JPH11250571A - Information distributing device, terminal device and information distributing system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an information distributing device, terminal device, and an information distributing system by which unauthorized copy to an other recording medium and use without permission can surely be prevented. SOLUTION: A distributing device 201 is constituted with a card reading means 211 reading information of an IC card 204, a reading means 213 reading information of a DVD-RAM. a recording means 215 recording information in the DVD-RAM, a Kw ID table 214 converting an ID number to a cipher key Kw, and a ciphering means 212 ciphering information, and a terminal device 20 is constituted with a card recording means 221 recording information in the IC card 204, a memory 226 having a public key Kp and a secret key Ks, a reading and separating means 223 reading information of the DVD-RAM and separating it, decipherers 225, 227, deciphering ciphered information, and a comparing means 224 comparing two IDs.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information distribution device, a terminal device, and an information distribution system for distributing a recording medium on which an encrypted content such as a movie is recorded and for purchasing and using the content. is there.

[0002]

2. Description of the Related Art In recent years, information such as movies and images has been recorded on CD-Rs.
There has been proposed a method of recording data on a recording medium such as an OM or a DVD-RAM and selling it to a user. At this time, in order to prevent unauthorized use or unauthorized use of the information, the information to be recorded is encrypted so that movies and videos cannot be viewed without a key to decrypt the code, and only the person who paid the code The key to unlock the key is obtained and the recorded information can be used. Therefore, the encrypted information recorded on the recording medium cannot be used even if unauthorized copying or unauthorized use is attempted unless a key for decrypting the encrypted information is obtained by some method.

[0003]

However, in such a method, the decryption key must be transmitted from the distributor to the user as in the case of the recording medium on which the encrypted information is recorded. There is a possibility that the key itself may be copied or an unauthorized copy may occur. In such a case, there is a problem that it is impossible to prevent the unauthorized use or unauthorized use of the key.

An object of the present invention is to provide an information distribution device, a terminal device, and an information distribution system that can reliably prevent unauthorized copying to other recording media and unauthorized use in consideration of the above-described conventional problems. Is what you do.

[0005]

According to the first aspect of the present invention, there is provided key reading means for reading an ID number and a public key Kp from an information recording medium having an ID number unique to a recording medium and having a public key Kp recorded thereon, An information distributing apparatus comprising: an encrypting unit for encrypting the read ID number and predetermined information with a read public key Kp; and a recording unit for recording the encrypted ID number and predetermined information on an information recording medium. It is.

According to a second aspect of the present invention, there is provided the information distribution apparatus according to the first aspect, wherein an ID number, an encrypted ID number, and an ID number encrypted from a public key Kp are recorded on an information recording medium on which predetermined information is recorded. Encryption reading means for reading the encrypted predetermined information, decoding means for decoding the read encrypted ID number and the predetermined information by using the secret key Ks corresponding to the public key Kp, and the decoding ID number thereof A terminal device comprising: an ID comparing unit that compares the ID number with the ID number; and, when the ID numbers match as a result of the comparison, a determining unit that determines that the decoded predetermined information is appropriate.

According to a fourth aspect of the present invention, there is provided an ID unique to a recording medium.
ID to read ID number from information recording medium with number
Reading means, key reading means for reading the public key Kp from the key recording medium on which the public key Kp is recorded, encryption means for encrypting the ID number and predetermined information read by the read public key Kp, and An information distribution apparatus comprising: an encrypted ID number; and recording means for recording predetermined information on an information recording medium.

According to a fifth aspect of the present invention, there is provided the information distribution apparatus according to the fourth aspect, wherein the ID number, the encrypted ID number, Cipher reading means for reading the encrypted predetermined information, key decoding means for decoding the read encrypted ID number and the predetermined information by using the secret key Ks corresponding to the public key Kp, A terminal device comprising: an ID comparison unit that compares a number with an ID number; and a determination unit that determines that the decoded predetermined information is appropriate when the comparison result shows that the ID numbers match.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings showing an embodiment. (First Embodiment) FIG. 1 is a configuration diagram illustrating functions of an information distribution apparatus and a terminal device according to a first embodiment of the present invention. In FIG. 1, for example, a DVD-RAM 1
03 as a recording medium, and the DVD-RAM 103
The information distribution system includes a distribution device 101 that records information such as a movie (hereinafter referred to as distribution information) and distributes the distribution information to users, and a terminal device 102 that reproduces distribution information recorded on a DVD-RAM 103 purchased by the user. It is configured.

[0010] Here, the terminal device 102 is built in such a state that a secret key Ks serving as a decryption key of the public key cryptosystem cannot be read, and the DVD-RAM 103 has a uniquely determined ID number and secret number unique to a recording medium. A public key Kp for encryption paired with the key Ks is recorded. Here, Ks and Kp are terminal-specific. Further, the distribution information may be encrypted with a normal encryption key Kw and may be recorded in advance, or may be recorded at the time of distribution.

