here, the PMT is table information indicating stream (component) information of a broadcast program, packet identification (packet ID: PID) of a TS packet that transmits an ECM, and the like. The CAT is table information indicating packet identification of a TS packet that transmits an EMM.
The ECM is data that transmits information common to all receiving apparatuses, and is message information that mainly transmits scramble keys for scrambled broadcasts and broadcast program information. The EMM is data that transmits information unique to the receiving apparatus, and is message information that mainly transmits a work key for decrypting the ECM.

  The access control descriptor separating means 11 separates the access control descriptor from the PMT and CAT descriptor areas separated by the demultiplexing means 10 and extracts the packet identification described in the access control descriptor. It is. The access control descriptor is a descriptor for specifying another conditional access method different from the conditional access method specified by the conditional access method descriptor.

  That is, when a PMT is input, the access control descriptor separating unit 11 searches for an access control descriptor with a predetermined descriptor tag value from the descriptors described in the descriptor area of the PMT. Separate the corresponding access control descriptor. Then, the access control descriptor separating unit 11 extracts the PID (packet identification) described in the separated access control descriptor.

  Similarly, when the CAT is input, the access control descriptor separating unit 11 uses a predetermined descriptor tag value from the descriptors described in the CAT descriptor area. And the corresponding access control descriptor is separated. Then, the access control descriptor separating unit 11 extracts the PID (packet identification) described in the separated access control descriptor.

If the PID value is a value (0x1FFF) determined in advance as a null packet, the access control descriptor separating unit 11 ignores the access control descriptor and further describes it in the descriptor area. The access control descriptor is searched from the descriptors that have been set.
Then, the access control descriptor separating unit 11 outputs the extracted PID to the filtering unit 12.

  Here, the data structure of the access control descriptor will be described with reference to FIG. As shown in FIG. 3A, the access control descriptor includes a descriptor tag D1, a descriptor length D2, a conditional access method identifier D3, transmission information D4, a packet identification (PID) D5, and data D6. It consists of.

The descriptor tag D1 is an area in which a predetermined value for specifying the access control descriptor is described. The descriptor length D2 is an area describing the number of data bytes that follow. The conditional access system identifier D3 is an area describing a predetermined value for identifying the type of the conditional access system. The transmission information D4 is an area describing information indicating an ECM / EMM transmission path. The packet identification (PID) D5 is an area for describing the packet identification value of the TS packet. The data D6 is a spare data area, although not specified here.
Here, the conditional access system identifier D3 and the transmission information D4 are information that is referred to in the digital broadcast receivers in the second and subsequent embodiments.

FIG. 3B shows the data structure of a conventional conditional access system descriptor as a reference. Since this access control descriptor and the conditional access system descriptor have different values for the descriptor tags D1 and E1, both descriptors are described in parallel in the PMT and CAT descriptor areas. Can also distinguish each descriptor.
Returning to FIG. 2, the description of the configuration of the digital broadcast receiving apparatus 1 will be continued.

The filtering unit 12 extracts the ECM and EMM corresponding to the packet identification (PID) extracted from the access control descriptor separating unit 11 from the ECM and EMM separated by the demultiplexing unit 10.
That is, the filtering unit 12 functions as a PID filter that passes only TS packets having the same value as the PID described in the access control descriptor among the plurality of ECMs and EMMs separated by the demultiplexing unit 10.
The filtering unit 12 outputs the filtered ECM and EMM to the conditional access control unit 13.

The conditional access control means 13 generates a scramble key by the ECM and EMM extracted by the filtering means 12.
The conditional access control means 13 is a general CA module that generates a scramble key in accordance with the procedure of a conventional access control method defined in ARIB STD-B25. That is, the conditional access control means 13 generates a work key by decrypting the EMM with a device key or master key stored in advance in a storage means (not shown), and decrypts the ECM with the work key. Then, a scramble key is generated.
The limited reception control unit 13 outputs the generated scramble key Ks to the descrambling unit 14.

  The descrambling means 14 descrambles (decodes) the scrambled content (video / audio) TS packet separated by the demultiplexing means 10 with the scramble key generated by the limited reception control means 13. . The content decrypted by the descrambling means 14 is output to a display device or the like (not shown), decoded into data that can be viewed by the viewer, and displayed.

