JPH07255049A - Scrambling control unit - Google Patents

Abstract

PURPOSE:To instruct descrambling directly to a decoder which belongs to a different network by outputting partial decoder information onto outside media and handing the outside media over. CONSTITUTION:The scrambling control unit 1 of a network A specifies the identifiers 20 of decoders by an output decoder specifying means 12 so as to list up the decoders of the network A which are desired to receive a video and audio program sent out of a network B. The identifier 20 is inputted to a decoder information output means 13, and decoder information 22 is retrieved in a database 11 by using the identifiers 20 as keys and recorded on the outside media 4. The outside media 4 received from the network A is inputted to the decoder information input means 14 on the scrambling control unit 2 of the network B and the decoder information 22 on the outside media 4 is additionally registered in the database 11. Consequently, descrambling can be instructed directly to decoders belonging to other networks.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scramble control device which scrambles a video / audio signal and distributes it particularly in satellite communication and satellite broadcasting.

[0002]

2. Description of the Related Art In satellite communication, in order to conceal the contents of communication, a video / audio signal is scrambled and transmitted, and only a decoder having a viewing right unscrambles and views. Especially in corporate communication called business television, a network closed by a specific decoder is formed and video is distributed within the private network.

FIG. 3 is a block diagram showing an example of this scramble control system. Each decoder 5 has a unique identifier 20 and a unique encryption key 21 built into each decoder, and the scramble control device 3 of the transmitting station manages the pair as decoder information 22. The identifier 20 is a different decoder number for each decoder. Work key 2 with a relatively long update period prior to sending video and audio signals
Individual information 24 only for the specific decoder that has the right to view 3
I will send it in advance. Since the destination of the individual information 24 is designated by the decoder identifier 20 and is encrypted and transmitted by the encryption key 21, only the designated decoder having the encryption key 21 can decrypt the individual information to obtain the work key 23. Then, when transmitting the video / audio signal, the scramble key 25
Then, the video / audio signal 30 is scrambled. The video / audio signal becomes a scrambled signal 31. Since the scramble key 25 is updated in a short time of about 1 second, every time it is updated, its value is broadcasted to all the decoders by the common information 26 to inform it. Since the common information 26 is encrypted by the work key 23 and is sent, the work information 23 is previously transmitted by the individual information 24.
Only the specific decoder which obtains the encrypted information can obtain the scramble key 25 by decrypting the common information, and the scramble key 25 can be used to decrypt the scramble and view the video / audio signal 30. After all, sending the individual information 24 including the work key 23 from the scramble control device to the decoder is the instruction of the descramble to the decoder.

FIG. 2 is a conceptual diagram of a conventional scramble control device. In FIG. 2, 3 is a scramble control device. 10 is a decoder information management means,
Decoder information 22 consisting of a pair of an identifier 20 and an encryption key 21 is managed in the form of a database 11 for a decoder belonging to a network in which the transmitting station distributes video. Descrambling instruction means 15 creates individual information 24 including a work key for a decoder having a viewing right, encrypts it with an encryption key 21 unique to each decoder, and sends it out.

There is only one network to which one decoder belongs, and the decoder information is recorded only in the scramble controller of the network to which it belongs.

On the other hand, the decoder which the scramble control device 3 can send the individual information 24 to directly instruct the descramble must know the encryption key 21 of the decoder, so that the internal decoder information management means 10 manages it. Limited to existing decoders. Therefore, the only decoder that can instruct descrambling is a decoder belonging to its own network. Decoders belonging to other networks have a problem that they cannot directly instruct descramble because they are not managed by the decoder information management means.

In the conventional scramble control device, when the decoder belonging to the network A tries to descramble the video / audio signal transmitted from the scramble control device of the other network B, the work key used in the network B is preliminarily set. Then, the value of the work key is exchanged between the transmission managers of the network, and the scramble controller of the network A that knows the encryption key unique to the corresponding decoder creates individual information including the work key, It was necessary to take an indirect procedure of encrypting with the encryption key unique to the decoder and then sending it to the corresponding decoder in advance and instructing descramble in advance. The procedure is that the scramble control device of network A sends individual information in advance, and the scramble control device of network B sends common information and video / audio signals afterwards. Because the channels are different, the receiving channel for individual information and the receiving channel for video / audio signals are different channels, and some decoders cannot reliably receive the individual information. As a result, there is a problem that the video / audio signals cannot be descrambled.