Next, the operation of the information distribution device and the terminal device of the above embodiment will be described with reference to the drawings.

When distributing user distribution information, the distribution apparatus 101 first reads the ID number and the public key Kp of the DVD-RAM 103, and encrypts the ID number and the encryption key Kw with the public key Kp. This encrypted one is represented by Kp [ID, Kw] for convenience. Here, it is assumed that the distribution apparatus 101 has a conversion table of the encryption key Kw and the ID number, and the encryption key Kw is generated based on the read ID number. When the distribution information is recorded in advance, the conversion table has a conversion function for specifying the encryption key Kw which has encrypted the pre-recorded information from the ID number. Next, the encrypted Kp [ID, Kw]
Is recorded on the DVD-RAM 103. Kw [DATA] obtained by encrypting the distribution information with the encryption key Kw is also a DVD-RA
It is recorded in M103.

Next, the user operates the DVD-RAM in this state.
103 and purchases the DV using the terminal device 102 that the user owns.
The D-RAM 103 is reproduced. In the terminal device 102, first, the ID number and Kp [ID, Kw] are read from the purchased DVD-RAM 103, and the read K
It decrypts p [ID, Kw] using the built-in secret key Ks. Next, the decrypted ID is compared with the ID read directly from the DVD-RAM 103. If the comparison result matches, the DVD-RAM 103 is decrypted using the decrypted encryption key Kw.
And decodes Kw [DATA] read from the TV, and views the TV through an AV decoder not shown.

At this time, if the comparison results do not match, I
Since the D number is unique to each recording medium, it can be determined that the information has been copied to another DVD-RAM.
Decryption with the encryption key Kw is stopped.

It is preferable that the distribution information is encrypted by Kw using a common key cryptosystem. As a result, decryption of a public key that requires a large amount of calculation for decryption can be performed by Kw
Only when obtaining the information, a large amount of information such as a movie can be easily decoded. (Second Embodiment) FIG. 2 is a configuration diagram illustrating functions of an information distribution apparatus and a terminal device according to a second embodiment of the present invention. In FIG. 2, for example, a DVD-RAM2
03 as an information recording medium, and the DVD-RAM2
03, a distribution apparatus 201 that records information such as a movie (hereinafter referred to as distribution information) and distributes the distribution information to users, and distribution information Kw recorded on a DVD-RAM 203 purchased by the user.
An information distribution system is configured by the terminal device 202 that reproduces [DATA]. In the present embodiment, unlike the above-described first embodiment, the public key Kp is stored in the DVD-RA
Instead of M203, the user uses the terminal device 202,
For example, a method of recording the information on a recording medium (hereinafter referred to as a key recording medium) using the IC card 204 or the like and providing the recording medium to the distribution apparatus 201 is used.

Here, the terminal device 202 is built in such a manner that the secret key Ks serving as a decryption key of the public key cryptosystem cannot be read, and the DVD-RAM 203 records a uniquely determined ID number unique to the recording medium. Have been. Also, as described above, the distribution information is encrypted using the normal encryption key Kw,
It may be recorded in advance, or may be recorded at the time of distribution.

FIG. 3 is a block diagram showing the inside of the distribution device and the terminal device according to the present embodiment. Distribution device 201
A card reader 211 as a key reader for reading information recorded on the IC card 204; a reader 213 as an ID reader for reading information from the DVD-RAM 203 driven by the DVD drive 216;
Recording means 21 for recording information on DVD-RAM 203
5, a Kw / ID table 214 for converting an ID number into an encryption key Kw, and an encryption means 212 for encrypting information.

On the other hand, the terminal device 202
4, a card recording unit 221 for recording information, a public key Kp
And a memory 22 for storing a secret key Ks paired therewith.
6. DVD-RAM driven by DVD drive 222
Read separation means 22 for reading and separating information from 203
3. Two decryptors 225 and 22 for decrypting the encrypted information
7, a comparing means (composed of, for example, a microcomputer) 224 for comparing two pieces of information. here,
The reading / separating means 223 constitutes a cipher reading means, the decryptor 225 constitutes a key decrypting means, and the comparing means 224 constitutes
It constitutes D comparison means and determination means.

The DVD-RAM 203 has a ROM area and a RAM area.
Is recorded in the RAM area. Also, the encrypted distribution information Kw [DATA] may be recorded in either the ROM area or the RAM area, but in the case of the ROM area, it is recorded in advance.

Next, the operation of the information distribution device and the terminal device of the above embodiment will be described with reference to the drawings.

