JP2000092013A - Transmitting device, receiving device, and system using the same - Google Patents

Abstract

(57) [Problem] To provide a transmitting apparatus and a receiving apparatus of a conditional access system for digital cable television broadcasting and a system using the same. On the transmission side, content data is scrambled according to an operation result of two types of key data of a first key data and a second key data on a transmission stream format, and encrypted key data is transmitted. Is transmitted using digital modulation means such as multi-level QAM such as 64 values, or an information storage medium or digital modulation means such as FSK. On the receiving side, the encrypted key data is received and decrypted using digital demodulation means such as multi-level QAM such as 64 values or digital demodulation means such as an information storage medium or FSK, and the first key data is decrypted. In addition, content descrambling is performed based on the operation result of the two types of key data of the second key data, and digital data in a transport stream format is received.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmitter and a receiver for television broadcasting and a system using the same. The present invention relates to a conditional access system that specifies and permits reception.

[0002]

2. Description of the Related Art Conventionally, as for a conditional access system in television broadcasting using a CATV transmission line called a cable television, a cable television technology committee, published by Corona, edited by the Cable Machinery Engineering Committee of the Electronic Machinery Manufacturers Association. Getting Started ”. According to the description, a method called a one-way addressable system is described.
In this method, the descrambling function in the home terminal on the receiving side is controlled by the FSK modulation downlink from the transmitting side. Although there is no detailed description of the scramble system,
In the following circumstances, the method has changed while progressing.
First, as a simple conditional access method, there was a popular name channel skip method that restricts the selection of a CATV receiver by downlink control information transmitted by FSK modulation or the like in a band other than the channel transmitting the video signal. . According to the channel skip method, a CATV receiver skips receivable channels according to downlink control information so that a receiver cannot receive a channel for which the receiver has not subscribed. When was sold to general users, the restrictions on channel selection were eliminated, and it became possible to receive channels that had been skipped, so the function of the above-mentioned method became meaningless.
As another conditional access system, there is a scramble system of synchronous compression. In this method, the level of the horizontal synchronization signal of NTSC video is transmitted at a reduced level, so that it cannot be played back on a TV receiver that supports the CATV channel. When receiving a contracted channel, the level can be reproduced by extending the period of the horizontal synchronizing signal, which has been compressed and reduced to a normal level. The scramble system of the synchronous compression is generally used as a conditional access system for analog television broadcasting for transmitting NTSC video, but does not describe a conditional access system for digital cable television broadcasting.

[0003] With the recent development of digital transmission technology and the like, NTSC video transmission channels, which are analog signals, are transmitted.
A number of digitized images are being transmitted on one channel. Regarding the digital transmission of this cable television, see the Telecommunications Society of Japan Technical Report (vol.19, No.42) published on September 21, 1995, pages 19 to 24, John Broadcasting Transmission Experiment ". According to this report, Empeg 2 (MP
EG2) is a data stream in a format called a transport stream in which digital data such as images compressed by digital image compression technology called multiplexed data is processed. The signal is modulated by a digital modulation technique called "modulation" and transmitted on a CATV transmission line. This report does not describe the conditional access system.

[0004] On the other hand, there is a digital satellite television broadcast as a method for distributing multi-channel digitized video, which is described in Nikkei Electronics 1996.
This is realized by a combination of digital image compression technology and digital transmission technology, as described in the paper "Sep. According to this paper, a conditional access system that specifies a recipient and permits reception is realized by a scrambling system unique to Japan and descrambling by an IC card. As described above, the satellite television broadcasting is a system using an IC card or a telephone line without an upstream line for transmitting information from each home to a transmitting side for broadcasting via a satellite. In this paper, there is no description for adapting the scramble system and the conditional access system for descrambling by the IC card to other transmission systems such as digital cable television broadcasting.

A conditional access system for digital television broadcasting of cable television is described in Japan.
The standardization method was examined by the Standardization and Standardization Committee of the CATV Technology Association, and in April 1997, JCTEA STD 001-1.0 was issued. According to this, in a manner similar to the above satellite television broadcast, the transmitting side scrambles a transport stream such as video or audio with first key data, and then encrypts the first stream encrypted with second key data. The key data is time-division multiplexed with a transport stream such as video and audio scrambled by the first key data. Further, the second key data is encrypted by the third key data, the encrypted second key data is the video and audio scrambled by the first key data and the encrypted first key data It is time-division multiplexed with transport stream data such as key data and transmitted. This output data stream is modulated by a modulating means for digitally modulating such as 64QAM, and a plurality of modulated waves are frequency-multiplexed by a signal synthesizing means and transmitted to a transmission path. Here, a method of storing the third key data in an IC card is considered.

On the other hand, the receiving side demodulates digital modulated waves such as multi-level QAMs such as 64-values transmitted in a frequency multiplexed manner by demodulation means, performs error correction, and multiplexes the waves by an MPEG separation circuit. Separate port streams.
The encrypted second key data included in the separated transport stream is decrypted using the third key data obtained in advance from the IC card, and the encrypted second key data included in the separated transport stream is decrypted. The decrypted first key data is decrypted using the decrypted second key data. By using the decrypted first key data, the scrambled video and audio can be decrypted. The decoded video and audio transport streams are separated by an MPEG separation circuit and are reproduced by respective decoders.

[0007]

Conventionally, there is no detailed definition of a conditional access system for digital cable television broadcasting using a CATV transmission line, and in a channel skip system like a conventional analog receiver, a digital When a television receiver compatible with cable television broadcasting is sold to general users, the function of conditional access is lost. In digital cable television broadcasting, the signal to be transmitted is not an NTSC video and there is no horizontal synchronization signal. Under these circumstances, it is conceivable to adopt a conditional access method for digital satellite television broadcasting that transmits the same type of transport stream. Not been. Satellite television broadcasting is broadcast to viewers nationwide, whereas cable television broadcasting is broadcast to viewers in a limited area with a cable. As a conditional access system for cable television broadcasting, a system having a simple configuration and considerable security is desired.

An object of the present invention is to provide a transmission apparatus and a reception apparatus of a conditional access system for digital cable television broadcasting in which digital data relating to a program such as a compressed image is transmitted in a format called a transport stream, and to use the transmission apparatus. It is to provide a system.

[0009]

In order to solve the above-mentioned problems, the present invention provides first key data and second key data for scrambling a part of digital data in the mpeg transport stream format. Content scrambling means for performing a scramble operation using the operation results of the two types of key data is provided, and both the first key data and the second key data are converted to third key data or fourth key data. Both or one of the first key data encryption means and the second key data encryption means to encrypt the first encryption key information and the second encryption key information, the first encryption key information and Both or one of the second encryption key information, the third key data, and / or the fourth key data is time-division multiplexed in an mpeg transport stream format to form 64 values or the like. Transmission means for transmitting using a first modulation means for performing digital modulation such as value QAM or a second modulation means for performing digital modulation such as FSK or information storage means such as a semiconductor memory or an IC card capable of storing data, First demodulation means for performing digital demodulation such as multi-level QAM such as 64 values transmitted by frequency multiplexing, and time-division multiplexed data in the MPPEG transport stream format which is the output of the first demodulation means. Time division multiplexing / demultiplexing means for separating content-scrambled data, and information obtained by the time division multiplexing / demultiplexing means or information storage means such as a semiconductor memory or an IC card or second demodulation means for performing digital demodulation such as FSK. The first encryption key information and the second encryption key information and / or the third key data and / or the fourth key data.
The key data and the second key data are obtained, and the content scrambled data obtained by the first demodulation means is obtained by the operation result of the two types of key data of the first key data and the second key data. Descrambling means for obtaining transport stream format digital data from
Is provided.

That is, on the transmitting side, the digital data in the transport stream format is scrambled according to the operation result of the two types of key data of the first key data and the second key data, and is transmitted. The data is transmitted without scrambling using digital modulation means such as multi-valued QAM such as 64 values, or an information storage medium or digital modulation means such as FSK.

On the receiving side, the encrypted key data is received and decrypted using digital demodulation means such as multi-level QAM such as 64 values or digital demodulation means such as an information storage medium or FSK, and the first key data is decrypted. Key data and second
The content scramble is released according to the operation result of the two types of key data, and digital data in the transport stream format is received.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a block diagram showing a configuration of a conditional access transmission apparatus for a cable television and an arrangement of the reception apparatus according to an embodiment of the present invention. In FIG. 1, reference numeral 100 denotes a transmission-side encryption modulator, 200 denotes a transmission-side video signal source device, 300 denotes a transmission-side key management device, 400 denotes a CATV transmission path,
500 is a receiving terminal device, 600 is a video / audio output device, 700 is delivery means such as mailing, 101 is an encryption device, 102 is a time division multiplexing circuit, 103 is 64 QAM (Quadrature Amplitude Modulation)
Modulation circuit, 104 is a signal synthesis circuit, 111 is a data multiplexing and content scrambling circuit, 112 is a first key encryption circuit, 113 is a second key encryption circuit, 151 is video / audio data, 1
52 is the first key data, 153 is the second key data, 154 is the third key data, 155 is the encrypted first key information, 156 is the encrypted second key information, 157 is Scrambled video / audio data, 158 is scrambled video / audio key information multiplexed data, 159
Is a 64QAM digital modulated wave signal, 501 is a frequency multiplexed signal separation circuit, 502 is a control microcomputer, 503 is a 64QAM demodulation circuit, 5
04 is an error correction circuit, 505 is a key data separation circuit, and 506 is a second
507 is a first key decryption circuit, 508 is a content descramble circuit, 509 is an MPEG demultiplexing circuit, 510 is
MPEG video decoder, 511 is NTSC (National Television
System Committee) Video encoder, 512 is audio decoder, 513 is information storage medium, 551 is control signal, 552 is 6
4QAM modulated wave signal, 553 is 64QAM demodulated digital data, 55
5 is digital data after error correction, 556 is the encrypted first
557 is encrypted second key information, 558 is third key data, 559 is second key data, 560 is first key data,
561 is descrambling digital data, 562 is compressed video data, 564 is video data, 563 is compressed audio data,
565 is an NTSC video signal, and 566 is an analog audio signal.

