JP2001285820A - Storage playback charging system and storage playback charging method - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide a system capable of performing storage / playback accounting without being affected by updating of a work key Kw, while maintaining compatibility with stream accounting. SOLUTION: In a storage / playback charging system for storing and playing back broadcasted video, audio or data on a receiving side and charging at the time of storage or playback, a broadcast facility side 1 stores a video, audio or data in a scramble key. A scrambling processing means 11 for encrypting the scramble key with a work key and an ECM sending means 12 for sending the encrypted scramble key with a work key. After the decryption, it has an encryption conversion means 33 for re-encrypting with a fixed key, and the receiving side has an accumulating means 22 for accumulating the encrypted video, audio or data, and the re-encrypted scramble key. I do. The stored program can be reliably reproduced without being affected by the update of the work key Kw every fixed period. Also,
It has compatibility with the stream billing method.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a charging system in a storage type broadcasting system for storing, reproducing, and viewing broadcast programs, and a charging method thereof. It is configured to have.

[0002]

2. Description of the Related Art Hitherto, conditional access broadcasting that allows viewing only when a viewing contract is made has been put to practical use. In this conditional access system, the transmitting side encrypts the video and audio of the program with a scramble key (Ks) that is updated every few seconds, encrypts this Ks with a work key (Kw), and obtains the scrambled video and audio. And the encrypted K
and s broadcast.

[0003] The receiving side holds Kw if it has the viewing qualification of this program, decodes Ks using this Kw, and decrypts and presents the video and audio scrambles using the decoded Ks.

FIG. 10 shows a conventional digital broadcasting system that performs conditional access. This system comprises a station equipment 1 on the broadcasting side, a receiver 2 for receiving a broadcast, and a security module 3 such as an IC card arranged in the receiver 2. The station equipment 1 converts the video and audio data of the program into K
s, and an ECM (Entitlement Control Message) including this Ks.
e: common information) is encrypted with Kw and transmitted. Security module 3
A Kw accumulator 32 for holding Kw and a real-time ECM decoder 31 for decoding ECM with Kw and extracting Ks are provided. Further, the receiver 2 includes a descrambling processing unit 21 for descrambling the scrambled video and audio with Ks obtained from the security module 3.

In this system, the station equipment 1 sends a video and audio of a program encrypted by Ks and an E / E encrypted by Kw.
CMs are multiplexed and broadcast.

[0006] The receiver 2 that has received the broadcast sends the received scrambled data to the descramble processing unit 21 and sends the ECM to the security module 3.

When a viewing contract is made, Kw is transmitted to the security module 3 from the station equipment 1 in an encrypted form, and the security module 3
This Kw is decrypted with a master key (Km) unique to the security module 3 and stored in the Kw storage unit 32.
Real-time ECM input by encrypted ECM
The decoding unit 31 decodes the ECM using Kw stored in the Kw storage unit 32, sequentially extracts Ks updated in a short cycle, and outputs the Ks to the descramble processing unit 21 of the receiver 2. The descrambling processing unit 21 of the receiver 2 decodes the scrambled data with this Ks and outputs video and audio of the program. Such a charging method for real-time viewing is called a “stream charging method”.

[0008] In the digital broadcasting system, a storage type broadcasting system in which a broadcasted program is stored in a receiver or an external device, and a viewer reproduces and views the program at a desired time is being studied. In this storage-type broadcasting method, charging at the time of storing a program, charging at the time of reproducing a program, or a method of using them at the same time is being studied. Such a charging method for programs to be stored is called a “storage / playback charging method”. In the storage / playback accounting method, it is necessary to accumulate video / audio data of a program without losing security, whatever the charging time. Therefore, the video and audio data is stored in an encrypted state, and is decrypted at the time of reproduction.

