JP2002171504A - Digital broadcast device, digital broadcast receiver and a digital broadcast system comprising them, and computer-readable recoding medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a digital broadcast system that transmits an encrypted control program to each digital broadcast receiver. SOLUTION: A digital broadcast device 100 stores the same control program as that used to control each digital broadcast receiver 110 to a program DB 102 and stores a new control program whose version is upgraded to a new program DB 103. An encryption processing section 105 encrypts the new control program by using part data of the control program. A modulation section 107 multiplexes the encrypted new control program and transmits the multiplexed program. A TS decoder section 112 of the digital broadcast receiver 110 demultiplexes downloaded data including the encrypted new control program from a received TS. A CPU 118 informs an encryption decoding section 115 about the data of the control program stored in a nonvolatile memory 116 and the section 115 decodes the encrypted new control program by using the data for a decoding key.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digital broadcasting apparatus and a digital broadcasting receiving apparatus for securely transmitting and receiving program data in digital broadcasting, and a digital broadcasting system comprising the same.

[0002]

2. Description of the Related Art According to the MPEG2 standard currently used in most digital broadcasting, video, audio, and the like are packetized in accordance with respective regulations, then time-division multiplexed on a transport stream, and transmitted to a receiving device. . Each receiving device separates necessary packets such as video and audio from the received transport stream and performs decoding.

[0003] In recent years, services have been diversified in digital broadcasting, and not only video and audio but also data broadcasting have been performed. In order to realize diversified services, it is necessary for the receiving device to update to an operation program that can support the service each time a service is added or changed, and to respond to such changes in real time. Is required. In order to satisfy this demand, recent digital broadcasting systems transmit a control program for controlling the operation of the receiving device from the broadcasting device,
The receiving device has a control program update function that can receive the control program and automatically operate with the new control program.
There is one described in Japanese Patent No. 4451.

[0004] Regarding a conventional control program updating method,
This will be described with reference to FIG. FIG. 9 is a configuration diagram of a conventional broadcast receiving device in a digital broadcasting system. In the broadcast receiving device, a broadcast signal transmitted from the broadcast device is input to a demodulation unit 901, subjected to demodulation processing, and input as a transport stream bit sequence to a TS (transport stream) decoder 902. The TS decoder 902 selects and separates necessary packets from the input transport stream, and outputs video packets to the video output unit 903 and audio packets to the audio output unit 904.
And outputs the data packet to the CPU 905. The video output unit 903 converts a video packet input from the TS decoder 902 into a signal that can be displayed on a general TV receiver or monitor. The audio output unit 904
The audio packet input from the TS decoder 902 is converted into an analog audio signal and output to a speaker.

The CPU 905 normally performs a control operation according to a control program stored in a nonvolatile memory 906 such as a flash memory. For example, according to the input from the user interface unit 907, the TS decoder 9
For example, when a data packet input from the TS decoder 902 is additional service information such as a program guide, a control operation is performed according to the information. However, if the input data packet is a new control program, the data packet is temporarily stored in the RAM 908, and it is determined whether the data is normal. The program is written into the nonvolatile memory 906. After the above operations are completed normally, the CPU 905
Sends a reset instruction to the reset circuit 909, and the broadcast receiving apparatus starts operation with the rewritten new control program. This allows the broadcast receiving apparatus to respond to the addition or change of the service in real time.

[0006]

By the way, when program data is transmitted from a broadcasting device to each broadcast receiving device, the program data flows in a wide range, so that an unrelated third party can easily execute the program data. Can be obtained. Therefore, information leakage or falsification of program data can be easily performed, and it is desired to secure security by some method.

However, in the conventional program updating method, a program sent from a broadcasting device is
At present, security is not considered in particular.
Also, even if the program has a security function in some way, it is necessary to store data for releasing the security in advance in the broadcast receiving device, and the data cannot be easily changed.
There is a problem that the security method is simplified.