  By configuring the digital broadcast receiving apparatus 1 as described above, the digital broadcast receiving apparatus 1 can use the conventional limited reception scheme descriptor for identifying the limited reception scheme and other conditional access schemes in PMT and CAT. It is possible to separate the access control descriptor from the descriptor area in which the access control descriptor for identifying the ID is written in parallel and perform the limited reception process. At this time, since the conventional digital broadcast receiving apparatus ignores the access control descriptor and refers to the conditional access system descriptor, this is the case when another conditional access system is added by the access control descriptor. However, reception is not affected.

[Operation of digital broadcast receiver]
Next, the operation of the digital broadcast receiving apparatus 1 according to the first embodiment of the present invention will be described. The operation of descrambling the video / audio by the limited reception method in the digital broadcast receiving apparatus 1 is a general operation, and the description thereof is omitted here.
Hereinafter, referring to FIG. 4 (for the configuration, refer to FIG. 2 as appropriate), the access control descriptor specifying the conditional access system is separated from the PMT / CAT, which is the main operation of the present invention, and the ECM / The operation of the access control descriptor separating unit 11 that extracts the packet identification (PID) that specifies the EMM will be described in detail.

  First, the access control descriptor separating unit 11 sequentially extracts descriptors described in the descriptor area of each table information of PMT or CAT inputted after being separated by the demultiplexing unit 10 (step S1). Here, when the descriptors cannot be extracted, that is, when the extraction of all the descriptors is completed (NO in step S2), the access control descriptor separating unit 11 ends the operation.

  On the other hand, when the descriptor can be extracted (YES in step S2), the access control descriptor separating unit 11 determines that the value of the descriptor tag (D1: see FIG. 3A) of the descriptor is in advance. It is determined whether or not the descriptor is an access control descriptor depending on whether or not the tag value is the determined access control descriptor (step S3).

  Here, when the extracted descriptor extracted in step S1 is an access control descriptor (YES in step S3), the access control descriptor separating unit 11 uses the PID (packet identification) described in the access control descriptor. ) Is a value defined as a null packet (step S4). Note that since a TS packet with a PID of “0x1FFF” is preliminarily defined as a null packet in the TS, here, the access control descriptor separating unit 11 determines whether or not the PID is “0x1FFF”.

If the PID is not a value defined as a null packet (0x1FFF) (NO in step S4), the access control descriptor separating unit 11 outputs the PID to the filtering unit 12 (step S5).
On the other hand, if the descriptor extracted in step S1 is not an access control descriptor (NO in step S3), or if the PID described in the access control descriptor is “0x1FFF” (YES in step S4) ), The access control descriptor separating means 11 returns to step S1 and extracts the next descriptor.

  As described above, the access control descriptor separating unit 11 extracts the PID by separating the access control descriptor written in parallel with the conventional conditional access system descriptor in the PMT / CAT descriptor area. As a result, the digital broadcast receiving apparatus 1 can operate in a new conditional access system that is different from the conventional conditional access system due to descriptors that are not accessed by the existing digital broadcast receiving apparatus.

Second Embodiment
[Configuration of digital broadcast receiver]
Next, the configuration of a digital broadcast receiving device 1A according to the second embodiment of the present invention will be described with reference to FIG.
The digital broadcast receiving apparatus 1A receives the scrambled content transmitted from the digital broadcast transmitting apparatus 2 (see FIG. 1), and decrypts the encryption of the content by a limited reception method (see FIG. 2). ), And a function for identifying different conditional access systems with the same access control descriptor.
That is, the digital broadcast receiving apparatus 1A operates with an access control descriptor corresponding to the limited reception system of the own receiving apparatus, when a plurality of access control descriptors are transmitted by applying the simulcrypt system. It has a function.

Here, the digital broadcast receiving apparatus 1A includes a channel selection / demodulation unit (not shown), a demultiplexing unit 10, an access control descriptor separating unit 11A, a filtering unit 12, a conditional access control unit 13A, a descrambling unit. Means 14, comparison means 15, and switching signal output means 16 are provided.
Here, the demultiplexing means 10, the filtering means 12, and the descrambling means 14 have the same configuration as the digital broadcast receiving apparatus 1 described in FIG.

  The access control descriptor separating unit 11A separates the access control descriptor from the PMT and CAT separated by the demultiplexing unit 10 and extracts the packet identification described in the access control descriptor, The access control descriptor separating unit 11 described with reference to FIG. 2 has the same function. Further, the access control descriptor separating unit 11A has a function of extracting a conditional access method identifier described in the access control descriptor from a plurality of access control descriptors.