A cable television transmission device having a conditional access system is composed of a transmission side encryption / modulation device 100, a transmission side video signal source device 200, and a transmission side key etc. management device 300. The video and audio data 151 including video and audio data from the MFP is digital data in the MPEG2 transport stream format or a format that can be converted into a transport stream, and is input to the data multiplexing and content scrambling circuit 111 of the encryption device 101. And the first key data from the transmission-side key etc. management device 300.
The video and audio data of the digital data in the transport stream format is scrambled by the 152 and the second key data 153 into scrambled video and audio data 157, which is applied to the time division multiplexing circuit 102. The first key data 152 and the second key data 153 obtained by encrypting the video / audio data 151 into scrambled video / audio data 157 are stored in the first key encryption circuit 11.
In the second and second key encryption circuits 113, the transmission-side key etc.
The first key information 155 and the second key information 156 which are encrypted with the third key data 154 from Time division multiplexing circuit 1
In 02, the encrypted first key information 155, the encrypted second key information 156, and the scrambled video / audio data 157 are time-division multiplexed as digital data in a transport stream format, and the scrambled video / audio The key information multiplexed data 158 is added to the 64QAM modulation circuit 103. 64Q
The AM modulation circuit 103 adds an error correction code to the scrambled video / audio key information multiplexed data 158, performs interleaving processing, energy spreading processing, etc., converts it to a 64QAM digital modulated wave signal 159, and passes through the signal synthesis circuit 104 The signal is frequency-multiplexed with another 64QAM digital modulated wave signal, analog modulated wave signal, or the like, and output to the CATV transmission line 400. The third key data 154 is an information storage medium such as an IC card.
513, etc., and an information storage medium 513 such as an IC card.
Are distributed to a cable television receiving apparatus having a conditional access system by a delivery means 700 such as mail.

On the other hand, a receiving device for a cable television having the conditional access system includes a receiving terminal device 500. In the receiving terminal device 500, the frequency multiplexed and transmitted 64Q
The AM digital modulated wave signal is received from the CATV transmission path 400, and the 64QAM modulated wave signal 552 selected by the frequency multiplexing signal separation circuit 501 in accordance with the control signal 551 from the control microcomputer 502 is 6
The signal is input to the 4QAM demodulation circuit 503. 64Q with 64QAM demodulation circuit 503
The AM modulated wave signal 552 is demodulated into 64QAM demodulated digital data 553, and an error in the data generated on the transmission line is corrected by an error correction circuit 504. Input to 505. The error correction circuit 504 also performs decoding of data that has been subjected to the interleave processing and the energy diffusion processing. In the key data separation circuit 505, the encrypted first key information 556 and the encrypted second key information 557 are obtained. In the first key decryption circuit 507 and the second key decryption circuit 506, the third key data 55 obtained from the information storage medium 513 such as an IC card obtained via the delivery means 700 such as mailing.
8, the encryption of the first key information 556 and the encryption of the encrypted second key information 557 are decrypted, and the first key data 560 and the second key data 559 are obtained. The content descramble circuit 508 decodes the error-corrected digital data 555 encrypted with the obtained first key data 560 and second key data 559, and outputs the descrambled digital data in the MPEG2 transport stream format. The data is returned to 561, and compressed video data is
The data is separated into 562 and compressed audio data 563 and input to the MPEG video decoder 510 and the audio decoder 512. The compressed video data 562 is converted into video data 564 by an MPEG video decoder 510, and is converted into an NTSC video signal 565 by an NTSC video encoder 511. The compressed audio data 563 is converted into an analog audio signal 566 by the audio decoder 512. The NTSC video signal 565 and the analog audio signal 566 are input to the video / audio output unit 600, and information such as video and audio displayed on the video / audio output unit 600 can be provided to the viewer.

Regarding input / output of data using an IC card, for example, data input is performed by an IC card issuer using a personal computer or the like under the control of the transmission side key management device 300, and data output is performed. Receiving terminal device 500
May be performed by using a socket under the management of.

As described above, in the present embodiment, when the viewer watches the contracted channel, the first key data 560 and the second key data 559 are obtained, so that the content scrambled error Digital data after correction 55
5 can be decrypted and returned to the descrambled digital data 561 in the MPEG2 transport stream format,
Information such as video and audio of the contracted channel can be obtained. Even if an unsubscribed viewer tries to view an unsubscribed channel, the first key data 560 and the
Since the second key data 559 cannot be obtained, the error-corrected digital data 555 subjected to the content scramble cannot be decoded, and information cannot be obtained. That is, a conditional access system of digital cable television broadcasting is achieved.

In this embodiment, the method in which the first key data and the second key data are encrypted with the third key data is used. And a conditional access system of digital cable television broadcasting can be realized regardless of the number of keys. Note that eavesdropping becomes more difficult as the number of keys is increased.

In this embodiment, a method of transmitting key data by delivering an IC card in which key data is stored has been described. Alternatively, an IC memory in which key data is stored in advance may be received. Built in the device,
A method of transmitting key data inside the receiving device, a method of transmitting key data from a remote control by incorporating an IC memory in which key data is stored in advance in a remote controller corresponding to the receiving device, and a method of transmitting key data via a network server And a method of transmitting key data by a modem via a telephone line.

FIG. 2 is a block diagram showing a configuration of a transmission apparatus of a conditional access system for a cable television according to another embodiment of the present invention and a configuration of the reception apparatus. In FIG. 2, 201 is
MPEG-TS time division multiplexing circuit, 202 is a content scramble circuit, 203 is an MPEG-TS demultiplexing circuit, 251 and 252 are video and audio data including video and audio data, 253 is MPEG-TS multiplexed data, The same reference numerals as those shown in FIG. 1 denote the same units or data as those described with reference to FIG.

FIG. 2 is a block diagram showing the transmission-side encryption modulator shown in FIG.
100 data multiplexing and content scrambling circuits 111
And the time-division multiplexing circuit 102 are replaced with the MPEG-TS time-division multiplexing circuit 201 and the content scramble circuit 202, and the key data separation circuit 505 and the MPEG multiplexing / demultiplexing circuit 509 are replaced with the MPEG-TS multiplexing / demultiplexing circuit 203.
It is configured in place of.

Video and audio data 25 including a plurality of video and audio data output from the transmission side video signal source device 200
1, 252 and the encrypted first key information 155 and the encrypted second key information 156 are added to the MPEG-TS time-division multiplexing circuit 201 and time-division multiplexed to obtain MPEG-TS multiplexed data 253. To be. Thereafter, in the content scramble circuit 202, the first key data output from the transmission-side key etc.
152 and scrambled video / audio key information multiplexed data 15 obtained by scrambling video / audio data of digital data in a transport stream format by second key data 153
8 is supplied to the 64QAM modulation circuit 103.

On the other hand, in the receiving terminal device 500, the MPE
The encrypted first key information 556 and the encrypted second key information 557 obtained by the G-TS demultiplexing circuit 203 are obtained by a first key decryption circuit 507 and a second key decryption circuit 506, The first key data 560 and the second key data 559 are decrypted by the third key data 558 obtained from the information storage medium 513 such as an IC card.
Is obtained. Using the first key data 560 and the second key data 559, the content descrambler 508 descrambles the content to be viewed and obtains the descrambling digital data 561 in the MPEG2 transport stream format. The MPEG-TS demultiplexing circuit 203 separates the descrambled digital data 561 into compressed video data 562 and compressed audio data 563.

As described above, the descrambled digital data 561 in the MPEG2 transport stream format, which is the output signal of the content descramble circuit 508, is converted from the MPEG-
The first key information 556 encrypted by the TS demultiplexing circuit 203 and the second key information 557 encrypted can be obtained by MPEG
This is because packets of video data and MPEG audio data are scrambled, and data of key information is transmitted without being scrambled. The packet structure is
5 and FIG. As shown in FIG. 5, in the MPEG-2 transport stream, a packet header 5001 is attached to a packet 5002 of MPEG video data and MPEG audio data, and a packet 5002 of MPEG video data and MPEG audio data is transmitted.
And a packet header 5001 attached thereto. As shown in FIG. 6, the packet header 5001 further includes a transport scramble control 6006. According to the transport scramble control 6006, it is possible to set a flag for controlling whether or not each packet of the transportable MPEG2 transport stream is scrambled, so that packets of MPEG video data and MPEG audio data can be set.
5002 is scrambled, and key information data can be transmitted without scrambling.

As described above, in the present embodiment, the key data separation circuit 505 and the MPEG multiplex separation circuit 509 of FIG. MPEG-TS demultiplexing circuit 203
And there is also an advantage that the circuit can be simplified.

In the following embodiments of the present invention, FIG.
The description based on the configuration shown in FIG. 2 and the description based on the configuration shown in FIG. 1 will be omitted, but the embodiment of the present invention can also be implemented based on the configuration shown in FIG.

FIG. 3 is a block diagram showing the structure of scrambling in the embodiment of the present invention. In FIG. 3, 300
0 is scramble, 3001 is input data switching, 3002 is output data switching, 3003 is CBC mode configuration, 3004 is O
FB mode configuration, 3005 is MULTI2 encryption device, 3006 is EO
R, 3007 is a register, 3051 is video and audio data, 3052 is scrambled video and audio data, 3053 is first key data, 305
4 is the second key data, 3055 is the MULTI2 encryption device input signal,
3056 is a MULTI2 encryption device output signal.