An object of the present invention is to provide a digital broadcasting system which can solve such problems and can enhance the confidentiality of program data transmitted from a broadcasting device and does not simplify the method. And

[0009]

According to the present invention, there is provided a digital broadcasting system comprising a digital broadcasting apparatus and a plurality of digital broadcasting receiving apparatuses for receiving a transport stream broadcast from the apparatus. hand,
The digital broadcast device stores a first storage unit storing the same first program that currently controls each digital broadcast receiving device, and stores a second program used in the digital broadcast receiving device. Second storage means, encrypting means for encrypting the second program using the first program as a key, and multiplexing and transmitting the encrypted second program to a transport stream. Each digital broadcast receiving apparatus includes a program storage unit storing the first program, and a separating unit separating the encrypted second program from the received transport stream. And decrypting means for decrypting the separated encrypted second program using the first program as a key.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a digital broadcasting system according to the present invention will be described below with reference to the drawings. (Embodiment 1) FIG. 1 is a configuration diagram of Embodiment 1 of a digital broadcasting system according to the present invention. The digital broadcasting system includes a digital broadcasting device 100 for transmitting a broadcasting signal.
Digital broadcast receiving apparatus 11 for receiving broadcast signals
0.

The digital broadcasting apparatus 100 includes a content server 101 and a program DB (database) 102.
, A new program DB 103, an encryption control unit 104,
It includes an encryption processing unit 105, a multiplexing unit 106, and a modulation unit 107. Each digital broadcast receiving device 110 includes a demodulation unit 111, a TS decoder 112, a video processing unit 113
, An audio processing unit 114, an encryption / decryption unit 115, a non-volatile memory 116, a RAM 117, and a CPU 118.

The content server 101 stores one or more contents, and stores the contents in MPEG (Mov).
ing Picture Experts Grou
p) Notify the multiplexing unit 106 in the form of a transport stream packet of the 2 standard. Here, the content is a program broadcast on each channel and includes video data and audio data. Further, the content server 101
The multiplexing unit 106 is notified of program sequence information (PSI: Program Specific Information), which is information necessary for program selection in the digital broadcast receiving apparatus 110 that receives the transport stream.

The program DB 102 manages a control program currently operating in each digital broadcast receiving apparatus 110. Note that the control program operating in each digital broadcast receiving apparatus 110 may be different depending on the maker or model of the digital broadcast receiving apparatus, and even if the same model of the same maker uses a different version. is there. Therefore, a plurality of types of control programs are usually managed in the program DB 102.

Each control program includes a main data of the control program and a unique I / O identifying the maker name and model of the digital broadcast receiving apparatus 110 to which the control program is applied.
D and the version number of the control program. The new program DB 103 manages an upgraded control program (hereinafter, referred to as a “new control program”) used as a new control program in place of the control program currently operating in each digital broadcast receiving apparatus 110. The new control program is transmitted from the digital broadcasting device 100 to each digital broadcast receiving device 110 for a predetermined period, and after being replaced with the current control program by the compatible digital broadcast receiving device 110,
The data is transferred to the program DB 102 by the encryption control unit 104.

The new control program, like the running program, has a data body of the control program and a unique ID.
And a version number. The encryption control unit 104 stores customer management information and encryption conditions, and controls the encryption processing unit 105. The customer management information describes a user ID for each user who receives a digital broadcast, a unique ID of the digital broadcast receiving device 110, and an encryption method of the digital broadcast device 110.

The encryption condition describes a plurality of encryption methods, and defines an encryption method corresponding to a unique ID of, for example, each maker or model of the digital broadcasting device 110 to be used. Upon receiving an instruction to send a new control program from an instruction unit (not shown), the encryption control unit 104 reads the new control program stored in the new program DB 103. The encryption method corresponding to the unique ID of the read new control program is selected from the encryption conditions, and is notified to the encryption processing unit 105.

Further, the encryption control unit 104 matches the unique ID of the new control program according to the selected encryption method,
The control program having the version number immediately before the version number of the new control program is read out from the program DB 102, and the encryption processing unit 10
Notify 5 The encryption processing unit 105 includes the encryption control unit 104
Encrypts the data body of the new control program in accordance with the encryption method notified by.

The encryption processing unit 105 includes a new control program and a control program currently operating in the digital broadcast receiving apparatus 110 corresponding to the new control program (hereinafter referred to as “operating control program”). Has been notified. FIG. 2 is a schematic diagram illustrating a state of the encryption processing in the encryption processing unit 105.
The encryption processing unit 105 encrypts (scrambles) the data body 203 of the new control program using a part of the data body 201 of the operating control program as an encryption key 202 according to the encryption method, and encrypts the new control program. Generate the converted data body 204.