When distributing the user distribution information, first, in the terminal device 202, the card recording means 221 reads the public key Kp from the memory 226 and records it on the IC card 204. Next, in the distribution device 201, the card reading means 211 reads the public key Kp from the IC card 204 on which the public key Kp is recorded, and the reading means 213 reads the public key Kp from the DVD-RAM 203 set in the DVD drive 216. The ID number of the DVD-RAM 203 is read.

The public key Kp read by the card reading means 211 is sent to the encryption means 212, and the ID number read by the reading means 213 is sent to the Kw / ID table 214 and the encryption means 212. In the Kw / ID table 214, an encryption key Kw for encrypting distribution information is generated based on the ID number, and the generated encryption key Kw
To the encryption means 212. Next, the encryption unit 212
Encrypts the ID number and the encryption key Kw with the public key Kp, and stores the encrypted Kp [ID, Kw] in the recording unit 21.
Send to 5. The recording means 215 stores the encrypted Kp
[ID, Kw] is converted to a DVD-RA via a DVD drive.
It is recorded in the RAM area of M203. At this time, as described above, the distribution information is encrypted with the encryption key Kw, and Kw [DA
TA] is also recorded on the DVD-RAM 203.

Next, the user operates the DVD-RAM in this state.
203 is converted to a DVD-R using the own terminal device 202.
Play AM 203. In the terminal device 202, first, the reading / separating means 223 reads the ID number and Kp [ID, Kw] from the purchased DVD-RAM 203 via the DVD drive 222, and separates the information. At this time, Kw [DATA] is also read and separated. The separated ID number is sent to the comparison means 224 by Kp
[ID, Kw] is sent to the decoder 225, and Kw [DATA] is sent to the decoder 227.

The decryptor 225 receives the public key K from the memory 226.
The secret key Ks paired with p is read, the encrypted information Kp [ID, Kw] is decrypted with the secret key Ks, the ID number is sent to the comparison means 224, and the encryption key Kw is sent to the decryptor 227. The comparing means 224 compares the ID number from the reading / separating means 223 with the ID number decoded by the decoder 225, and outputs an ON / OFF signal according to the comparison result.
Send to 27. That is, if the two ID numbers match, O
An N signal is output, and if they do not match, an OFF signal is output.

The decoder 227 outputs the signal to the decoder 2 when the signal is ON.
25, the encrypted distribution information Kw
It decodes [DATA] and outputs AV data such as a movie. AV data is transmitted through an AV decoder (not shown) to T
Appreciate by V.

As in the case of the first embodiment,
If the comparison result of the ID numbers does not match, the information is stored in another DVD-R because the ID number is unique to each recording medium.
Since it can be determined that it has been copied to the AM, the encryption key Kw
Is stopped.

As described above, according to the present invention, the DVD-R
The original and copy of the AM can be determined.
In order to make it difficult to escape this determination, an ID that cannot be copied by a commercially available device (for example, ROM)
Or in an area that can be written only once).

Here, it is assumed that a third party attempts to acquire information by copying the information recording medium described above, instead of the original, regardless of the terminal described above (hereinafter referred to as an appropriate terminal). explain.

For example, in the case where a device capable of copying all the unique IDs of the DVD-RAM is used, if the copy made in this way is to be reproduced on another terminal having a different Ks, the ID or Kw is changed. Since decoding cannot be performed correctly, information cannot be obtained.

On the other hand, even if the same Ks can be given to another terminal due to the unauthorized disclosure of the Ks of a specific terminal, the copy is performed as long as the copy determination function of the present invention operates. Information cannot be obtained from the information distribution medium generated by the above.

As described above, since the distribution method of the present invention has both the function of preventing distribution medium copy and the function of specifying the user terminal, it is possible for a third party to make unauthorized copies or use it on other terminals without permission. This makes it extremely difficult to illegally obtain information, and has the effect of preventing the act of illegally distributing a copy of information to an unspecified number of terminals. (Third Embodiment) FIG. 4 is a block diagram showing an information distribution apparatus and a terminal device according to a third embodiment of the present invention. The DVD-RAM used in the present embodiment has a recording form as shown in FIG. 5, in which distribution information is divided into a plurality of pieces, and the divided pieces of information have different encryption keys K.
1 to K4, and each of the encryption keys K1 to K4 is encrypted with the encryption key Kw. That is, it is doubly encrypted. Further, a title name is recorded as identification information corresponding to the recorded distribution information.

In FIG. 4, the DVD-RAM 30 shown in FIG.
3 as an information recording medium, and the DVD-RAM 30
3 is a distribution device 301 that records information such as a movie (hereinafter referred to as distribution information) and distributes it to users, and a terminal device 302 that reproduces distribution information recorded on a DVD-RAM 303 purchased by the user. Is configured. In the present embodiment, the public key Kp is stored in the IC card 304 using an ID number unique to the IC card 304 as a key recording medium.
The information is recorded on the card 304 and provided to the distribution device 301, and the encrypted information is recorded on the IC card 304. This IC card 304 has an ID number recorded in advance.
It has an OM area and a RAM area in which information can be recorded.