The structure of scramble 3000 in FIG. 3, video / audio data 3051, scrambled video / audio data 3052,
The first key data 3053 and the second key data 3054 correspond to the data multiplexing and content scrambling circuit 111 shown in FIG.
, The video / audio data 151, the scrambled video / audio data 157, the first key data 152, and the second key data 153. These are the content scramble circuit 202 shown in FIG. 2, the MPEG-TS multiplexed data 253,
It corresponds to scrambled video / audio key information multiplexed data 158 obtained by scrambling video / audio data of digital data in a transport stream format, first key data 152, and second key data 153.

Video / audio data 3051 is input data switching
According to 3001, if the block length is 8 bytes, it is processed in the configuration 3003 of the CBC mode, and if the block length is not 8 bytes, it is processed in the configuration 3004 of the OFB mode and the output data switching 3002, and the scrambled video / audio data 3052 Is output as In the configuration 3003 in the CBC mode, the video / audio data 3051 is subjected to exclusive OR processing (exclusive OR) with the signal data from the register 3007 in the EOR 3006, and the MULTI2
It is applied to the MULTI2 encryption device 3005 as an encryption device input signal 3055. Then, the MULTI2 encryption device input signal 3055
Is MULTI2 encrypted by the first key data 3053 and the second key data 3054 which are separately added to the MULTI2 encryption device 3005, is added to the register 3007 as the MULTI2 encryption device output signal 3056, and the output data switching 30
02 and output as scrambled video / audio data 3052. In the OFB mode configuration 3004, the signal data of the register 3007 is used as the MULTI2 encryption device input signal 3055 as the MULTI2 encryption device input signal 3055.
Added to encryption device 3005. The MULTI2 encryption device input signal 3055 is composed of first key data 3053 and second key data 3054 separately added to the MULTI2 encryption device 3005.
The MULTI2 encryption processing is performed and the signal data of the register 3007 is updated as the MULTI2 encryption device output signal 3056 and added to the EOR 3006. The exclusive OR (exclusive OR) processing with the video / audio data 3051 is performed to switch the output data. 3052 scrambled video / audio data via 3002
Is output as

FIG. 4 is a block diagram showing the configuration of the MULTI2 encryption device 3005 in the embodiment of the present invention. In FIG. 4, 4000 is a MULTI2 encryption device, 4001 is a key processing unit, 4002
Is the encryption unit, 4051 is the MULTI2 encryption device input signal, 4052 is
MULTI2 encryption device output signal, 4053 is first key data, 405
Reference numeral 4 denotes second key data, and reference numeral 4055 denotes key processed key data.

The MULTI2 encryption device 4000 uses the MUL shown in FIG.
This shows the details of the TI2 encryption device 3005,
The LTI2 encryption device input signal 4051 and the MULTI2 encryption device output signal 4052 correspond to the MULTI2 encryption device input signal 3055 and the MULTI2 encryption device output signal 3056 in FIG. Also,
First key data 4053 and second key data 405 in FIG.
4 is the first key data 3053 and the second key data 3054 in FIG.
Alternatively, the first key data 152 and the second key data 152 in FIG. 1 and FIG.
Key data 153.

First key data 4053 and second key data 40
Numeral 54 denotes key data 4055 that has been processed by the key processing unit 4001 and key-processed, and the key data 40 key processed by the encryption unit 4002.
The MULTI2 encryption device input signal 4051 is encrypted (scrambled) by 55 to obtain a MULTI2 encryption device output signal 4052.
Is obtained.

Note that the encryption algorithm of the MULTI2 encryption device is publicly available and registered in ISO-9979 / 0009.

FIG. 5 is an MPE for explaining the embodiment of the present invention.
FIG. 3 is a conceptual diagram illustrating a signal configuration of a G2 transport stream format. In FIG. 5, 5001 is a packet header, 5002
Indicates a packet of MPEG video data or MPEG audio data, and 5003 indicates an error correction code. The data of the descrambled digital data 561 returned to the MPEG2 transport stream format of the receiving terminal device 500 is a packet header 50 of 4 bytes.
16 bytes of Reed-Solomon data into 188 bytes of MPEG2 transport stream data consisting of 01 and 184 bytes of MPEG video data and MPEG audio data packets 5002
An error correction code 5003 called (204,188) is added.

FIG. 6 shows an MPE for explaining the embodiment of the present invention.
FIG. 3 is a conceptual diagram showing a signal configuration of a packet header in a G2 transport stream format. In FIG. 6, 6001 is a synchronization byte, 6002 is a transport error indicator, 60
03 indicates a payload unit start indicator, 6004 indicates a transport priority, 6005 indicates a packet identifier, 6006 indicates a transport scramble control, 6007 indicates an adaptation field control, and 6008 indicates a continuity index. FIG. 6 shows details of the 4-byte packet header 5001 shown in FIG. 5, and a packet identifier 6005 indicating what kind of data packet the MPEG video data or MPEG audio data packet 5002 is.
And a transport scramble control 6006 indicating whether or not the data packet has been scrambled. By this transport scramble control 6006, the MPEG video data shown in FIG.
It can be seen that the packet of the MPEG audio data is scrambled, and the data of the key information is transmitted without being scrambled.

FIG. 7 is a block diagram showing a configuration of a transmission apparatus of a conditional access system for a cable television according to another embodiment of the present invention and a configuration of the reception apparatus. In FIG. 7, reference numeral 751 denotes fourth key data, 752 denotes fourth key data,
Alternatively, the same reference numerals as those shown in FIG. 2 indicate the same units or data as those described with reference to FIG. 1 or FIG.

In this embodiment, the transmitting-side encrypted modulation device 10
The first key data 152 of 0 is encrypted by the first key encryption circuit 112 with the third key data 154 obtained from the transmission side key etc. management device 300, and the second key data 153 is the second key data 153. The encrypted first key information 155 and the encrypted second key information 156, which are encrypted with the fourth key data 751 obtained from the transmission-side key etc. management device 300 by the encryption circuit 113, are MPEG-coded. It is added to the TS time division multiplexing circuit 201, and the same processing as in FIG. 2 is performed and transmitted. The third key data 154 and the fourth key data 751 are stored in an information storage medium 513 such as an IC card and distributed as described in FIG.

On the other hand, in the receiving side terminal device 500, the MPE
The encrypted first key information 556 obtained by the G-TS demultiplexing circuit 203 is decrypted by a first key decryption circuit 507 using third key data 558 obtained from an information storage medium 513 such as an IC card. Thus, first key data 560 is obtained. Encrypted second
The key information 557 is decrypted by the second key decryption circuit 506 using the fourth key data 752 obtained from the information storage medium 513 such as an IC card to obtain the second key data 559. The first key data 560 and the second key data 559 are added to the content descrambling circuit 508, and the encrypted error-corrected digital data 555 is decrypted, and the descrambled digital data 56 in the MPEG2 transport stream format is decoded.
Returned to 1.

In the present embodiment, in addition to being able to fulfill the conditional access system of digital cable television broadcasting, the third key is used as key data for encrypting the first key data 152 and the second key data 153. Since two types of data 154 and fourth key data 751 are used, it becomes more difficult to analyze the key data than in the embodiment using only the third key data 154 shown in FIG. 2, and it becomes difficult to decrypt the encryption. There is an advantage that.

FIG. 8 is a block diagram showing a configuration of a transmission apparatus of a conditional access system for a cable television according to another embodiment of the present invention and a configuration of the reception apparatus. In FIG. 8, 801 is
FSK (Frequency Shift Keying) modulation circuit, 802 is an FSK demodulation circuit, 851 is an FSK modulated wave signal, 852 is an FSK modulated wave signal subjected to frequency multiplex separation, 853 is FSK demodulated third key data, The same reference numerals as those shown in FIG. 1 or 2 denote the same units or data as those described with reference to FIG. 1 or FIG.

In this embodiment, the transmitting-side encrypted modulation device 10
The first key data 152 and the second key data 153 of 0 are the third key data 154 obtained from the transmitting-side key management device 300 by the first key encryption circuit 112 and the second key encryption circuit 113. The encrypted first key information 155 and the encrypted second key information 156 are added to the MPEG-TS time-division multiplexing circuit 201, where the same processing as in FIG. 2 is performed and transmitted. . The third key data 154 is applied to the FSK modulation circuit 801 and is digitally modulated as an FSK modulated wave signal 851, and is frequency-multiplexed with the 64QAM digital modulated wave signal 159 and the like via the signal synthesizing circuit 104 to be CATV transmitted. Output to the road 400.

On the other hand, in the receiving-side terminal device 500, the FSK modulated wave signal which has been frequency-multiplexed and transmitted is frequency-multiplexed and separated by the frequency-multiplexed signal separation circuit 501, and the frequency-multiplexed separated FSK modulated wave signal 852 is obtained. FSK demodulation is performed by the FSK demodulation circuit 802, and the third key data 853 is obtained. The third key data 853 allows the MPEG-TS demultiplexing circuit 20
The encrypted first key information 556 and the encrypted second key information 557 obtained in 3 are decrypted by the first key decryption circuit 507 and the second key decryption circuit 506, and the first key Data 560 and second key data 559 are obtained. Then, the first key data 560 and the second key data 559 are added to the content descrambling circuit 508, and the encrypted error-corrected digital data 555 is decrypted, and the descrambled digital data in the MPEG2 transport stream format is decoded. data
Returned to 561.

