JP2001251290A - Data broadcasting system and content distribution, storage and playback methods - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide a data broadcasting system which distributes data broadcasting contents so as not to be illegally acquired. SOLUTION: A broadcasting equipment side 1 is provided with a content encryption means 12 for encrypting content with a charging key and a charging key encryption means 15 for encrypting a charging key, and a receiver 2 is provided with a charging key. Data broadcast protocol interpreting means 21 for extracting the encrypted content is provided. The security module 3 of the receiver is provided with transfer encryption means 35 for encrypting the decrypted accounting key with the transfer key. To transfer the content encrypted with the charging key and the charging key encrypted with the transfer key, and to the external device, a transfer key generating means 41,
A billing key decrypting unit for decrypting the billing key encrypted with the transfer key and a content decrypting unit 43 for decrypting the encrypted content with the billing key are provided. Since the raw content is not taken out by the receiver, high security can be maintained and illegal acquisition of the content can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data broadcasting system for distributing charged contents, a method of distributing contents, and a method of storing and reproducing contents, and more particularly to preventing unauthorized acquisition of contents by a third party. is there.

[0002]

2. Description of the Related Art At present, data broadcasting is broadcast in cases where it is not necessary to consider copyright protection of contents very much. In the future, a service for downloading music data, game data, etc. through data broadcasting will be started. Then, in order to protect the copyright of these contents, copyright protection of the contents is required, and therefore, a process of distributing the contents in consideration of the copyright of the contents is required.

[0003] In order to charge data broadcasting contents, a system shown in FIG. 6 has been proposed.

[0004] This system is a broadcasting facility 1 for encrypting contents with a charging key (scramble key) and broadcasting the data.
A receiver 2 for receiving a data broadcast, a security module 3 such as an IC card arranged in the receiver 2,
MD or DA where data broadcast content is stored
And an external device (storage device) 4 such as a memory card, a memory card, a DVD-RAM, and an HDD.

[0005] The broadcasting equipment 1 includes a content generation unit 11 for generating content, a charging key generation unit 14 for generating a charging key (scramble key) for each content, and a content encryption unit 12 for encrypting the content with a charging key. And a content sending unit 13 for sending encrypted content, and an ECM creating unit 15 for creating and sending ECM (Entitlement Control Messages: common information) storing a charging key.

[0006] On the other hand, in the storage device for storing the contents, (1) the contents for which charging processing has been completed (including the case where the viewing contract has been established) are decrypted (the contents can be immediately reproduced). Storage device that stores data in the state (mainly MD
Storage device (HD) for storing together (2) scrambled content before charging is completed and information for charging.
D, etc.).

In the former case, the receiver 2 operates as shown in FIG.
A data broadcast protocol interpreting unit 21 for interpreting a data broadcast protocol and extracting encrypted content;
It comprises a charging decryption unit 22 for decrypting the content using the charging key decrypted by the card 3 and a content transfer unit 23 for transferring the decrypted content to the external device (storage device) 4.

[0008] The IC card 3 interprets the ECM broadcast from the broadcasting equipment 1 to extract a charging key, and an ECM interpreting unit 31 for extracting the extracted charging key and a charging decoding unit 22 of the receiver 2.
And a charging key transfer unit 32 for transferring the information to the charging key.

In this system, the content encrypted with the charging key (scramble key) is broadcasted from the broadcasting equipment 1 through the content transmitting section 13 and the charging key is transmitted by the conventional standard conditional access method. Like EC
M, and the ECM is encrypted with the work key Kw and broadcast simultaneously with the content.

[0010] In the receiver 2 receiving this data broadcast,
The encrypted content is sent to the accounting decryption unit 22, and the received ECM is transmitted to the ECM interpretation unit 31 of the IC card 3.
Sent to The ECM interpreting unit 31 decrypts the ECM by using the work key Kw obtained through the broadcast in advance when the user has the viewing qualification for the content according to the viewing contract,
Take out the charging key. The extracted billing key is transferred to the billing decryption unit 22 of the receiver 2, and the billing decryption unit 22 decrypts the encrypted content using the billing key. The decrypted content is transferred to the external device 4 and stored.