Here, the conditional access method identifier is data (the limited reception method identifier D3) in the configuration of the access control descriptor described in FIG. 3A, and a predetermined value is set for each different conditional access method. The
Here, the access control descriptor separating unit 11A outputs the extracted packet identification (PID) to the filtering unit 12, and outputs the extracted limited reception method identifier (CA_system_ID) to the comparing unit 15.

  The access control descriptor separating unit 11A receives a signal (ON) from the comparing unit 15 that the conditional access method specified by the conditional access method identifier (CA_system_ID) is compatible with its own receiving device. Ends the search for descriptors. As a result, it is possible to prevent the subsequent unnecessary search operation from being executed.

  The conditional access control means 13A generates a scramble key by the ECM and EMM extracted by the filtering means 12, and has the same function as the conditional access control means 13 described in FIG. It should be noted that only the information that is permitted to be output by the switching signal output means 16 among the ECM and EMM extracted by the filtering means 12 is input to the limited reception control means 13A.

  Further, the conditional access control means 13A has a function of outputting a conditional access system identifier (CA_system_ID), which is a predetermined value for identifying the conditional access system performed by the receiving apparatus. The conditional access control unit 13A outputs the conditional access system identifier (CA_system_ID) to the comparison unit 15.

The comparison unit 15 compares the conditional access system identifier (CA_system_ID) extracted by the access control descriptor separating unit 11A with the limited reception system identifier (CA_system_ID) output by the conditional access control unit 13A.
When the values of both identifiers match, this comparing means 15 is a signal (ON) indicating that the conditional access system specified by the conditional access system identifier extracted by the access control descriptor separating means 11A is compatible with its own receiver. Is output to the access control descriptor separating unit 11A and the switching signal output unit 16. When both identifiers do not match, the comparison unit 15 outputs a signal (OFF) indicating that they do not match to the access control descriptor separation unit 11A and the switching signal output unit 16.

The switching signal output means 16 determines that the conditional access system identifier (CA_system_ID) extracted by the access control descriptor separating means 11A matches the conditional access system identifier (CA_system_ID) output by the conditional access control means 13A by the comparison means 15. When the determination is made, the ECM and EMM extracted by the filtering unit 12 are output to the conditional access control unit 13A.
Here, the switching signal output means 16 outputs ECM / EMM to the conditional access control means 13A when an ON signal is input from the comparison means 15, and does not output when an OFF signal is input. I will do it.

By configuring the digital broadcast receiving device 1A as described above, the digital broadcast receiving device 1A is a case where a plurality of new limited reception methods are adopted in addition to the effects of the digital broadcast receiving device 1 (see FIG. 2). However, since the ECM / EMM corresponding to the limited reception method corresponding to each receiving device can be reliably extracted, the content can be correctly reproduced.
Furthermore, since it is possible to control a plurality of conditional access systems, it is possible to minimize damage even if it is difficult to maintain the security of the single conditional access system.

[Operation of digital broadcast receiver]
Next, the operation of the digital broadcast receiving apparatus 1A according to the second embodiment of the present invention will be described. The operation of descrambling the video / audio by the limited reception method in the digital broadcast receiving apparatus 1A is a general operation, and thus the description thereof is omitted here.

  Hereinafter, referring to FIG. 6 (for the configuration, refer to FIG. 5 as appropriate), from the PMT / CAT, which is the main operation of the present invention, from a plurality of access control descriptors that specify the limited reception method, ECM / EMM The operation of the access control descriptor separating unit 11A for extracting the packet identification (PID) for specifying the ID will be described in detail. Steps S1, S2, S3, and S4 are the same as the operation of the access control descriptor separating unit 11 (see FIG. 2) of the digital broadcast receiving apparatus 1 described in FIG.

  If the descriptor can be extracted in step S2 (YES in step S2), the access control descriptor separating unit 11A determines whether or not the output of the comparing unit 15 is ON (step S2A). Here, when the output of the comparison unit 15 is ON (YES in step S2A), the access control descriptor separation unit 11A ends the operation. This is because the conditional access system identifier (CA_system_ID) extracted by the access control descriptor separating unit 11A in the previous loop processing and the conditional access system identifier (CA_system_ID) output by the conditional access control unit 13A match. This is because it is not necessary to extract descriptors thereafter.

