JP2000004430A - Pay broadcast reception method and receiver therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pay broadcast receiver without needing pre-paid slots for every broadcast station. SOLUTION: Broadcast stations 101, 102 are respectively provided with a pre-paid card issue section 116 that manages a work key Kw and issues a pre-pair card. A PCMCIA card 7 that applies view control to a pay broadcast receiver 1 is provided with a public key encryption communication authentication section 26 that applies public key encryption communication and authentication to a pre-paid card 15 and stores the work key Kw and pre-paid money information stored in the pre-paid card 15 to a Kw/pre-paid money memory 23 in the PCMCIA card 7. Then a view propriety discrimination section 24 subtracts a program charge in the case of PPV viewing from a pre-paid money balance in the Kw/pre-paid money memory 23.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pay-broadcast receiving method and apparatus, and more particularly, to a pay-broadcast receiving method and apparatus using a prepaid card for payment of a viewing fee such as pay-per-view.

[0002]

2. Description of the Related Art In pay broadcasting, some pay programs are scrambled so that a viewer who has a viewing contract with a broadcasting station can cancel the scramble and view a paid program. FIG. 8 shows a pay broadcast receiving apparatus 1 for viewing such a pay broadcast.
1 shows a conventional example of a pay broadcasting system 500 including the following. In this example, a PCMCIA card 7 is used for viewing management.

[0003] The broadcast station 104 or 105 provides the pay broadcast receiving apparatus 1 with contract information (hereinafter, individual information, EMM) for individual viewers multiplexed on a program. This individual information is information for enabling the receiving apparatus of the contracted party to view the information, and the broadcasting station can provide the information for enabling the viewing only to the receiving apparatus to which the individual information is to be provided. Then, the data is encrypted with an individual key Kmi unique to the receiving device, and ID information for filtering the individual information addressed to the receiving device from among the transmitted individual information is transmitted.

[0004] For this reason, a receiving device that does not have the individual key Kmi cannot take in the encrypted information, and it is not possible to take a fraudulent act of just looking at using information of another person. I have. This individual information is P
It is stored in the CMCIA card and cannot be illegally rewritten.

The individual information also gives a work key Kw. The work key Kw is a key for encrypting the following program information so as not to be used illegally. The information encrypted with the work key Kw is program information (ECM) relating to a program commonly given to the PCMCIA cards of all the receiving devices with the viewing contract, and this program information is information on the program being broadcast and also on the video. And a scramble key Ks which is a key for descrambling information provided in broadcasting such as an audio signal.

[0006] For this reason, the PCM of the receiving device for which there is no viewing contract
With a CIA card, individual information cannot be received from a broadcasting station, and as a result, a work key cannot be obtained. Therefore, a scramble key Ks cannot be finally obtained and cannot be viewed.

[0007] The judgment of the presence or absence of the viewing contract is made by comparing the individual information and the program information in the viewing permission / inhibition judging section 24 in the PCMCIA card 7 shown in FIG. As a result of the determination, if there is a contract, the descrambling key Ks in the program information is given to the descrambling unit 21 so that descrambling can be performed. 21 so that it cannot be viewed. If the result of this determination is that the viewing is OK, the scramble key Ks output from the viewability determining unit 24 in the PCMCIA card 7 is provided to the descramble unit 21.

In the following description, ECM is used in the same meaning as program information, and EMM is used in the same meaning as individual information. In digital broadcasting, program information and individual information are generally performed in an MPEG section format. Program information in the section format is called an ECM, and individual information is called an EMM.

In the pay broadcasting system and the pay broadcasting receiving apparatus described above, it is fundamental that the broadcasting station controls each receiving apparatus by sending an EMM. For example, in the case of viewing a pay-per-view program (hereinafter abbreviated as PPV program) by a prepaid system in which a prepayment is paid in advance and a fee for each program is subtracted from the prepayment balance, the supply of the EMM including the prepayment from the broadcasting station is also required. This is inconvenient because it has to be stored in the EMM decryption / storage unit 29 and removed every time the PPV program is viewed.