The distribution apparatus 301 includes a card reading unit 311 serving as a key reading unit for reading information recorded on the IC card 304 and a D driven by a DVD drive 316.
Reading means 313 as identification information reading means for reading information (title name) from the VD-RAM 303, card recording means 315 as information recording means for recording information on the IC card 304, and information generation for converting the title name into an encryption key Kw Kw / title table 314 as means,
It is composed of an encryption means 312 for encrypting information.

On the other hand, the terminal device 302
4, the card recording means 321 for recording information, the public key Kp
And a memory 32 for storing a secret key Ks paired therewith.
6. DVD-RAM driven by DVD drive 322
Read separation means 32 for reading and separating information from 303
3. Three decryptors 325 and 32 for decrypting the encrypted information
7, 328, comparing means (for example, configured by a microcomputer) 324 as ID comparing means for comparing two pieces of information;
It comprises a card reading means 329 as an encryption reading means for reading information of the IC card 304, and a selecting means 330 for selecting distribution information based on a title name. Here, the decryptor 325 constitutes a decoding unit.

Next, the operation of the information distribution device and the terminal device of the above embodiment will be described with reference to the drawings.

When a user purchases distribution information, first,
In the terminal device 302, the card recording means 321 reads the public key Kp from the memory 326 and records it on the IC card 304 on which the ID number is recorded. Next, the distribution device 30
1, the IC card 3 on which the public key Kp is recorded
04, the card reading means 311 reads the ID number and the public key Kp, and the reading means 313 reads from the DVD-RAM 303 set in the DVD drive 316.
Read the title of the distribution information.

The ID number and the public key Kp read by the card reading means 311 are sent to the encryption means 312, and the title read by the reading means 313 is K
w. Title name table 314 and card recording means 31
Sent to 5. In the Kw / title name table 314,
An encryption key Kw for encrypting the distribution information is generated based on the title name, and the generated encryption key Kw is used as the encryption unit 31
Send to 2. Next, the encryption unit 312 encrypts the ID number and the encryption key Kw with the public key Kp, and sends the encrypted Kp [ID, Kw] to the card recording unit 315. The card recording means 315 stores the encrypted Kp [ID,
Kw] and the unencrypted title name are recorded in the RAM area of the IC card 304. At this time, as described above, the distribution information is divided into four parts and encrypted by the encryption keys K1 to K4, respectively.
Are also encrypted with the encryption key Kw. The number of divisions of the distribution information is not limited to four, and the number of encryption keys may be prepared according to the number of divisions. In FIG. 5, the encrypted distribution information is represented by K1 [DATA] to K4 [DATA].

Next, the user operates the DVD-RAM in this state.
After purchasing the terminal 303 and owning the terminal device 302,
DVD-RAM 30 using information recorded on the card
Play 3 In the terminal device 302, first, the card reading means 329
The D number, the encrypted information Kp [ID, Kw], and the title are read and sent to the selection means 330.

On the other hand, the reading / separating means 323 is connected to the purchased DVD-RAM 303 via the DVD drive 322.
From Kw [K1] to Kw [K4], K1
[DATA] to K4 [DATA] are read, and the information is separated. The separated title name is selected by the selecting means 330
And Kw [K1] to Kw [K4] are transmitted to the decryptor 328
1 [DATA] to K4 [DATA] are sent to the decryptor 327,
Each sent. The selecting means 330 sends the ID number to the comparing means 324, and selects the encryption information Kp [ID, Kw] corresponding to the title name in accordance with the title name from the reading / separating means 323. ,
Kw] to the decryptor 325.

The decryptor 325 receives the public key K from the memory 326.
The secret key Ks paired with p is read, the encrypted information Kp [ID, Kw] is decrypted with the secret key Ks, the ID number is sent to the comparison means 324, and the encryption key Kw is sent to the decryptor 328. The decryptor 328 uses the encryption key Kw to generate the encryption information Kw.
[K1] to Kw [K4] are decrypted and the encryption keys K1 to K4 are output to the decryptor 327.

The comparing means 324 is connected to the selecting means 330
Is compared with the ID number decrypted by the decryption unit 325, and an ON / OFF signal is sent to the decryption unit 327 according to the comparison result. That is, if the two ID numbers match, an ON signal is output, and if they do not match, an OFF signal is output.

The decoder 327 outputs the signal of the decoder 3 when the signal is ON.
With the use of the encryption keys K1 to K4 from the server 28, the encrypted distribution information K1 [DATA] to K4 [DATA] are decrypted and AV data is output. AV data not shown
Watch through TV through the decoder.