In the present embodiment, in addition to being able to fulfill the conditional access system of digital cable television broadcasting, the content scrambled by the operation result of the two types of key data of the first key data and the second key data is achieved. The first and second key information obtained by encrypting the video and audio data and the first key data and the second key data for performing content scrambling are time-division multiplexed to form a 64QAM digital modulated wave signal. Transmitted, and a third key for encrypting the first key data 152 as well as the second key data 153.
Since the key data 154 is transmitted as a FSK modulated wave signal as a downlink control line modulated wave signal, it is necessary to simultaneously decode the 64QAM digital modulated wave signal and the downlink control line modulated wave signal, which makes it difficult for eavesdropping. There are advantages.

FIG. 9 is a CAT for explaining the embodiment of the present invention.
FIG. 3 is a conceptual diagram illustrating a frequency arrangement of a V transmission path. In FIG. 9, 9001 is the entire downlink signal band, 9002 is a 64QAM digital modulated wave signal, and 9003 is a downlink control modulated signal such as a modulated wave signal. The figure shows an example of the transmission signal form of the CATV transmission line 400, in which a 64QAM digital modulated wave signal 9002 for transmitting scrambled video / audio data and third key data 154 are transmitted in the entire downlink signal band 9001. Multiple modulated wave signals are frequency-multiplexed, such as a downlink control line modulated wave signal 9003, a 64QAM digital modulated wave signal transmitting unscrambled video / audio data, and a modulated wave transmitting analog video / audio. .

FIG. 10 is a block diagram showing a configuration of a transmission apparatus of a conditional access system for a cable television according to another embodiment of the present invention and a configuration of the reception apparatus. In FIG.
1, FIG. 2, the same as the reference numerals shown in FIG. 7 or FIG. 8,
The same means or data as those described with reference to FIG. 1, FIG. 2, FIG. 7, or FIG.

In this embodiment, the transmitting-side encrypted modulation device 10
The first key data 152 of 0 is encrypted by the first key encryption circuit 112 with the third key data 154 obtained from the transmission side key etc. management device 300, and the second key data 153 is the second key data 153. The first key information 155 encrypted with the fourth key data 751 obtained from the transmission-side key etc. management device 300 by the encryption circuit 113 and the encrypted second key information 156 are MPEG-coded. It is added to the TS time-division multiplexing circuit 201, and the same processing as in FIG. 2 is performed and transmitted. The third key data 154 is applied to the FSK modulation circuit 801 and is digitally modulated and transmitted as the FSK modulated wave signal 851. The fourth key data 751 is stored in the information storage medium 513 such as an IC card and is delivered as described with reference to FIG. On the other hand, the receiving terminal device
In 500, the first key information 556 encrypted by the MPEG-TS demultiplexing circuit 203 is obtained by the first key decryption circuit 507,
The first key data 560 is obtained by being decrypted by the third key data 853 that has been FSK-demodulated by the SK demodulation circuit 802. The encrypted second key information 557 is sent to a second key decryption circuit 506 by a fourth key data 752 obtained from an information storage medium 513 such as an IC card.
And the second key data 559 is obtained. First
The key data 560 and the second key data 559 are added to the content descrambling circuit 508, and the encrypted error-corrected digital data 555 is decrypted and returned to the descrambled digital data 561 in the MPEG2 transport stream format. It is. In the present embodiment, the first key data 152 and the second key data 153 are provided in addition to being able to fulfill the conditional access system of digital cable television broadcasting.
The third key data 154 and the third key data
The first key information 155 and the second key information 156 that are encrypted using the two types of key data 751 and
The third key data 154 is transmitted as a downlink control line modulated wave signal such as an FSK modulated wave signal,
Since the key data 751 is distributed by the information storage medium 513, it is necessary to decode the 64QAM digital modulated wave signal, the downlink control line modulated wave signal, and the information storage medium, and there is an advantage that wiretapping is difficult.

In this embodiment, the third key data 154
Using the FSK modulated wave signal, the fourth key data 751 is described as being transmitted using the information storage medium, but the fourth key data 751 is transmitted using the FSK modulated wave signal, Key data 1
The same effect can be obtained by transmitting 54 using an information storage medium.

FIG. 11 is a block diagram showing a configuration of a transmission apparatus of a conditional access system for a cable television according to another embodiment of the present invention and a configuration of the reception apparatus. In FIG. 11, 854
Is FSK-demodulated fourth key data, which is shown in FIG. 1, FIG. 2, and FIG.
7, the same reference numerals as those shown in FIG. 8 or FIG.
The same means or data as those described with reference to FIG. 2, FIG. 7, FIG. 8, or FIG.

In this embodiment, the transmitting-side encrypted modulation device 10
The first key data 152 of 0 is encrypted by the first key encryption circuit 112 with the third key data 154 obtained from the transmission side key etc. management device 300, and the second key data 153 is the second key data 153. Encryption circuit 113
The fourth key data 75 obtained from the transmission-side key etc.
The encrypted first key information 155 and the encrypted second key information 156 are added to the MPEG-TS time-division multiplexing circuit 201 and transmitted after predetermined processing. number 3
Key data 154 and fourth key data 751 are FSK modulation circuits
801 and digitally modulated to produce an FSK modulated wave signal 85
Transmitted as 1. On the other hand, in the receiving terminal device 500, the encrypted second data obtained by the MPEG-TS demultiplexing circuit 203 is output.
The first key information 556 and the encrypted second key information 557 are
The first key decryption circuit 507 and the second key decryption circuit 506 generate FSK
The third key data 853 and the fourth key data 854 that have been FSK demodulated by the demodulation circuit 802 are decrypted by the first key data 560
In addition, second key data 559 is obtained. Thereafter, after a predetermined process, the data is returned to the descrambled digital data 561. In the present embodiment, in addition to being able to fulfill the conditional access system of digital cable television broadcasting, the first
Key data 152 and third key data 154 and fourth key data 751 as key data for encrypting the second key data 153.
The third key data 15
By transmitting the fourth and fourth key data 751 as FSK modulated wave signals, there is an advantage that an information storage medium and its delivery are not required, and a configuration for realization is simplified.

FIG. 12 is a block diagram showing a configuration of a transmission apparatus of a conditional access system for a cable television according to another embodiment of the present invention and a configuration of the reception apparatus. In FIG. 12, 861
Is FSK-modulated encrypted second key information, 862 is FSK-demodulated encrypted second key information, and the same codes as those shown in FIG. 1, FIG. 2 or FIG. The same means or data as those described with reference to FIG. 1, FIG. 2, or FIG.

In the present embodiment, the transmitting-side encrypted modulation device 10
The first key data 152 of 0 is encrypted by the first key encryption circuit 112 with the third key data 154 from the transmitting-side key etc. management device 300, and the encrypted first key information 155 is -The signal is added to the TS time-division multiplexing circuit 201, is subjected to predetermined processing, and is transmitted. No. 2
Key data 153 is encrypted by the second key encryption circuit 113 with the third key data 154 from the transmission-side key etc. management device 300, and the encrypted second key information 861 is encrypted by the FSK modulation circuit 801. Digitally modulated and transmitted as FSK modulated wave signal 851. The third key data 154 is stored in an information storage medium 513 such as an IC card and distributed.

On the other hand, in the receiving terminal device 500, the MPE
The encrypted first key information 556 obtained by the G-TS demultiplexing circuit 203 is used by the first key decryption circuit 507 by the third key data 558 obtained from the information storage medium 513 such as an IC card. The first key data 560 is obtained by decryption. FSK demodulation circuit 802
The encrypted second key information 862 demodulated in the second key decryption circuit 506 is decrypted by the third key data 558 obtained from the information storage medium 513 such as an IC card, and Data 559 is obtained. Thereafter, after a predetermined process, the data is returned to the descrambled digital data 561.

In the present embodiment, in addition to being able to fulfill the conditional access system of digital cable television broadcasting, the encrypted first key information 155 is transmitted in the MPEG-TS format, and the encrypted first key information 155 is transmitted. Key information 861 of 2 is FSK modulated wave signal
851 and the third key data 154 is stored in the information storage medium 5
Since the transmission is performed by using 13, the 64QAM digital modulated wave signal, the downlink control line modulated wave signal, and the information storage medium need to be decoded, and there is an advantage that eavesdropping is difficult.

FIG. 13 is a block diagram showing a configuration of a transmission apparatus of a conditional access system for a cable television according to another embodiment of the present invention and a configuration of the reception apparatus. In FIG.
1, 2, 7, 8, or 12 are the same as those shown in FIGS. 1, 2, 7, 8, or 12. Show.

In this embodiment, the transmitting-side encrypted modulation device 10
The first key data 152 of 0 is encrypted by the first key encryption circuit 112 with the third key data 154 obtained from the transmission side key etc. management device 300, and the encrypted first key information 155 Is added to the MPEG-TS time-division multiplexing circuit 201 and is transmitted after predetermined processing.
The second key data 153 is encrypted by the second key encryption circuit 113 with the fourth key data 751 obtained from the transmitting-side key etc. management device 300, and the encrypted second key information 861 is FSK Digitally modulated by modulation circuit 801 and transmitted as FSK modulated wave signal 851. The third key data 154 and the fourth key data 751
It is stored in an information storage medium 513 such as a C card and delivered.

On the other hand, in the receiving side terminal device 500, the MPE
The encrypted first key information 556 obtained by the G-TS demultiplexing circuit 203 is used by the first key decryption circuit 507 by the third key data 558 obtained from the information storage medium 513 such as an IC card. The first key data 560 is obtained by decryption. FSK demodulation circuit 802
The encrypted second key information 862 demodulated by the second key decryption circuit 506 is decrypted by a second key decryption circuit 506 using fourth key data 752 obtained from an information storage medium 513 such as an IC card. Data 559 is obtained. Thereafter, after a predetermined process, the data is returned to the descrambled digital data 561.

