JPH11213553A - Contract managing device and reproducing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make literary works audio-visual within the period of a contract by controlling the reproducing operation of a reproducing device with a signal transmitted to control the receiving operation of broadcasting waves based on an audio-visual contract. SOLUTION: When a DVD-ROM is inserted into a DVD reproducing device and a reproduction is instructed, the device retrieves license information whose ID is matched with ciphered content information from a license storage part. When the license information corresponding to the ID of the content information exist, the efficiency of the license information is checked, and when the license information are not effective because the effective period of the information is expired or the like, the DVD reproducing device does not perform the decoding and the reproducing of the content information. On the other hand, when the information are effective, the device performs the decoding and the reproducing of the content information. Thus, a charge (a charge being an amount equivalent to a literary property) with respect to the viewing of the content information of a customer is replaced with the reception contract fee of a satellite broadcast in this manner.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention distributes content information encrypted on a recording medium such as a DVD to a customer (for a fee), and transmits control information including decryption key information of the content information by satellite broadcasting, for example. The present invention relates to an information distribution system that distributes content information to a playback device and enables viewing according to a viewing contract (for example, a viewing period) of the content information.

[0002]

2. Description of the Related Art In recent years, digital information processing technology and communication technology such as broadband ISDN have been developed, and advanced information recording media, such as DVDs, for realizing large capacity, high image quality, and high sound quality have been developed. With the diversification and sophistication of such information transmission means, digitalized works and the like are distributed in large quantities to users via networks, recording media, etc., and users can freely distribute them. A usable environment is being created. Such an environment increases the chances of unauthorized duplication, unauthorized modification, and unintended distribution of the copyrighted work, and does not unduly harm the owner of the copyrighted work. That raises concerns.

[0003] In order to dispel the concerns of the copyright holder of such a work, a work which can quickly and easily distribute a digitized work and provide a digital information use environment in which such a work can be used properly. The development of a system that assumes the protection of rights will be an important issue in the future.

[0004] DVD is a large-capacity personal computer medium replacing CD-ROM, and can be expected to spread to various uses such as movies, music, games, and karaoke. It is expected that DVD title prices will be kept low and the rental DVD market will expand. Accordingly, from such a viewpoint, information based on the idea of protecting copyright of information based on the idea of charging for use rather than possession of a digitized work recorded on a recording medium such as a DVD. Distribution system is indispensable.

On the other hand, digital broadcasting is a communication satellite (C
Starting from S), as the digitalization of cable TV and terrestrial broadcasting progresses, further enhancement of services is expected, and it is expected that broadcasting services will play a leading role in the future.

[0006] The greatest feature of digital broadcasting is that the introduction of information compression technology has improved the use efficiency of the frequency required for transmitting a program, and has enabled a significant increase in the number of broadcast channels as compared to analog broadcasting. That is. Further, since advanced error correction technology is applied, it is possible to provide high quality and uniform services.

[0007] Digitization of broadcasting has made it possible to provide multimedia services in various information formats (video, audio, text, data, etc.), and systems for providing such services have appeared one after another.

In such a system, when providing a pay broadcast service for descrambling or decoding based on the contents of a contract, customer management must be performed in accordance with the contract period. The customer management according to the contract period is, for example, to enable viewing of the program of the contract channel only within the contract period contracted by paying a predetermined fee.

[0009] Also, key information for scrambling or deciphering at the receiving device is provided to only legitimate viewers (according to the contract channel and the contract period) and reliably in order to prevent unauthorized viewing. There is a need.

[0010]

SUMMARY OF THE INVENTION Accordingly, the present invention is based on the premise that a digitized work is distributed quickly and easily, and that copyright protection is based on a contract for viewing the digitized work. It is an object of the present invention to provide an information distribution system that provides an environment for using digital information.

[0011] The present invention is a contract management apparatus for controlling a reproduction apparatus for reproducing encrypted content information recorded on a recording medium by broadcasting based on a viewing contract.
A playback device that plays back content information recorded on a recording medium such as a VD can be controlled by broadcasting based on a viewing contract.
It is an object of the present invention to provide a contract management device that enables viewing of digitized work (content information) recorded on a recording medium such as D for a contract period only.