Here, the encryption key 202 is the data body 20
1 is used, and the encryption processing is performed by calculating the exclusive OR of the data body 203 of the new control program and the encryption key 202, for example, by a predetermined encryption method. New program data body 20
4 is generated. As shown in FIG. 3, the encryption processing unit 105 stores the data body 2 of the generated encrypted new program.
04, download data 305 to which a version number 301, a unique ID 302, a current version number 303, and an encryption attribute 304 are added as header information.
Notify 6. Here, the version number 301 is a version number of the new control program, and the unique ID 302 is an identifier indicating a maker name or a model name of the specific digital broadcast receiving apparatus 110 common to the new control program and the operating control program. The current version number 303 is the version number of the operating control program, and the encryption attribute 30
Reference numeral 4 denotes an address which is position information of the data body 201 of the operating control program which is the encryption key 202.

The multiplexing unit 106 includes the content server 101
Together with the program information and the transport stream packet of the content notified from
Is multiplexed into the transport stream and notified to the modulator 107.
Modulating section 107 modulates the transport stream notified from multiplexing section 106 into a broadcast signal and transmits the broadcast signal to each digital broadcast receiving apparatus 110.

Next, the digital broadcast receiving apparatus 110 will be described. The demodulation unit 111 receives and demodulates a broadcast signal transmitted from the digital broadcasting device 100 under the control of the CPU 118, and notifies the TS decoder 112 of a transport stream. The TS decoder 112 is a CPU
According to the control of No. 18, video packets are separated from the notified transport stream and notified to the video output unit 113, audio packets are separated and notified to the audio output unit 114,
The program arrangement information packet is separated and written into the RAM 117, and the packet of the download data 305 is separated and RA
M117 is written, and the CPU 118 is also notified.

The video output unit 113 includes a TS decoder 112
Is converted into a signal that can be displayed on an external monitor and output. The audio output unit 114
The audio packet notified from the decoder 112 is converted into an analog audio signal and output to an external speaker. Upon receiving the notification of the decryption key from the CPU 118, the encryption / decryption unit 115 reads out the data body of the encrypted new control program stored in the RAM 117 using the decryption method stored in advance, and uses the decryption key. Decrypt (descramble). For example, if the decryption method is the calculation of exclusive OR, the exclusive OR of the encrypted new control program and the decryption key is calculated and decrypted. The decrypted new control program is written into the RAM 117.

FIG. 4 is a schematic diagram for explaining a decryption process in the encryption / decryption unit 115. The data body 204 of the encrypted new control program is stored in RAM by the CPU 118.
117 is written. The data body 201 of the operating control program is stored in the nonvolatile memory 116. The encryption / decryption unit 115 is notified from the CPU 118 as part of the data of the data body 201 of the operating control program as the decryption key 401. Encryption / decryption unit 115
Is decrypted by the decryption method storing the data body of the new control program encrypted using the decryption key 401 notified, and the data body 2 of the decrypted new control program is decrypted.
03 is written into the RAM 117, and the end of decryption is
Notify 18.

The decryption key 401 is the same as the data used as the encryption key 202 in the encryption processing unit 105 in the digital broadcasting device 100. Non-volatile memory 11
Reference numeral 6 includes a flash ROM or the like, and stores a control program for controlling each unit of the digital broadcast receiving apparatus 110. The CPU 118 controls each unit according to the control program. The non-volatile memory 116 stores the data body 201 of the currently operating control program together with the version number. The data body 203 of the upgraded new control program is written into the RAM 117, and after the CPU 118 confirms that the new control program is correct, the new control program is stored in the nonvolatile memory 116 in place of the operating control program.

The RAM 117 is configured as a work area of the CPU 118, in which the program arrangement information separated by the TS decoder 112 is written, and the download data 305 separated by the TS decoder 112 is written.
Further, the RAM 117 stores the data body 2 of the encrypted new control program contained in the download data 305.
04 decrypted new control program data body 20
3 is written by the decryption unit 115.

