JP5688658B2 - Broadcast wave encryption monitoring device - Google Patents

Description

  The present invention relates to a broadcast wave encryption monitoring apparatus, and more particularly, to an improvement in the identification of a cause device when a broadcast failure occurs.

  Terrestrial digital broadcasting is a method of transmitting and receiving video and audio as digital data, and is performed based on operational rules included in technical data (ARIB TR-B14, etc.) formulated by the Japan Radio Industry Association. Specifically, in order to prevent unauthorized copying of program content consisting of video and audio, as shown in FIG. 4, B-CAS (BS-Conditional Access Systems) provided by BS Conditional Access Systems, Inc. ) The data is transmitted after being scrambled (hereinafter also referred to as encryption) by a limited reception method using a card.

  In FIG. 4, the program content consisting of video / audio is encoded by the MPEG encoder 1 and then input to the video / audio scrambler 2 and encrypted with the encryption key Ks. The program content composed of video / audio encrypted by the video / audio scrambler 2 is input to the multiplexer 3.

  On the other hand, the encryption key Ks is input to the Ks scrambler 4 which performs encryption by the “B-CAS” method, and is encrypted. The encrypted encryption key Ks ′ is also input to the multiplexer 3.

  The multiplexer 3 multiplexes the output data of the video / audio scrambler 2 and the output data of the Ks scrambler 4 as one transport stream TS.

  The transport stream TS multiplexed by the multiplexer 3 is input to the modulation / transmitter 5 and modulated, and then power-amplified as a transmission signal of terrestrial digital broadcasting and transmitted via the antenna 6.

  When viewing terrestrial digital broadcasts encrypted with the “B-CAS” method shown in FIG. 4, a “B-CAS card” with a relatively large credit card size, to which a unique attribute is assigned for each receiver, is used. Inserted into each receiver, decrypts Ks from Ks ′ using the encryption key stored in the “B-CAS card”, and further decrypts each packet with the video / audio decoder using Ks.

  On the other hand, a broadcasting station for digital terrestrial broadcasting monitors whether or not program content is correctly scrambled by a broadcast wave encryption monitoring device having a configuration as shown in FIG.

  In FIG. 5, the packet of the transport stream TS is input to the packet discriminator 7, and an ECM (Packetized Elementary Stream (PES) packet including encrypted video / audio and an encrypted encryption key Ks ′ is included). Entitlement Control Message) packet.

  The ECM packet discriminated by the packet discriminator 7 is input to the “B-CAS” type Ks decoder 8, and the PES packet is input to the PES packet decoder 9. The PES packet decryptor 9 decrypts the PES packet based on the encryption key Ks decrypted by the Ks decryptor 8.

  The PES packet decoded by the PES packet decoder 9 is input to the MPEG decoder 10, and the video / audio of the program content that has been encoded is restored and reproduced.

  The monitoring operator of the broadcast station monitors the presence / absence of a broadcast failure based on the video / audio status of the program content restored and output from the MPEG decoder 10.

  By the way, the “B-CAS” method that has been operated conventionally has a cost in issuing and managing the “B-CAS card” necessary for descrambling.

  In addition, in order to incorporate digital terrestrial broadcast reception functions into mobile devices such as in-vehicle devices and mobile phones, it is necessary to secure a space for mounting “B-CAS card” devices, and to reduce the size of mobile devices. It is difficult.

  Therefore, in recent years, in order to solve the problems caused by such “B-CAS card” of credit card size, mini-size “B-CAS card” of the same size as SIM card has been put into practical use, “New RMP (Rights Management and Protection)” has also been developed as a limited reception method that uses the receiver's dedicated software to release scrambled terrestrial digital broadcasting without using a “B-CAS card”.

  Even if terrestrial digital broadcasting broadcast stations scramble and transmit program content using the "new RMP" method, the terrestrial digital broadcast station is encrypted using the B-CAS method that has been used since the beginning of terrestrial digital broadcasting. Existing viewers who have a receiving facility that can only view digital broadcasts will continue to transmit digital terrestrial broadcast signals encrypted using the B-CAS method so that program content can be viewed as before.

  FIG. 6 is a block diagram showing a connection example of a broadcast wave encryption monitoring apparatus in a conventional broadcasting system, and the same reference numerals are given to the parts common to FIGS. This broadcast wave encryption monitoring device is a broadcasting station for digital terrestrial broadcasting that encrypts the encryption key Ks used for the encryption processing of program content in parallel with the “B-CAS” method and the “new RMP” method. Used.