[0012] Further, the present invention makes it possible to reproduce encrypted content information recorded on a recording medium such as a DVD only during a viewing contract period of the content information based on control information broadcasted. It is an object of the present invention to provide a playback device that can be used.

[0013]

SUMMARY OF THE INVENTION A contract management apparatus according to the present invention is a contract management apparatus for controlling a reproduction apparatus for reproducing encrypted content information recorded on a recording medium by broadcasting based on a viewing contract. Decoding encrypted control information including first key information for decrypting at least the encrypted content information associated with each piece of content information, and decrypting the encrypted control information; Means for broadcasting distribution of key generation information necessary for generating the second key information, and a signal distributed for controlling a broadcast wave receiving operation based on a viewing contract, and By controlling the playback operation, a playback device that plays back content information recorded on a recording medium such as a DVD can be controlled by broadcasting based on a viewing contract. Can allow viewing Le of be permissible viewing of (content information) only to the contract period.

[0014] The contract management apparatus of the present invention is a contract management apparatus for controlling a reproduction apparatus for reproducing encrypted content information recorded on a recording medium by broadcasting based on a viewing contract. Encrypted control information including at least first key information for decrypting the encrypted content information associated with each of the pieces of content information and identification information of the playback device; and the encrypted control information. Means for broadcasting distribution of key generation information necessary for generating second key information for decrypting information, wherein the control is performed only for the reproduction apparatus specified by the identification information included in the control information. By permitting the reproduction of the content information based on the information, a reproduction apparatus for reproducing the content information recorded on a recording medium such as a DVD can be controlled by broadcasting based on a viewing contract. It can be viewable digitized work recorded on a recording medium an equal viewing of (content information) only to the contract period.

[0015] The playback apparatus of the present invention provides encrypted control information including at least first key information for decrypting at least the encrypted content information associated with each piece of content information broadcasted. A reproduction device that reproduces encrypted content information recorded on a recording medium, based on key generation information necessary to generate second key information for decrypting the encrypted control information. Decrypting means for decrypting the encrypted control information using second key information generated based on the key generation information; and first key information included in the control information decrypted by the decrypting means. Playback means for decrypting and playing back the encrypted content information recorded on the recording medium using the playback means, wherein the playback means is distributed to control a broadcast wave receiving operation based on a viewing contract. To enable reproduction of the encrypted content information recorded on a recording medium such as a DVD based on the license information broadcast and distributed only during the viewing contract period of the content information. Cut off.

Further, the reproducing apparatus of the present invention comprises: first key information for decrypting at least the encrypted content information associated with each of the pieces of broadcast-distributed content information; Based on encrypted control information including information and key generation information necessary to generate second key information for decrypting the encrypted control information. A decryption device for decrypting the encrypted control information using second key information generated based on the key generation information, and a decryption device configured to decrypt the encrypted control information by using the second key information generated based on the key generation information. Playback means for decrypting and playing back the encrypted content information recorded on the recording medium using the first key information included in the control information, wherein the playback means is configured to execute the playback before the control information is included in the control information. By judging whether or not the content information can be reproduced based on the identification information, the reproduction of the encrypted content information recorded on a recording medium such as a DVD can be performed based on the license information broadcasted. Only possible.

[0017]

Embodiments of the present invention will be described below with reference to the drawings. (1) Outline of Information Distribution Service FIG. 1 shows an example of a system configuration for providing an information distribution service according to an embodiment of the present invention. Content information as a digitized work (for example, a movie) is encrypted, recorded on a recording medium (for example, a DVD-ROM) 5 such as a DVD-ROM, and rented. Distributed through operating companies.

The headquarters of the rental company distributes a DVD-ROM in which, for example, encrypted content information for each title is recorded to each affiliated store. The customer cannot view the content information simply by purchasing the DVD-ROM in which the content information of the desired title is recorded. Key information (hereinafter, content key) for decrypting and reproducing the encrypted content information recorded on the DVD-ROM is required. This content key is encrypted and distributed by satellite broadcasting from the satellite broadcasting station 200 affiliated with the headquarters of the rental company to the receiving device 100 owned by each customer.

[0019] The customer can obtain the D of the content information at the affiliated store.
When a VD-ROM is purchased, a fee corresponding to at least a viewing contract that defines a viewing period is paid. It is an object of the present invention to enable the customer to view the content information recorded on the DVD-ROM on the DVD-ROM playback device 10 owned by the customer based on the viewing contract.