[0010] Information on the EMM and the advance payment must be provided for each broadcaster, and FIG. 8 also shows that a plurality of EMM decoding / storage units 29 including the storage of the advance payment are provided.

As a method of viewing PPV without receiving the advance payment by the EMM, a pay broadcasting system using a prepaid card can be considered. In that case E
A prepaid card must be provided for each broadcasting station (broadcasting company) as in the broadcast receiving the MM. This is similar to the situation where a bus card, a JR card, a telephone card, and the like cannot be integrated.

[0012]

When a prepaid card must be provided for each broadcasting station as described above, it is necessary to provide a plurality of card insertion holes in the receiving device, which increases the size of the pay broadcasting receiving device and the manufacturing cost. There was a problem that causes an increase. In addition, when a plurality of card insertion ports are not provided, a prepaid card must be replaced every time a broadcast station for PPV viewing is switched, and there is a problem in that the operation of the pay broadcast receiving apparatus is inconvenient. In view of the above problems, it is an object of the present invention to provide a more convenient pay-broadcast receiving method and apparatus using a prepaid card.

[0013]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a first apparatus and a second apparatus for managing the viewing of pay broadcasts.
The first device and the prepaid card containing prepaid information for viewing the pay broadcast in the pay broadcast receiving device connected to the second device directly or in the second
A method for receiving a broadcast broadcast in which the first device authenticates the prepaid card by a public key encryption method and in which there is no problem as a result of the authentication, the method includes: This is a pay-broadcast receiving method in which information is encrypted and given from the prepaid card to the first device.

According to the present invention, there is also provided a pay-broadcast receiving apparatus in which a first apparatus and a second apparatus for managing the viewing of pay-broadcasts are connected to each other. Directly with the card or the second
A communication unit that indirectly connects to the first device via the device, wherein the communication unit authenticates the prepaid card by the first device using a public key cryptosystem, and there is no problem with the authentication result. In this case, a pay broadcast receiving apparatus is characterized in that the prepaid money information is encrypted and given from the prepaid card to the first apparatus.

[0015] The present invention also provides a pay-broadcast receiving apparatus in which a first apparatus for performing viewing management is connected to a second apparatus.
A prepaid card containing prepaid money information for viewing pay broadcasts, which is directly or indirectly connected to and communicates with the first device via the second device,
A pay-broadcast receiving apparatus, which is characterized in that prepaid-payment information is encrypted by a secret key cryptosystem and given to the first apparatus from the prepaid card.

[0016]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a system configuration diagram showing a pay broadcast system to which a pay broadcast receiving apparatus according to the present invention is applied. As shown in FIG. 1, in the present invention, prepaid money information is transferred to a PCMCIA card using a prepaid card.

Referring to FIG. 1, pay broadcasting system 100
Is a pay broadcast receiving apparatus 1 and a satellite 15 for broadcast relay.
0, A broadcast station 101, and B broadcast station 102. The A broadcast station 101 and the B broadcast station 102 each include a content storage unit 111 and a scramble unit 1 for storing content that is broadcast content such as video, audio, and data.
12, a multiplexing unit 113, an ECM generation / encryption unit 114, a work key Kw memory 115, a prepaid card issuing unit 116 that manages the work key Kw and issues a prepaid card 15, and a transmission antenna 117.

The pay broadcast receiving apparatus 1 comprises an antenna 3, a tuner 5, a PCMCIA card 7, an MPEG decoder 9,
A system control microcomputer 11 and a modem 13 are provided.

The PCMCIA card 7 includes a descrambling unit 21, an ECM decrypting unit 22, a Kw / prepayment memory 23,
A viewing permission / inhibition determination unit 24, a viewing information memory 25, and a public key encryption communication authentication unit 26 are provided. Among the components of the PCMCIA card 7, the descrambling unit 21, the ECM decoding unit 22, the viewability determining unit 24, and the viewing information memory 25 are the same as the corresponding components of the conventional pay broadcast receiving apparatus shown in FIG. It has various functions.