[0008]

In view of the above, the present invention has a scramble control capable of directly instructing a decoder belonging to another network to descramble as well as a decoder belonging to its own network. It is an object of the present invention to provide a device so that decoders belonging to other networks can receive individual information without fail and to decramble video / audio signals.

[0009]

SUMMARY OF THE INVENTION According to the present invention, an output decoder designating means for designating a part of the decoder information out of the decoder information managed by the decoder information managing means in the form of a database, and a designated part. Is a scramble control device comprising decoder information output means for outputting the decoder information on the external medium to an external medium and decoder information input means for internally capturing the decoder information on the external medium and adding it to the database.

[0010]

According to the present invention, with the above-described configuration, a part of the decoder information is output onto the external medium, and the decoder information is taken into the scramble control device of the other network by passing the external medium to the other medium. The descramble can be directly instructed by directly sending individual information from the scramble controller to the corresponding decoder.

[0011]

1 is a conceptual diagram of a scramble control device according to an embodiment of the present invention. In FIG. 1, 1
Is a scramble control device for network A, and 2 is a scramble control device for different network B, and their internal configurations are exactly the same.

Decoder information management means 10 manages decoder information 22 consisting of an identifier 20 and an encryption key 21 in the form of a database 11 for the decoders belonging to the network.

An output decoder designating unit 12 designates an identifier 20 of a specific decoder which outputs the decoder information. In this embodiment, the decoder identifier 20 is designated by a ten-key input keyboard. Reference numeral 13 is a decoder information output means, which searches the database 11 for a decoder having the specified identifier 20 and
Decoder information 22 including a pair of the encryption key 21 and the encryption key 21 is output to the external medium 4. In the present embodiment, by successively designating a plurality of identifiers 20, the decoder information 22 regarding a plurality of decoders can be collectively output on the same external medium. In this embodiment, a floppy disk is used as the external medium 4. The external medium 4 may be an IC card or a memory card instead of the floppy disk, and may simply display the decoder information on the CRT display.

Reference numeral 14 is a decoder information input means for reading the decoder information 22 recorded on the external medium 4,
It is additionally registered in the database 11. In this embodiment, the decoder information on the floppy disk is automatically read. When the external medium is an IC card or a memory card, the automatic reading device corresponds to each medium. Further, when the external medium is a CRT display, the value of the displayed decoder information may be directly input from the keyboard.

Numeral 15 is a descrambling instruction means, which is an individual information 24 including a work key for a decoder having a viewing right among the decoders registered in the database 11.
Is descried and encrypted with the encryption key 21 peculiar to the decoder and sent in advance to instruct descramble.

Deletion decoder designating means 16 designates the identifier 20 of the decoder to be deleted from the database. In the present embodiment, each decoder information 22 inside the database is provided with an expiration date 27, and when the expiration date expires, it is targeted for deletion. The deletion decoder designating means 1
Alternatively, the identifier 20 of the decoder may be directly designated by a ten-key keyboard. Reference numeral 17 is a decoder information deleting means, which is the decoder information 22 of the specified identifier 20.
Is deleted from the database 11.

The operation of the scramble control device of this embodiment having the above structure will be described below.

For decoders belonging to network A,
The scramble control device of network B directly instructs descramble,
The procedure for viewing an audio program is as follows.

First, in the scramble control device 1 of the network A, in order to list up the decoders of the network A which the user wants to watch the video / audio program transmitted by the network B, the output decoder designating means 12 designates the decoder identifier 20. . This identifier 20 is input to the decoder information output means 13, and the decoder information output means 1
3 is the decoder information 2 from the database 11 managed by the decoder information management means 10 using the identifier 20 as a key.
2 is searched, and the searched decoder information 22 is recorded in the external medium 4. The transmission manager of network A transfers this external medium 4 to the transmission manager of network B.