A content key for decrypting the encrypted content information recorded on the DVD-ROM is specifically (in the following description) a partially encrypted license distributed by satellite broadcasting. Information (described below).

In the case of the present embodiment, the license information is generated by, for example, a contract management device installed at the head office of the rental company. The license information distributed by satellite broadcast received by the receiving device 100 (preferably an existing one) is input to the reproduction device 10 of the customer, and is distributed separately by satellite broadcast, for example. The encrypted part of the license information is decrypted with the master key generated based on the master key seed, and a predetermined determination process (details will be described later) is executed, so that the license information within the effective range of the viewing contract made by the customer is obtained. When it is determined that the content information can be viewed, the encrypted content information recorded on the DVD-ROM is decrypted using the content key included in the license information and reproduced. . Conversely, unless valid license information is input to the playback device 10, the encrypted content information recorded on the DVD-ROM cannot be decrypted.

The license information distributed by satellite broadcasting is received by each broadcast receiving device 100. That is,
Customers who want to use the information distribution service of the present invention,
For example, as in the case of receiving a conventional satellite broadcast receiving service, a contract for receiving the satellite broadcast must be made in advance. Otherwise, the broadcast receiving apparatus 100 cannot correctly acquire the license information.

The license information received by the broadcast receiving device 100 is sent to the reproducing device 10. The playback device 10 stores the input license information in a license information storage unit inside the playback device.

The license information may be repeatedly broadcast according to an appropriate schedule. This schedule method will be described later. The license information may include expiration date information of the license information.

Next, an outline of the information distribution service according to the present invention will be described. A customer who intends to use the information distribution service according to the present invention purchases a DVD playback device 10 adapted to the service, and further obtains a content having a desired title from an affiliated store of a business company providing the information distribution service. It is assumed that a DVD-ROM on which information is recorded is obtained.

For example, as shown in FIG. 2, encrypted content information is recorded on the DVD-ROM. DV in which content information of a desired title is recorded
Even if a D-ROM is purchased, the content information is encrypted and cannot be viewed as it is.
Therefore, the DVD-RO on which the content information is recorded
When purchasing M, it is not always necessary to pay a fee corresponding to the copyright. In other words, a customer who intends to use the information distribution service according to the present invention may, for example, use “DVD-R
It becomes possible to obtain a DVD-ROM at a very low price, such as "OM itself price + commission".

The customer inserts the purchased DVD-ROM into D
When inserted into the VD playback device 10 and instructed to play back, the DVD
The license information storage unit of the playback device 10 searches for license information that matches the ID of the content information.
If there is no initial license information, the DVD-
No content information is reproduced from the ROM. If there is license information corresponding to the content ID, the DVD playback device 10 checks the validity of the license information. When the license information is not valid, such as when the expiration date has passed, the DVD reproducing device 10 does not perform decoding and reproduction of the content information. On the other hand, if the license information is valid, the DVD reproducing device 10 decodes and reproduces the content information.

As described above, the fee for viewing the content information of the customer (that is, the fee corresponding to the copyright) is replaced by the satellite broadcasting reception contract fee. A customer who intends to use the information distribution service first signs a broadcast reception contract, and pays, for example, a fixed monthly fee for reception. Next, the receiving subscriber selects content information of a desired title at the affiliated store of the rental business company. As described above, in order to obtain the recording medium on which the encrypted content is recorded, it is only necessary to pay about “the price of the recording medium itself + the commission”. Thereafter, the customer can freely reproduce the brought back content information on the DVD reproducing device 10 according to the receiving contract. This is because the latest valid license information is supplied from the broadcast receiving device 100 to the DVD reproducing device 10.

For example, the license information (eg, information corresponding to the content information of the content ID “# 21243”) distributed by 23:59 on July 7 by broadcast distribution of the license information is 23:00 on July 14th. Assume that it has an expiration date of 59 minutes. Content ID "# 2124
The license information corresponding to the content information "3"
Those with an expiration date of 23:59 on March 21
It is broadcast from 0:00 on July 8 to 23:59 on July 14 and stored in the DVD playback device 10. Thus, the customer can reproduce the content information with the content ID “# 21243” at any time.