The characteristic components of this embodiment are the Kw / prepayment memory 23 and the public key encryption communication authentication unit 26. The public key encryption communication authentication unit 26 includes the prepaid card 15 and the public key encryption. By performing communication, the work key Kw and the advance payment stored in the prepaid card 15 can be accepted into the Kw / prepayment memory 23.

In the example of FIG. 1, the EMM is sent and the information on the contract and the work key Kw are sent to the broadcasting station 101 and
I did not give it from 102. As an alternative to this, the prepaid card 15 and the work key K
w is stored, and the viewer who purchased w transfers the information in the prepaid card 15 to the PCMCIA card 7. The prepaid card 15 is a card with a built-in microcomputer called an IC card or a smart card. The PCMCIA card 7 has a prepaid card interface and an insertion port (not shown) so that the card can be inserted into the PCMCIA card 7 and used. .

If the prepaid card 15 is encrypted with the master key Kmi unique to the receiving device as in the conventional EMM, the card cannot be freely distributed and it is inconvenient. It shall be. For this reason, it is assumed that the PCMCIA card 7 has a public key encryption communication authentication unit 26, and the prepaid card 15 has a function of processing a similar public key encryption (not shown).

FIG. 2 shows a PCMCIA for transferring the advance payment information and the work key Kw using the public key encryption.
It shows an example of a communication sequence between the card 7 and the prepaid card 15.

Here, the PCMCIA card 7 has a public key Kp for encrypting an IC card as a communication partner.
And a secret key Kq for decrypting the encryption. The IC card as the prepaid card 15 has a public key Ki for encrypting the PCMCIA card 7 as a communication partner and a secret key Kj for decrypting the encryption by itself.

Next, the communication procedure will be described with reference to FIG. First, the IC card that is the prepaid card 15 is a PC
When inserted into the MCIA card 7, the IC card issues a prepaid card processing start request (step 1).
When the PCMCIA card returns a response of approval of the prepaid processing (step 2), the IC card provides its own public key Ki to the PCMCIA card and provides the PCMCIA with the PCMCIA card.
Request the public key of the card (step 3). On the other hand, the PCMCIA card answers its own public key Kp (s
step4).

Subsequently, the IC card sends an encrypted text Kp (predetermined data) obtained by encrypting predetermined data for a communication test using the public key Kp of the PCMCIA card (step 5).
The MCIA card decrypts the ciphertext Kp (predetermined data) with the private key Kq set with its own public key Kp, and determines whether the PCMCIA card contains the predetermined data for communication test which the PCMCIA card also has in advance. If it is determined that the communication is successful, that is, if the communicating IC card can be recognized as a card corresponding to a predetermined public key encryption algorithm and a reliable card having predetermined test data, the test is OK. Is given to the public key K of the IC card.
i and sends the ciphertext Ki (test OK) (st
ep6).

An IC that has received the ciphertext Ki (test OK)
The card decrypts with the private key Kj set with its own public key Ki, and determines whether or not data indicating the test OK is included. If it is included, the initial session between the PCMCIA card and the IC card is finished.

If there is a problem in the communication between step 5 and step 6, the initial session is abnormal and the subsequent processing is not performed. PCMCIA card and I
To omit C card authentication, use step 5 and step 5.
The communication of No. 6 is unnecessary.

Subsequently, the work key Kw is encrypted from the IC card with the public key Kp, and the ciphertext Kp (Kw) is sent (st
ep7). PCMCI receiving this ciphertext Kp (Kw)
The A card decrypts with its own secret key Kq, accepts it without a decryption error, stores it in the card, and encrypts the information of OK with the public key Ki and sends it (step)
8). Note that the work key Kw is not limited to one type,
A plurality of types to be changed in the future can be prepared in the IC card and given to the PCMCIA card.

Subsequently, the prepaid information is encrypted with the public key Kp from the IC card and sent to the PCMCIA card (st
ep9). The PCMCIA card which has received the prepayment information decrypts the encrypted prepayment with its own private key Kq, stores it in the card if it is accepted without a decryption error, and encrypts the information of OK with the public key Ki. I
Send to C card (step 10). After obtaining the information that the IC card is accepted, the prepaid money information in the IC card is deleted.