[0011]

However, this data broadcasting system has the following problems. (1) Since unencrypted raw data is generated in the receiver due to decryption of the content, analyzing the software in the receiver may make it easier to illegally retrieve the raw content. Yes, if the extracted content is copied and distributed, the copyright of the content is infringed. Therefore, this system does not provide sufficient protection against the copyright of the content. (2) When the decrypted content is transmitted from the receiver to an external device through a network, the content needs to be re-encrypted by the receiver. However, when an encryptor is installed in the receiver, the encryption itself is performed. Will be less secure.

That is, in many cases, it is assumed that various processing means are formed into chips in an external device and data is stored in a recording medium, so that it is difficult to extract raw content data from the external device. However, at the receiver,
Since the processing in the receiver is performed mainly by software, the software can be analyzed and data can be obtained. Therefore, the receiver is easily targeted for unauthorized access. Also,
There are many manufacturers who develop and manufacture receivers, and the specifications of the receivers are released to ensure that the broadcasting standards are properly observed.

[0013] In the case of storing scrambled contents before charging is completed, there is the following problem. (3) At present, the scramble key (charging key) is transmitted from the broadcast facility 1 after being encrypted with the work key Kw, and the work key is updated at a constant cycle. Therefore, if the scrambled content is stored in the storage device as it is, when the content is reproduced, the work key held by the security module 3 is different from that at the time when the content was stored. In this case, normal reproduction cannot be performed.

The present invention solves such a problem. In the process of distributing, accumulating, and reproducing data broadcast contents, a malicious third person does not hinder reproduction and viewing of a well-intentioned viewer.
Provides a data broadcasting system that can prevent unauthorized acquisition of content by users, and distributes, stores,
It aims to provide a method of reproduction.

[0015]

SUMMARY OF THE INVENTION Therefore, according to the present invention, in a data broadcasting system for distributing charged contents, a data broadcasting content is encrypted with a charging key, and the charging key is encrypted and encrypted. Broadcasting equipment for transmitting contents and an encrypted charging key, a receiver having a security module for receiving data broadcasting, and an external device to which data broadcasting contents received by the receiver are transferred from the receiver. The receiver transmits the received encrypted content as it is to the external device, and the security module decrypts the received encrypted charging key, encrypts it with the encryption key, and sends it to the external device. The external device holds the encryption key, decrypts the encrypted accounting key, and uses the accounting key to encrypt the encrypted content. It is configured to decode the tool.

[0016] Further, the content of the data broadcast is encrypted with a billing key, the billing key is encrypted, and the broadcasting equipment for transmitting the encrypted content and the encrypted billing key is provided. Providing a receiver for receiving the broadcast, and an external device having storage means for storing the content of the data broadcast received by the receiver,
The receiver transfers the received encrypted content to the external device as it is, and the security module decrypts the received encrypted charging key, encrypts it with the encryption key, and transfers it to the external device. The external device is configured to store the encrypted content and the billing key encrypted with the encryption key in the storage unit.

[0017] In addition, the content of the data broadcast is encrypted with a billing key, the billing key is encrypted, and the broadcasting equipment for transmitting the encrypted content and the encrypted billing key is provided. A receiver for receiving the broadcast and storing it in a built-in storage means, the security module decrypts the received encrypted charging key, and then encrypts it with the encryption key. The encrypted content and the accounting key encrypted with the encryption key are stored in the storage unit.