Now, when the subscriber of the broadcast cancels the receiving contract on July 22, the cancellation of the contract is notified on July 1.
Notify the rental company by 4 days. If so, the receiving device 100 of the customer stops receiving the license broadcast at 23:59 on July 14. In this case, July 1
The license information of ID “# 21243” having an expiration date of 23:59 on July 28, which is broadcast after 0:00 on May 5, is not distributed to the receiving device 100, and the customer's D
It is not stored in the VD playback device 10.

Therefore, the customer is on July 21 at 23:59.
After the minute, the content information with ID “# 21243” cannot be viewed. Hereinafter, a system for providing an information distribution service according to the present invention will be described more specifically.

In the DVD-ROM, as shown in FIG.
Content information encrypted with the content key, identification information (content ID) of the content information, and promotion information for introducing the content of the content information are recorded. The content ID and the promotion information are not encrypted. Note that the content key is different for each piece of content information. Further, it is assumed that the content ID is assigned, for example, one by one for each title. Further, the content key is predetermined for each title.

FIG. 3 shows a specific example of the data format of the license information. FIG. 3A shows identification information (ID) for identifying each of the playback devices of the customers who have received a contract for receiving the license information. (B) shows license information in the case where a terminal ID for limiting the playback device that receives the license information is included.

The license information shown in FIG. 3A is generated one for each title of the content information, and includes at least the content ID and the content key of the title. The content ID is not encrypted, and the other information (at least the content key) is encrypted with the master key.

When the license information as shown in FIG. 3A is used, the management of the viewing period for each customer is performed, for example, in the same manner as in the conventional satellite broadcast reception contract management. On the other hand, it may be performed by sending a signal (ON / OFF signal) for controlling whether broadcast waves can be received. That is, for example, an ON signal is broadcast-distributed to the broadcast receiving device 100 of the customer at the start of the viewing period of the customer, and the broadcast receiving device 100 of the customer is distributed at the end of the viewing period.
Broadcast distribution of the OFF signal. Broadcast receiving device 100
Receives the ON signal distributed to the broadcast receiving apparatus, and starts the reception of the broadcast wave, and controls the reception of the OFF signal to disable the reception of the broadcast wave.

The license information shown in FIG. 3B includes at least a content ID of the title, a content key, and a terminal ID for specifying a reproducing apparatus that receives the license information. The content ID is not encrypted, and the other information (at least the content key and the terminal ID) is encrypted with the master key.

In the license information shown in FIG. 3B, only one terminal ID of each playback device is described as a terminal ID, and the license information is generated and distributed for each customer. Alternatively, for example, the last few digits of the terminal ID may be described as the terminal ID so that a plurality of playback devices can receive the terminal ID at one time. Needless to say, the latter is more efficient in distributing license information.

When the license information shown in FIG. 3B is used, the management of the viewing period for each customer is performed, for example, by using the reproduction apparatus 10 of the customer whose contract ID has expired in the terminal ID of the license information.
Can be performed by not describing the terminal ID. In this case, each of the playback devices 10 compares the terminal ID included in the license information with its own terminal ID to check whether to import the license information. During the contract period, the terminal ID of the terminal itself is described, or license information including the terminal ID of the terminal is frequently distributed, but from the time when the contract period expires, the terminal information of the terminal is described in the license information. Disappears. Therefore, the playback device 1
0 means that no valid license information can be obtained
The encrypted content information recorded on the D-ROM cannot be decrypted or reproduced.

For encrypting the license information, it is desirable to use an encryption method having the following features. 1) Data such as a content ID and a content key are arranged in an appropriate order. Here, each data may be called a field.

2) According to a suitable algorithm:
Disturb the order of the bit strings. At this time, it is desirable that pit disturbance be performed in a wide range. 3) Encrypt the data of 2) with an appropriate key and encryption method. The reason that 1) is not directly encrypted is as follows. That is, in the normal encryption method, encryption is repeated for each predetermined appropriate bit length. Therefore, by performing the disturbance of 2), it is possible to reduce the risk that each field of the license information is separated or altered.

(2) Contract Management Apparatus FIG. 4 shows an example of the configuration of the contract management apparatus according to the present embodiment, which is installed and used in the ground station 200 in FIG.