Japanese Patent Application Laid-Open No. 11-234647 describes a storage / playback charging system in which a receiver receiving a broadcast stores program data scrambled by Ks and ECM encrypted by Kw. . In this system, during playback, the stored ECM is read out and
And Ks is extracted, and the video and audio of the program stored using this Ks are descrambled and presented. This system is configured such that billing for a program can be performed both at the time of accumulating the scrambled program data and at the time of reproducing the program data.

Further, in this system, it is possible to perform stream charging for real-time viewing and listening by using the respective units that execute storage and playback charging, and has compatibility with stream charging.

[0011]

However, this storage / playback charging system has the following problems.

That is, the work key Kw used for decrypting Ks
Is updated at a fixed cycle by the broadcasting station, so when playing back the stored program, the Kw held in the security module 3 may be different from that at the time when the program data was stored. At this time, the accumulated ECM cannot be decoded, and
Cannot be extracted, and the program data cannot be descrambled, and normal reproduction of the program becomes impossible.

The present invention solves such a problem, and provides a system capable of performing storage / playback accounting without being affected by the update of the work key Kw while maintaining compatibility with stream accounting. It is another object of the present invention to provide a storage / playback accounting method.

[0014]

SUMMARY OF THE INVENTION Accordingly, the present invention provides a storage / playback charging method for storing and playing back broadcasted video, audio or data on a receiving side and charging at the time of storage or playback. Has a security module that encrypts video, audio or data with a scramble key, encrypts the scramble key with a work key, sends out the encrypted video, audio or data and the encrypted scramble key, and has a security module. The receiver stores the encrypted video, audio, or data, decrypts the encrypted scramble key with the security module, re-encrypts it with a fixed key, and re-encrypts the re-encrypted scramble key. During playback, the security module decrypts the re-encrypted scramble key using a fixed key during playback, and decrypts it. Using the obtained scramble key, encrypted video, so that decoding the voice or data.

[0015] Further, the broadcast facility encrypts the video, audio or data with the scramble key, encrypts the scramble key with the work key, and transmits the encrypted video, audio or data and the encrypted scramble key. The receiver having the security module stores the encrypted video, audio or data, and generates a data string of the encrypted scramble key and work key with the security module, Is encrypted with a fixed key, the encrypted data string is stored on the receiving side, and at the time of reproduction, the security module decrypts the encrypted data string with the fixed key and uses the work key obtained by decryption. Decrypts the encrypted scramble key and decrypts the encrypted video, audio or data using the obtained scramble key. So that the reduction.

Further, the broadcasting equipment side encrypts the video, audio or data with the scramble key, encrypts the scramble key with the first work key, and further encrypts the scramble key with the second work key.
A second work key is encrypted with a first work key while a second work key is encrypted with a first work key, a scramble key encrypted with a first work key, and a second scramble key encrypted with a first work key.
The scramble key encrypted with the work key and the second work key encrypted with the first work key are sent out, and the receiving side having the security module transmits the encrypted video, audio or data and the second work key. In addition to accumulating the scrambled key encrypted by the security module,
The encrypted second work key is decrypted and held, and at the time of reproduction, the security module decrypts the scramble key encrypted with the second work key and uses the scramble key obtained by decryption to perform encryption. The decoded video, audio or data is decoded.

[0017] Further, in a storage / reproduction charging system for storing and reproducing broadcasted video, audio or data on the receiving side and charging at the time of storage or reproduction, the broadcasting equipment includes:
It has a scramble processing means for encrypting video, audio or data with a scramble key, and an ECM sending means for encrypting the scramble key with a work key and sending it out. After decrypting the decrypted scramble key,
The receiving side is configured to include encryption means for re-encrypting with a fixed key, and the receiving side is provided with storage means for storing the encrypted video, audio or data, and the re-encrypted scramble key. .