In the present embodiment, in addition to being able to fulfill the conditional access system of digital cable television broadcasting, the encrypted first key information 155 is transmitted in the MPEG-TS format, and the encrypted first key information 155 is transmitted. Key information 861 of 2 is FSK modulated wave signal
Since the third key data 154 and the fourth key data 751 are transmitted using the information storage medium 513,
Eavesdropping requires decoding the 64QAM digital modulated wave signal, the downlink control line modulated wave signal and the information storage medium, and has the advantage that eavesdropping is difficult, and the first key data 1
Since two types of the third key data 154 and the fourth key data 751 are used as the key data for encrypting the 52 and the second key data 153, there is also an advantage that it becomes more difficult to decipher the encryption.

FIG. 14 is a block diagram showing a configuration of a transmission apparatus of a conditional access system for a cable television according to another embodiment of the present invention and a configuration of the reception apparatus. In FIG.
The same reference numerals as those shown in FIG. 1, FIG. 2, FIG. 8 or FIG. 12 indicate the same units or data as those described with reference to FIG. 1, FIG. 2, FIG.

In this embodiment, the transmitting-side encrypted modulation device 10
The first key data 152 of 0 is encrypted by the first key encryption circuit 112 with the third key data 154 obtained from the transmission-side key etc. management device 300, and the encrypted first key information 155 is It is added to the MPEG-TS time-division multiplexing circuit 201 and transmitted after predetermined processing. The second key data 153 is encrypted by the second key encryption circuit 113 with the third key data 154 obtained from the transmission-side key etc. management device 300, and the encrypted second key information 861 is subjected to FSK modulation. Circuit 801
And is transmitted as an FSK modulated wave signal 851. Further, the third key data 154 is also digitally modulated by the FSK modulation circuit 801 and transmitted as the FSK modulated wave signal 851.

On the other hand, in the receiving terminal device 500, the MPE
The encrypted first key information 556 obtained by the G-TS demultiplexing circuit 203 is decrypted by the first key decryption circuit 507 by the third key data 853 demodulated by the FSK demodulation circuit 802, and the first key information 556 is decrypted. One key data 560 is obtained. The encrypted second key information 862 demodulated by the FSK demodulation circuit 802 is converted by the second key decryption circuit 506 into FS
The second key data 559 is obtained by being decrypted by the third key data 853 demodulated by the K demodulation circuit 802. Thereafter, after a predetermined process, the data is returned to the descrambled digital data 561.

In the present embodiment, in addition to being able to fulfill the conditional access system of digital cable television broadcasting, the encrypted first key information 155 is transmitted in the MPEG-TS format, and the encrypted first key information 155 is transmitted. Key information 861 of 2 is FSK modulated wave signal
Since it is transmitted as 851 and the third key data 154 is also transmitted as FSK modulated wave signal 851, it is necessary to decode 64QAM digital modulated wave signal and downlink control line modulated wave signal for eavesdropping, Since the encrypted second key information 861 and the third key data 154 are transmitted by the FSK modulated wave signal, the information storage medium and the delivery thereof are not required, and the configuration for realization is easy. There is an advantage of becoming.

FIG. 15 is a block diagram showing a configuration of a transmission apparatus of a conditional access system for a cable television according to another embodiment of the present invention and a configuration of the reception apparatus. In FIG.
1, 2, 7, 8, or 12 are the same as those shown in FIGS. 1, 2, 7, 8, or 12. Show.

In this embodiment, the transmitting-side encrypted modulation device 10
The first key data 152 of 0 is encrypted by the first key encryption circuit 112 with the third key data 154 obtained from the transmission side key etc. management device 300, and the encrypted first key information 155 Is added to the MPEG-TS time-division multiplexing circuit 201 and is transmitted after predetermined processing.
The second key data 153 is encrypted by the second key encryption circuit 113 with the fourth key data 751 obtained from the transmission-side key etc. management device 300, and the encrypted second key information is FSK-modulated. The signal is digitally modulated by a circuit 801 and transmitted as an FSK modulated wave signal 851.
The third key data 154 is also digitally modulated by the FSK modulation circuit 801 and transmitted as the FSK modulated wave signal 851. The fourth key data 751 is stored in an information storage medium 513 such as an IC card and delivered.

On the other hand, in the receiving side terminal device 500, the MPE
The encrypted first key information 556 obtained by the G-TS demultiplexing circuit 203 is decrypted by the first key decryption circuit 507 by the third key data 853 demodulated by the FSK demodulation circuit 802, and One key data 560 is obtained. The encrypted second key information 862 demodulated by the FSK demodulation circuit 802 is supplied to the second key decryption circuit 506 by an IC
Fourth key data obtained from information storage medium 513 such as a card
Decrypted by 752, second key data 559 is obtained.
In the present embodiment, in addition to being able to fulfill the conditional access system of digital cable television broadcasting, the encrypted first key information 155 is transmitted in the MPEG-TS format, and the encrypted second key information 155 is transmitted. Since the information 861 and the third key data are transmitted as the FSK modulated wave signal 851, and the fourth key data is transmitted using the information storage medium, the 64QAM digital modulated wave signal and the downlink control line signal are used for eavesdropping. It is necessary to decipher the modulated wave signal and the information storage medium, and there is an advantage that eavesdropping is difficult, and the first key data 152 and the second key data 1
Since two types of third key data 154 and fourth key data 751 are used as key data for encrypting 53, there is an advantage that it becomes more difficult to decipher the encryption.

FIG. 16 is a block diagram showing a configuration of a transmission apparatus of a conditional access system for a cable television according to another embodiment of the present invention and a configuration of the reception apparatus. In FIG.
1, FIG. 2, FIG. 7, FIG. 8, FIG. 11 or FIG. 12 are the same as those shown in FIG. 1, FIG. 2, FIG. 7, FIG. Shows the same data.

In this embodiment, the transmitting-side encrypted modulation device 10
The first key data 152 of 0 is encrypted by the first key encryption circuit 112 with the third key data 154 obtained from the transmission-side key etc. management device 300, and the encrypted first key information 155 is It is added to the MPEG-TS time-division multiplexing circuit 201 and transmitted after predetermined processing. The second key data 153 is encrypted by the second key encryption circuit 113 with the fourth key data 751 obtained from the transmission side key etc. management device 300, and the encrypted second key information 861 is subjected to FSK modulation. Circuit 801
And is transmitted as an FSK modulated wave signal 851. Further, the third key data 154 and the fourth key data 751 are also
FSK modulated wave signal 851 digitally modulated by FSK modulation circuit 801
Is transmitted as On the other hand, in the receiving terminal device 500, the encrypted second data obtained by the MPEG-TS demultiplexing circuit 203 is output.
The first key information 556 is the first key decryption circuit 507, and the FSK demodulation circuit 802
Is decrypted by the third key data 853 demodulated in
Key data 560 is obtained. The encrypted second key information 862 demodulated by the FSK demodulation circuit 802 is transmitted to the second key decryption circuit 506.
Then, the second key data 559 is obtained by being decrypted by the fourth key data 854 demodulated by the FSK demodulation circuit 802. Then, after a predetermined process, the descrambling digital data 56
Returned to 1.

In the present embodiment, in addition to being able to fulfill the conditional access system of digital cable television broadcasting, the encrypted first key information 155 is transmitted in the MPEG-TS format, and the encrypted first key information 155 is transmitted. Since the second key information 861, the third key data and the fourth key data are transmitted as the FSK modulated wave signal 851, the 64QAM digital modulated wave signal and the downlink control line modulated wave signal are decoded for eavesdropping. The second key information 86 which has the advantage of requiring
By transmitting the first and third key data 154 and the fourth key data 751 as FSK modulated wave signals, there is an advantage that an information storage medium and its delivery become unnecessary, and a configuration for realization becomes easy.

In the embodiment described with reference to FIGS. 11 to 16, the encrypted first key information 155 is transmitted in the MPEG-TS format, and the encrypted second key information Wave signal 8
Although described as transmitting at 51, the encrypted first key information 155 is transmitted as the FSK modulated wave signal 851, and the encrypted second key information 861 is transmitted in the MPEG-TS format. Has the same effect.

FIG. 17 is a block diagram showing the configuration of one embodiment of the key encryption circuit of the present invention. 17, 1701 is a key encryption circuit, 1751 is input key data, 1752 is encrypted key information, and 1753 is input key data. The key encryption circuit 1701, input key data 1751, encrypted key information 1752
And the input key data 1753, the first key encryption circuit 112,
It corresponds to the first key data 152, the encrypted first key information 155, and the third key data 154.

The key encryption circuit 1701 is connected to the receiving terminal 500
In order to generate encrypted key information 1752, the input key data 1751
And the input key data 1753. Fig. 17
In the example described in, the 64-bit input key data 1751 and the 1-bit input key data 1753 use 4-bit encrypted key information 1
752. The input key data 1751 is "0011 ... 1001",
If the input key data 1753 is “1”, the encrypted key information 1752 is output as “0001”. If the input key data 1751 is “1001... 1001” and the input key data 1753 is “0”, the encrypted key information 1752 is output as “0011”.

It should be noted that even if the encrypted key information 1752 is eavesdropped and "0011" is found, the input key data 1753 is "1" and the input key data 1753 is "0".
Since 51 is different, safety will be ensured.

In the present embodiment, in addition to being able to fulfill the key encryption circuit of the conditional access system of digital cable television broadcasting, the encrypted key information 1752 is compared with the input key data 1751 and the input key data 1753. Since the processing can be performed, there is an advantage that the configuration is easy to realize the key encryption circuit and an advantage that the number of bits of the key information to be transmitted can be reduced.