The ground station 200 is connected to the station shown in FIG.
The license information and the master key seed as shown in FIG. Content I in the license information
Parts other than D are encrypted with the master key. It is preferable that the master key be updated at regular intervals in order to improve the confidentiality of the license information. Therefore, information necessary for generating a master key in the playback device 10, that is, a master key seed is broadcast-distributed (periodically or when the master key is updated).

The contract management apparatus shown in FIG. 4 is for generating and encrypting license information for broadcast distribution. When a broadcast receiving contract is made with a customer, the contents of the contract (content ID, viewing period, etc.) are registered in the contract user database (DB) 1.

Data is stored in the contract user DB 1 in the format shown in FIG. In FIG. 5, the receiving terminal ID is the terminal ID of the playback device 10 owned by the customer, and the content ID for which the viewing contract has been made and the viewing period are stored in a predetermined format corresponding to the terminal ID.

The seed database (DB) 3 stores the master key generated from the master key seed for master key generation together with its seed ID and expiration date in FIG.
Is stored in the format shown in. Seed DB3 contains seed I
A master key seed corresponding to D may also be stored.

Content key database (DB) 4
Stores a content key for each title in a format shown in FIG. 7 in association with a content ID. Next, FIG.
A procedure for generating the license information as shown in FIG. 8B and transmitting the generated license information to the receiving device using the broadcasting device 13 will be described with reference to the flowchart shown in FIG.

The license information generation controller 9 sends a license information generation instruction to the license information generator 8 (step S11). This instruction is, for example, "199
Send the license information of the contract user who has contracted for one month from December 1, 1995 ", and may be represented by a bit string in a predetermined format. When such an instruction is issued, the license information generation unit 8 searches the contract user DB 1 for user information (see FIG. 5) contracted for at least one month from December 1, 1997, and reads the information (see FIG. 5). Step S12 to Step S
13).

Here, the minimum unit of the contract period is one month,
The contract expiration date starts at one day and ends at the end of the month, and the master key is also unique to this minimum contract period. That is, the master key for November is different from that for December, and is not changed in each month.

Next, the additional information generation unit 8 searches the content key DB 4 for a content key for each content ID (step S 15), and searches the seed DB 3 for 199.
A master key corresponding to a valid seed is searched for from December 1, 2007 to December 31, 1997 (step S1).
6).

The information (content I
D, the content key corresponding to the content ID, the contract content of each user), the additional information generation unit 8 generates license information as shown in FIG. Encrypt (step S17).
The license information generated here is sequentially sent to the additional information generation control unit 9 and the broadcasting device 13.

The broadcast device 13 converts the license information into a broadcast wave of a predetermined frequency band and broadcasts the broadcast to the receiving device (step S18). Scheduling unit 14
When distributing the license information stored in the license information DB 5 or distributing the master key seed, the distribution control is performed such that the receiving device on each user side receives the license information and the master key seed reliably. Is what you do.

That is, for example, after receiving a contract, when changing a contract, when canceling a contract, and when transmitting license information for a content ID of a popular title, it is necessary to frequently transmit the license information. The scheduling unit 14 controls distribution of license information in accordance with the scheduling of distribution of license information.
It is.

The license information generated by the license information generating section 8 may include a time stamp indicating the distribution date and time. The date and time indicated by the time stamp is clock 1
As accurate as possible, timed at 5,
The playback device 10 can set a reference time used for various determination processes. The time stamp is of course not encrypted.

When using license information as shown in FIG. 3A, it is not necessary to search the contract user DB1. That is, the license information generation unit 8 having received the instruction to generate the license information in step S11 of FIG. 8 proceeds to step S15, searches the content key DB4 for a content key for each content ID,
From December 1, 1997 to December 31, 1997, a master key corresponding to a valid seed is searched (step S16), and license information as shown in FIG. The information is encrypted (step S17).

The master key seed corresponding to the master key used for encrypting the license information is distributed at the same time as the distribution of the license information or appropriately.

(3) Reproducing Apparatus FIG. 9 shows an example of the configuration of the reproducing apparatus 10 according to the present embodiment, and FIG. 10 shows an example of the configuration of the license determination unit 208 of the reproducing apparatus 10. .