  On the other hand, when the output of the comparison unit 15 is OFF (NO in step S2A), the access control descriptor separation unit 11A determines that the extracted descriptor is an access control descriptor (YES in step S3), and the access control is performed. When the value of PID (packet identification) described in the descriptor is not the null packet value (0x1FFF) (NO in step S4), the conditional access system identifier (CA_system_ID) described in the access control descriptor is set. While outputting to the comparison means 15, it outputs PID to the filtering means 12 (step S5A).

  As described above, the access control descriptor separating unit 11A separates a plurality of access control descriptors described in parallel with the conventional conditional access system descriptor in the PMT / CAT descriptor area, and obtains the PID. Extract. At this time, the access control descriptor separating unit 11A outputs a conditional access system identifier (CA_system_ID) that identifies the conditional access system.

  As a result, the digital broadcast receiving apparatus 1A can use the limited reception of its own receiving apparatus by the access control descriptor suitable for the limited reception method applicable to the limited reception control means 13A even when there are a plurality of access control descriptors. It can operate reliably in the system.

<Third Embodiment>
[Configuration of digital broadcast receiver]
Next, with reference to FIG. 7, the structure of the digital broadcast receiver 1B which concerns on 3rd Embodiment of this invention is demonstrated.
The digital broadcast receiving apparatus 1B receives the scrambled content transmitted from the digital broadcast transmitting apparatus 2 (see FIG. 1), and decrypts the encryption of the content by a limited reception method (see FIG. 2). ) And a function capable of acquiring from various transmission paths without limiting the transmission path for acquiring ECM / EMM to only broadcast waves.

Here, the digital broadcast receiving apparatus 1B includes a channel selection / demodulation unit (not shown), a demultiplexing unit 10, an access control descriptor separating unit 11B, a filtering unit 12, a conditional access control unit 13, a descrambling unit. Means 14 and path switching receiving means 17 are provided.
Here, since the configuration other than the access control descriptor separating unit 11B and the path switching receiving unit 17 is the same as the configuration of the digital broadcast receiving apparatus 1 described in FIG.

  The access control descriptor separating unit 11B separates the access control descriptor from the PMT and CAT separated by the demultiplexing unit 10 and extracts the packet identification described in the access control descriptor, The access control descriptor separating unit 11 described with reference to FIG. 2 has the same function. Further, the access control descriptor separating unit 11B has a function of extracting a transmission path described in the access control descriptor.

Here, the transmission path is information specified by the data (transmission information D4) in the configuration of the access control descriptor described in FIG. 3A, and which transmission path the ECM / EMM is transmitted through. It is information that specifies. Here, the route is specified by a 3-bit value.
For example, when the bit value is “111” in binary notation, the transmission information D4 indicates that the transmission path is a broadcast wave. Further, other transmission paths such as communication are specified by other bit values.
Here, the access control descriptor separating unit 11B outputs the extracted packet identification (PID) to the filtering unit 12 and outputs the extracted transmission path (transmission information) to the path switching receiving unit 17.

The path switching receiving unit 17 includes a plurality of ECMs and EMMs transmitted via the broadcast wave separated by the demultiplexing unit 10 based on the transmission path (transmission information) extracted from the access control descriptor separating unit 11B. Alternatively, a single or a plurality of ECMs and EMMs transmitted from other transmission paths are switched and received.
In FIG. 7, the path switching receiving means 17 has an alternative configuration, but here, since the transmission path information is 3 bits, a maximum of 8 paths can be selected.

  When the transmission path is “111” in binary notation, the path switching receiving unit 17 acquires ECM / EMM from the demultiplexing unit 10 and outputs the ECM / EMM to the filtering unit 12. When the transmission path is other than “111” in binary notation, the path switching receiving unit 17 acquires ECM / EMM from a predetermined acquisition source according to the value and outputs the ECM / EMM to the filtering unit 12.

  By configuring the digital broadcast receiving device 1B as described above, the digital broadcast receiving device 1B can acquire ECM / EMM from other than broadcast waves in addition to the effects of the digital broadcast receiving device 1 (see FIG. 2). it can.