In this embodiment, the number of bits of input key data is 64 bits and 1 bit, and the number of bits of encrypted key information is 4 bits. However, the number of bits is not limited to these. is not.

FIG. 18 is a block diagram showing the configuration of one embodiment of the key decryption circuit of the present invention. In FIG. 18, reference numeral 1801 denotes a key decryption circuit, 1851 denotes input of encrypted key information, 1852 denotes output of decrypted key data, and 1853 denotes input of key data. Note that the key decryption circuit 1801, the encrypted key information input 1851, the decrypted key data output 1852, and the key data input 1853
Is the first key decryption circuit 507, the encrypted first key information 55
6, and corresponds to the first key data 560 and the third key data 558.

The key decryption circuit 1801 performs processing based on the encrypted key information input 1851 and the internal information stored in the key data input 1853 in order to generate a decrypted key data output 1852.
A so-called table lookup process is performed. In the example shown in FIG. 18, a 64-bit decrypted key data output 1852 is obtained by a 4-bit encrypted key information input 1851 and a 1-bit key data input 1853. When the encrypted key information input 1851 becomes "00
01 "and the key data input 1853 is" 1 ", the decrypted key data output 1852 is output as" 0011 ... 1001 ".
Encrypted key information input 1851 is "0011", key data input
If 1853 is “0”, the decrypted key data output 1852 is output as “1001... 1001”.

In the present embodiment, in addition to being able to fulfill the key decryption circuit of the conditional access system for digital cable television broadcasting, the 4-bit encrypted key information input 1851 and the 1-bit key Since a 64-bit decrypted key data output 1852 can be obtained at the data input 1853, there is an advantage that the configuration is easy to realize a key decryption circuit and that the number of bits of key information to be transmitted can be reduced.

In this embodiment, the number of bits of the encrypted key information input is 4 bits, the number of bits of the key data input is 1 bit, and the number of bits of the decrypted key data output is 6 bits.
Although described as four bits, the number of bits is not limited to these.

[0077]

According to the present invention, data scrambled by a plurality of key data is transmitted as a 64QAM digital modulated wave signal, and a plurality of encrypted key data for descrambling and decryption are decrypted. Key data is obtained from a 64QAM digital modulated wave signal, an information storage medium such as an IC card or an IC memory, or an FSK digital modulated wave signal. The data can be descrambled, and information such as video and audio of the contracted channel can be obtained. However, if a viewer tries to watch a channel to which they have not subscribed,
Since there is no C card, there is no necessary data in the IC memory, or there is no means for obtaining the key data, the key data cannot be obtained, so that the scrambled data cannot be descrambled. , Can not get information. In other words, it is possible to use a conditional access system for digital cable television broadcasting with a simple configuration and considerable security.

As described above, the present invention is an extremely effective technique capable of providing a conditional access system for digital cable television broadcasting.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a conditional access system transmission apparatus for a cable television according to an embodiment of the present invention and a configuration of the reception apparatus.

FIG. 2 is a block diagram showing a configuration of a transmission apparatus of a conditional access system for a cable television according to another embodiment of the present invention and a configuration of the reception apparatus.

FIG. 3 is a block diagram showing a configuration of scrambling in the embodiment of the present invention.

FIG. 4 is a block diagram illustrating a configuration of a MULTI2 encryption device according to an embodiment of the present invention.

FIG. 5 is a conceptual diagram showing a signal configuration of an MPEG2 transport stream format for describing an embodiment of the present invention.

FIG. 6 is a conceptual diagram showing a signal configuration of a packet header in an MPEG2 transport stream format for describing an embodiment of the present invention.

FIG. 7 is a block diagram showing a configuration of a transmission apparatus of a conditional access system for a cable television according to another embodiment of the present invention and a configuration of the reception apparatus.

FIG. 8 is a block diagram showing a configuration of a transmission apparatus of a conditional access system for a cable television according to another embodiment of the present invention and a configuration of the reception apparatus.

FIG. 9 is a conceptual diagram showing a frequency arrangement of a CATV transmission line for describing an embodiment of the present invention.

FIG. 10 is a block diagram showing a configuration of a transmission apparatus of a conditional access system for a cable television according to another embodiment of the present invention and a configuration of the reception apparatus.

FIG. 11 is a block diagram illustrating a configuration of a transmission apparatus of a conditional access system for a cable television according to another embodiment of the present invention and a configuration of the reception apparatus.

FIG. 12 is a block diagram illustrating a configuration of a transmission apparatus using a conditional access system of a cable television according to another embodiment of the present invention and a configuration of the reception apparatus.

FIG. 13 is a block diagram showing a configuration of a transmission apparatus of a conditional access system for a cable television according to another embodiment of the present invention and a configuration of the reception apparatus.

FIG. 14 is a block diagram illustrating a configuration of a conditional access system transmitting apparatus for a cable television and a receiving apparatus according to another embodiment of the present invention.

FIG. 15 is a block diagram illustrating a configuration of a transmission apparatus using a conditional access system of a cable television according to another embodiment of the present invention and a configuration of the reception apparatus.

FIG. 16 is a block diagram showing a configuration of a transmission apparatus of a conditional access system for a cable television according to another embodiment of the present invention and a configuration of the reception apparatus.

FIG. 17 is a block diagram showing a configuration of an embodiment of a key encryption circuit of the present invention.

FIG. 18 is a block diagram showing a configuration of one embodiment of a key decryption circuit of the present invention.

[Explanation of symbols]

 100: transmitting-side encryption modulator 200: transmitting-side video signal source device 300: transmitting-side key etc. management device 400: CATV transmission line 500: receiving-side terminal device 600: video / audio output device 101: encryption device 102: time division Multiplexing circuit 111: Data multiplexing and content scrambling circuit 112: First key encryption circuit 113: Second key encryption circuit 201: MPEG-TS time division multiplexing circuit 202: Content scrambling circuit 203: MPEG-TS demultiplexing Circuit 503 64QAM demodulation circuit 505 Key data separation circuit 506 Second key decryption circuit 507 First key decryption circuit 508 Content descramble circuit 509 MPEG demultiplexing circuit 513 Information storage medium

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H04N 7/081 H04N 7/13 Z 7/24 7/167 Z 7/167 (72) Inventor Moriyoshi Akiyama 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Pref.Hitachi, Ltd. Multimedia System Development Headquarters (72) Inventor Tomotake Sato 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Pref. Hitachi, Ltd. Multimedia System Development Headquarters (72) Inventor Masami Nishida 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture Inside the Hitachi, Ltd.Video Information Media Division (72) Inventor Daikan Tanaka 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Pref. Media Division (72) Inventor Tohru Yamada 216 Totsuka-cho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture Hitachi, Ltd. (72) Inventor Toshiyuki Tanaka 216 Totsukacho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture, Japan Space Technology Development Headquarters, Hitachi, Ltd.

Claims (28)