Further, the broadcasting equipment side includes a scramble processing means for encrypting video, audio or data with a scramble key, and an ECM transmission means for encrypting the scramble key with a work key and transmitting the same, and has a security module. On the receiving side, the security module generates a data string of the encrypted scramble key and the work key,
The receiving side includes an encryption unit that encrypts the data sequence with a fixed key, and the receiving side includes a storage unit that stores the encrypted video, audio, or data and the data sequence encrypted by the encryption unit. It is configured as follows. A storage / playback billing system, characterized in that:

Further, the broadcast equipment side has a scramble processing means for encrypting video, audio or data with a scramble key, and a first scramble key for encrypting the scramble key with a first work key.
An encryption means, a second encryption means for encrypting the scramble key with the second work key, and a third encryption means for encrypting the second work key with the first work key, and having a security module On the receiving side, the security module
The receiving side includes first decryption means for decrypting the encrypted second work key, and the receiving side stores the encrypted video, audio, or data and the scramble key encrypted with the second work key. It is configured to include a storage unit that performs the operation.

Therefore, the stored program can be reliably reproduced without being affected by the update of the work key Kw every fixed period. It also has compatibility with the stream charging method.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) In a storage / playback charging system according to a first embodiment, Ks is decrypted on the receiving side and then re-encrypted with a unique encryption key and stored.

As shown in FIG. 1, the system comprises a station equipment 1 on the broadcast side, a receiver 2 for receiving a broadcast, and a receiver 2 for receiving a broadcast.
And a security module 3 arranged at FIG. 1 shows only blocks related to the accumulation process. The station equipment 1 includes a scramble processing unit 11 for scrambling video and audio data of a program with a scramble key Ks.
And an ECM transmission unit 12 for encrypting the ECM including the Ks with the work key Kw and transmitting the encrypted ECM. The receiver 2 includes a storage unit 22 for storing the encrypted video and audio and the ECM.
The security module 3 further includes a Kw storage unit 32 that stores Kw, a storage encryption key storage unit 34 that stores a storage encryption key used for re-encryption of the ECM, and a storage device that decrypts the ECM. Cryptographic converter 33 that re-encrypts with an encryption key
And a billing information processing unit 35 that performs a billing process when storing a program. The stored encryption key is a key fixed to the security module 3, and for example, a master key Km can be used for the key.

In this system, video and audio of a program encrypted with Ks and E / V encrypted with Kw are transmitted from the station equipment 1.
CMs are multiplexed and broadcast.

The receiver 2 that has received the broadcast stores the scrambled video and audio data in the storage unit 22 as it is, and sends the encrypted ECM to the security module 3.

The cryptographic converter 33 of the security module 3
Decrypts the ECM using the Kw stored in the Kw storage unit 32, and then encrypts the decrypted ECM with the storage encryption key read from the storage encryption key storage unit. The encryption conversion unit 33 outputs the encrypted storage encryption ECM to the storage unit 22, and the storage encryption ECM is stored in the storage unit 22. Thus, the storage section 22 stores the scrambled video / audio data and the storage encryption ECM.

The cryptographic conversion unit 33 uses the identification information obtained from the ECM at the time of this cryptographic conversion
Send to 35. In response, the billing information processing unit 35 performs a billing process. The operation of this billing process is based on the conventional PPV (pay pe
r view) method, where viewing history information is stored in the security module and periodically uploaded to the center via a telephone line. The center executes a billing process based on the viewing history information.

FIG. 2 shows blocks related to the reproduction processing of this system. The receiver 2 includes a storage unit 22 for storing the scrambled video / audio data and the storage / encryption ECM, and a descramble processing unit 23 for decoding the video / audio data. In addition to the storage encryption key storage unit 34 and the billing information processing unit 35, a storage encryption ECM decryption unit 36 for decrypting the storage encryption ECM and extracting Ks is provided.