As in the case of the first embodiment,
If the comparison result of the ID numbers does not match, the decryption using the encryption key Kw is stopped, and the encryption key Kw and the ID number are carried on a recording medium different from the DVD-RAM, so that the security is further increased. Since the encryption key for encrypting the distribution information is duplicated, the security against unauthorized copying and unauthorized use is further increased. (Fourth Embodiment) FIG. 6 is a block diagram showing an information distribution device and a terminal device according to a fourth embodiment of the present invention. The DVD-RAM used in the present embodiment has a recording form as shown in FIG. 7, and similarly to FIG. 5, the distribution information is divided into a plurality of pieces, and the divided partial information has different encryption keys K1 to K1. K4, and each of the encryption keys K1 to K4 is encrypted with the encryption key Kw.
The difference from FIG. 5 is that the title name is not recorded and RO
An M area is provided, and a DVD-RA
M is recorded with a unique ID number.

In FIG. 6, the DVD-RAM 40 shown in FIG.
3 as an information recording medium, and the DVD-RAM 40
3 is a distribution device 401 that records information such as a movie (hereinafter referred to as distribution information) and distributes it to users, and a terminal device 402 that reproduces distribution information recorded on the DVD-RAM 403 purchased by the user. Is configured. In the present embodiment, similarly to the above-described second embodiment, the user issues the public key Kp using the terminal device 402,
The encrypted information is recorded on an IC card 404 as a key recording medium and provided to the distribution device 401, and the encrypted information is stored in a DVD-RAM.
The method of recording in 403 is adopted.

The distribution device 401 includes a card reading unit 411 as a key reading unit for reading information recorded on the IC card 404, and a D driven by a DVD drive 416.
Reading means 413 as ID reading means for reading information from the VD-RAM 403, recording means 415 for recording information on the DVD-RAM 403, Kw / ID table 41 as information generating means for converting an ID number into an encryption key Kw
4. It is composed of an encryption means 412 for encrypting information.

On the other hand, the terminal device 402
Card recording means 421 for recording information in the public key Kp
And a memory 42 for storing a secret key Ks paired therewith.
6. DVD-RAM driven by DVD drive 422
Read separation means 423 as an encryption key reading means for reading and separating information from 403, 3 for decrypting encrypted information
Each of the decoders 425, 427, and 428 is composed of comparison means (for example, a microcomputer) 424 as ID comparison means for comparing two pieces of information. here,
The decryptor 425 forms a key decryption unit, the decryptor 428 forms an encryption key decryption unit, and the decryptor 427 forms a data decryption unit.

Next, the operation of the information distribution device and the terminal device of the above embodiment will be described with reference to the drawings.

When a user purchases distribution information, first,
In the terminal device 402, the card recording unit 421 reads the public key Kp from the memory 426, and
To record. Next, in the distribution device 401, the card reading means 411 reads the public key Kp from the IC card 404 in which the public key Kp is recorded, and the reading means 413 reads the public key Kp from the DVD-RAM 403 set in the DVD drive 416. The ID number of the DVD-RAM 403 is read.

The public key Kp read by the card reading means 411 is sent to the encryption means 412, and the ID number read by the reading means 413 is sent to the Kw / ID table 414 and the encryption means 412. The Kw · ID table 414 generates an encryption key Kw for encrypting distribution information based on the ID number, and generates the generated encryption key Kw.
To the encryption means 412. Next, the encryption means 412
Encrypts the ID number and the encryption key Kw with the public key Kp, and stores the encrypted Kp [ID, Kw] in the recording unit 41.
Send to 5. The recording means 415 stores the encrypted Kp
[ID, Kw] is converted to a DVD-RA via a DVD drive.
It is recorded in the RAM area of M403. At this time, as described above, the distribution information is divided into four parts and encrypted by the encryption keys K1 to K4, respectively.
4 is also encrypted with the encryption key Kw. The number of divisions of the distribution information is not limited to four, and the number of encryption keys may be prepared according to the number of divisions.

Next, the user operates the DVD-RAM in this state.
Purchase 403 and use the terminal device 402
The D-RAM 403 is reproduced. In the terminal device 402, first, the reading / separating means 423
22 from the purchased DVD-RAM 403
Number, encryption information Kp [ID, Kw], Kw [K1] to K
w [K4] and K1 [DATA] to K4 [DATA] are read, and their information is separated. The separated ID number is sent to the comparing means 424, and Kp [ID, Kw] is sent to the decoder 425.
In addition, Kw [K1] to Kw [K4]
1 [DATA] to K4 [DATA] are sent to the decryptor 427,
Each sent.