[Operation of digital broadcast receiver]
Next, the operation of the digital broadcast receiving device 1B according to the third embodiment of the present invention will be described. The operation of descrambling the video / audio by the limited reception method in the digital broadcast receiving apparatus 1B is a general operation, and thus the description thereof is omitted here.

  Hereinafter, the operation of the access control descriptor separating unit 11B, which is the main operation of the present invention, will be described with reference to FIG. 8 (refer to FIG. 7 as appropriate for the configuration). Steps S1 to S4 are the same as the operation of the access control descriptor separating unit 11 (see FIG. 2) of the digital broadcast receiving apparatus 1 described with reference to FIG. 4, and therefore only the differences will be described here.

  The difference from the operation of the access control descriptor separating unit 11 (see FIG. 2) is described in the access control descriptor extracted by the access control descriptor separating unit 11B in step S1 after the operations of steps S1 to S4. The PID is output to the filtering unit 12, and the transmission path (transmission information) described in the access control descriptor is output to the path switching reception unit 17 (step S5B).

  As described above, the access control descriptor separating unit 11B extracts the PID by separating the access control descriptor described in parallel with the conventional conditional access system descriptor in the PMT / CAT descriptor area. In addition, the ECM / EMM transmission path can be extracted. As a result, the digital broadcast receiving apparatus 1B can operate in a new conditional access system that is different from the conventional conditional access system due to a descriptor that is not accessed by the existing digital broadcast receiving apparatus. Furthermore, the digital broadcast receiving apparatus 1B can acquire ECM / EMM from other than broadcast waves, and can suppress the compression of the broadcast band.

<Fourth embodiment>
[Configuration of digital broadcast receiver]
Next, with reference to FIG. 9, the structure of 1 C of digital broadcast receivers which concern on 4th Embodiment of this invention is demonstrated.
This digital broadcast receiving device 1C receives the scrambled content transmitted from the digital broadcast transmitting device 2 (see FIG. 1) in the same manner as the digital broadcast receiving device 1B (see FIG. 7). And a function capable of acquiring from various transmission paths without limiting the transmission path for acquiring ECM / EMM to only broadcast waves, and with the same access control descriptor. A function for identifying different conditional access systems is provided.
That is, when a plurality of access control descriptors are transmitted by applying the simulcrypt system, the digital broadcast receiving apparatus 1C operates from among the access control descriptors corresponding to the limited reception system of the own receiving apparatus. It has a function.

  Here, the digital broadcast receiving apparatus 1C includes a channel selection / demodulation unit (not shown), a demultiplexing unit 10, an access control descriptor separating unit 11C, a filtering unit 12, a conditional access control unit 13A, a descrambling unit. Means 14, comparison means 15, switching signal output means 16, and path switching receiving means 17 are provided.

  Here, the demultiplexing means 10, the filtering means 12 and the descrambling means 14 have the same configuration as the digital broadcast receiving apparatus 1 described in FIG. 2, and the limited reception control means 13A, the comparison means 15 and the switching signal output means 16 are 5 has the same configuration as the digital broadcast receiving device 1A described in FIG. 5, and the path switching receiving means 17 has the same configuration as the digital broadcast receiving device 1B described in FIG. Omitted.

  The access control descriptor separating unit 11C separates the access control descriptor from the PMT and CAT separated by the demultiplexing unit 10, extracts the packet identification described in the access control descriptor, and also accesses the access control description. The transmission path described in the child is extracted and has the same function as the access control descriptor separating unit 11B described in FIG. Further, the access control descriptor separation unit 11C is the same as the access control descriptor separation unit 11A described with reference to FIG. 5 that extracts the conditional access method identifier described in the access control descriptor from a plurality of access control descriptors. It has a function.

  By configuring the digital broadcast receiving device 1C as described above, the digital broadcast receiving device 1C also has the effects of the digital broadcast receiving devices 1, 1A, 1B (see FIGS. 2, 5, and 7). become.

[Operation of digital broadcast receiver]
Next, the operation of the digital broadcast receiving device 1C according to the fourth embodiment of the present invention will be described. Note that the operation of descrambling the video / audio by the limited reception method in the digital broadcast receiving apparatus 1C is a general one, and the description thereof is omitted here.

  The operation of the access control descriptor separating unit 11C, which is the main operation of the present invention, will be described below with reference to FIG. 10 (refer to FIG. 9 as appropriate for the configuration). Steps S1 to S4 are the same as the operation of the access control descriptor separating unit 11A (see FIG. 5) of the digital broadcast receiving apparatus 1A described with reference to FIG. 6, and therefore only the differences will be described here.