  In FIG. 6, the program content composed of video / audio is encoded by the MPEG encoder 1, input to the video / audio scrambler 2, encrypted with the encryption key Ks, and encrypted with the video / audio scrambler 2. The program content made up of the video / audio is input to the multiplexer 3.

  The encryption key Ks is input to the first Ks scrambler 4 that performs encryption by the “B-CAS” method, encrypted as the encryption key Ks′A, further converted into an ECM packet, and input to the multiplexer 3. It is also input to the second Ks scrambler 11 that performs encryption by the “new RMP” method, encrypted as the encryption key Ks′B, further converted into an ECM packet, and input to the multiplexer 3.

  The multiplexer 3 multiplexes the output data of the video / audio scrambler 2, the output data of the Ks scrambler 4, and the output data of the Ks scrambler 11 as one transport stream TS.

  The transport stream TS multiplexed by the multiplexer 3 is input to the modulation / transmitter 5 and modulated, and then power-amplified as a transmission signal of terrestrial digital broadcasting and transmitted via the antenna 6.

  The packet of the transport stream TS multiplexed by the multiplexer 3 is also input to the packet discriminator 7, and the first ECM packet including the encrypted encryption key Ks'A and the encrypted video / audio. And a second ECM packet including the encrypted encryption key Ks′B.

  The first ECM packet discriminated by the packet discriminator 7 is input to the “B-CAS” type Ks decoder 8 to decrypt the encryption key KsA, and the second ECM packet is the “new RMP” type Ks decryption. The encryption key KsB is decrypted by being input to the device 12. The PES packet is input to the PES packet decoders 9 and 13.

  The PES packet decryptor 9 decrypts the PES packet based on the encryption key KsA decrypted by the Ks decryptor 8, and the PES packet decryptor 13 decrypts the PES packet based on the encryption key KsB decrypted by the Ks decryptor 12. To do.

  The PES packet decoded by the PES packet decoder 9 is input to the MPEG decoder 10 and the video / audio of the program content encoded is restored and reproduced. The PES packet decoded by the PES packet decoder 13 is converted to the MPEG decoder 14. The video / audio of the program content that has been input and encoded is restored and reproduced.

  Based on the video / audio status of each program content restored and output from the MPEG decoders 10 and 14, the broadcast station monitoring operator can detect broadcast failures in the “B-CAS” system and “New RMP” system. You can monitor the occurrence.

  Patent Document 1 describes a technique related to digital broadcasting encrypted by the B-CAS method.

Japanese Patent No. 3103617

  However, according to the configuration of FIG. 6, the monitoring operator manually monitors the video / audio status of each program content restored / reproduced and output from the MPEG decoders 10 and 14 visually or by using a separate dedicated device. Unless it is used and monitored, the validity of the decrypted encryption keys KsA and KsB cannot be grasped.

  In addition, it is not easy to isolate the cause device when a broadcast failure occurs. Specifically, it is difficult to clearly identify where the malfunction is in the MPEG encoder 1, the video / audio scrambler 2, the multiplexer 3, the Ks scrambler 4, and the Ks scrambler 11 constituting the transmission system. .

  The present invention solves such problems, and its purpose is to encode and encrypt the validity of the encryption key encrypted by the “B-CAS” method and the “new RMP” method. An object of the present invention is to realize a broadcast wave encryption monitoring apparatus that can automatically monitor video / audio of each program content without decoding and decoding, and can easily identify a cause device when a broadcast failure occurs.

In order to achieve such a problem, the invention according to claim 1 of the present invention is:
In the broadcast wave encryption monitoring device of the digital broadcasting system where the encryption key that scrambles the program content consisting of video and audio is encrypted in parallel by the B-CAS system and the new RMP system,
A first encryption key decryptor for decrypting the encrypted encryption key based on a B-CAS scheme;
A second encryption key decryptor for decrypting the encrypted encryption key based on a new RMP method;
A comparator that compares the first cipher key decrypted and output from the first cipher key decryptor with the second cipher key decrypted and output from the second cipher key decryptor and collates the bit arrangement of the two. ,
It is characterized by including.