The CPU 118 controls each unit according to the operating control program stored in the nonvolatile memory 116. The CPU 118 separates one or more download data 305 by the TS decoder 112,
When written into the RAM 117, the unique ID of the header information
302 determines whether there is download data that matches the unique ID of the own device 110, and if it determines that there is no download data,
Download data 30 that is more suitable for decoder 112
Instruct 5 to separate. If they match, it is determined whether or not the version number 301 is an updated version number of the operating control program stored in the nonvolatile memory 116. If not, T
Download data 3 more suitable for S decoder 112
05, and deletes the download data 305 in the RAM 117. When affirmative, RAM 117
Attribute 30 of download data 305 recorded in
4 is read. According to the address described in the encryption attribute 304, a part of the data of the operating control program stored in the non-volatile memory 116 is obtained as a decryption key, and is notified to the decryption unit 115.

When the CPU 118 receives a notification from the encryption / decryption unit 115 that the new control program has been decrypted,
It is determined whether the data body of the new control program stored in the RAM 117 is normal, and if it is normal, the new control program is transcribed in place of the operating control program currently stored in the nonvolatile memory 116. . Thereafter, the digital broadcast receiving apparatus 110 is controlled by the upgraded new control program.

Next, the operation of the digital broadcast receiving apparatus 110 for decrypting the encrypted new control program will be described with reference to the flowchart of FIG. First, the TS decoder 1
In step 12, the download data 305 is separated from the transport stream and written to the RAM 117. CPU1
18 determines whether the unique ID 302 of the header information of the download data 305 matches the unique ID of the own device, and if not, waits for separation of the download data 305 of the matching unique ID (S502).

Next, the CPU 118 determines whether or not the version number 301 of the header information is an updated version number of the version number stored in the nonvolatile memory 116 (S504). Return to CP
If U118 is affirmative, the download data 305
(S506), read the encryption attribute 304 of the header information, and read the encryption attribute 3 from which the partial data of the operating control program stored in the nonvolatile memory 116 is read.
04, it is obtained as a decryption key 401. The obtained decryption key 401 is notified to the decryption unit 115 (S50).
8).

The decryption unit 115 receives the decryption key 4
01, the encrypted data body 204 of the new control program stored in the RAM 117 is decrypted, and the decrypted data body 203 of the new control program is generated. CPU 118 is the data body 2 of the new control program.
03 is normal or not, and if normal, the RAM 11
7 is transferred to the nonvolatile memory 116 and replaced with the operating control program (S
510).

As a result, the version of the control program is updated. Thereafter, it is controlled by this new control program. As described above, by decrypting (encrypting) a part of the data of the currently operating control program as a decryption key (encryption key), the key information is separately transmitted from the digital broadcasting apparatus 100 to the digital broadcasting receiving apparatus 110. At the same time, there is no need to transmit highly confidential data.

In this embodiment, the encryption key 202
Although the (decryption key 401) uses a part of the data body 201 of the operating control program, the whole data may be used, or a part of discontinuous parts may be collectively used as described later. . Further, although the unique ID 302 is included in the header information, the unique ID 302 may be included in the data body of the new control program to be encrypted.

A CATV in which the digital broadcasting apparatus 100 and the digital broadcasting receiving apparatus 110 are connected by a cable.
, Etc., the version number 30 is added to the header information.
1, the encrypted data body of the new control program may be transmitted to all the digital broadcast receiving apparatuses 110 without including the unique ID 302 and the current version number 303.

Further, as for the encryption method, an example of exclusive OR was shown, but other algorithms can be used. Further, the download data 305 may be transmitted by another medium such as a public line, or when the digital broadcasting apparatus 100 is a CATV or the like that relays a broadcast from a satellite or the like, OoB (Out-Of-BAND). ) Can be transmitted in a different frequency band from video and audio.

In the above embodiment, the decryption method of the new control program encrypted by the digital broadcast receiving apparatus 110 is stored in the decryption section 115 in advance. The decryption method may be described in the encryption attribute 304 and transmitted. (Modification) In this modification, the encryption key is a set of discontinuous partial data of the operating control program. In this modification, a plurality of digital broadcast receiving devices 11
0, it is assumed that a different version of the control program is used for the operating control program.

As shown in FIG. 6, in each digital broadcast receiving apparatus 110, a version 1 control program 601 and a version 2 control program 602 are operating. The position information “10”, “8”,
Each data "F", represented by "100", "256",
“E”, “0”, and “1” are encryption keys 603. Position information “150”, “65”, “6” of the control program 602
Each data "F", "E", "0",
“1” is similarly set as the encryption key 603.