  The difference from the operation of the access control descriptor separating unit 11A (see FIG. 5) is described in the access control descriptor extracted by the access control descriptor separating unit 11C in step S1 after the operations of steps S1 to S4. The PID is output to the filtering unit 12 and the transmission path (transmission information) described in the access control descriptor is output to the path switching receiving unit 17 (step S5C).

  As described above, the access control descriptor separating unit 11C extracts the PID by separating the access control descriptor described in parallel with the conventional conditional access system descriptor in the PMT / CAT descriptor area. The conditional access system identifier (CA_system_ID) that specifies the ECM / EMM transmission path and the conditional access system can be extracted.

  As a result, the digital broadcast receiving apparatus 1C can operate in a new conditional access system that is different from the conventional conditional access system due to a descriptor that is not accessed by the existing digital broadcast receiving apparatus. Further, the digital broadcast receiving apparatus 1C uses the limited reception scheme of its own receiving apparatus by the access control descriptor suitable for the limited reception scheme to which the limited reception control means 13A can be applied even when there are a plurality of access control descriptors. Can work reliably. Furthermore, the digital broadcast receiving apparatus 1C can acquire ECM / EMM from other than broadcast waves, and can suppress the compression of the broadcast band.

While various embodiments of the present invention have been described above, the digital broadcast receivers 1, 1A, 1B, and 1C can be operated by a digital broadcast reception program that causes a general computer to function as each of the means described above.
The digital broadcast receiving program can be distributed via a network, or can be distributed by writing on a recording medium such as a CD-ROM. The digital broadcast receiving program can be operated on a personal computer, for example.

[Digital broadcasting transmitter]
Finally, the digital broadcast transmission device 2 will be described with reference to FIG.
The digital broadcast transmission apparatus 2 encrypts (scrambles) the content and transmits the encrypted content to the digital broadcast reception apparatuses 1, 1A, 1B, and 1C by a plurality of limited reception methods.
Here, the digital broadcast transmitting apparatus 2 includes a scramble unit 20, a first ECM / EMM generation unit 21, a second ECM / EMM generation unit 22, a transmission path switching unit 23, a descriptor generation unit 24, a PMT / CAT. A generation unit 25, a communication transmission unit 26, and a multiplexing unit 27 are provided.

  The scramble means 20 scrambles (encrypts) input content (video, audio, etc.) with a scramble key. The scramble means 20 may be encrypted by using an encryption algorithm predetermined by a limited reception method, for example, a MULTI2 cipher. The scramble unit 20 outputs the scrambled content to the multiplexing unit 27.

The first ECM / EMM generating means (first message information generating means) 21 generates an ECM (common information) by encrypting the scramble key used for scrambling by the scramble means 20 using the work key, and also generates a work key. Is encrypted with a device key or master key unique to the digital broadcast receiving apparatus to generate EMM (individual information).
The first ECM / EMM generation unit 21 generates a unique ECM / EMM by the limited reception method specified by the limited reception method descriptor. For example, the first ECM / EMM generation unit 21 generates an ECM / EMM corresponding to a limited reception method (B-CAS method or the like) using an IC card.
The first ECM / EMM generation means 21 outputs the generated ECM and EMM to the multiplexing means 27.

  Similar to the first ECM / EMM generation means 21, the second ECM / EMM generation means (second message information generation means) 22 encrypts the scramble key used for the scramble by the scramble means 20, using the work key, and the ECM. (Common information) is generated, and the work key is encrypted with a device key or master key unique to the digital broadcast receiving apparatus to generate EMM (individual information).

However, the second ECM / EMM generation means 22 generates a unique ECM / EMM with an access control descriptor that identifies another conditional access system different from the conditional access system descriptor. For example, the second ECM / EMM generation unit 22 uses the ECM / EMM corresponding to the limited reception method defined in the third part of the ARIB STD-B25 that decrypts the encryption of the content by software control without using the IC card. Generate.
The second ECM / EMM generation means 22 outputs the generated ECM and EMM to the transmission path switching means 23.