Decryptor 425 sends public key K from memory 426
The secret key Ks paired with p is read, the encrypted information Kp [ID, Kw] is decrypted with the secret key Ks, the ID number is sent to the comparison means 424, and the encryption key Kw is sent to the decryptor 428. The decryptor 428 uses the encryption key Kw to generate the encryption information Kw.
It decrypts [K1] to Kw [K4] and outputs encryption keys K1 to K4 to decryptor 427.

Further, the comparing means 424 calculates the ID number from the reading and separating means 423 and the ID decrypted by the decrypting device 425.
The number is compared with the number, and an ON / OFF signal is sent to the decoder 427 according to the comparison result. That is, if the two ID numbers match, an ON signal is output, and if they do not match, an OFF signal is output.

The decoder 427 outputs the signal from the decoder 4 when the signal is ON.
With the use of the encryption keys K1 to K4 from the server 28, the encrypted distribution information K1 [DATA] to K4 [DATA] are decrypted and AV data is output. AV data not shown
Watch through TV through the decoder.

As in the case of the first embodiment,
If the comparison result of the ID numbers does not match, the decryption using the encryption key Kw is stopped, and the encryption key for encrypting the distribution information is duplicated, so that it is more secure against unauthorized copying and unauthorized use. The degree increases. (Fifth Embodiment) FIG. 8 is a diagram showing a recording state on a recording medium according to a fifth embodiment of the present invention. This embodiment is basically the same as the second embodiment, for example, except that an ID number encrypted with a public key Kp and encryption information Kp [I
D, Kw] in the RAM area of the original key recording medium, such as the IC card or the information recording medium, the DVD-RAM 503, instead of another key recording medium, for example, as shown in FIG. Is recorded on a key medium (for example, in a barcode format) provided in a predetermined area of the image forming apparatus. The other key recording medium is DVD-
The provision on the RAM 503 is not particularly limited. (Sixth Embodiment) FIG. 9 is a diagram showing a recording state on a recording medium according to a sixth embodiment of the present invention. In the present embodiment, for example, in the second embodiment, a unique encryption key KID unique to the DVD-RAM (information recording medium) 603 is provided in the ROM area instead of the ID number. Is used.
The encryption key Kw for encrypting the distribution information is encrypted with the encryption key KID, and the encrypted KID [Kw] is further encrypted with the public key Kp, and the encrypted information Kp [KID
[Kw]] is recorded in the RAM area. According to this method, since the encryption key KID is unique to the DVD-RAM, even if the encryption key KID is copied to another DVD-RAM, the read encryption key KID is different. Is stolen, the encryption key Kw cannot be decrypted, and unauthorized use can be prevented.

For example, in the first embodiment, when Ks is exposed and the copy determination function of the terminal is released,
Even if the information recording medium cannot be copied for each unique ID,
There remains the possibility of playing the copy on other terminals. However, in the method using the key KID unique to the recording medium, the information can be illegally reproduced only when the information recording medium is copied for each KID, and the security is further improved.

In the above embodiment, the encryption key is used as the predetermined information to be encrypted with the public key Kp. However, the present invention is not limited to this. For example, charge information (payment information) of the amount of payment may be used. Is also good. Alternatively, both of them may be included. If the fee information is used, only the information corresponding to the paid amount is decrypted, so that even if various types of information are recorded and sold on one information recording medium, the information that can be used by the user and the number of times of use can be limited. When the above-mentioned charge information is used, for example, the terminal apparatus reads and decrypts the encrypted charge information, and then deletes the encrypted charge information. Only if this erase is successful
The decrypted fee information is valid. In this way, the charge information is not reused many times, and illegal use can be prevented. When only a part of the information is used, the fee information needs to be updated. In this case, after subtracting the usage amount from the original fee information, it is encrypted with the same encryption method, the encrypted fee information is overwritten on the original encrypted information, and the fee is only charged if the overwriting succeeds. Validate the information.

In the third embodiment, the title name is used as the identification information. However, the present invention is not limited to this. The identification information may be any as long as it can identify the content of the data to be recorded. And so on.

In each of the above embodiments, a DVD-RAM has been described as an example of an information recording medium. However, the present invention is not limited to this, and may be, for example, a CD-ROM or a CD-R.

In each of the above embodiments, an IC card has been described as an example of a key recording medium. However, the present invention is not limited to this. For example, a magnetic card may be used.

[0060]

As is apparent from the above description, the present invention encrypts an ID number unique to a recording medium and predetermined information by a public key cryptosystem, and records the encrypted ID number with a decrypted ID number. Since it is determined whether the predetermined information is appropriate by comparing the ID number read from the medium with the ID number, there is an advantage that unauthorized copying to another recording medium or unauthorized use can be reliably prevented.

[Brief description of the drawings]

FIG. 1 is a configuration diagram illustrating functions of an information distribution device and a terminal device according to a first embodiment of the present invention.