[0018] In the data broadcasting content distribution method for distributing the charged content, the broadcasting equipment side includes:
The content of the data broadcast is encrypted with the charging key, the charging key is encrypted, the encrypted content and the encrypted charging key are transmitted, and the receiver receives the content encrypted with the charging key. Take out from the data, the security module of the receiver decrypts the encrypted charging key included in the received data, then encrypts it with the encryption key,
The content encrypted with the charging key and the charging key encrypted with the encryption key are transferred from the receiver to the external device, and the external device decrypts the charging key using the encryption key and converts the charging key. It is configured to decrypt the content that has been encrypted using the content.

[0019] In the content storing method of data broadcasting for distributing the charged content, the broadcasting equipment side includes:
The content of the data broadcast is encrypted with the charging key, the charging key is encrypted, the encrypted content and the encrypted charging key are transmitted, and the receiver receives the content encrypted with the charging key. Take out from the data, the security module of the receiver decrypts the encrypted charging key included in the received data, then encrypts it with the fixed key,
The content encrypted with the charging key and the charging key encrypted with the fixed key are stored in the storage unit of the receiver or the external device.

Further, in the method of storing and reproducing data broadcasting contents for distributing the charged contents, the broadcasting equipment encrypts the data broadcasting contents with a charging key, and encrypts and encrypts the charging key. The receiver transmits the content and the encrypted charging key, the receiver extracts the content encrypted with the charging key from the received data, and the security module of the receiver decrypts the encrypted charging key included in the received data. After that, the content encrypted with the fixed key and the content encrypted with the charging key and the charging key encrypted with the fixed key are stored in the storage unit of the receiver or the external device.At the time of reproduction, the security module stores the content in the storage unit. The stored billing key encrypted with the fixed key is decrypted, and the receiver or an external device reads the cipher read from the storage means using the billing key. It is configured to play by decoding the content being.

Therefore, since live content does not appear in the receiver, distribution, accumulation,
During reproduction, high security can be maintained, and illegal acquisition of contents by a third party can be prevented.

In addition, the contents before charging is completed are
Since the data is stored in an encrypted state, security can be ensured, and billing can be performed at the time of reproduction.

In addition, since the content can be distributed by a conventional method of encrypting the content with a charging key (scramble key) and transmitting the scramble key with a work key, the conventional receiver can view and listen as usual. It can be carried out.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) As shown in FIG. 1, a data broadcasting system according to a first embodiment includes a broadcasting facility 1, a receiver 2, an IC card 3, and an external device 4. , The broadcasting equipment 1 is, similarly to FIG.
1, a charging key generation unit 14, a content encryption unit 12, a content transmission unit 13, and an ECM creation unit 15.

The receiver 2 includes a data broadcast protocol interpreting section 21 for interpreting a data broadcast protocol and extracting encrypted content, and an encrypted content transfer section for transferring the encrypted content to the external device 4 as it is. twenty four
Is provided.

The IC card 3 includes an ECM interpreting unit 31 for decoding the ECM broadcasted from the broadcasting equipment 1, an ECM obtaining unit 33 for extracting a charging key (scramble key) from the decoded ECM, a charging key A transfer key generation unit 34 for generating a transfer key for encrypting the transfer key, a transfer encryption unit 35 for encrypting the charging key using the transfer key, and an encryption for transferring the encrypted charging key to the external device 4. And a charging key transfer unit 36.

The external device 4 has a transfer key generation unit 41 for generating a transfer key similar to the transfer key generation unit 34 of the IC card 3.
An encryption accounting key decryption unit 42 for decrypting the accounting key encrypted using the transfer key, and a content decrypting unit 43 for decrypting the content encrypted using the decrypted accounting key. And a content acquisition unit 44 for acquiring the decrypted content.

In this system, as in the case of the system (FIG. 6) shown in the conventional example, the contents encrypted with the charging key (scramble key) and the charging key are stored from the broadcasting equipment 1 and the work is performed. The ECM encrypted with the key Kw is simultaneously broadcast.

In the receiver 2 receiving this data broadcast,
The data broadcast protocol interpreter 21 interprets the data broadcast protocol, extracts the encrypted content from the received data, and the encrypted content transfer unit 24 transfers the encrypted content to the external device 4 as it is. I do.