The invention of claim 2 is the broadcast wave encryption monitoring apparatus of claim 1,
further,
A switching unit that selectively switches and outputs the first encryption key and the second encryption key input to the comparator;
A PES packet decoder that decrypts a PES packet based on the encryption key output from the switching unit;
MPEG decoder that decodes the PES packet output from this PES packet decoder,
It is characterized by including.

  As a result, the legitimacy of the encryption key encrypted with the B-CAS method and the new RMP method can be automatically monitored without decoding and decoding the video and audio of each program content that is encoded and encrypted. It is easy to identify the cause device when a broadcast failure occurs.

It is a block diagram which shows one Example of this invention. It is a block diagram which shows the example of a connection of the broadcast wave encryption monitoring apparatus based on this invention in a broadcast system. It is a block diagram which shows the other example of a connection of the broadcast wave encryption monitoring apparatus based on this invention in a broadcast system. It is a block diagram of the conventional broadcasting system comprised so that the encryption key Ks might be encrypted by a B-CAS system. It is a block diagram which shows an example of the conventional broadcast wave encryption monitoring apparatus. It is a block diagram which shows the example of a connection of the broadcast wave encryption monitoring apparatus in the conventional broadcast system.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of the present invention, and the same reference numerals are given to portions common to FIG. 1 differs from FIG. 6 in that a comparator 15 is provided in place of the PES packet decoder 9 and MPEG decoder 10 and the PES packet decoder 13 and MPEG decoder 14 of FIG.

  The packet discriminator 7 generates a first ECM packet including the encrypted encryption key Ks′A and a second ECM packet including the encrypted encryption key Ks′B from the multiplexed transport stream TS. Discriminate and separate. The packet discriminator 7 discriminates and separates PES packets including encrypted video / audio, but is not shown in FIG.

  At one input terminal of the comparator 15, the encryption key encrypted by the first Ks scrambler 4 by the “B-CAS” method is decrypted by the first Ks decoder 8 based on the “B-CAS” method. The first encryption key KsA is input, and the encryption key encrypted by the second Ks scrambler 11 by the “new RMP” method is input to the other input terminal by the second Ks decoder 12 and “new RMP”. The second encryption key KsB decrypted based on the method is input.

  The comparator 15 compares and collates the bit sequences of the first encryption key KsA decrypted and output from the first Ks decoder 8 and the second encryption key KsB decrypted and output from the second Ks decoder 12. The comparison result is output.

  The first encryption key KsA decrypted and output from the first Ks decoder 8 and the second encryption key KsB decrypted and output from the second Ks decoder 12 encrypt one video or audio stream. Should be the same because they are common keys.

  Therefore, if the bit array of KsA and KsB is compared by the comparator 15 and the two match, Ks′A included in the first ECM packet and Ks′B included in the second ECM packet are It can be determined that the data is correctly encrypted.

  On the other hand, if the result of comparison by the comparator 15 is that they do not match, the first Ks scrambler 4 that encrypts the encryption key Ks by the “B-CAS” method or the encryption key by the “new RMP” method. It can be seen that either one of the second Ks scramblers 11 that encrypts Ks, or both the first Ks scrambler 4 and the second Ks scrambler 11 have failed.

  From these, it is possible to monitor the operation of the first Ks scrambler 4 and the second Ks scrambler 11 that encrypt the encryption key Ks.

  FIG. 2 is a block diagram showing a connection example of a broadcast wave encryption monitoring apparatus according to the present invention in a broadcast system, and the same reference numerals are given to portions common to FIGS. In FIG. 2, the transport stream TS multiplexed by the multiplexer 3 is input to the modulator / transmitter 5, modulated, and then power amplified as a terrestrial digital broadcast transmission signal and transmitted via the antenna 6. .

  The packet of the transport stream TS multiplexed by the multiplexer 3 is also input to the packet discriminator 7, and the first ECM packet including the encrypted encryption key Ks'A and the encrypted encryption key Ks'B. To be separated into a second ECM packet including. Note that PES packets including encrypted video / audio are also discriminated and separated, but not shown.

  FIG. 3 is a block diagram showing another embodiment of the present invention. In addition to the comparison function of FIG. 2, it is determined whether the “B-CAS” type system or the “new RMP” type system is malfunctioning. This function is provided.

  In FIG. 3, the malfunction determination function includes a Ks switching unit 16, a PES packet decoder 9, and an MPEG decoder 10.