FIG. 2 is a configuration diagram illustrating functions of an information distribution device and a terminal device according to a second embodiment of the present invention.

FIG. 3 is a block diagram illustrating an information distribution device and a terminal device according to the second embodiment.

FIG. 4 is a block diagram illustrating an information distribution device and a terminal device according to a third embodiment of the present invention.

FIG. 5 is a diagram showing a recording state on a recording medium according to the third embodiment.

FIG. 6 is a block diagram illustrating an information distribution device and a terminal device according to a fourth embodiment of the present invention.

FIG. 7 is a diagram showing a recording state on a recording medium according to the fourth embodiment.

FIG. 8 is a diagram showing a recording state on a recording medium according to a fifth embodiment of the present invention.

FIG. 9 is a diagram illustrating a recording state on a recording medium according to a sixth embodiment of the present invention.

[Explanation of symbols]

101, 201, 301, 401 Distribution device 102, 202, 302, 402 Terminal device 103, 203, 303, 403, 503, 603 D
VD-RAM 204, 304, 404 IC card 212, 312, 412 Encryption means 215, 415 Recording means 223, 323, 423 Read separation means 224, 324, 424 Comparison means 225, 325, 425 Decryptor 227, 327, 427 Decryptor 328, 428 Decryptor

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Masazumi Yamada 1006 Kazuma Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd.

Claims (25)