The received ECM is an IC card 3
Is transmitted to the ECM interpreting unit 31, and the ECM interpreting unit 31 decrypts the ECM using the work key Kw acquired in advance through the broadcast when the user has the authority to view the content. ECM
The acquisition unit 33 extracts the charging key from the decrypted ECM and outputs the charging key to the transfer encryption unit 35.

The transfer key generation unit 34 generates the same transfer key as that generated by the external device 4 and outputs the same to the transfer encryption unit 35. The operation of generating the same transfer key in cooperation with the external device 4 will be described later.

The transfer encryption unit 35 encrypts the accounting key using the transfer key generated by the transfer key generation unit 34. The charging key encrypted with the transfer key is transferred to the external device 4 through the encryption charging key transfer unit 36.

The encrypted billing key transferred from the receiver 2 is input to an encrypted billing key decryption unit 42 of the external device 4,
The encrypted content is input to the content decrypting unit 43 of the external device 4.

The encryption / charging key decryption unit 42 includes a transfer key generation unit 41
The content decrypting unit 43 decrypts the encrypted charging key using the transfer key generated in the above, and decrypts the encrypted content using the charging key, and outputs the decrypted content to the content obtaining unit 44. Output to

As described above, the IC card 3 and the external device 4 generate the same transfer key and perform encryption and decryption of the accounting key. FIG. 2 shows the operation of the IC card 3 and the external device 4 at this time.

Step 1: The IC card 3 acquires the charging key. Step 2 (Step 11): The IC card 3 and the external device 4
The mutual authentication is performed by exchanging the IDs with each other, and the other party is confirmed. If the mutual authentication succeeds, Step 12: The external device 4 transfers the data that is the source of the transfer key generation to the IC card. For example, the data of the time measured by the external device 4 is used as the original data of the transfer key generation as I data.
Give it to C card.

Step 3: The IC card 3 is connected to the external device 4
Step 4: Using the original data, a transfer key is generated in accordance with the transfer key generation algorithm.

Step 13: The external device 4 also has the same algorithm for generating the transfer key. By using the same original data, the external device 4 transfers the same transfer key as the transfer key generated by the IC card 3 to the external device 4. But it can be generated.

Step 5: The IC card 3 encrypts the billing key with the transfer key and transfers this encrypted billing key to the external device 4. Step 14: The external device 4 decrypts the encrypted billing key with the transfer key. Step 15: Receive the charging key.

As described above, each time the IC card 3 and the external device 4 transfer the encrypted charging key, the IC card 3 and the external device 4 regenerate the transfer key again, and transfer the charging key encrypted with the transfer key to the IC card 3. To the external device 4.

In this system, even when the charging process is completed and the decrypted content is provided to the external device, the receiver 2 does not take out the raw content, so that high security can be maintained. it can. Also, from the receiver 2 to the external device 4 through the network,
Even when the received content is transmitted, the received encrypted content and the billing key encrypted by the IC card 3 may be transmitted, and the receiver 2 itself does not need to perform the encryption.

Since the receiver 2 does not require encryption or decryption, even a normal receiver that handles only data broadcasting without a charging function has a mechanism for connecting an IC card to an external device. Just by making the contents broadcast, it can be used for a data broadcasting system for charging contents.

(Second Embodiment) In the system of the second embodiment, the charging key is encrypted using a fixed key.

In this system, as shown in FIG.
The C card 3 includes, in addition to the ECM interpretation unit 31 and the ECM acquisition unit 33, a fixed key storage unit 37 for holding a fixed key and a decrypted E
A cryptographic converter 38 for encrypting the CM using a fixed key, and a fixed key encryption E for transferring the encrypted ECM to the external device 4
And a CM transfer unit 39.