Hereinafter, the components of the playback apparatus 10 and the license determination unit 208 and their operations will be described with reference to the flowcharts shown in FIGS. The broadcast receiving apparatus 100 receives the broadcast wave from the ground station 200, and inputs the broadcast-distributed license information and the master key seed to the filter 202 of the reproducing apparatus 10 (Step S21).

The filter 202 separates the license information from the master key seed. If the license key is the master key seed, the license information is transferred to the license judging unit 208. If the license information is the license key, the license information is stored in the license information storage unit 2.
04 (steps S22 to S25).

In the license determination unit 208, the master key generation unit 801 generates a master key from the master key seed and stores it in the master key storage unit 802 (step S26). When generating a master key, a master key as a shared key may be generated from a master key seed using the same algorithm determined in advance with the contract management apparatus. The master key generation unit 801 of the license determination unit 208
Then, each time a new master key seed is input, it is used to generate a master key and overwrite the previous master key stored in the master key storage unit 802 and hold it. Every time the master key is updated, an updated new master key can be obtained.

The license information storage unit 204 stores the input license information for each content ID. That is, every time the license information is input, the content ID included therein is checked, and if the license information of the same content ID is already stored, the license information is overwritten. If the time stamp is included in the license information, the date and time indicated by the time stamp are checked, and after a predetermined period of time is discarded, overwriting with newly input license information can be performed.

When a DVD disk is inserted into the reproducing apparatus 10 (step S31), the DVD drive 206
Reads the content ID from the disc and transfers it to the license information selection unit 207 (step S32). The license information selection unit 207 searches the license information storage unit 204 for license information having the content ID (step S33). When there is license information having the content ID,
It is transferred to the license determination unit 208 (steps S34 to S35). When the license information having the license ID is not found, or
If it can be determined that it is invalid (expired) from the time indicated by the time stamp, the subsequent processing is stopped.

The decryption unit 804 of the license determination unit 208 decrypts the license information transferred from the license information selection unit 207 using the master key stored in the master key storage unit 802 (step S3).
6).

Here, the determination processing in the determination unit 805 of the license determination unit 208 in the case of license information as shown in FIG. 3B will be described. In this case, the determination unit 805 checks whether the own terminal ID stored in the ID storage unit 803 matches or is included in the terminal ID included in the decrypted license information. If the terminal ID matches the terminal ID or the terminal ID is included, the license information is determined to be valid, and the content key included in the decoded license information is transferred to the decoder (eg, MPEG2 decoder) 209. (Steps S37 to S
38). Otherwise, the license information is determined to be invalid, and the subsequent processing is stopped.

Next, a description will be given of a determination process in the determination unit 805 of the license determination unit 208 in the case of license information as shown in FIG. in this case,
The determination unit 805 does not need to perform any particular determination process, and transfers the content key included in the decrypted license information to the MPEG2 decoder 209 as it is (steps S37 to S38). In this case, the management of the viewing period for each customer is performed by, for example, a signal (ON / OF) for controlling whether or not broadcast waves can be received by each broadcast receiving apparatus 100, as in the case of conventional satellite broadcast reception contract management.
F signal), once the broadcast receiving apparatus 100 receives the OFF signal, it is turned ON thereafter.
This is because the broadcast wave receiving operation is not performed until the signal is received again.

The DVD drive 206 reads the encrypted content information from the DVD disk and transfers it to the MPEG2 decoder 209 (step S3).
9).

The MPEG2 decoder 209 decrypts the encrypted content information using the content information transferred from the license judging unit 208, further D / A converts the content information and outputs it to a predetermined display device (step S).
40 to step S41).

If the license information includes a time stamp, and the license determination unit 208 has a clock, the determination unit 805 determines the date and time indicated by the time stamp and the clock. The license information is compared with the time and date
Invalidity may be determined. Further, the time of the clock may be set using the time information indicated by the time stamp included in the license information. These detailed processing operations are described in Japanese Patent Application No. 9-122511.

[0068]

As described above, according to the contract management apparatus of the present invention, a reproducing apparatus for reproducing content information recorded on a recording medium such as a DVD can be controlled by broadcasting based on a viewing contract. Of a digital work (content information) recorded on a recording medium of this type can be viewed only during the contract period.