Next, in the scramble control device 2 of the network B, the external medium 4 received from the network A is input to the decoder information input means 14, and the decoder information 22 on the external medium 4 is additionally registered in the database 11. The scramble control device 2 of network B
When transmitting the audio program, the descrambling instruction means 15
It is possible to send the individual information to any of the decoders on the database 11 to instruct the descramble, and the decoder of the network A additionally registered by the decoder information input means 14 is included therein. . Therefore, the decoder of network B originally existing on the database and the decoder of network A additionally registered can be treated equally and the descramble can be directly instructed in exactly the same manner. For the decoder belonging to the network A, all the individual information, common information, and video / audio signals are sent from the scramble control device of the network B on the same satellite channel, and the probability of normally receiving the individual information is extremely high. Become. In the present embodiment, the individual information is not only sent in advance before the video / audio signal, but also the individual information is repeatedly sent in parallel with the sending of the video / audio signal even after the program starts. Can be received.

If the decoder information transferred through the external medium is provided with an expiration date so that the scramble control device of another network can use the decoder information for a limited period, the confidentiality of each network can be further improved. It can be a secure scramble control device. The operation will be described below.

Scramble controller 1 of network A
Then, when the decoder information output means 13 records the decoder information 22 on the external medium 4, the expiration date 27 is also recorded. In this embodiment, the expiration date 27 is a fixed value after a fixed period from the time when the operation of outputting the decoder information is performed.
The expiration date 27 may be explicitly specified together with the identifier from the keyboard when the decoder identifier 20 is specified by the output decoder specifying means.

Next, in the scramble control device 2 of the network B, when the decoder information input means 14 fetches the decoder information 22 from the external medium 4 into the database 11,
The expiration date 27 is also captured and recorded together with the decoder information. At this time, with respect to the decoder originally belonging to the network B in the database, the decoder information is valid indefinitely. The deletion decoder designating means 16 manages the expiration date of the decoder information, and when the expiration date expires, instructs the decoder information deleting means 17 of the decoder identifier 20, and the decoder information deleting means 17 stores the decoder information 22 of the corresponding decoder in the database. Delete from 11. For decoders whose decoder information has been deleted,
After that, it becomes impossible to send the individual information 24 from the scramble controller 2 of the network B to directly instruct the descramble.

An identifier of each network is provided, and when outputting the decoder information to an external medium, the identifiers of other networks that permit the decoder information to be taken in through the external medium are recorded together with the external medium. Good. By doing so, even if the external medium is stolen, there is no fear that the decoder information on the external medium will be taken into the scramble control device of the network other than the identifier recorded in the external medium. Can be

[0025]

As described above, according to the present invention,
It is possible to output a part of the decoder information managed by the scramble controller of each network to an external medium and, conversely, take it in from the external medium into the scramble controller. This makes it possible to exchange decoder information between different networks by exchanging an external medium between scramble control devices of different networks and directly instruct descrambles to decoders belonging to other networks. The decoder can reliably receive the instruction and descramble it, and its practical effect is great.

[Brief description of drawings]

FIG. 1 is a conceptual diagram of a scramble control device according to an embodiment of the present invention.

FIG. 2 is a conceptual diagram of a conventional scramble control device.

FIG. 3 is a block diagram of a scramble control method.

[Explanation of symbols]

 1 Scramble Control Device (Network A) 2 Scramble Control Device (Network B) 3 Scramble Control Device (Conventional) 4 External Medium 5 Decoder 10 Decoder Information Management Means 11 Database 12 Output Decoder Designating Means 13 Decoder Information Output Means 14 Decoder Information Input Means 15 descrambling instruction means 16 deletion decoder designating means 17 decoder information deleting means 20 identifier 21 encryption key 22 decoder information 23 work key 24 individual information 25 scramble key 26 common information 27 expiration date 30 video / audio signal (non-scrambled state) 31 video・ Voice signal (scrambled)

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Claims (2)

[Claims] 1. A scramble control device that scrambles a video / audio signal for distribution, and encrypts individual information necessary for descrambling to a decoder having a viewing right with an encryption key unique to each decoder and transmits the encrypted information. Decoder information management means for holding, as a database, decoder information composed of a pair of an identifier unique to the decoder and an encryption key unique to the decoder, an output decoder designating means for designating the identifier of a part of the specific decoders, and the output decoder Decoder information output means for outputting the decoder information of the decoder designated by the designation means onto an external medium, and decoder information input means for taking in the decoder information on the external medium inside and adding it to the database A scramble control device characterized by. 2. Decoder information output means for outputting decoder information with an expiration date on an external medium; decoder information input means for internally capturing the expiration date together with the decoder information from the external medium and adding it to a database; 2. The scramble control device according to claim 1, further comprising decoder information deleting means for deleting the expired decoder information from the database.