The transmission path switching unit 23 switches the output destination of the ECM and EMM input from the second ECM / EMM generation unit 22 to the multiplexing unit 27 or the communication transmission unit 26 based on a transmission path instructed from the outside.
In this transmission path switching means 23, by switching the output destination, the ECM and EMM generated by the second ECM / EMM generating means 22 are transmitted by broadcast waves via the multiplexing means 27, or via the communication transmitting means 26. Are switched over by the communication line.

The descriptor generation unit 24 generates a descriptor to be set in the PMT or CAT descriptor area. Here, the descriptor generation unit 24 generates each descriptor by inputting information for generating a conditional access method descriptor and an access control descriptor from the outside.
That is, the descriptor generation unit 24 uses a unique conditional access method identifier or a TS packet when transmitting the ECM / EMM generated by the first ECM / EMM generation unit 21 as information for generating the conditional access method descriptor. When the packet identification (PID) is input, a conditional access system descriptor is generated with a configuration as shown in FIG.

The descriptor generation unit 24 transmits a unique conditional access system identifier, transmission information indicating a transmission path, and ECM / EMM generated by the second ECM / EMM generation unit 22 as information for generating an access control descriptor. When the packet identification (PID) of the TS packet is input, an access control descriptor is generated with a configuration as shown in FIG.
The descriptor generation unit 24 outputs the generated descriptor to the PMT / CAT generation unit 25.

The PMT / CAT generation means (table information generation means) 25 generates PMT and CAT which are table information multiplexed on the TS.
The PMT / CAT generation unit 25 describes the descriptors (conditional reception method descriptor, access control descriptor, etc.) generated by the descriptor generation unit 24 in the descriptor area, and generates PMT and CAT. Note that the descriptor described in the PMT / CAT is a general descriptor other than the access control descriptor, and the data structure thereof is also known, so the description thereof is omitted here.
The PMT / CAT generation unit 25 outputs the generated PMT / CAT to the multiplexing unit 27.

  The communication transmission unit 26 transmits the ECM / EMM whose output destination has been switched as a communication line in the transmission path switching unit 23 to the digital broadcast receiving apparatus via the communication line. Thereby, it is possible to suppress the compression of the broadcast band when the ECM / EMM is transmitted by the broadcast wave.

The multiplexing means 27 uses the ECM / EMM generated by the first ECM / EMM generating means 21 and the second ECM / EMM generating means 21 when the transmission path is designated by a broadcast wave in the content scrambled by the scramble means 20. The generated ECM / EMM and the PMT / CAT generated by the PMT / CAT generating means 25 are multiplexed.
The multiplexing unit 27 transmits the multiplexed TS as a broadcast wave to the digital broadcast receiving device via a transmission modulation device (not shown).

By configuring the digital broadcast transmission device 2 as described above, the digital broadcast transmission device 2 can generate an ECM / EMM for each different limited reception method and transmit the ECM / EMM to the digital broadcast reception device. The reception method can be operated.
At this time, the digital broadcast transmitting apparatus 2 transmits the conventional conditional access system descriptor in the conventional format and writes the access control descriptor in the descriptor area in parallel with the conditional access system descriptor. It is possible to control a digital broadcast receiving apparatus to which a limited reception system is applied with an access control descriptor that is not recognized by a conventional digital broadcast receiving apparatus.

  Here, the digital broadcast transmitting apparatus 2 transmits the ECM and EMM to the digital broadcast receiving apparatus. However, the work key is set in advance in the limited reception control means 13 and 13A of the digital broadcast receiving apparatus. In the case of shipping, the PMT / CAT generation unit 25 may generate only the PMT. Moreover, the 1st ECM / EMM production | generation means 21 and the 2nd ECM / EMM production | generation means 22 should just produce | generate only ECM.

DESCRIPTION OF SYMBOLS S Digital broadcast system 1 Digital broadcast receiver 10 Demultiplexing means 11 Access control descriptor separation means 12 Filtering means 13 Limited reception control means 14 Descramble means 15 Comparison means 16 Switching signal output means 17 Path switching reception means 2 Digital broadcast transmission apparatus 20 scramble means 21 first ECM / EMM generation means (first message information generation means)
22 Second ECM / EMM generation means (second message information generation means)
23 Route switching means 24 Descriptor generating means 25 PMT / CAT generating means (table information generating means)
26 Communication transmission means

Claims (4)