At the time of reproduction, the data stored in the storage unit 22 is
The scrambled video / audio data is output to the descramble processing unit 23, and the stored encrypted ECM is output to the stored encrypted ECM decryption unit 36 of the security module 3. The storage encryption ECM decryption unit 36 includes a storage encryption key storage unit.
The storage encryption key is read out from the storage 34, the storage encryption ECM is decrypted, Ks is extracted, and output to the descramble processing unit 23. The descrambling unit 23 uses this Ks to decode and output the scrambled video and audio data.

In this process, the storage / encryption ECM decryption unit 36 sends the identification information obtained from the ECM to the accounting information processing unit 35. In response to this, the billing information processing unit 35 performs a billing process at the time of reproduction.

As described above, in this system, the ECM encrypted with the storage encryption key is stored in the storage unit together with the scrambled video / audio data. for that reason,
Even when Kw is updated, decoding of video and audio data at the time of reproduction can be performed without any trouble.

The configuration of the station equipment is the same as that in the case of stream charging, and does not require any change. Also, in the receiver 2, it is possible to view the program in real time in the same procedure as in the case of the storage / playback billing, and to maintain compatibility with the stream billing.

Incidentally, a fixed key other than Km can be used as the stored encryption key. Although the case where data is stored in the storage unit inside the receiver is shown here, the data is stored in an external storage device, for example, an MD, DAT, memory card, DVD-RAM, HDD, or the like. Is also good.

(Second Embodiment) In a storage / playback charging system according to a second embodiment, a data string obtained by combining Kw and each ECM encrypted with Kw is encrypted with a storage encryption key and stored.

FIG. 3 shows blocks related to the storage processing of this system. The configurations of the station equipment 1 and the receiver 2 are the same as those of the first embodiment (FIG. 1). The security module 3 includes, in addition to the Kw storage unit 32, the storage encryption key storage unit 34, and the billing information processing unit 35, a storage encryption that encrypts a data string including the ECM and Kw encrypted with Kw with a storage encryption key. It has a conversion unit 37. A master key Km or the like can be used as the stored encryption key.

In this system, the station equipment 1 sends a video and audio of a program encrypted with Ks and an E / E encrypted with Kw.
The CM is multiplexed and broadcast, and the receiver 2 stores the scrambled video / audio data in the storage unit 22 and sends the encrypted ECM to the security module 3.

Storage encryption section of security module 3
37 stores the ECM, which is input through the receiver 2 and encrypted with Kw, and stores the KCM read out from the Kw storage unit 32 into the ECM.
w is connected to generate a data string, and this data string is encrypted with the stored encryption key read from the stored encryption key storage unit 34. FIG. 4 schematically shows the encrypted data string. This encrypted data string is stored in the storage encryption unit.
It is sent from 37 to the storage unit 22 and stored.

In this process, the storage encryption unit 37 sends the identification information obtained from the ECM to the accounting information processing unit 35. In response, the billing information processing unit 35 performs a billing process at the time of accumulation.

FIG. 5 shows blocks related to the reproduction processing of this system. The receiver 2 includes a storage unit 22 for storing the scrambled video / audio data and the stored encrypted data sequence, and a descramble processing unit 23 for decoding the video / audio data. Is provided with a stored encrypted data decryption unit 38 for decrypting the stored encrypted data sequence and extracting Ks, in addition to the stored encryption key storage unit 34 and the billing information processing unit 35.

At the time of reproduction, the scrambled video / audio data stored in the storage unit 22 is output to the descramble processing unit 23, and the stored encrypted data string is transmitted to the stored encrypted data decryption unit 38 of the security module 3. Is output. The storage encryption data decryption unit 38 is a storage encryption key storage unit.
34, the stored encryption key is read out, the stored encrypted data string is decrypted, and Kw
Decrypts the encrypted ECM, extracts Ks, and outputs it to the descramble processing unit 23. The descrambling unit 23 uses this Ks to decode and output the scrambled video and audio data.

At the time of this processing, the stored encrypted data decrypting section 38 sends the identification information obtained from the ECM to the billing information processing section 35. Perform billing processing.