[Claims] A scramble operation is performed by using operation results of two types of key data of a first key data and a second key data in order to scramble a part of digital data in an mpeg transport stream format. Content scrambling means, first key data encrypting means in which the first key data and third key data are arithmetically processed to encrypt the first key data, and the second key A second key data encrypting unit in which the second key data and the third key data are arithmetically processed to encrypt data; an output data stream of the content scramble unit and the first key data Multiplexing means for time-division multiplexing the output data of the encryption means and the output data of the second key data encryption means in the form of an MPEG transport stream; Modulation means for digitally modulating the output of the third key data, such as multi-valued QAM, etc .; information storage means, such as a semiconductor memory or an IC card capable of storing the third key data; A signal synthesizing means for frequency-multiplexing the modulated wave and transmitting the modulated wave to a transmission line. 2. A scrambling operation using an operation result of two types of key data of a first key data and a second key data in order to scramble a part of digital data in an mpeg transport stream format. Content scrambling means, first key data encrypting means in which the first key data and third key data are arithmetically processed in order to encrypt the first key data, and the second key A second key data encrypting unit in which the second key data and the fourth key data are arithmetically processed to encrypt data; an output data stream of the content scramble unit and the first key data Multiplexing means for time-division multiplexing the output data of the encryption means and the output data of the second key data encryption means in the MPPEG transport stream format; A modulating means for digitally modulating the output of the second key, such as a multi-valued QAM such as 64 values; an information storage means such as a semiconductor memory or an IC card capable of storing the third key data and the fourth key data; And a signal synthesizing unit for frequency-multiplexing a plurality of modulated waves including the output of (1) and transmitting the multiplexed waves to a transmission path. 3. A scrambling operation is performed by using an operation result of two types of key data of a first key data and a second key data in order to scramble a part of digital data in an mpeg transport stream format. Content scrambling means, first key data encrypting means in which the first key data and third key data are arithmetically processed to encrypt the first key data, and the second key A second key data encrypting unit in which the second key data and the third key data are arithmetically processed to encrypt data; an output data stream of the content scramble unit and the first key data Multiplexing means for time-division multiplexing the output data of the encryption means and the output data of the second key data encryption means in the form of an MPEG transport stream; First modulation means for digitally modulating the output of the third key data such as multi-level QAM such as 64 values, second modulation means for digitally modulating the third key data such as FSK, and output of the first modulation means And a signal synthesizing unit for frequency-multiplexing a plurality of modulated waves including the output of the second modulating unit and transmitting the multiplexed wave to a transmission path. 4. A scrambling operation is performed using an operation result of two types of key data of a first key data and a second key data in order to scramble a part of digital data in an mpeg transport stream format. Content scrambling means, first key data encrypting means in which the first key data and third key data are arithmetically processed in order to encrypt the first key data, and the second key A second key data encrypting unit in which the second key data and the fourth key data are arithmetically processed to encrypt data; an output data stream of the content scramble unit and the first key data Multiplexing means for time-division multiplexing the output data of the encryption means and the output data of the second key data encryption means in the MPPEG transport stream format; A first modulating means for digitally modulating the output of the multi-level QAM such as 64 values, and information such as a semiconductor memory or an IC card capable of storing either the third key data or the fourth key data. Storage means, second modulation means for digitally modulating another one of the third key data and the fourth key data with FSK or the like, output of the first modulation means and the second modulation means And a signal synthesizing unit for frequency-multiplexing a plurality of modulated waves including the output of (1) and transmitting the multiplexed waves to a transmission path. 5. A scrambling operation using an operation result of two types of key data of a first key data and a second key data in order to scramble a part of digital data in an mpeg transport stream format. Content scrambling means, first key data encrypting means in which the first key data and third key data are arithmetically processed to encrypt the first key data, and the second key A second key data encrypting unit in which the second key data and the fourth key data are arithmetically processed to encrypt data; an output data stream of the content scramble unit and the first key data Multiplexing means for time-division multiplexing the output data of the encryption means and the output data of the second key data encryption means in the form of an MPEG transport stream; A first modulating means for digitally modulating, such as multi-level QAM outputs such 64 values, both of the third key data and the fourth key data
A second modulating means for digitally modulating the FSK, and a signal synthesizing means for frequency-multiplexing a plurality of modulated waves including an output of the first modulating means and an output of the second modulating means and transmitting the modulated waves to a transmission path A transmission device comprising: 6. A scrambling operation using an operation result of two types of key data of a first key data and a second key data in order to scramble a part of digital data in an mpeg transport stream format. Content scrambling means, first key data encrypting means in which the first key data and third key data are arithmetically processed in order to encrypt the first key data, and the second key A second key data encrypting unit in which the second key data and the third key data are arithmetically processed to encrypt data; an output data stream of the content scramble unit and the first key data Multiplexing means for time-division multiplexing either the output data of the encryption means or the output data of the second key data encryption means in the MPPEG transport stream format, First modulation means for digitally modulating the output of the multiplexing means such as multi-valued QAM such as 64 values; information storage means such as a semiconductor memory or an IC card capable of storing the third key data; The other one of the output data of the key data encryption means and the output data of the second key data encryption means
A second modulating means for digitally modulating the FSK, and a signal synthesizing means for frequency-multiplexing a plurality of modulated waves including an output of the first modulating means and an output of the second modulating means and transmitting the modulated waves to a transmission path A transmission device comprising: 7. A scrambling operation is performed using an operation result of two types of key data of a first key data and a second key data in order to scramble a part of digital data in an mpeg transport stream format. Content scrambling means, first key data encrypting means in which the first key data and third key data are arithmetically processed to encrypt the first key data, and the second key A second key data encrypting unit in which the second key data and the fourth key data are arithmetically processed to encrypt data; an output data stream of the content scramble unit and the first key data Multiplexing means for time-division multiplexing one of the output data of the encryption means and the output data of the second key data encryption means in the MPPEG transport stream format, First modulation means for digitally modulating the output of the multiplexing means, such as multi-valued QAM such as 64 values, and information such as a semiconductor memory or an IC card capable of storing the third key data and the fourth key data Storage means, the other of the output data of the first key data encryption means and the other of the output data of the second key data encryption means
A second modulating means for digitally modulating the FSK, and a signal synthesizing means for frequency-multiplexing a plurality of modulated waves including an output of the first modulating means and an output of the second modulating means and transmitting the modulated waves to a transmission path A transmission device comprising: 8. A scrambling operation using an operation result of two types of key data of a first key data and a second key data in order to scramble a part of digital data in an mpeg transport stream format. Content scrambling means, first key data encrypting means in which the first key data and third key data are arithmetically processed to encrypt the first key data, and the second key A second key data encrypting unit in which the second key data and the third key data are arithmetically processed to encrypt data; an output data stream of the content scramble unit and the first key data Multiplexing means for time-division multiplexing one of the output data of the encryption means and the output data of the second key data encryption means in the MPPEG transport stream format, First modulation means for digitally modulating the output of the multiplexing means such as multi-valued QAM such as 64 values, output data of the first key data encryption means and the second
The other one of the output data of the key data encryption means and the second modulation means for digitally modulating the third key data such as FSK, the output of the first modulation means and the second modulation means A signal synthesizing means for frequency-multiplexing a plurality of modulated waves including an output and transmitting the multiplexed waves to a transmission path. 9. A scrambling operation is performed using an operation result of two types of key data of a first key data and a second key data in order to scramble a part of digital data in an mpeg transport stream format. Content scrambling means, first key data encrypting means in which the first key data and third key data are arithmetically processed in order to encrypt the first key data, and the second key A second key data encrypting unit in which the second key data and the fourth key data are arithmetically processed to encrypt data; an output data stream of the content scramble unit and the first key data Multiplexing means for time-division multiplexing one of the output data of the encryption means and the output data of the second key data encryption means in the MPPEG transport stream format, A first modulating means for digitally modulating the output of the multiplexing means such as multi-valued QAM such as 64 values, and a semiconductor memory or IC capable of storing either the third key data or the fourth key data. Information storage means such as a card, and the other one of the output data of the first key data encryption means and the output data of the second key data encryption means, the third key data, and the fourth key A second modulator for digitally modulating another one of the data, such as FSK, and a frequency multiplexing method for a plurality of modulated waves including an output of the first modulator and an output of the second modulator, and a transmission path. And a signal synthesizing means for transmitting the signal to the transmitter. 10. A scrambling operation using an operation result of two types of key data of a first key data and a second key data in order to scramble a part of digital data in an mpeg transport stream format. Content scrambling means, first key data encrypting means in which the first key data and third key data are arithmetically processed to encrypt the first key data, and the second key A second key data encrypting unit in which the second key data and the fourth key data are arithmetically processed to encrypt data; an output data stream of the content scramble unit and the first key data Multiplexing means for time-division multiplexing either the output data of the encryption means or the output data of the second key data encryption means in the MPPEG transport stream format; A first modulating means for digitally modulating the output of the multiplexing means, such as multi-valued QAM such as 64 values, and an output data of the first key data encrypting means and A second modulator for digitally modulating both the other one of the output data and the third key data and the fourth key data, such as FSK, an output of the first modulator and the second modulation A signal synthesizing unit for frequency-multiplexing a plurality of modulated waves including the output of the unit and transmitting the multiplexed wave to a transmission path. 11. The transmitting device according to claim 1, wherein said first key data encrypting means includes means for transmitting said first key data such as a number code corresponding to said first key data. A transmitting apparatus for performing a process of assigning a unique data code for each of the data and outputting the data as output data of the first key data encrypting means. 12. The transmitting device according to claim 1, wherein said second key data encrypting means includes means for transmitting said second key data such as a number code corresponding to said second key data. A transmitting device for performing a process of assigning a unique data code for each of the data and outputting the data as output data of the second key data encrypting means. 13. A demodulation means for demodulating a digital modulated wave such as a multi-valued QAM such as 64-values transmitted by frequency multiplexing, and time-division multiplexed in an mpeg transport stream format which is an output of said demodulation means. Time-division multiplexing / demultiplexing means for separating the content-scrambled data from the data and the encrypted first key data information and the encrypted second key data information, and the third key data are stored. An information storage means such as a semiconductor memory or an IC card; and the encrypted
First key data decoding means for decoding information of one key data into first key data by means of the third key data stored in the information storage means, obtained by the time division demultiplexing means; The above encrypted
Second key data decryption means for decrypting the information of the second key data into second key data using the third key data stored in the information storage means, and the first key data decryption means. Using the obtained first key data and the second key data obtained by the second key data decrypting means, digital data in a transport stream format is obtained from the content-scrambled data obtained by the demodulating means. A receiving device comprising a descrambling means. 14. A demodulation means for demodulating a digital modulated wave such as a multi-valued QAM such as 64-values transmitted in a frequency multiplexed manner, and time-division multiplexed in an MPPEG transport stream format which is an output of said demodulation means. Time-division demultiplexing means for separating the content-scrambled data from the data and the information of the encrypted first key data and the information of the encrypted second key data, a third key data and a fourth Information storage means such as a semiconductor memory or an IC card in which key data is stored; and the encrypted second data obtained by the time division demultiplexing means.