[Claims] 1. A public key K having an ID number unique to a recording medium.
key reading means for reading the ID number and the public key Kp from an information recording medium on which p is recorded;
An encryption unit for encrypting a D number and predetermined information with the read public key Kp; and a recording unit for recording the encrypted ID number and predetermined information on the information recording medium. Information distribution equipment to do. 2. The information distribution apparatus according to claim 1, wherein the ID number, the encrypted ID number, and the encryption ID are encrypted from the information recording medium on which the ID number encrypted with the public key Kp and predetermined information are recorded. Encryption reading means for reading encrypted predetermined information, decryption means for decrypting the read encrypted ID number and predetermined information using a secret key Ks corresponding to the public key Kp, and a decryption ID number thereof And the ID
ID comparing means for comparing the ID with the ID number, and the result of the comparison, I
A terminal device comprising: a determination unit that determines that the decoded predetermined information is appropriate when the D numbers match. 3. An information distribution system comprising: the information distribution device according to claim 1; and the terminal device according to claim 2. 4. An ID reading means for reading an ID number from an information recording medium having an ID number unique to the recording medium,
From the key recording medium on which the public key Kp is recorded, the public key Kp
Reading means for reading the public key Kp
And an encryption means for encrypting the read ID number and the predetermined information, and a recording means for recording the encrypted ID number and the predetermined information on the information recording medium. apparatus. 5. The information distribution device according to claim 4, wherein the ID number, the encrypted ID number, and the encryption ID are obtained from the information recording medium on which the ID number encrypted with the public key Kp and predetermined information are recorded. Encryption reading means for reading encrypted predetermined information, key decryption means for decrypting the read encrypted ID number and predetermined information using a secret key Ks corresponding to the public key Kp, and a decryption ID Number and I
ID comparison means for comparing with the D number, and the result of the comparison,
A terminal device comprising: a determination unit that determines that the decrypted predetermined information is appropriate when the ID numbers match. 6. An information distribution system, comprising: the information distribution device according to claim 4; and the terminal device according to claim 5. 7. An identification information reading means for reading the identification information from the information recording medium on which the identification information of the data to be recorded is recorded, an information generation means for generating predetermined information based on the identification information, Key reading means for reading the ID number and the public key Kp from the key recording medium on which the medium-specific ID number and the public key Kp are recorded, the read ID number and the predetermined information by the read public key Kp An information distributing apparatus comprising: an encrypting means for encrypting the key information; and information recording means for recording the encrypted ID number and predetermined information and the read identification information on the key recording medium. 8. The information distribution device according to claim 7, wherein the ID number encrypted with the public key Kp, the predetermined information, and the identification information are stored in the key recording medium.
A cipher reading unit that reads a D number, an encrypted ID number, encrypted predetermined information, and identification information; a selection unit that selects an encryption ID number and predetermined information corresponding to the identification information; Decryption means for decrypting the selected encrypted ID number and predetermined information using a secret key Ks corresponding to Kp, ID comparison means for comparing the decrypted ID number with the ID number, A terminal device comprising: a determination unit that determines that the decrypted predetermined information is appropriate according to the identification information when the ID numbers match. 9. An information distribution system comprising: the information distribution device according to claim 7; and the terminal device according to claim 8. 10. An ID reading means for reading an ID number from an information recording medium having an ID number unique to a recording medium; a key reading means for reading the public key Kp from a key recording medium on which a public key Kp is recorded; Key encrypting means for encrypting the read ID number and the predetermined information with the read public key Kp, and recording the encrypted ID number and the predetermined information on a key recording medium different from the key recording medium An information distribution apparatus, comprising: 11. The information distribution apparatus according to claim 10, wherein the another key recording medium is provided at a predetermined location on the information recording medium. 12. The information distribution device according to claim 10 or 11, wherein the encrypted ID number and the encrypted ID number, which are encrypted with the public key Kp, are recorded from the another key recording medium on which the predetermined information is recorded. Cipher reading means for reading encrypted predetermined information; ID reading means for reading an ID number from the information recording medium; and a secret key Ks corresponding to the public key Kp. Decoding means for decoding the predetermined information; ID comparison means for comparing the decoded ID number with the ID number; as a result of the comparison, if the ID numbers match, the decoded predetermined information is A terminal device comprising: a determination unit that determines that there is a terminal device. 13. An information distribution system, comprising: the information distribution device according to claim 10 or 11; and the terminal device according to claim 12. 14. An ID reading means for reading an ID number from an information recording medium having an ID number unique to a recording medium,
From the key recording medium on which the public key Kp is recorded, the public key Kp
Key reading means for reading an ID, an information generating means for generating an encryption key Kw based on the read ID number, an encryption means for encrypting the ID number and the encryption key Kw with the public key Kp, Information recording means for recording an encrypted ID number and an encryption key Kw on the information recording medium, and data recorded on the information recording medium is an encryption key Kw.
a, and the encryption key Ka is encrypted with the encryption key Kw.
An information distribution device, wherein the information is recorded in the information recording medium after being encrypted in the information recording medium. 15. The information distribution apparatus according to claim 14, wherein an ID number and an encryption key Kw encrypted with the public key Kp.
The ID number, the encrypted ID number, the encrypted encryption key Kw, and the encryption key Ka from the information recording medium on which the encryption key Ka encrypted with the encryption key Kw and the data encrypted with the encryption key Ka are recorded. Encryption key reading means for reading the encrypted encryption key Ka, key decryption means for decrypting the read encrypted ID number and the encrypted encryption key Kw using a secret key Ks corresponding to the public key Kp, and decryption thereof Encryption key decryption means for decrypting the encryption key Ka using the encrypted encryption key Kw, and an ID for comparing the decryption ID number with the ID number
Comparing means, and data decrypting means for decrypting the encrypted data recorded on the information recording medium with the decrypted encryption key Ka when the ID numbers match as a result of the comparison. Terminal device. 16. An information distribution system comprising: the information distribution device according to claim 14; and the terminal device according to claim 15. 17. The encrypted data recorded on the information recording medium is divided into a plurality of pieces, and the encryption key Ka is different for each of the divided data. Information distribution system described. 18. Reading means for reading the encryption key KID from an information recording medium having an encryption key KID unique to a recording medium, and key reading means for reading the public key Kp from a key recording medium on which a public key Kp is recorded. Encryption means for encrypting predetermined information with the read encryption key KID, and further encrypting the encrypted predetermined information with a public key Kp; and recording the encrypted predetermined information on the information recording medium. An information distributing apparatus comprising: 19. The information distributing apparatus according to claim 18, wherein the encryption key reading unit reads the encryption key KID and the encrypted predetermined information from the information recording medium on which the encrypted predetermined information is recorded. Key decryption means for decrypting the read encrypted predetermined information using a secret key Ks corresponding to the public key Kp, and further decrypting the decrypted predetermined information with the encryption key KID. A terminal device comprising: 20. An information distribution system, comprising: the information distribution device according to claim 18; and the terminal device according to claim 19. 21. The method according to claim 3, wherein the predetermined information is price information or an encryption key Kw.
21. The information distribution system according to any one of items 3 and 20. 22. The predetermined information is money amount information. After obtaining the money amount information by decrypting the encrypted money amount information with a secret key Ks, the encrypted money amount information is deleted. 22. The information distribution system according to claim 21, wherein the obtained amount information is determined to be valid only when the erasure is successful. 23. Predetermined information is money amount information, and after obtaining the money amount information by decrypting the encrypted money amount information with a secret key Ks, reducing the used amount from the obtained money amount information. Then, the reduced amount information is encrypted by the same encryption method, the original encrypted amount information is updated, and only when the update is successful, the reduced amount is determined to be valid. 22. The information distribution system according to claim 21, wherein: 24. The predetermined information includes at least an encryption key Kw, and data encrypted by the encryption key Kw is recorded on the information recording medium,
3. The apparatus according to claim 2, further comprising: data decryption means for decrypting the data encrypted with the encryption key Kw when the predetermined information is determined to be appropriate by the determination means.
The terminal device according to any one of 5, 8, and 12. 25. The terminal device according to claim 24, wherein the encrypted data is divided into a plurality of data.