Further, according to the reproducing apparatus of the present invention, the reproduction of the encrypted content information recorded on the recording medium such as the DVD is limited to the viewing contract period of the content information based on the license information broadcast. And make it possible.

[Brief description of the drawings]

FIG. 1 is a diagram showing an example of a system configuration for providing an information distribution service according to an embodiment of the present invention.

FIG. 2 shows a DVD-R recorded with content information, for example.
FIG. 3 is a diagram illustrating a configuration example of recording data of a recording medium such as an OM.

FIG. 3 is a diagram showing a data configuration example of license information.

FIG. 4 is a diagram showing a configuration example of a contract management device.

FIG. 5 is a diagram showing a data configuration example of user information stored in a contract user DB.

FIG. 6 is a diagram showing a data configuration example of information stored in a seed DB.

FIG. 7 is a diagram showing a data configuration example of information stored in a content key DB.

FIG. 8 is a flowchart for explaining the operation of the contract management device of FIG. 4;

FIG. 9 is a diagram showing a configuration example of a playback device.

FIG. 10 is a diagram showing a configuration example of a license determination unit in FIG. 9;

FIG. 11 is a flowchart for explaining the operation of the playback device of FIG. 9 and the license determination unit of FIG. 10;

FIG. 12 is a flowchart for explaining the operation of the playback device of FIG. 9 and the license determination unit of FIG. 10;

[Explanation of symbols]

 Broadcast management device 1 Contract user database 3 Seed database 4 Content key database 5 License information database 8 License information generation unit 9 License information generation control unit 12 License information output request unit 13 Broadcast device 14 Scheduling unit Playback device 202 filter 204 license information storage unit 206 DVD drive 207 license information selection unit 208 license determination unit 209 MPEG decoder 801 master key generation unit 802 master key storage unit 803 ID storage unit 804 decryption Unit 805: Judgment unit

Claims (5)

[Claims] 1. A contract management apparatus for controlling a reproduction apparatus for reproducing encrypted content information recorded on a recording medium by broadcasting based on a viewing contract, wherein the contract management apparatus is associated with each piece of content information. Encrypted control information including first key information for decrypting at least the encrypted content information, and second key information required for decrypting the encrypted control information. Contract management, comprising means for broadcasting distribution of key generation information, and controlling the reproduction operation of the reproduction apparatus by a signal distributed to control the reception operation of the broadcast wave based on the viewing contract. apparatus. 2. A contract management device for controlling a reproduction device for reproducing encrypted content information recorded on a recording medium by broadcasting based on a viewing contract, wherein the contract management device is associated with each of the individual content information. Encrypted control information including first key information for decrypting at least the encrypted content information and identification information of the playback apparatus, and second control information for decrypting the encrypted control information.
Means for broadcasting distribution of key generation information necessary for generating the key information of the content information, and only for the playback device specified by the identification information included in the control information, A contract management device wherein reproduction is permitted. 3. The contract management apparatus according to claim 1, wherein the key generation information is updated every predetermined period. 4. Encrypted control information including at least first key information for decrypting at least the encrypted content information associated with each of the individual pieces of content information broadcasted, and the encrypted control information. A key generating information necessary for generating second key information for decrypting the control information, wherein the key generating information is used for reproducing encrypted content information recorded on a recording medium. Decryption means for decrypting the encrypted control information using second key information generated based on the information; and recording using the first key information included in the control information decrypted by the decryption means. Playback means for decoding and playing back the encrypted content information recorded on the medium, wherein the playback means is controlled by a signal distributed to control a broadcast wave receiving operation based on a viewing contract. Contract management apparatus, characterized in that. 5. An encrypted encrypted content including at least first key information for decrypting at least the encrypted content information associated with each of the pieces of content information broadcast and distributed, and identification information of the playback device. Reproduction of reproducing the encrypted content information recorded on the recording medium based on the generated control information and key generation information necessary for generating second key information for decrypting the encrypted control information. An apparatus, comprising: decryption means for decrypting the encrypted control information using second key information generated based on the key generation information; and first means included in the control information decrypted by the decryption means. Reproducing means for decrypting and reproducing the encrypted content information recorded on the recording medium by using the key information of the above, wherein the reproducing means is configured to perform the decoding based on the identification information included in the control information. Contract management apparatus characterized by determining whether the reproduction of the Ceiling information.