The encryption processing unit 105 performs an encryption process on the version 3 control program 604 using the encryption key 603, and obtains the version 3 encrypted control program 60.
5 is generated. FIG. 7 shows the download data 700 generated by the encryption processing unit 105. The download data contains the encrypted version 3 control program 605 and its header information as version number 70.
1, a unique ID 702, and an encryption attribute 703.

The encryption attribute 703 includes position information 704 and 705 of the operating control programs 601 and 602 indicating the encryption key 603. The download data 700 is multiplexed into a transport stream from the digital broadcasting device 100, and the digital broadcast receiving device 1
Sent to 10. When the version 1 control program 601 is stored in the non-volatile memory 116, the encryption / decryption unit 115 of the digital broadcast receiving apparatus uses the version 1 position information 704 of the encryption attribute 703 as a decryption key.
Is used. Similarly, when the version 2 control program 602 is stored in the non-volatile memory 116, the version information 704 of the encryption attribute 703 is used as the decryption key.

(Embodiment 2) FIG. 8 is a block diagram of a digital broadcast receiving apparatus according to Embodiment 2 of the present invention. The digital broadcast receiving apparatus includes a demodulation unit 111, a TS decoder 112, a video output unit 113, and an audio output unit 114
, A decryption unit 115, a non-volatile memory 116,
AM 117, CPU 802, external device control unit 803
The external device control unit 803 is connected to the external device 804. The same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted. The configuration unique to the present embodiment will be described.

In the present embodiment, the transport stream received by the digital broadcast receiving apparatus 801 is multiplexed with the encrypted control program used by the external device connected to the digital broadcast receiving apparatus 801 as download data. Have been. The unique ID of the external device 804 is described in the header information of the download data instead of the version number 301 (see FIG. 3).

Even when the unique ID of the external device 804 connected to the external device control unit 803 is described in the header information of the download data, the CPU 802 sends the encryption key to the encryption / decryption unit 115 similarly to the above embodiment. The control program is notified and decrypts the encrypted control program to generate a decrypted control program. The CPU 802 reads the generated control program from the RAM 117 and notifies the external device control unit 803.

The external device control unit 803 is, for example, an IEEE
External device 804 via an interface such as 1394
It is connected to the. The external device control unit 803 includes the CPU 8
02 is output to the external device 804. The external device 804 receives the control program output from the external device control unit 803 and updates its own control program. Note that this external device 804 is
For example, it is a game device, and develops a game according to an input control program. If the external device 804 is a stereo device, a karaoke device that operates according to the input control program is realized.

It should be noted that the external device control unit 803 uses the IEEE
Although it is assumed that the external device 804 is connected to the external device 804 by 1394, other connection methods may be used.
In the present embodiment, the decrypted control program is output to the external device 804. However, the decrypted control program may be output in an encrypted state and decrypted by the external device 804. In this case, the external device 804 is added to the encryption attribute.
Describes that an encryption key using a part of data of the control program currently operating is used, and the entire download data is output to the external device 804.

The control program may be decrypted by the digital broadcast receiving apparatus 801, encrypted by another encryption method, and output to the external device 804. Further, in each of the above embodiments, the configuration is shown in FIGS. 1 and 8, but a program for causing a computer to perform the functions of each component is recorded on a computer-readable recording medium, and such an operation is performed. Apply to a digital broadcasting system without the function of encrypting (decrypting) the new control program with the encryption key (decryption key) using the medium control program,
The same effect as the present invention can be exerted.

[0045]

As described above, according to the present invention, the first storage means for storing the same first program that currently controls each digital broadcast receiving apparatus, and the digital broadcast receiving apparatus Second storage means for storing a second program to be used, encryption means for encrypting the second program using the first program as a key,
A transmitting unit that multiplexes the encrypted second program into a transport stream and broadcasts the multiplexed program. With such a configuration, when transmitting the encrypted second program, it is not necessary to transmit the encryption key at the same time, and the second program with enhanced confidentiality is transmitted for each digital broadcast receiving apparatus. Can be.

Further, the encrypting means includes an encrypted second
This program has a header information adding unit for adding header information that records, as an encryption attribute, which part of the first program data is used as an encryption key. With such a configuration, encryption can be performed using partial data of the first program stored in the transmission destination digital broadcast receiving apparatus, so that confidentiality can be improved.