A digital broadcast receiver for reproducing encrypted content transmitted via a broadcast wave by a limited reception method,
PMT and CAT, which are table information including a predetermined conditional access system descriptor and an access control descriptor that are set in advance in order to identify different conditional access systems, and a plurality of messages corresponding to the different conditional access systems Demultiplexing means for separating the broadcast wave in which at least ECM and EMM as information and the encrypted content are multiplexed;
Access for separating the access control descriptor from the table information separated by the demultiplexing means, and extracting packet identification described in the access control descriptor and transmission information indicating the transmission path of the ECM and EMM Control descriptor separation means;
Based on the transmission path specified by the transmission information extracted from the access control descriptor separation means, a plurality of ECMs and EMMs transmitted through the broadcast wave separated by the demultiplexing means, or other transmissions Path switching receiving means for switching and receiving single or plural ECMs and EMMs transmitted from the path;
Filtering means for extracting ECM and EMM corresponding to the packet identification extracted from the access control descriptor separating means from the plurality of ECMs and EMMs received by the path switching receiving means;
Conditional access control means for generating a scramble key by the ECM and EMM extracted by the filtering means;
A descrambling means for decrypting the content using the scramble key generated by the conditional access control means;
A digital broadcast receiving apparatus comprising: The PMT and CAT include an access control descriptor in which a predetermined conditional access system identifier that is different for each conditional access system is described,
The access control descriptor separating means further extracts the conditional access system identifier from the access control descriptor;
The conditional access control means outputs a conditional access method identifier for identifying its own conditional access method,
Comparing means for comparing the conditional access system identifier extracted by the access control descriptor separating means with the conditional access system identifier output by the conditional access control means;
A switching signal output means for outputting the ECM and EMM extracted by the filtering means to the conditional access control means when it is determined by the comparison means that both identifiers match;
The digital broadcast receiving apparatus according to claim 1, further comprising: In a digital broadcast receiving apparatus that reproduces encrypted content transmitted via a broadcast wave by a limited reception method,
PMT and CAT, which are table information including a predetermined conditional access system descriptor and an access control descriptor that are set in advance in order to identify different conditional access systems, and a plurality of messages corresponding to the different conditional access systems Demultiplexing means for separating the broadcast wave in which at least ECM and EMM as information and the encrypted content are multiplexed;
Access for separating the access control descriptor from the table information separated by the demultiplexing means, and extracting packet identification described in the access control descriptor and transmission information indicating the transmission path of the ECM and EMM Control descriptor separation means,
Based on the transmission path specified by the transmission information extracted from the access control descriptor separation means, a plurality of ECMs and EMMs transmitted through the broadcast wave separated by the demultiplexing means, or other transmissions Path switching receiving means for switching and receiving single or plural ECMs and EMMs transmitted from the path;
Filtering means for extracting ECM and EMM corresponding to the packet identification extracted from the access control descriptor separating means from a plurality of ECMs and EMMs received by the path switching receiving means;
Conditional access control means for generating a scramble key by the ECM and EMM extracted by the filtering means,
Descrambling means for decrypting the content using the scramble key generated by the conditional access control means;
Digital broadcast reception program to function as A digital broadcast transmission device that encrypts content by a limited reception method and transmits the content via broadcast waves,
A scramble means for encrypting the content with a scramble key;
First message information generating means for generating an ECM and an EMM corresponding to a predetermined first limited reception method;
Second message information generating means for generating an ECM and an EMM corresponding to a second conditional access system different from the first conditional access system;
Transmission path switching means for switching the output destination of the transmission path in response to an instruction from the outside for the ECM and EMM generated by the second message information generation means,
Generating a conditional access system descriptor for identifying the first conditional access system and an access control descriptor for identifying the second conditional access system, and transmitting transmission information indicating the transmission path to the access control description Descriptor generation means described in the child;
Table information generating means for generating table information in which the conditional access system descriptor and access control descriptor generated by the descriptor generating means are described in the descriptor area;
The content encrypted by the scramble means, the ECM and EMM generated by the first message information generating means, and the second when the output destination of the transmission path is designated as a broadcast wave by the transmission path switching means Multiplexing means for multiplexing and broadcasting the ECM and EMM generated by the message information generating means and the table information generated by the table information generating means;
Communication transmitting means for transmitting the ECM and EMM generated by the second message information generating means when the transmission path switching means is instructed to communicate the output destination of the transmission path to the digital broadcast receiving apparatus by communication;
A digital broadcast transmitting apparatus comprising:

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