The stored encrypted data string stored in the storage unit 22 is collectively stored in the security module 3 according to the processing capacity and storage capacity of the security module.
To the stored encrypted data decryption unit 38, or
The data is divided into blocks and transferred to the stored encrypted data decryption unit 38 of the security module 3 in synchronization with the descrambling timing. However, even when transferring the divided blocks, the receiver does not know the contents of the encrypted stored data, and therefore, transfers the data by dividing the designated blocks.

The stored encrypted data string may be stored in a storage device other than the security module.

As described above, in this system, the ECM and Kw encrypted with Kw are encrypted with the storage encryption key and stored in the storage unit. Therefore, even when Kw is updated, the ECM is decoded using the accumulated Kw,
Ks can be extracted, and decoding of video and audio data at the time of reproduction can be performed without any trouble. Further, since Kw is stored after being encrypted by the storage encryption key, security at the time of storage can be maintained.

Also, compatibility with stream charging can be achieved.

(Third Embodiment) In the storage / playback charging system of the third embodiment, the ECM encrypted with the work key KW for each program is transmitted from the station equipment, thereby reducing the processing load on the security module. ing.

FIG. 6 shows blocks related to the storage processing of this system. The station equipment 1 includes a scramble processing unit 11 for scrambling video / audio data of a program with a scramble key Ks, and a storage / playback ECM transmission unit for transmitting a storage ECM obtained by encrypting an ECM including the Ks with a program work key KW. And an ECM sending unit 12 for sending a stream charging ECM obtained by encrypting the ECM including Ks with the work key Kw and a Kw encrypted KW obtained by encrypting the program work key KW with the work key Kw. The device 2 includes a storage unit 22 for storing the encrypted video and audio and the storage ECM, and the security module 3
w, a Kw storage unit 32 for storing w, a storage encryption key storage unit 34 for storing a storage encryption key used for re-encryption of the KW, and a KW encryption KW, and then re-encryption with the storage encryption key. And a billing information processing unit 35 that performs billing processing when the program is stored. As the stored encryption key, for example, a master key Km can be used.

In this system, the scramble processing section 11 of the station equipment 1 encrypts the video and audio data of the program with the scramble key Ks to generate scramble data.
Further, the ECM sending section 13 for storing and charging for playback includes an ECM including Ks.
The CM is encrypted with the program work key KW to generate a stored ECM. KW is set for each program. Also, the accumulated ECM
Are stored on the receiving side and are used for storage and playback billing.

The ECM sending unit 12 encrypts the ECM containing Ks with the work key Kw, generates and sends a stream charging ECM. At the same time, KW is encrypted with Kw and transmitted. This ECM for stream charging is a conventional EC
The same as the ECM sent from the M sending unit,
It is not stored on the receiving side, and is used only for stream charging when the program is viewed in real time. Accordingly, stream charging is performed in the same manner as in the related art.

Thus, from the station equipment 1, the video and audio of the program encrypted with Ks, the stream charging ECM encrypted with Kw, the stored ECM encrypted with KW, and K
The KW encrypted with w is multiplexed and broadcast.

In the receiver 2 which has received the broadcast, the scrambled video / audio data and the storage ECM encrypted with the KW are stored in the storage unit 22, and the KW encrypted with the Kw is stored.
To the security module 3.

The cryptographic converter 33 of the security module 3
Decrypts the encrypted KW using the Kw stored in the Kw storage unit 32, and then decrypts the decrypted KW
The encryption is performed using the stored encryption key read from the stored encryption key storage unit 34. The encryption conversion unit 33 outputs the encrypted stored encryption KW
Is output to the storage unit 22, and the storage encryption KW is stored in the storage unit 22. Thus, the storage unit 22 stores the scrambled video / audio data, the storage ECM, and the storage encryption KW. The cryptographic conversion unit 33 also uses the identification information obtained from the KW at the time of this cryptographic conversion
The charge information processing section 35 performs the charge processing at the time of accumulation.