  The Ks switching unit 16 includes a first encryption key KsA decrypted and output from the first Ks decoder 8 input to the comparator 15 and a second encryption key decrypted and output from the second Ks decryptor 12. KsB is input, and either the first encryption key KsA or the second encryption key KsB is selectively switched and output as an encryption key to the PES packet decoder 9.

  The PES packet decoder 9 also receives a PES packet including encrypted video and audio that is discriminated and separated by the packet discriminator 7. The PES packet is selectively input from the Ks switching unit 16. The decryption is performed based on the first encryption key KsA or the second encryption key KsB.

  The PES packet decoded by the PES packet decoder 9 is input to the MPEG decoder 10, and the video / audio of the program content that has been encoded is restored and reproduced.

  When the monitoring operator of the broadcast station confirms the occurrence of a broadcast failure from the mismatch of the comparison result output of the comparator 15, the broadcast operator operates the Ks switching unit 16 to set the encryption key Ks input to the PES packet decoder 9 to the first encryption. While switching to the key KsA or the second encryption key KsB, the restoration / reproduction state of the video / audio of each program content in the state in which the respective encryption key Ks is input is determined visually.

  If the video / audio of each program content can be correctly restored and played with only one of the encryption keys Ks, it can be determined that the other encryption key Ks system is malfunctioning. If the video / audio of the content cannot be correctly restored and reproduced, it can be determined that both systems are malfunctioning or that other parts other than the encryption key Ks system are malfunctioning.

  Furthermore, if the comparison result output of the comparator 15 is consistent and normal, but the video / audio of each program content cannot be correctly restored and reproduced, it is clearly determined that the other parts other than the encryption key Ks system are malfunctioning. it can.

  Whether encryption / decryption of encryption key Ks using the "new RMP" method was correctly performed or not was determined by audiovisual judgment whether the video / audio of each program content was finally correctly restored and played back However, according to the present invention, it is possible to automatically monitor the operation of encryption and decryption. In the unlikely event that the video / audio of each program content is interrupted, the cause portion can be easily identified by referring to the comparison result output of this apparatus.

  Specifically, if there is no abnormality in the comparison result output of this device when the video / audio of each program content is interrupted, the operation of the video / audio scrambler that scrambles the video / audio using the encryption key Ks There is a problem with the legitimacy or video / audio stream data (PES packet).

  If there is an abnormality in the comparison result output of this device when the video / audio is interrupted, it turns out that there is a problem in the operation of either or both of the "B-CAS" system and the "New RMP" system . As described above, it becomes possible to immediately isolate the cause.

  Conventionally, video and audio have been monitored audiovisually or with dedicated devices, so in addition to manual operations, video and audio monitoring devices, or dedicated devices, MPEG decoders that decode video and audio are "B-CAS. It was necessary for each of the "new RMP" method, but it has the effect of reducing these facilities and manpower to only one system. If FIG. 3 and FIG. 6 are compared, it is clear that this equipment is completed with one system.

  As described above, according to the present invention, the video / audio of each program content encoded and encrypted with the validity of the encryption key encrypted by the “B-CAS” method and the “new RMP” method. Can be automatically monitored without decoding and decoding, and a broadcast wave encryption monitoring device can be realized that can easily identify the cause device when a broadcast failure occurs.

7 Packet discriminator 8 First Ks decoder 2
9 PES packet decoder 10 MPEG decoder 15 Comparator 16 Ks switching unit

Claims (2)

In the broadcast wave encryption monitoring device of the digital broadcasting system where the encryption key that scrambles the program content consisting of video and audio is encrypted in parallel by the B-CAS system and the new RMP system,
A first encryption key decryptor for decrypting the encrypted encryption key based on a B-CAS scheme;
A second encryption key decryptor for decrypting the encrypted encryption key based on a new RMP method;
A comparator that compares the first cipher key decrypted and output from the first cipher key decryptor with the second cipher key decrypted and output from the second cipher key decryptor and collates the bit arrangement of the two. ,
And a broadcast wave encryption monitoring device. further,
A switching unit that selectively switches and outputs the first encryption key and the second encryption key input to the comparator;
A PES packet decoder that decrypts a PES packet based on the encryption key output from the switching unit;
MPEG decoder that decodes the PES packet output from this PES packet decoder,
The broadcast wave encryption monitoring apparatus according to claim 1, comprising:

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