The timing of erasing the advance payment information on the IC card side may be changed as follows. That is, s
PCM with encrypted prepayment information from IC card in step 9
After transmitting to the CIA card and tentatively registering the prepayment information in the PCMCIA card, transmitting the encryption acceptance OK from the PCMCIA card to the IC card in step 10 and erasing the prepayment information on the IC card side receiving this. ,
The deletion completion may be notified from the IC card to the PCMCIA card (step 11), and the PCMCIA card that has received the deletion completion may be changed to formally register the prepayment information.

As shown in the communication sequence diagram of the modification of the first embodiment shown in FIG. 3, the PCMCIA card and the IMC
For the authentication of the C card, there is also an authentication method using the reversibility of public key encryption. This authentication method using public key cryptography takes advantage of the property of public key cryptography that the original data can be restored even if the order of encryption and decryption is reversed, and it is necessary to know the secret key that only the sender can know. Being able to confirm at the receiving end proves the identity of the transmitting end.

Steps 1 to 4 in FIG.
7 to 10 correspond to the corresponding steps in FIG.
Is the same as In step 5 in FIG. 3, after the predetermined data is encrypted with the private key Kj paired with the public key Ki, the data is encrypted with the public key Kp and the ciphertext Kp (Kj (predetermined data)) is sent.

The PCMCIA receiving the ciphertext Kp (Kj (predetermined data)) decrypts it with the private key Kq paired with the public key Kp and then encrypts it with the public key Ki of the IC card. Is obtained. By using this method, it is proved that the IC card has the secret key Kj that can be known only by the source of the predetermined data.

When the IC card is authenticated, the PC
The MCIA card encrypts the test OK message with its own secret key Kq, and sends an encrypted text Ki (Kq (test OK)) encrypted with the IC card public key Ki to the IC card (step 6). This ciphertext Ki (Kq (test O
On the IC card side receiving K)), the PCMCIA card can be similarly authenticated by the public key authentication method.

In the first embodiment and its modifications,
The above description has been made as an example in which all broadcasting stations assume the sale of programs using prepaid cards. On the other hand, in the pay broadcast system using the pay broadcast receiving apparatus according to the second embodiment of the present invention shown in FIG. 4, the broadcast station A sends the EMM and the broadcast station which manages the viewers, and the broadcast station B serves as the broadcast station. This is an embodiment in the case of a broadcasting station that sells programs using prepaid cards.

The difference between FIG. 1 and FIG. 1 is that the information transferred and stored in the PCMCIA card from the prepaid card is the work key Kw and the advance payment, whereas the PCMCIA card 7 in FIG. An EMM decryption / storage unit that stores the EMM information corresponding to the A broadcast station 103 as well as the work key Kw and the advance payment, which are data in the prepaid, from the prepaid as in the conventional example of FIG. 29.

In such a system, at the time of viewing, the broadcast station is controlled by a viewer such as the A broadcast station 103 or a prepaid card such as the B broadcast station 102, depending on the ECM sent from the broadcast station. The attribute data of the corresponding broadcasting station is sent, and the viewing permission / non-permission determining unit 24 of the pay broadcast receiving apparatus 1 performs the viewing management determination process using the EMM information for each broadcasting station, or the program viewing fee is calculated from the advance payment. It is determined whether or not the content is to be withdrawn and processed.

Alternatively, in a system in which a broadcast station that sends an EMM and manages the viewers can send the EMM information using the EMM and manage the viewer, the EMM information including the advance payment is stored in the prepaid card 15. If the EMM is sold and the viewer transfers the EMM to the PCMCIA card 7 and uses it, the EMM can be managed in the same row without using the attribute data of the ECM as described above.