The external device 4 includes a content decrypting unit 43
In addition to the content acquisition unit 44, a fixed key storage unit 45 that holds the same fixed key as the fixed key stored in the fixed key storage unit 37 of the IC card 3, and an ECM that is encrypted using this fixed key. Key encryption EC that decrypts and acquires the billing key
M decoding section 46 is provided. Broadcasting equipment 1 and receiver 2
Is the same as that of the first embodiment (FIG. 1).

This system is substantially different from the system of the first embodiment only in that when the accounting key is encrypted and transferred from the IC card 3 to the external device 4, it is encrypted using a fixed key. Are different.

As the fixed key, a master key individually given to the IC card 3 can be used. If the information on the master key is transferred only once from the IC card 3 to the external device 4, there is no need to exchange information on the key thereafter.

However, this one-time master key information exchange must be performed safely. Therefore, according to the procedure shown in FIG. 2 of the first embodiment, the IC card 3 and the external device 4
Generates a transfer key, and the IC card 3 encrypts the master key with the transfer key and transfers it to the external device 4. The external device 4 decrypts the master key with the transfer key and receives the master key.

In this way, the external device 4 can be
, The information of the fixed key can be transmitted safely.

(Third Embodiment) In the third embodiment,
A system will be described in which scrambled content and information for charging are stored in an external device, and the content is reproduced by the external device.

In this system, as shown in FIG.
The C card 3 includes an ECM interpreting unit 31 for decoding the ECM broadcasted from the broadcasting facility 1, an ECM obtaining unit 33 for extracting a charging key (scramble key) from the decoded ECM, and a master key for holding a master key. A storage unit 61; an encryption conversion unit 38 for encrypting the decrypted charging key with the master key; a master key encryption charging key transfer unit 62 for transferring the charging key encrypted with the master key to the external device 4. And a master key encryption / decryption unit 63 for decrypting information encrypted with the master key.

The external device 4 decrypts the content encrypted by the charging key and the charging key encrypted by the master key by the storage unit 48 and the master key encryption / decryption unit 63 of the IC card 3. Decryption charging key holding unit for storing the obtained charging key
47, a content decrypting unit 43 for decrypting the encrypted content using the decrypted accounting key, and a content acquiring unit 44 for acquiring the decrypted content. The configurations of the broadcasting equipment 1 and the receiver 2 are the same as those of the first embodiment (FIG. 1).

In this system, the broadcast equipment 1 stores the content encrypted with the charging key (scramble key) and the charging key, and stores the content in the ECM encrypted with the work key Kw.
And are broadcast simultaneously.

In the receiver 2 receiving this data broadcast,
The data broadcast protocol interpreter 21 interprets the data broadcast protocol, extracts the encrypted content from the received data, and the encrypted content transfer unit 24 transfers the encrypted content to the external device 4 as it is. I do. The transferred encrypted content is stored in the storage unit 48 of the external device 4.

The received ECM is an IC card 3
Is transmitted to the ECM interpreting unit 31, and the ECM interpreting unit 31 decrypts the ECM using the work key Kw acquired through broadcasting in advance. The ECM acquisition unit 33 extracts the accounting key from the decrypted ECM and outputs the accounting key to the encryption conversion unit 38. The encryption conversion unit 38 encrypts the accounting key using the master key stored in the master key storage unit 61. The accounting key encrypted with the master key is transferred to the external device 4 through the master key encryption accounting key transfer unit 62, and is stored in the storage unit 48 of the external device 4.

On the other hand, at the time of data reproduction, the accounting key stored in the storage unit 48 of the external device 4 and encrypted with the master key is transferred to the master key encryption / decryption unit 63 of the IC card 3. The master key encryption / decryption unit 63 decrypts the encrypted charging key using the master key stored in the master key storage unit 61, and stores the decrypted charging key storage unit 47 of the external device 4.
Transfer to At this time, the IC card 3 performs a billing process.

The decryption / charging key holding unit 47 of the external device 4
Holding the billing key transferred from the card 3, the content decryption unit 43 of the external device 4 reads the encrypted content read from the storage unit 48 with the billing key stored in the decryption billing key storage unit 47. Decrypted using the content acquisition unit 44
Obtains the decrypted content.