First key data decoding means for decoding information of one key data into first key data by means of the third key data stored in the information storage means, obtained by the time division demultiplexing means; The above encrypted
Second key data decryption means for decrypting the information of the second key data into second key data using the fourth key data stored in the information storage means, and the first key data decryption means. Using the obtained first key data and the second key data obtained by the second key data decrypting means, digital data in a transport stream format is obtained from the content-scrambled data obtained by the demodulating means. A receiving device comprising a descrambling means. 15. A first demodulation means for demodulating a frequency-multiplexed and transmitted digital modulated wave such as a multi-valued QAM such as 64 values, and a frequency-multiplexed and transmitted digital modulated wave such as FSK. Second demodulating means for demodulating to obtain third key data, and content scrambled data encrypted from time-division multiplexed data in the MPPEG transport stream format which is the output of the first demodulating means. Time-division multiplexing / demultiplexing means for separating the information of the first key data and the information of the encrypted second key data; and
The information of the key data of 1 is obtained by the third demodulation means obtained by the second demodulation means.
First key data decrypting means for decrypting the first key data with the key data of the above, and the encrypted
The information of the second key data is obtained by the third demodulation means obtained by the second demodulation means.
Second key data decrypting means for decrypting the second key data with the first key data, and the first key data obtained by the first key data decrypting means and the second key data decrypting means A descrambling means for obtaining digital data in a transport stream format from the content-scrambled data obtained by the first demodulation means using the obtained second key data. 16. A first demodulation means for demodulating a digital modulated wave such as a multi-valued QAM such as 64 values transmitted by frequency multiplexing, and a digital modulated wave such as FSK transmitted by frequency multiplexing. A second demodulation means for demodulating to obtain either the third key data or the fourth key data, and time-division multiplexed data in an mpeg transport stream format which is an output of the first demodulation means. Time-division multiplexing / demultiplexing means for separating the content-scrambled data from the encrypted first key data information and the encrypted second key data information, third key data and the fourth key An information storage means such as a semiconductor memory or an IC card in which one of the data is stored; and the encrypted second data obtained by the time division demultiplexing means.
The information of the first key data is stored in the information storage means or the second
First key data decryption means for decrypting the first key data by the third key data obtained by one of the demodulation means, and the encrypted second key data obtained by the time division demultiplexing means.
The information of the second key data is stored in the information storage means or the second
Second key data decoding means for decoding into second key data by the fourth key data obtained by one of the demodulation means, and the first key data obtained by the first key data decoding means Key data and descrambling means for obtaining transport stream format digital data from the content-scrambled data obtained by the first demodulation means by the second key data obtained by the second key data decoding means. A receiving device comprising: 17. A first demodulation means for demodulating a digital modulated wave such as a multi-valued QAM such as 64-values transmitted in a frequency multiplexed manner, and a digital modulated wave such as FSK transmitted in a frequency multiplexed manner. Second demodulation means for demodulating to obtain third key data or fourth key data, and content scrambled from the time-division multiplexed data in the MPPEG transport stream format which is the output of the first demodulation means. Time-division multiplexing / demultiplexing means for separating data and information of the encrypted first key data as well as the information of the encrypted second key data; and No.
The information of the key data of 1 is obtained by the third demodulation means obtained by the second demodulation means.
First key data decrypting means for decrypting the first key data with the key data of the above, and the encrypted
The information of the second key data is obtained by the fourth demodulation means.
Second key data decrypting means for decrypting the second key data with the first key data, and the first key data obtained by the first key data decrypting means and the second key data decrypting means A descrambling means for obtaining digital data in a transport stream format from the content-scrambled data obtained by the first demodulation means using the obtained second key data. 18. A first demodulating means for demodulating a digital modulated wave such as a multi-valued QAM such as 64 values transmitted by frequency multiplexing, and a digital modulated wave such as FSK transmitted by frequency multiplexing. Second demodulation means for obtaining either the information of the first key data demodulated and encrypted or the information of the encrypted second key data, and empeg which is an output of the first demodulation means. Time division for separating any one of the content scrambled data, the encrypted first key data information, and the encrypted second key data information from the time division multiplexed data in the transport stream format Demultiplexing means; information storage means such as a semiconductor memory or an IC card in which third key data is stored; and the cipher obtained by either the time-division demultiplexing means or the second demodulating means. It has been first key data of the information the third stored in the information storage means
First key data decrypting means for decrypting the first key data by the key data of the above, the encrypted second obtained by one of the time-division demultiplexing means or the second demodulation means The information of the key data is stored in the third information storage means.
Second key data decrypting means for decrypting the second key data with the first key data, and the first key data obtained by the first key data decrypting means and the second key data decrypting means A descrambling means for obtaining digital data in a transport stream format from the content-scrambled data obtained by the first demodulation means using the obtained second key data. 19. A first demodulating means for demodulating a frequency-multiplexed and transmitted digital modulated wave such as a multi-level QAM such as 64-value, and a frequency-multiplexed and transmitted digital modulated wave such as FSK. A second demodulation means for obtaining either the information of the first key data demodulated and encrypted or the information of the encrypted second key data, and empeg which is an output of the first demodulation means. Time division for separating one of the content scrambled data, the encrypted first key data information and the encrypted second key data information from the time division multiplexed data in the transport stream format A demultiplexing unit; an information storage unit such as a semiconductor memory or an IC card in which the third key data and the fourth key data are stored; and one of the time division demultiplexing unit and the second demodulation unit. The information of the encrypted first key data obtained in the third method is stored in the information storage means.
First key data decryption means for decrypting the first key data by the key data of the above, the encrypted second obtained by either the time division demultiplexing means or the second demodulation means The information of the key data is stored in the information storage unit.
Second key data decrypting means for decrypting the second key data with the first key data, and the first key data obtained by the first key data decrypting means and the second key data decrypting means A descrambling means for obtaining digital data in a transport stream format from the content-scrambled data obtained by the first demodulation means using the obtained second key data. 20. A first demodulation means for demodulating a digitally modulated wave such as a multi-valued QAM such as 64 values transmitted in a frequency multiplexed manner, and a digital modulated wave such as FSK transmitted in a frequency multiplexed manner. Second demodulating means for obtaining either one of the information of the first key data demodulated and encrypted and the information of the encrypted second key data and the third key data, the first demodulation Either the content-scrambled data and the encrypted first key data information or the encrypted second key data information from the time-division multiplexed data in the MPPEG transport stream format output from the means. Time-division multiplexing / demultiplexing means for separating one, and the second demodulation information of the encrypted first key data obtained by either the time-division multiplexing / demultiplexing means or the second demodulation means. No. obtained by means First key data decrypting means for decrypting the first key data by the third key data, and the encrypted second data obtained by either the time division multiplexing / demultiplexing means or the second demodulating means. Second key data decoding means for decoding the information of the key data into second key data with the third key data obtained by the second demodulation means, and obtained by the first key data decoding means. The content data scrambled data obtained by the first demodulation means by the first key data and the second key data obtained by the second key data decryption means, And a descrambling means for obtaining the following. 21. A first demodulating means for demodulating a digital modulated wave such as a multi-valued QAM such as 64 values transmitted in a frequency multiplexed manner, and a digital modulated wave such as FSK transmitted in a frequency multiplexed manner. The second to obtain either the information of the first key data that has been demodulated and encrypted and the information of the second key data that has been encrypted and one of the third key data and the fourth key data. Demodulation means, information of the content-scrambled data and the encrypted first key data from the time-division multiplexed data in the MPPEG transport stream format, which is the output of the first demodulation means, and the encrypted first key data. Time-division multiplexing / demultiplexing means for separating one of the information of the second key data; and information storage of a semiconductor memory or an IC card in which either the third key data or the fourth key data is stored. Means, the information of the encrypted first key data obtained by either the time-division multiplexing / demultiplexing means or the second demodulation means, either the information storage means or the second demodulation means. On the other hand, the first key data
First key data decrypting means for decrypting to the key data of the above, the information of the encrypted second key data obtained by either the time division demultiplexing means or the second demodulation means The second key data obtained by either the information storage means or the second demodulation means is used for the second key data.
A second key data decrypting means for decrypting to the key data, the first key data obtained by the first key data decrypting means and the second key data obtained by the second key data decrypting means A receiving device comprising: descrambling means for obtaining transport stream format digital data from the content scrambled data obtained by the first demodulation means using key data. 22. A first demodulation means for demodulating a digital modulated wave such as a multi-valued QAM such as 64 values transmitted by frequency multiplexing, and a digital modulated wave such as FSK transmitted by frequency multiplexing. Second demodulating means for obtaining information of the first key data encrypted by demodulation and either one of the information of the encrypted second key data and the third key data and the fourth key data. The information of the content-scrambled data and the encrypted first key data from the time-division multiplexed data in the MPPEG transport stream format, which is the output of the first demodulation means, and the encrypted second key Time-division multiplexing / demultiplexing means for separating one of data information, and information on the encrypted first key data obtained by one of the time-division multiplexing / demultiplexing means or the second demodulation means The above second First key data decrypting means for decrypting the first key data by the third key data obtained by the keying means, and one of the time-division multiplexing / demultiplexing means or the second demodulating means. Second key data decoding means for decoding the information of the encrypted second key data into second key data with fourth key data obtained by the second demodulation means, From the first key data obtained by the key data decoding means and the content scrambled data obtained by the first demodulation means by the second key data obtained by the second key data decoding means, A descrambling means for obtaining digital data in a transport stream format. 23. The receiving apparatus according to claim 13, wherein said first key data decrypting means includes a data code such as a number code which is information of said encrypted first key data. The call processing is performed according to
A receiving device characterized by obtaining key data of: 24. The receiving apparatus according to claim 13, wherein said second key data decrypting means includes a data code such as a number code which is information of said encrypted second key data. Call processing according to the above second
A receiving device characterized by obtaining key data of: 25. A transmitting apparatus for multiplexing and modulating digital data and transmitting the modulated data through a transmission path, scrambles data relating to a program content among the digital data by calculating a plurality of key data, and encrypts the plurality of key data. A transmission device characterized in that the data is distributed without scrambling. 26. A receiving apparatus for receiving digital data via a transmission path and separating and demodulating the digital data, wherein the decryption and extraction of a plurality of encrypted key data are performed, and the operation of the plurality of key data is performed to obtain the digital data. A receiving device for descrambling data on scrambled program contents. 27. A receiving apparatus for receiving digital data via a transmission path and separating and demodulating the digital data, comprising decoding and extracting a plurality of encrypted key data, and calculating the plurality of key data, A receiving apparatus for descrambling data on scrambled program contents and outputting data on the descrambled program contents. 28. A transmitting apparatus for multiplexing and modulating digital data and transmitting the modulated data via a transmission path, scrambles data relating to the program contents of the digital data by calculating a plurality of key data, and encrypts the plurality of key data. A transmitter that distributes digital data without scrambling, and a receiver that receives and separates and demodulates digital data via a transmission path, decrypts and extracts a plurality of encrypted key data, and A transmission / reception system comprising a plurality of receiving devices for descrambling data on program contents scrambled among digital data by calculation and outputting data on descrambled program contents.