In the embodiment described with reference to FIGS. 1 and 4, the public key cryptosystem has been described as a security source. However, even if the prepaid card is counterfeited even if it is a prepaid card that can process public key encryption, it is doubtful whether the card is really a reliable card. For this reason, certificates should be used as a method of strengthening the system. This example will be described with reference to FIG.

FIG. 5 is a block diagram showing a configuration of a pay broadcast system using a third embodiment of the pay broadcast receiving apparatus according to the present invention. In the pay broadcast system 300, the B broadcast station 102 sends a prepaid card certificate 3 using an ECM message to each pay broadcast receiver 1.
2 shall be sent. The certificate is, for example, information for each prepaid card 15. For example, the certificate for the B broadcast station 102 is broadcast by the B
It is assumed that the certificate 32 is stored in the CIA card 7 or selected at the B broadcast station 102 when the information of the prepaid card is transferred, and is used. Since the certificate 32 is meaningless information if forged, it must be protected by encryption.

In the example shown in FIG. 5, the certificate 32 is encrypted with the encryption key Kwp.
Here is an example in which is protected by encryption. The decryption key Kwp for decrypting the encryption certificate is obtained by a method previously incorporated in the Kwp memory 33 in the PCMCIA card 7 as shown in FIG. 5 or a work key Kw of an ECM encryption key (not shown).
Similarly, the encryption key Kwp may be given to each receiving device by EMM.

The above processing will be described with reference to the communication sequence diagram of FIG. Ste in the initialization session
Steps p1 to step6 are the same as those in FIG. In step 7 of the initialization session, the certificate is sent from the IC card to the PCMCIA card. PCMCI receiving this
The A card compares the certificate broadcast in the ECM message, determines whether the certificate sent from the IC card is correct, and if it can be accepted, returns OK in step 8. ste
The prepaid processing section after p9 is the
It is the same as that after p7.

The above embodiment has been described on the assumption that public key cryptography is used. Public key cryptography usable in these embodiments includes RSA cryptography, Rabin cryptography, elliptic cryptography, and the like. However, public key cryptography has the advantage of being able to perform cryptographic communication without knowing the other party's encryption key in advance, but generally requires a large amount of computation for encryption processing and decryption processing and takes a long processing time.

FIG. 7 is a block diagram showing a configuration of a pay broadcast system using a fourth embodiment of the pay broadcast receiving apparatus according to the present invention. As a fourth embodiment, an example using secret key encryption will be described.

Although not much different from FIG. 5, in FIG. 7, the secret key Kwp is used in the authentication processing of the prepaid card. For this reason, the Kwp memory 40 for storing the secret key Kwp in advance and the secret key
1 in advance in the PCMCIA card 7,
The IC card that is the prepaid card 15 also has the same secret key K
wp. Although not shown, EC
Similarly to the work key Kw of the M encryption key, the encryption key Kwp may be given to each receiving device by EMM.

[0047]

As described above, according to the present invention, the prepaid information for each broadcasting station is transmitted from the prepaid card to the PCM.
The transfer to the CIA card eliminates the need to provide a plurality of card insertion slots for prepaid cards for each broadcasting station in the pay broadcast receiving apparatus, and has the effect of simplifying the structure of the pay broadcast receiving apparatus and reducing its size.

Further, after the prepaid information is transferred, there is no need to insert the prepaid card into the pay broadcast receiving apparatus, which improves the operability and convenience, and also enables the pay broadcast receiving method and apparatus to transfer the prepaid information safely. Can be provided.

In the description of the invention, a PCMCIA card has been described as a card that is always inserted into the receiving device. However, this card is similar to a prepaid card.
It goes without saying that a similar effect can be obtained even with a C card (smart card).

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a pay broadcast system using a first embodiment of a pay broadcast receiving apparatus according to the present invention.

FIG. 2 shows a pay broadcast receiving apparatus and a prepaid card (IC) in a first embodiment of the pay broadcast receiving apparatus according to the present invention.
FIG. 4 is a communication sequence diagram with the card.

FIG. 3 is a communication sequence diagram in a modified example of the first embodiment.