In this way, the content that has been encrypted and stored is reproduced.

As described above, in this system, the content is stored in an encrypted state on the receiving side.
The charging key sent by the ECM from the transmitting side is once decrypted, re-encrypted with the master key, and stored.
Therefore, at the time of reproduction, the encrypted charging key can be decrypted with the master key, and the encrypted content can be decrypted and reproduced using the decrypted charging key.

Therefore, regardless of whether the work key is updated, it is possible to reproduce the encrypted content.

(Fourth Embodiment) In the fourth embodiment,
A system will be described in which scrambled content and information for charging are stored in an external device, and the content is reproduced by a receiver.

In this system, as shown in FIG. 5, the external device 4 includes a storage unit 48, and the receiver 2 includes a data broadcast protocol interpretation unit 21 and an encrypted content transfer unit.
24, a decryption charging key storage unit 25 for storing the charging key decrypted by the master key encryption / decryption unit 63 of the IC card 3, and the encrypted contents transferred from the storage unit 48 of the external device 4. A content decrypting unit 26 that decrypts the content by using the decrypted accounting key, and a content acquiring unit 27 that acquires the decrypted content. The configurations of the broadcast facility 1 and the IC card 3 are the same as those of the third embodiment (FIG. 4).

In this system, the contents encrypted with the charging key and the charging key encrypted with the master key are stored in the storage unit 48 of the external device 4 in the same procedure as in the third embodiment. You.

At the time of data reproduction, the storage unit of the external device 4
The charging key encrypted with the master key stored in 48 is transferred to the master key encryption / decryption unit 63 of the IC card 3, and the master key encryption / decryption unit 63 converts the encrypted charging key into the master key. The decryption is performed using the master key stored in the storage unit 61, and the decrypted charge key is transferred to the decryption accounting key storage unit 25 of the receiver 2. At this time, the IC card 3 performs a billing process.

The content decryption unit 26 of the receiver 2 decrypts the encrypted content transferred from the storage unit 48 of the external device 4 using the accounting key stored in the decryption accounting key storage unit 25. , The content acquisition unit 27 acquires the decrypted content.

In this manner, the content encrypted and stored in the storage section 48 of the external device 4 can be reproduced by the receiver 2.

In the third and fourth embodiments, the case where the encrypted content is stored in the external device has been described. However, a storage unit is provided in the receiver, and the encrypted content is encrypted with the charging key here. It is possible to accumulate the contents and the billing key encrypted with the master key. Also, by having the configuration of the third and fourth embodiments as an external device or a receiver as a reproducing means, it is possible to receive the content. The content stored in the device can be reproduced by an external device or a receiver.

The systems of the third and fourth embodiments can be applied to a billing system based on a paper view.

[0069]

As is clear from the above description, in the data broadcasting system of the present invention, high security can be maintained, and illegal acquisition of contents from the receiver can be prevented.

Further, the encrypted content before the charging is completed can be stored as it is while maintaining security, and it becomes possible to charge the content at the time of reproduction.

At the time of this reproduction, even if the work key has already been updated, the content can be reproduced without any trouble.

Further, a normal receiver that handles only data broadcasting without a charging function can be diverted to a system that charges contents by a slight change in configuration.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a data broadcasting system according to a first embodiment of the present invention;

FIG. 2 is a flowchart showing a transfer key transfer processing procedure in the data broadcast system of the first embodiment;

FIG. 3 is a block diagram showing a configuration of a data broadcasting system according to a second embodiment of the present invention;

FIG. 4 is a block diagram showing a configuration of a data broadcasting system according to a third embodiment of the present invention;

FIG. 5 is a block diagram showing a configuration of a data broadcasting system according to a fourth embodiment of the present invention;

FIG. 6 is a block diagram of a conventional data broadcasting system.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Broadcasting equipment 2 Receiver 3 IC card 4 External device 11 Content generation unit 12 Content encryption unit 13 Content transmission unit 14 Charging key generation unit 15 ECM creation unit 21 Data broadcasting protocol interpretation unit 22 Charging decryption unit 23 Content transfer unit 24 Encryption Encrypted content transfer unit 25 Decryption charge key holding unit 26, 43 Content decryption unit 27, 44 Content acquisition unit 31 ECM interpretation unit 32 Charge key transfer unit 33 ECM acquisition unit 34 Transfer key generation unit 35 Transfer encryption unit 36 Encrypted charge key transfer Units 37, 45 Fixed key storage unit 38 Encryption conversion unit 39 Fixed key encryption ECM transfer unit 41 Transfer key generation unit 42 Encryption charge key decryption unit 46 Fixed key encryption ECM decryption unit 47 Decryption charge key storage unit 48 Storage unit 61 Master key storage unit 62 Master key encryption charging key transfer unit 63 Master key encryption / decryption unit

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H04N 7/08 G06F 15/21 Z 7/081 330 7/16 340B H04N 7/08 Z F term (reference) 5B049 AA05 BB11 CC05 CC08 CC36 DD04 DD05 EE03 EE23 EE28 FF08 FF09 GG04 GG07 GG10 5C025 BA25 BA30 DA01 DA05 5C063 AB05 AC10 CA40 5C064 BA01 BB02 BC06 BC20 BC22 BC27 BD16 DA01 DA10 5J104 AA01A02A

Claims (22)

[Claims] In a data broadcasting system for distributing charged content, a data broadcasting content is encrypted with a charging key and the charging key is encrypted, and the encrypted content and the encrypted charging key are transmitted. A broadcasting facility for transmitting, a receiver having a security module and receiving a data broadcast, and an external device to which the content of the data broadcast received by the receiver is transferred from the receiver, the receiver comprising: The security module transfers the encrypted content as it is to the external device, and the security module decrypts the received encrypted charging key, encrypts it with the encryption key, and transfers it to the external device. , The external device holds the encryption key, decrypts the encrypted charging key, and uses the charging key to perform encryption. Data broadcasting system characterized by decoding the content that. 2. The data broadcasting system according to claim 1, wherein the security module and the external device each include an encryption key generation unit that generates the same encryption key. 3. The security module and the external device according to claim 2, wherein the encryption key generation means of the external device shares original data and generates the same encryption key based on the original data. Data broadcasting system. 4. The encryption key generation unit of the external device sends the original data to the encryption key generation unit of the security module, and the security module and the encryption key generation unit of the external device output the original data based on the original data. The data broadcasting system according to claim 2, wherein the same encryption key is generated. 5. The cryptographic key generation means of the security module and the external device updates the cryptographic key each time a charging key encrypted with the cryptographic key is transferred from the security module to the external device. The data broadcasting system according to claim 2, wherein 6. The data broadcast system according to claim 1, wherein the security module and the external device each hold the same fixed key as the encryption key. 7. The data broadcasting system according to claim 6, wherein the fixed key is a master key assigned to the security module. 8. The security module and the external device each include an encryption key generation unit that generates an identical encryption key based on shared original data, wherein the security module replaces the fixed key with the encryption key. Encrypted using the encryption key generated by the generation unit and transferred to the external device, and the external device decrypts the encrypted fixed key using the encryption key generated by the encryption key generation unit. The data broadcasting system according to claim 6, wherein the data broadcasting system holds the data. 9. In a data broadcasting system for distributing charged content, a data broadcasting content is encrypted with a charging key and the charging key is encrypted, and the encrypted content and the encrypted charging key are transmitted. A broadcast facility for transmitting, a receiver having a security module and receiving a data broadcast, and an external device having a storage unit for storing the content of the data broadcast received by the receiver, wherein the receiver receives Transfer the encrypted content as it is to the external device, the security module decrypts the received encrypted charging key, encrypts it with an encryption key, and transfers it to the external device, The external device stores the encrypted content and a billing key encrypted with the encryption key in the storage unit. Data broadcasting system according to claim Rukoto. 10. In a data broadcasting system for distributing charged content, a data broadcasting content is encrypted with a charging key and the charging key is encrypted, and the encrypted content and the encrypted charging key are transmitted. A broadcasting facility for transmitting, and a receiver having a security module, receiving the data broadcast and storing the data broadcast in a built-in storage means, wherein the security module decrypts the received encrypted charging key. A data broadcast system, wherein the receiver encrypts the received content and the charging key encrypted with the encryption key in the storage unit. 11. The data broadcasting system according to claim 9, wherein the encryption key is a master key assigned to the security module. 12. The security module includes an encryption key encryption / decryption unit that decrypts an encrypted accounting key stored in the storage unit, and the external device or the receiver includes the encryption key encryption / decryption unit. The data according to any one of claims 9 to 11, wherein the encrypted content read from the storage means is decrypted and reproduced using the charging key decrypted by the decryption means. Broadcast system. 13. The data broadcasting system according to claim 12, wherein the security module performs the accounting process at the same time as the accounting key is decrypted by the encryption key encryption / decryption unit. 14. A data broadcasting content distribution method for distributing charged content, wherein the broadcasting equipment encrypts the data broadcasting content with a charging key, encrypts the charging key, and The receiver sends out the encrypted accounting key, the receiver extracts the content encrypted with the accounting key from the received data, and the security module of the receiver extracts the encrypted accounting key included in the received data. After the decryption, the content is encrypted with the encryption key, and the receiver encrypts the content encrypted with the charging key and the charging key encrypted with the encryption key from the receiver to the external device. And decrypting the encrypted content using the charging key. 15. The content distribution method according to claim 14, wherein the security module and the external device generate the encryption key from common original data. 16. The security module and the external device update the encryption key each time a charging key encrypted with the encryption key is transferred from the security module to the external device. Content distribution method described in. 17. The content distribution method according to claim 14, wherein the security module and the external device hold the same fixed key as the encryption key. 18. The security module and the external device generate an encryption key from common original data, and the security module encrypts the fixed key with the encryption key and transfers the encrypted key to the external device. 18. The content distribution method according to claim 17, wherein decrypting the fixed key by using the encryption key and storing the fixed key. 19. The content distribution method according to claim 17, wherein a master key assigned to the security module is used as the fixed key. 20. A data broadcast content storage method for distributing a charged content, wherein the broadcast facility encrypts the data broadcast content with a charging key, encrypts the charging key, and stores the encrypted content and the encrypted content. The receiver sends out the encrypted accounting key, the receiver extracts the content encrypted with the accounting key from the received data, and the security module of the receiver extracts the encrypted accounting key included in the received data. A content storage method comprising: after decrypting, encrypting with a fixed key, and storing the content encrypted with the charging key and the charging key encrypted with the fixed key in storage means of a receiver or an external device. . 21. A method for storing and reproducing data broadcasting contents for distributing charged contents, wherein the broadcasting equipment encrypts the data broadcasting contents with a charging key, and encrypts the charging key. The receiver sends out the content and the encrypted charging key, the receiver extracts the content encrypted with the charging key from the received data, and the security module of the receiver transmits the encrypted charging included in the received data. After decrypting the key, the content is encrypted with the fixed key, and the content encrypted with the charging key and the charging key encrypted with the fixed key are stored in a storage unit of a receiver or an external device. The module decrypts the charging key stored in the storage unit and encrypted with the fixed key, and uses the charging key with a receiver or an external device. And
A content storage / reproduction method, wherein the encrypted content read from the storage means is decrypted and reproduced. 22. When the security module decrypts the charging key encrypted with the fixed key,
22. The content storage / reproduction method according to claim 21, wherein a charging process is performed.