Further, the first program has a plurality of versions, and the header information adding section records an encryption attribute for each version. With such a configuration, even when each digital broadcast receiving apparatus is controlled by a different version of the first program, the encrypted second program can be decrypted by each digital broadcast receiving apparatus. it can.

The present invention also relates to a digital broadcast receiving apparatus for receiving a transport stream obtained by multiplexing a second program encrypted using a first program as a key, and storing the first program. Storage means, a separating means for separating the encrypted second program from the received transport stream, and a decryption of the separated encrypted second program using the first program as a key. And decoding means for performing the decoding. With such a configuration, the second program transmitted with increased confidentiality can be easily decrypted.

Also, the encrypted second program is added with header information which records which part of the first program data was used as an encryption key as an encryption attribute, and the decryption means A decryption key obtaining unit that reads out data of a portion recorded in the encryption attribute from the first program data stored in the storage unit and obtains a decryption key; and a second program encrypted with the obtained decryption key. And a decoding processing unit for decoding. With such a configuration, the encrypted second program can be easily decrypted using the data stored in the digital broadcast receiving device itself.

Further, the header information further includes a unique ID for identifying the digital broadcast receiving apparatus, and the separating means includes a unique ID included in the added header information.
D is to separate the encrypted second program that matches that of its own device. With such a configuration, the second program suitable for the digital broadcast receiving apparatus can be acquired in a highly confidential state.

The first program is a control program currently in operation, and the second program is
The control program is an upgraded version, and it is determined whether or not the program decrypted by the decryption means is normal. When the program is determined to be normal, the decrypted program is stored in the storage means. Replacement means for replacing the first program. With this configuration, the encrypted second program can be decrypted and replaced with the currently operating control program.

Further, the digital broadcast receiving apparatus according to the fourth, fifth or sixth aspect further comprises an external device control means connected to an external device, wherein the external device control means is configured to decode the second device decoded by the decoding means. Is output to the external device when the program is normal, and the external device is controlled by the output second program. With such a configuration, the second program for controlling the external device connected to the digital broadcast receiving device can be acquired in a highly confidential state.

Further, the present invention is a digital broadcasting system comprising a digital broadcasting device and a plurality of digital broadcasting receiving devices for receiving a transport stream broadcast from the device, wherein the digital broadcasting device A first storage unit that stores the same first program that currently controls the broadcast receiving device, and a second storage unit that stores a second program used in the digital broadcast receiving device. An encryption unit that encrypts the second program using the first program as a key, and a transmission unit that multiplexes the encrypted second program into a transport stream and broadcasts the encrypted second program. Each of the digital broadcast receiving apparatuses includes a program storage unit that stores the first program, and a cipher based on the received transport stream. Separating means for separating the second program that has been, and the second program encrypted separated by a further comprising a decoding means for decoding using the first program as a key. With such a configuration, it is possible to obtain a digital broadcast system that can easily transmit and receive highly confidential programs without simultaneously transmitting an encryption key from the digital broadcast device to the digital broadcast receiving device.

The present invention also provides a transport stream storing a first program and multiplexing a second program controlled by the first program and encrypted using the first program as a key. A computer-readable recording medium applied to a receiving digital broadcast receiving apparatus, comprising: a separating unit configured to separate an encrypted second program from a received transport stream;
A computer-readable recording medium that stores a program that causes a computer to perform the functions of a decryption unit that decrypts the separated encrypted second program using the first program as a key, and a decryption unit. With such a configuration, the recording medium is applied to a digital broadcast receiving apparatus that does not have a function of decrypting the encrypted second program using the first program that controls the own apparatus, and this function is provided. Can be demonstrated.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a digital broadcast system according to a first embodiment of the present invention.

FIG. 2 is a schematic diagram illustrating encryption processing of a new control program in an encryption processing unit according to the embodiment.

FIG. 3 is a diagram illustrating a structure of download data generated by an encryption processing unit according to the embodiment.

FIG. 4 is a schematic diagram illustrating a decryption process in the encryption / decryption unit of the embodiment.

FIG. 5 is a flowchart illustrating a decoding operation of a new control program in the digital broadcast receiving device of the embodiment.

FIG. 6 is a schematic diagram illustrating an encryption process according to a modification of the embodiment.