FIG. 4 is a configuration diagram of a pay broadcasting system using a second embodiment of the pay broadcast receiving apparatus according to the present invention.

FIG. 5 is a configuration diagram of a pay broadcast system using a third embodiment of the pay broadcast receiving apparatus according to the present invention.

FIG. 6 is a communication sequence diagram in the third embodiment.

FIG. 7 is a configuration diagram of a pay broadcast system using a fourth embodiment of the pay broadcast receiving apparatus according to the present invention.

FIG. 8 is a configuration diagram of a pay broadcasting system using a conventional pay broadcast receiving apparatus.

[Explanation of symbols]

1 ... pay broadcasting receiver, 3 ... antenna, 5 ... tuner,
7 PCMCIA card, 9 MPEG decoder, 11
... System control microcomputer, 13 ... Modem, 15
... Prepaid card, 21 ... Descramble part, 22 ...
ECM decryption unit, 23: Kw / prepayment storage unit, 24: viewability determination unit, 25: viewing information memory, 26: public key encryption communication authentication unit, 100: pay broadcasting system, 101: A
Broadcasting station, 102 ... B broadcasting station, 111 ... Content storage unit, 112 ... Scramble unit, 113 ... Multiplexing unit, 114
... ECM generation / encryption unit, 115 ... Work key memory, 1
16: prepaid card issuing unit, 117: antenna, 1
50 ... Satellite.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H04L 9/00 H04L 9/00 9/08 601A

Claims (7)

[Claims] 1. A pay-broadcast receiving apparatus, in which a first apparatus and a second apparatus for managing viewing of a pay-broadcast are connected, including prepaid information for viewing the first apparatus and the pay-broadcast. A paid broadcast receiving method for directly or indirectly connecting and communicating with the prepared prepaid card via the second device, wherein the first device performs authentication of the prepaid card by a public key cryptosystem, and performs authentication. If there is no problem as a result, the prepaid money information is encrypted and given to the first device from the prepaid card. 2. A pay-broadcast receiving apparatus to which a first apparatus and a second apparatus for managing pay-broadcast viewing management are connected, wherein the pay-broadcast receiving apparatus directly includes a prepaid card containing prepaid-payment information for viewing the pay broadcast. Or a communication unit indirectly connected to the first device via the second device, wherein the communication unit authenticates the prepaid card by the first device using a public key cryptosystem, and performs authentication. If there is no problem as a result, the prepaid money information is encrypted and given from the prepaid card to the first device. 3. The second device fetches certification data of the prepaid card broadcasted from a broadcasting station, and fetches the prepaid information from the prepaid card to the first payment card.
And determining whether or not the prepaid card is accepted based on the certification data when receiving the prepaid card, and accepting the prepayment information from the prepaid card when judging that the prepaid card is acceptable. The pay-broadcast receiving device according to the above. 4. The proof data is encrypted from the broadcast station and broadcast as encrypted proof data, and the encrypted proof data is decrypted with a first encryption / decryption key possessed in advance, and the proof data is encrypted. 4. The pay-broadcast receiving apparatus according to claim 3, wherein the pay-broadcasting apparatus receives the broadcast. 5. The charge according to claim 4, wherein the first encryption / decryption key for decrypting the proof data is obtained by decryption using a second encryption / decryption key unique to the first device. Broadcast receiver. 6. A pay-broadcast receiving apparatus in which a first apparatus for performing viewing management is connected to a second apparatus, wherein the first apparatus is directly connected to a prepaid card containing prepayment information for viewing pay-broadcast or the second apparatus. A device for indirectly connecting to and communicating with the first device via a device, wherein the prepaid information is encrypted by a secret key cryptosystem and given to the first device from the prepaid card. Broadcast receiver. 7. A third encryption / decryption key for decrypting the prepaid fee, wherein the third encryption / decryption key encrypted and multiplexed with the broadcast is obtained by using a fourth encryption / decryption key unique to the first device. 7. The pay-broadcast receiving apparatus according to claim 6, wherein the pay-broadcast receiving apparatus is obtained by decoding.