FIG. 7 is a flowchart showing the accumulation processing of this system.

Step 1: The scramble processing section 11 of the station equipment 1 scrambles the video / audio / data by Ks.

Step 11: The scrambled data is stored on the receiving side.

Step 2: E for storage / playback charging of station equipment 1
The CM sending unit 13 encrypts the stored ECM including Ks with KW and sends it.

Step 12: The stored ECM is stored on the receiving side.

Step 3: ECM sending section 12 of station equipment 1
Transmits KW after encrypting it with Kw.

Step 4: The security module on the receiving side performs a cryptographic conversion on the KW to generate a stored encrypted KW obtained by encrypting the KW with a stored encryption key. Step 13: The stored encrypted KW is received on the receiving side. accumulate.

FIG. 8 shows blocks related to the reproduction processing of this system. The receiver 2 receives the scrambled video / audio data, the stored ECM, and the stored encryption K
The security module 3 includes a storage unit 22 for storing W and a descrambling processing unit 23 for decoding video and audio data. The security module 3 includes a storage encryption key storage unit 34 and a billing information processing unit 35. A program work key decrypting unit 39 for decrypting KW from the stored encrypted KW, a program work key retaining unit 40 for retaining the decrypted KW, and a stored ECM for decrypting the stored ECM using KW and extracting Ks. And a decoding unit 41.

At the time of reproduction, the data stored in the storage unit 22 is
The scrambled video / audio data is output to the descramble processing unit 23, the stored encryption KW is output to the program work key decryption unit 39 of the security module 3, and the stored ECM is output to the stored ECM decryption unit 41. The program work key decryption unit 39 reads out the stored encryption key from the stored encryption key storage unit 34, decrypts the stored encrypted KW using this, and outputs the decrypted KW to the program work key holding unit 40. The program work key holding unit 40 holds the KW. Further, the program work key holding unit 40 sends the identification information included in the KW to the charging information processing unit 35, and the charging information processing unit 35 performs a charging process at the time of reproduction.

The stored ECM decrypting unit 41 reads out the KW from the program work key holding unit 40, decrypts the stored ECM,
And outputs it to the descramble processing unit 23. The descrambling unit 23 uses this Ks to decode and output the scrambled video and audio data.

FIG. 9 is a flowchart showing the reproduction processing of this system.

Step 21: Transfer the stored encrypted KW to the security module. Step 22: Extract the KW using the stored encryption key and hold it.

Step 23: Transfer the stored ECM to the security module in synchronization with scrambling. Step 24: Decode the stored ECM using KW,
s to the receiver.

Step 25: The descrambling processing section 23 of the receiver descrambles the scrambled data by Ks and outputs video / audio / data.

As described above, in this system, the station equipment 1
Generates a work key KW for each program, and uses this KW to encrypt Ks. On the other hand, on the receiving side, Ks encrypted with KW is stored, and KW encrypted with Kw is re-encrypted with a storage encryption key and stored. At this time, only one encryption conversion (encryption change) in the security module is required for one stored program.
The load on the security module is greatly reduced as compared with the cipher exchange for the CM (the cipher exchange for the ECM requires the exchange for all ECMs transmitted every few seconds).

Since the validity period of KW is shorter than Kw, KW has higher confidentiality than Kw. Therefore, safety is increased.

This system also has compatibility with stream charging.

Here, at the time of storage processing, the security module 3 re-encrypts the KW re-encrypted with the storage encryption key.
Is shown to be transferred to the storage unit 22 of the receiver 2, but the KW may be held in the security module 3 without being transferred to the storage unit 22. Holding in the security module 3 improves security.

If the validity period of the KW is shorter than the renewal period of the Kw, the confidentiality is high and the security is improved. Therefore, a sufficiently high effect can be obtained even if it is not set for each program, but is changed in units of one day, one week, or one month.