FIG. 7 is a diagram illustrating a structure of download data generated by an encryption processing unit according to the modification.

FIG. 8 is a configuration diagram of a digital broadcast receiving apparatus according to a second embodiment of the present invention.

FIG. 9 is a configuration diagram of a conventional broadcast receiving apparatus.

[Explanation of symbols]

 REFERENCE SIGNS LIST 100 digital broadcasting device 101 content server 102 program DB 103 new program DB 104 encryption control unit 105 encryption processing unit 106 multiplexing unit 107 modulation unit 110,801 digital broadcast receiving device 111 demodulation unit 112 TS decoder 113 video output unit 114 audio output unit 115 Encryption / decryption unit 116 Non-volatile memory 117 RAM 118,802 CPU 803 External device control unit 804 External device

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Teruhide Kita 1006 Kazuma Kadoma, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd. 72) Inventor Tsuneo tvno 1006 Kazuma Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. F term (reference) 5C025 AA30 BA25 BA27 DA01 5C064 CA14 CB01 CC04

Claims (10)

[Claims] 1. A first storage means for storing the same first program that currently controls each digital broadcast receiving apparatus, and a second program for storing a second program used in the digital broadcast receiving apparatus. Second storage means, encryption means for encrypting the second program using the first program as a key, and multiplexing and transmitting the encrypted second program to a transport stream. A digital broadcast device comprising: a transmission unit. 2. A header information adding unit for adding, to a second encrypted program, header information that records, as an encryption attribute, which part of the first program data is used as an encryption key. The digital broadcast device according to claim 1, comprising: 3. The digital broadcast device according to claim 2, wherein the first program has a plurality of versions, and the header information adding unit records an encryption attribute for each version. 4. A digital broadcast receiving apparatus for receiving a transport stream obtained by multiplexing a second program encrypted using a first program as a key, wherein the storage stores the first program. Means for separating the encrypted second program from the received transport stream; and decryption means for decrypting the separated encrypted second program using the first program as a key. A digital broadcast receiving device comprising: 5. The encrypted second program includes:
Header information that records which part of the first program data is used as the encryption key as an encryption attribute is added, and the decryption unit converts the first program data stored in the storage unit into an encryption attribute. 5. The apparatus according to claim 4, further comprising: a decryption key acquisition unit that reads out data of the recorded portion to acquire a decryption key; and a decryption processing unit that decrypts a second program encrypted with the acquired decryption key. Digital broadcast receiver. 6. The header information further includes a unique ID for identifying the digital broadcast receiving device, wherein the separating unit matches the unique ID included in the added header information with that of the own device. The digital broadcast receiving device according to claim 5, wherein the encrypted second program is separated. 7. The first program is a control program that is currently operating, the second program is a version upgrade of the control program, and the program decrypted by the decryption means is normal. 6. A method according to claim 4, further comprising the step of replacing the decrypted program with the first program stored in said storage means when determining whether or not there is a normal program. Or the digital broadcast receiving device according to 6. 8. The digital broadcast receiving apparatus according to claim 4, further comprising an external device control unit connected to an external device, wherein the external device control unit decodes the second device decoded by the decoding unit. The digital broadcast receiving device outputs the program to the external device when the program is normal, and the external device is controlled by the output second program. 9. A digital broadcasting system comprising a digital broadcasting device and a plurality of digital broadcasting receiving devices for receiving a transport stream broadcast from the device, wherein each of the digital broadcasting devices includes: A first storage unit that stores the same first program that is currently being controlled; a second storage unit that stores a second program used in the digital broadcast receiving apparatus; An encryption unit for encrypting the second program using the first program as a key; and a transmission unit for multiplexing the encrypted second program into a transport stream for broadcasting. The apparatus comprises: program storage means for storing the first program; and a second program encrypted from the received transport stream. Digital broadcasting system, characterized in that it comprises a separating means for separating the program, a second program encrypted separated decoding means for decoding using the first program as a key. 10. A digital broadcast storing a first program and receiving a transport stream multiplexed with a second program controlled by the first program and encrypted using the first program as a key. A computer-readable recording medium applied to a receiving device, comprising: a separating unit that separates an encrypted second program from a received transport stream; A computer-readable recording medium in which a program for causing a computer to perform the functions of a decryption unit and a decryption unit using the first program as a key is recorded.