As described in the first embodiment,
It is also possible to use a fixed key other than Km as the stored encryption key. Further, instead of the storage unit inside the receiver, data is stored in an external storage device, for example, MD, DAT, a memory card,
It may be stored in a DVD-RAM, HDD, or the like.

[0072]

As is apparent from the above description, the storage / playback charging system of the present invention can reliably play back the stored program without being affected by the update of the work key Kw every fixed period.

Further, it is compatible with the stream charging method.

The accounting process can be performed both at the time of storing and reproducing a program.

[Brief description of the drawings]

FIG. 1 is a block diagram of a storage process in a storage / playback charging system according to a first embodiment of the present invention;

FIG. 2 is a block diagram of a playback process in the storage / playback accounting system according to the first embodiment;

FIG. 3 is a block diagram of a storage process in a storage / playback charging system according to a second embodiment of the present invention;

FIG. 4 shows an example of stored data in a storage / playback charging system according to a second embodiment;

FIG. 5 is a block configuration diagram of a playback process in a storage / playback charging system according to a second embodiment;

FIG. 6 is a block diagram of a storage process in a storage / playback charging system according to a third embodiment of the present invention;

FIG. 7 is a flowchart showing a procedure of a storage process in a storage / playback charging system according to a third embodiment;

FIG. 8 is a block diagram of a playback process in a storage / playback accounting system according to a third embodiment;

FIG. 9 is a flowchart showing a procedure of a playback process in the storage / playback charging system according to the third embodiment;

FIG. 10 is a block diagram showing a configuration of a conventional stream charging system.

[Explanation of symbols]

 Reference Signs List 1 station equipment 2 receiver 3 security module 11 scramble processing unit 12 ECM transmission unit 13 ECM transmission unit for storage / playback accounting 21 descrambling processing unit 22 storage unit 23 descrambling processing unit 31 real-time ECM decoding unit 32 Kw storage unit 33 encryption conversion Unit 34 Stored encryption key storage unit 35 Accounting information processing unit 36 Stored encryption ECM decryption unit 37 Stored encryption unit 38 Stored encrypted data decryption unit 39 Program work key decryption unit 40 Program work key holding unit 41 Stored ECM decryption unit

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H04N 7/167 H04L 9/00 601E H04N 5/92 H 7/167 Z (72) Inventor Hironori Murakami Osaka Prefecture 1006 Kadoma Kadoma Matsushita Electric Industrial Co., Ltd.F-term (reference) LL09

Claims (14)

[Claims] 1. A storage / playback charging method for storing and playing back broadcasted video, audio or data on a receiving side and charging at the time of storage or playback. In addition, the scramble key is encrypted with a work key, and the encrypted video, audio or data and the encrypted scramble key are sent out. After storing the video, audio or data, the security module decrypts the encrypted scramble key, then re-encrypts it with a fixed key, and stores the re-encrypted scramble key on the receiving side. During playback, the security module decrypts the re-encrypted scramble key using the fixed key, A storage / playback billing method, wherein the encrypted video, audio or data is decrypted using a scramble key obtained by decryption. 2. A storage / playback charging method for storing and playing back broadcasted video, audio or data on a receiving side and charging at the time of storage or playback. In addition, the scramble key is encrypted with a work key, and the encrypted video, audio or data and the encrypted scramble key are sent out. While storing the video, audio or data, the security module generates a data string of the encrypted scramble key and work key, encrypts the data string with a fixed key, and encrypts the data string. The data sequence is stored on the receiving side, and at the time of reproduction, the security module uses the fixed key to encrypt the data sequence. And decrypting the encrypted scramble key using the work key obtained by the decryption, and using the obtained scramble key,
A storage / playback billing method, wherein the encrypted video, audio or data is decrypted. 3. A storage and playback charging method for storing and playing back broadcasted video, audio or data on a receiving side and charging at the time of storage or playback, wherein the broadcasting equipment uses a scramble key to store the video, audio or data. , The scramble key is encrypted with a first work key, the scramble key is further encrypted with a second work key, and the second work key is encrypted with the first work key and encrypted. The video, audio or data, the scramble key encrypted with the first work key, the scramble key encrypted with the second work key, and the second work key encrypted with the first work key The receiving side having a security module transmits the encrypted video, audio or data and the scramble encrypted with the second work key. With accumulate the door,
In the security module, the encrypted second
The work key is decrypted and stored, and at the time of reproduction, the second
Decrypting the scramble key encrypted with the work key,
A storage / playback billing method, wherein the encrypted video, audio or data is decrypted using a scramble key obtained by decryption. 4. The security module according to claim 3, wherein the decrypted second work key is re-encrypted with a fixed key in the security module, and the re-encrypted second work key is stored on the receiving side. The storage / playback charging method described in the above. 5. The method of claim 3, wherein a validity period of the second work key is shorter than a renewal period of the first work key. 6. The method according to claim 5, wherein the second work key is set for each program. 7. The storage / playback charging method according to claim 1, wherein a master key is used as the fixed key. 8. A storage / playback charging system for storing and playing back broadcasted video, audio or data on the receiving side and charging at the time of storage or playback, wherein the broadcasting facility uses a scramble key to store the video, audio or data. And scrambling processing means for encrypting the scramble key with a work key, and ECM sending means for sending the encrypted scramble key with a work key. After decryption, it comprises an encryption conversion means for re-encrypting with a fixed key, and the receiving side comprises a storage means for storing the encrypted video, audio or data, and the re-encrypted scramble key. A storage / playback billing system characterized by: 9. The security module includes a decryption unit for decrypting the re-encrypted scramble key using the fixed key, and a receiving side includes a scramble key decrypted by the decryption unit. 10. A descramble processing means for decoding the video, audio, or data encrypted by using a descrambling method.
3. The storage / playback charging system according to (1). 10. A storage / playback charging system for storing and playing back broadcasted video, audio or data on the receiving side and charging at the time of storage or playback, wherein the broadcasting facility uses a scramble key to store the video, audio or data. And scrambling processing means for encrypting the scramble key with a work key, and sending the encrypted scramble key with a work key. An encryption means for generating a data string with a work key and encrypting the data string with a fixed key, wherein the receiving side encrypts the encrypted video, audio or data with the encryption means; And a storage means for storing the converted data string. 11. The security module decrypts the encrypted data sequence using the fixed key, and uses the work key obtained by the decryption to encrypt the scrambled data included in the data sequence. A decryption means for decrypting a key; and a descrambling processing means for decrypting the encrypted video, audio or data using the scramble key decrypted by the decryption means on the receiving side. The storage / playback charging system according to claim 10, further comprising: 12. A storage / playback charging system for storing and playing back broadcasted video, audio or data on the receiving side and charging at the time of storage or playback. Scramble processing means for encrypting with the first work key, first scramble processing means for encrypting the scramble key with the first work key,
A receiving side having a security module, comprising: second encrypting means for encrypting the scramble key with a second work key; and third encrypting means for encrypting the second work key with the first work key. The security module comprises first decryption means for decrypting the encrypted second work key, the receiving side comprising: the encrypted video, audio or data, and the second work key And a storage means for storing the scramble key encrypted in (1). 13. The security module further includes second decryption means for decrypting the scramble key encrypted with the second work key, and a receiving side decrypts the scramble key by the second decryption means. 13. The storage / playback charging system according to claim 12, further comprising a descrambling processing unit for decoding the encrypted video, audio or data using the scramble key. 14. The first decryption means of the security module re-encrypts the decrypted second work key with a fixed key, and the storage means stores the re-encrypted second work key. 13. The storage / playback charging system according to claim 12, wherein: