JP6518487B2 - Delivery device, delivery system, delivery method, electronic device, broadcast device, and receiving program - Google Patents

Description

  The present invention relates to a distribution apparatus, a distribution system, a distribution method, and a broadcast apparatus that distributes an encrypted content signal, and an electronic apparatus and a reception program that receive the encrypted content signal.

  2. Description of the Related Art Conventionally, content signals are transmitted by broadcast waves, and received and reproduced by electronic devices such as televisions. In recent years, it has also become common for content signals to be transmitted by communication means and to be received and reproduced by electronic devices as well.

  The provider of these services encrypts and transmits the content signal so that only the contracted user can view the content. Therefore, it is necessary for the receiving electronic device to decrypt the encrypted content signal.

JP, 2010-178176, A

  In general, the encryption processing in the case of transmitting the content signal by the broadcast wave and the encryption processing in the case of transmitting the content signal by the communication means are different. Therefore, the electronic device needs both a functional unit for decrypting a content signal encrypted for broadcast waves and a functional unit for decrypting a content signal encrypted for communication means. . As a result, the configuration of the electronic device becomes complicated, and there is a problem that the manufacturing cost and the power consumption increase.

  The present invention has been made in view of the above problems, and an object thereof is to provide an electronic device and a receiving program capable of decrypting an encrypted content signal with a simple configuration. Another object of the present invention is to provide a distribution apparatus, a distribution system, a distribution method and a broadcasting apparatus for distributing encrypted content signals to such electronic devices.

According to an aspect of the present invention, there is provided a content delivery system including a broadcast device (1), a delivery device (2), and an electronic device (3), wherein the electronic device (3) is a unique one The broadcast apparatus (1) has a first key (Km) corresponding to the first key held by the electronic device, and a second key (Ks) corresponding to the first key. And the third key (Kw), and the broadcast device (1) uses the second key (Ks) to generate a content signal including control information necessary for content delivery by broadcast waves. And a first encryption unit (121) for generating an encrypted content signal, and using the third key (Kw), the second key (Ks) and the content signal. The first license information (ECM) is encrypted by encrypting the content information used to determine whether the decryption is permitted or not. Using the second encryption unit (122) for generating the second key and the fourth key (Km) to encrypt the contract information of the electronic device and the third key (Kw), and the second license A third encryption unit (123) for generating information (EMM), and a first transmission unit (124) for transmitting the encrypted content signal and the first license information (ECM) by broadcast wave And a second transmission unit (125) for transmitting the second license information (EMM) to the electronic device having the first key (Km) by the communication unit, and the distribution The device (2) comprises: a first receiving unit (21) for receiving the encrypted content signal and the first license information (ECM) from the broadcast device; and the first component in the encrypted content signal. At least control information And the compressed content signal after the replacement process is stored in the storage unit (23), and the first license information (ECM) is stored in the storage unit. It is determined based on the first license information whether or not to transmit the stored content signal to the electronic device in response to a request from the processing unit (22) and the electronic device, and it is determined to transmit And a distribution unit (24) that distributes the accumulated content signal and the first license information (ECM) to the electronic device by the communication unit, and the predetermined value has a high compression rate. Or the electronic device (3) broadcasts the encrypted content signal and the first license information (ECM) transmitted from the broadcasting device. , And a third receiving unit (31b) for receiving from the communication means the second license information (EMM) transmitted from the broadcasting apparatus; and the electronic device has A first decryption unit (321) for decrypting the second license information (EMM) using the first key (Km) and recovering the contract information and the third key (Kw); A second decryption unit (322) for decrypting the first license information (ECM) using the restored third key (Kw) and recovering the second key (Ks) and the content information And a contract determination unit (324) that determines whether or not to decrypt the encrypted content signal based on the content information and the contract information, and when it is determined that decryption is performed, the restored Use the second key (Ks) And a third decryption unit (33) for decrypting the encrypted content signal, and further requesting transmission of the content signal to the distribution device, and transmitting from the distribution device A communication unit (36) for receiving the encrypted content signal and the first license information from the communication unit, and the second decryption unit (322) comprises the second reception unit (31a) Decryption processing is performed on the first license information (ECM) received by the communication unit (ECM) and the first license information (ECM) received by the communication unit (36), and the contract determination unit 324) determines whether to decode the content signal received by the second receiving unit (31a) or the content signal received by the communication unit (36) And the third decoding unit (33) applies the content signal received by the second receiving unit (31a) and the content signal received by the communication unit (36). And a delivery system characterized by performing a decryption process.

  According to such a configuration, since the distribution device receives the encrypted content signal from the broadcast wave, the content signal encrypted for the broadcast wave can be distributed to the electronic device as it is. Further, the electronic device processes both the content signal received from the broadcast wave and the content signal received from the communication means, so that the configuration can be simplified.

According to one aspect of the present invention, a receiving unit for receiving an encrypted content signal and license information for decoding the same from a broadcast wave, and storing the received content signal and license information in a storage unit There is provided a distribution apparatus comprising: a processing unit; and a distribution unit configured to distribute stored content signals and license information by communication means in response to a request from the electronic device.
According to such a configuration, since the encrypted content signal is received from the broadcast wave, the content signal encrypted for the broadcast wave can be distributed to the electronic device as it is.

In addition, the encrypted content signal includes control information necessary for transmission by broadcast waves, and the processing unit replaces at least a part of the control information with a predetermined value from the encrypted content signal. The compressed content signal after the replacement process may be compressed. In this case, it is desirable that the predetermined value be a value for increasing the compression rate or 0.
According to such a configuration, the compression ratio can be increased by replacing the control information.

The distribution unit determines whether to transmit the requested content signal to the electronic device based on the license information in response to a request from the electronic device, and when it is determined to transmit. The content signal may be distributed.
According to such a configuration, it is possible to appropriately determine the electronic device to which the content signal should be distributed.

  Further, the processing unit corrects the license information and stores it in the storage unit, and the distribution unit corrects the license information whether to transmit the requested content signal to the electronic device. It may be determined based on

According to an aspect of the present invention, it is determined that a receiving unit that receives an encrypted content signal from a broadcast wave, a contract determining unit that determines whether or not the encrypted content signal is to be decrypted, and An electronic device is provided, further comprising: a decryption unit that decrypts the encrypted content signal, and a communication unit that receives the encrypted content signal from the communication unit. Then, the contract determination unit determines whether to decode the content signal received by the reception unit or the content signal received by the communication unit, and the decryption unit The decoding process is performed on the content signal received by the receiving unit and the content signal received by the communication unit.
According to such a configuration, since the content signal received from the broadcast wave and the content signal received from the communication unit are also processed, the configuration of the electronic device can be simplified.

  According to an aspect of the present invention, there is provided a distribution system including: a broadcast apparatus that transmits an encrypted content signal by a broadcast wave; the distribution apparatus; and the electronic device.

  According to one aspect of the present invention, the step of receiving an encrypted content signal and license information for decoding the same from a broadcast wave, and storing the received content signal and license information in a storage unit There is provided a delivery method comprising the steps of: delivering the stored content signal and license information by the communication means in response to a request from the electronic device.

  According to one aspect of the present invention, the steps of receiving an encrypted content signal from a broadcast wave, receiving an encrypted content signal from a communication means, and for the content signal received from the broadcast wave Even if the content signal received from the communication means is also determined, the step of determining whether or not to decrypt, and the step of decrypting the encrypted content signal if it is determined to be decrypted A receiving program to be executed by a computer is provided.

According to one aspect of the present invention, there is provided a broadcast distribution unit that transmits a first signal that configures a content signal by a broadcasting unit, and a communication distribution unit that distributes a second signal that configures the content signal by a communication unit. And the first signal and the second signal have a common format such that one decoding unit can decode the first signal and the second signal, and the first signal is transmitted in synchronization with the second signal. There is provided a broadcast apparatus characterized by
According to such a configuration, since the first signal and the second signal can be decoded by one decoding unit, the configuration of the device that receives these signals can be simplified.

The broadcast apparatus includes an encryption unit that encrypts the content signal, and a content separation unit that separates the encrypted content signal into the first signal and the second signal. desirable.
According to such a configuration, since the content signal is encrypted by one encryption unit, the first signal and the second signal can be in the same format.

According to an aspect of the present invention, there is provided a receiving unit for composing a content signal, the receiving unit receiving a first signal encrypted by an encrypting unit from a broadcasting means, and transmitted in synchronization with the first signal. A communication unit configured to receive the second signal encrypted by the encryption unit, the content combining unit configured to receive the second signal encrypted by the encryption unit; and a content combining unit combining the first signal and the second signal; An electronic apparatus is provided, comprising: a decryption unit capable of decrypting both the encrypted first signal, the encrypted second signal, and the combined signal.
According to such a configuration, since one decoding unit performs the first signal, the second signal, and the combined signal, the configuration of the electronic device can be simplified.

  Further, according to an aspect of the present invention, there is provided a distribution system including the broadcasting device and the electronic device.

  Further, according to an aspect of the present invention, there is provided a step of receiving a first signal encrypted by the encryption unit, which constitutes a content signal, from the broadcasting means, and transmitted in synchronization with the first signal. Receiving from the communication means a second signal encrypted by the encryption unit, which composes the content signal, combining the first signal and the second signal, and decrypting means A receiving program is provided that causes a computer to execute the steps of: decrypting any of the encrypted first signal, the encrypted second signal, and the combined signal.

  According to the present invention, an encrypted content signal can be decrypted with a simple configuration.

BRIEF DESCRIPTION OF THE DRAWINGS The figure which shows schematic structure of the content delivery system which concerns on the 1st Embodiment of this invention. The figure which illustrates the relationship between the "goods" and "content" for using a content delivery system. FIG. 2 is a block diagram showing an internal configuration of each device of FIG. 1; FIG. 6 is a view showing an example of the structure of customer information of each customer stored in a customer information storage unit 11; FIG. 2 is a block diagram showing a detailed configuration of a content protection processing unit 12; A diagram for explaining content information. Diagram for explaining contract information. The figure which shows an example of a process of the process part 22. FIG. The figure which shows another example of a process of the process part 22. FIG. FIG. 2 is a block diagram showing a detailed configuration of the electronic device 3; FIG. 7 is a sequence diagram showing an example of processing operation of the content delivery system. The block diagram which shows the internal structure of each apparatus in the content delivery system which is a comparative example of this invention. The figure which shows schematic structure of the content delivery system which concerns on 2nd Embodiment.

  Hereinafter, embodiments according to the present invention will be specifically described with reference to the drawings.

First Embodiment
FIG. 1 is a diagram showing a schematic configuration of a content distribution system according to a first embodiment of the present invention. The content distribution system includes the broadcasting device 1, the distribution device 2 and the electronic device 3. Although one electronic device 3 is depicted in the figure, a plurality of electronic devices 3 are usually included in the content distribution system. The broadcast device 1 transmits the encrypted content signal to the electronic device 3 by a broadcast wave. The distribution device 2 transmits the encrypted content signal to the electronic device 3 by the communication means.

  Here, the content signal is a news, a movie, a drama, a music program, etc., and there is no particular limitation. Moreover, although a normal content signal includes a video signal and an audio signal, the content signal may include only one of the video signal and the audio signal.

  Further, the content signal includes control information such as PSI (Program Specific Information: program specific information) and SI (Service Information: program arrangement information). PSI is information necessary to reproduce broadcast content. The SI is information on broadcast content, and includes information such as the title and content of the content. Such control information is information that is necessary when the content signal is transmitted from the broadcasting device 1 by a broadcast wave and received and reproduced by the electronic device 3. However, the control information is not necessarily required in the case where the content signal is distributed from the distribution device 2 by the communication means and reproduced by the electronic device 3.

  The broadcast device 1 is provided, for example, in a broadcast station, and encrypts and protects a content signal, and then transmits the content signal by a broadcast wave.

  The distribution device 2 receives the content signal from the broadcast wave transmitted from the broadcast device 1 and stores the content signal therein. Then, the distribution device 2 distributes the content signal requested by the user using the electronic device 3 to the electronic device 3 by the communication means.

  The electronic device 3 is a smartphone, a tablet terminal, a personal computer, a television, or the like, and is a receiver used by the user. The electronic device 3 receives the content signal from the broadcast wave transmitted from the broadcasting device 1. Thus, the electronic device 3 can reproduce the content currently being broadcast in real time. Hereinafter, for convenience, such a method of distributing and reproducing content by broadcast waves is referred to as a real time broadcast service. The broadcasting device 1 and the electronic device 3 are sufficient if only using the real time broadcasting service.

On the other hand, the electronic device 3 receives the content signal stored in the distribution device 2 from the communication means by making a request to the distribution device 2. Thereby, the electronic device 3 can reproduce the content desired by the user at a time desired by the user. Hereinafter, for convenience, such a delivery and reproduction method of contents by the communication means will be referred to as a VoD (Video on Demand) service. In order to use the VoD service, the broadcasting device 1, the distribution device 2 and the electronic device 3 are required.
The real time broadcast service and the VoD service may be provided by the same operator or may be provided by different operators.

  The present embodiment is a process for VoD service provided by the communication means with almost no change of each functional unit in the electronic device 3 designed for the purpose of using only the real-time broadcast service which is exclusively a broadcasting service. To be diverted to

  When using the real-time broadcast service and / or the VoD service in such a content delivery system, the user needs to contract with the provider of each service and purchase a product for viewing the content.

  FIG. 2 is a diagram illustrating the relationship between “merchandise” and “content” for using the content distribution system. A product is a unit purchased by the user using the electronic device 3, and one product is associated with one or more contents.

  For example, in the figure, the contents C1 to C3 belong to the product P1. Therefore, the user who has purchased the product P1 can view the content C1 to C3. Conversely, the user who wants to view all or any of the content C1 to C3 may purchase the product P1. The contents C1 to C3 may be related to one another such as the first to third of the drama, or may not be particularly related.

  Further, in the figure, the content C2 belongs to the product P1 and the product P2. Thus, one content may belong to a plurality of products. In this case, the user who wants to view the content C2 may purchase the product P1 or may purchase the product P2.

  Further, in the same figure, the product belonging to the product P3 is the same as the product belonging to the product P2. However, the product P2 is a product that can view the content C2 and C4 only with the real-time broadcast service, and the product P3 can be a product that can view the content C2 and C4 with the VoD service as well as the real-time broadcast service. Then, the product P3 may be set to be more expensive than the product P2.

  As described above, the product is set from various viewpoints such as the type and number of contents, the service to be supplied, the charge, and the viewable period. This increases the user's choices and improves the convenience.

Information on such a product is transmitted from the broadcasting device 1 to the electronic device 3 by a broadcast wave or communication means. Information on a product is displayed on the electronic device 3, and the user can use the electronic device 3 to purchase an arbitrary product. Information indicating which user purchased which item is recorded as customer information in the broadcast apparatus 1 (described later). Further, information indicating a purchased product is stored in the electronic device 3 as contract information (described later).
FIG. 3 is a block diagram showing an internal configuration of each device of FIG. The internal configuration will be described in the order of the broadcast device 1, the distribution device 2 and the electronic device 3.
The broadcast device 1 includes a customer information storage unit 11 and a content protection processing unit 12.

  FIG. 4 is a diagram showing an example of the structure of customer information for each customer stored in the customer information storage unit 11. As shown in FIG. The customer information is information on a contractor who has made a contract with the content distribution system. More specifically, the customer information includes an ID (contractor ID) specifying the contractor, a product purchased by each contractor (purchased product), and a key Km (master key, 1st) unique to each contractor. Key) in association with each other and stored. The contractor ID may be, for example, information unique to the electronic device 3 used by the user, or may be any user ID or the like. The key Km is given to each contractor. That is, each electronic device 3 has a unique key Km, and the broadcasting device 1 has keys Km (that is, a fourth key corresponding to the first key) which are different from one another by the number of subscribers.

  Returning to FIG. 3, the content protection processing unit 12 acquires content from the content provider. Then, the content protection processing unit 12 performs protection processing so that the content signal is not reproduced by a third party other than the contractor in the process of transmitting the content signal to the distribution device 2 or the electronic device 3. Also, the content protection processing unit 12 generates license information for decrypting the encrypted content signal, using the contract information and the predetermined key. Hereinafter, the content protection processing unit 12 will be described in more detail.

  FIG. 5 is a block diagram showing the detailed configuration of the content protection processing unit 12. The content protection processing unit 12 includes a scrambler (first encryption unit) 121, encryption units (second and third encryption units) 122 and 123, and transmission units 124 and 125. The content protection processing unit 12 may be configured by one device or may be configured by a plurality of devices. In addition, each unit in the content protection processing unit 12 may be entirely configured by hardware, or at least a part is realized by software when an internal processor executes a content protection processing program (not shown). May be

  The scrambler 121 scrambles the content signal using the key Ks (scramble key, second key). Thus, the content signal is encrypted and can not be decrypted without the key Ks. The key Ks is a key possessed by the content protection processing unit 12 and is not different for each transmission destination electronic device 3, and is not different for each content.

  The encryption unit 122 encrypts the key Ks and content information (described later) using the key Kw (work key, third key), and generates license information ECM (Entitlement Control Message, first license information). . Thus, the key Ks and the content information can not be decrypted without the key Kw. The key Kw is also a key possessed by the content protection processing unit 12 and is not different for each transmission destination electronic device 3 and is not different for each content.

  FIG. 6 is a diagram for explaining the content information. The content information is information provided for each content signal, and indicates to which product the content belongs. For example, in FIG. 6, the content information indicates that the content to be provided is “C2” and belongs to the products “P1”, “P2” and “P3” (see FIG. 2).

  Returning to FIG. 5, the transmitting unit 124 transmits the broadcast content by combining the encrypted content signal generated as described above and the license information ECM. The encrypted content signal and the license information ECM are provided by the broadcasting service, and the transmission destination is not specified.

  On the other hand, the encryption unit 123 generates license information EMM (Entitlement Management Message, second license information) to be transmitted to the specific electronic device 3. More specifically, the encryption unit 123 encrypts the key Kw and contract information (described later) using the key Km of the destination contractor to generate license information EMM. Thus, the key Kw and the contract information can not be decrypted without the key Km. By transmitting the license information EMM by the communication means, the broadcast band can be prevented from being compressed, and it can be easily confirmed that the license information EMM has been received by the specific electronic device 3. Then, the transmission unit 125 transmits the license information EMM to the specific electronic device 3 by the communication means.

  FIG. 7 is a diagram for explaining the contract information. The contract information is generated from the customer information stored in the customer information storage unit 11. The contract information indicates which product a particular contractor has purchased. For example, in FIG. 7, a contractor whose contractor ID is “U1” (hereinafter, also simply referred to as “contractor U1”) uses the electronic device 3 to use the electronic device 3 to select the products “P1”, “P5” and “P6”. Indicates purchase (see Figure 4). The contract information and the key Kw are encrypted using a key Km1 (FIG. 4) unique to the contractor U1 and transmitted as license information EMM to the electronic device 3 of the contractor U1. Then, the license information EMM is stored in the electronic device 3.

  Since the license information EMM does not include information on individual contents, it may not be transmitted in combination with each content signal. The license information EMM is transmitted from the broadcast device 1 to the electronic device 3 periodically (for example, once a month) or when there is a change in the contract information (for example, when the contractor purchases a new product). You may make it transmit.

  Thus, the broadcasting device 1 transmits the encrypted content signal and the license information ECM by a broadcast wave, and transmits the license information EMM by the communication means.

  Subsequently, returning to FIG. 3, the distribution device 2 will be described. The distribution device 2 receives the encrypted content signal from the broadcast wave transmitted from the broadcast device 1 and distributes this to the electronic device 3 by the communication means. The distribution apparatus 2 includes a receiving unit (first receiving unit) 21, a processing unit 22, an accumulation unit 23, a distribution unit 24, and a customer information storage unit 25. The distribution device 2 may be configured by one device or may be configured by a plurality of devices. In addition, each unit in the distribution apparatus 2 may be entirely configured by hardware, or at least a part may be realized by software when an internal processor executes a distribution program (not shown).

Furthermore, when the real-time broadcast service and the VoD service are provided by the same operator, etc., at least a part of the distribution apparatus 2 may be provided in the broadcast station or in the broadcast apparatus 1, or the customer information storage unit 25 At least a part may be shared with the distribution device 2.
The receiving unit 21 receives the encrypted content signal and the license information ECM from the broadcast wave transmitted from the broadcasting device 1.

  The processing unit 22 processes the encrypted content signal and license information ECM as necessary, and compresses the content signal. Then, the compressed content signal is stored in the storage unit 23.

  FIG. 8 is a diagram illustrating an example of processing of the processing unit 22 and illustrates processing of the content signal. As shown in the figure, the content signal is divided into packets (for example, 188 bytes) and transmitted. Each packet has data for content and control information such as PSI and SI. As described above, when the content signal is distributed by the communication means, the control information is unnecessary. Therefore, the processing unit 22 removes at least a part of the control information, and substitutes, for example, 0.

  By replacing unnecessary control information in this manner, the compression rate can be improved. Of course, it may be replaced by another value that can improve the compression rate as compared to the case where it is not replaced. Not only removal but also replacement processing, the format (shape) of the content signal such as the number of packets and the number of bits in the packets can be kept.

  FIG. 9 is a diagram showing another example of the process of the processing unit 22, and shows the process for the license information ECM. The license information ECM includes content information (for example, FIG. 6), and the processing unit 22 may correct this content information.

In FIG. 2, it has been described that the product P2 is a product capable of viewing the content C4 only by the real-time broadcast service, and the product P3 is a product capable of viewing the content C4 by the VoD service. In this case, the content information provided when transmitting the content signal for the content C4 from the broadcast device 1 indicates that the content C4 is included in the products P2 and P3. Then, the processing unit 22 deletes the product P2 as a product to which the content C4 belongs. Thereby, in the VoD service, it becomes possible to view and listen to the content C4 only with the product P3.
Of course, the processing unit 22 can arbitrarily change the license information ECM in consideration of various other circumstances.

The distribution device 2 can perform the process of correcting the license information ECM in this manner. Therefore, in the broadcasting apparatus 1, it is not necessary to generate content information for real-time broadcast service and content information for VoD service so that they can be distinguished, and even on the side of the receiving electronic device 3, content information for real-time broadcast service It is not necessary to be aware of whether it is content information for VoD service.
Returning to FIG. 3, after performing the above processing, the processing unit 22 stores the set of the compressed content signal and the license information ECM in the storage unit 23.

  The distribution unit 24 receives a request for content transmission from the electronic device 3. This request includes information for identifying the content signal and information indicating the contractor ID. Based on these pieces of information, the distribution unit 24 determines whether to distribute the requested content signal to the electronic device 3.

  More specifically, it is as follows. The distribution unit 24 specifies the product to which the requested content signal belongs, based on the content information (for example, FIG. 6, the corrected content information when corrected by the processing unit 22) included in the license information ECM. Further, the customer information storage unit 25 stores customer information (for example, FIG. 4) in the same manner as the customer information storage unit 11 of the broadcast apparatus 1. Therefore, the distribution unit 24 determines to distribute, if the specified product has been purchased by the contractor, based on the contractor ID.

  If it is determined that the distribution unit 24 does not distribute, that is, if the contractor has not purchased a product for viewing the requested content, the distribution unit 24 does not distribute the requested content signal to the electronic device 3. Even if the content signal is distributed to the electronic device 3, the content signal can not be reproduced by the contract determination of the electronic device 3 described later. Therefore, by not distributing the content signal from the distribution unit 24 to the electronic device 3, the load due to distribution can be reduced. In this case, information to the effect that delivery can not be performed because the item has not been purchased, or information for prompting the purchase of the item may be delivered to the electronic device 3.

  On the other hand, when the distribution unit 24 determines to distribute, the distribution unit 24 distributes the requested content signal to the electronic device 3 together with the license information ECM. The distribution unit 24 may decompress and distribute the compressed content signal, but may suppress the amount of communication by distributing the compressed content signal.

  Thus, the distribution device 2 distributes the content signal and the license information ECM to the electronic device 3 without performing protection processing specific to communication. Therefore, the content signal delivered to the electronic device 3 is only the unnecessary information removed from the content signal transmitted by the broadcasting device 1, and the format of the signal is essentially the same as the content signal transmitted by the broadcasting device 1 It is.

  Subsequently, the electronic device 3 will be described. The electronic device 3 includes a content protection cancellation unit 30 including a reception unit 31, a determination unit 32, and a dex rammer (third decoding unit) 33, a decoder 34, a reproduction unit 35, and a communication unit 36. The electronic device 3 may be configured by one device or may be configured by a plurality of devices. In addition, each part in the electronic device 3 may be entirely configured by hardware, or at least a part may be realized by software when an internal processor executes a reception program (not shown).

  The receiving unit 31 receives the encrypted content signal and license information ECM transmitted from the broadcasting device 1 from the broadcast wave, and receives the license information EMM transmitted from the broadcasting device 1 from the communication means.

  The determination unit 32 performs contract determination based on the license information ECM and EMM to determine whether to reproduce the received content signal, that is, whether to decrypt the encrypted content signal. If it is determined that reproduction is to be performed, the determination unit 32 decrypts the license information ECM and EMM using the key Km held by the electronic device 3. Thus, the key Ks is restored and supplied to the descrambler 33.

  The descrambler 33 decrypts the encrypted content signal determined to be reproduced using the key Ks, and restores the content signal before being encrypted. More specifically, the descrambler 33 descrambles the scrambled content signal.

  The decoder 34 converts the restored content signal into a video signal and / or an audio signal. The reproduction unit 35 is a display for reproducing a video signal or a speaker for reproducing an audio signal.

  If only using the real-time broadcast service, the electronic device 3 may be provided with the reception unit 31, the determination unit 32, the descrambler 33, the decoder 34, and the reproduction unit 35 described above. Furthermore, when using the VoD service, the function of the communication unit 36 may be added to the electronic device 3. The communication unit 36 is a functional unit that performs communication based on a general communication protocol, and when the electronic device 3 has such a function in advance, there is no need to add it in particular.

  The communication unit 36 requests the distribution device 2 to distribute the content signal according to the instruction of the user. Then, the encrypted content signal and the license information ECM distributed from the distribution device 2 are received from the communication means. Then, the communication unit 36 performs decompression processing when the content signal is compressed.

  The determination unit 32 described above can perform the contract determination both on the content signal transmitted from the broadcasting device 1 and on the content signal distributed from the distribution device 2. Similarly, the descrambler 33 can perform the descrambling process on the content signal transmitted from the broadcast device 1 and the content signal distributed from the distribution device 2. The reason is that there is no difference in format between the content signal and license information ECM transmitted from the broadcast device 1 and the content signal and license information ECM distributed from the distribution device 2.

Therefore, even when the VoD service is additionally used by using the electronic device 3 designed for the purpose of receiving the broadcast wave transmitted from the broadcasting device 1 and using the real-time broadcasting service, the receiving unit 31 determines These units can be diverted to the processing for VoD service with almost no change to the unit 32, the descrambler 33, the decoder 34 and the reproduction unit 35. In addition, the communication unit 36, which is newly required, may be coped with by upgrading the version of the electronic device 3 or the receiving program, as needed.
FIG. 10 is a block diagram showing the detailed configuration of the electronic device 3.

  The receiver 31 includes receivers (second receiver, third receiver) 31a and 31b. The receiving unit 31 a receives the encrypted content signal and the license information ECM from the broadcast wave transmitted by the broadcasting device 1. The receiving unit 31 b receives the license information EMM transmitted from the broadcasting device 1 from the communication unit. As apparent from the above description, the content signal and license information ECM received by the receiving unit 31a are the same as the content signal and license information ECM received by the receiving unit 21 of the distribution device 2. The communication unit 36 may receive the license information EMM and the content signal.

  The determination unit 32 includes decryption units (second decryption unit, third decryption unit) 321 and 322, a contract information storage unit 323, and a contract determination unit 324.

  The decryption unit 321 decrypts the license information EMM using the key Km held by the electronic device 3 to restore the key Kw and the contract information. The license information EMM generated by the content protection processing unit 12 of the broadcast apparatus 1 is transmitted to the specific electronic device 3 using the specific key Km. Since the electronic device 3 of the transmission destination has the same key Km, the license information EMM can be decrypted. The restored contract information is stored in the contract information storage unit 323.

  The decrypting unit 322 decrypts the license information ECM using the restored key Kw, and restores the key Ks and the content information. Here, the decryption unit 322 can perform the same decryption without being aware of whether the reception unit 31a is the license information ECM received from the broadcast wave or the communication unit 36 is the license information ECM received from the communication means. .

  The contract determination unit 324 determines whether to decode the received content signal based on the restored content information and the contract information. More specifically, the contract determination unit 324 specifies the product to which the received content signal belongs based on the content information (for example, FIG. 6). Furthermore, based on the contract information (for example, FIG. 7), the contract determining unit 324 determines that the specified product is to be decrypted if it is purchased by the contractor.

  When it is determined that decryption is to be performed, the contract determination unit 324 supplies the key Ks to the descrambler 33. If it is determined that decryption is not performed, the contract determination unit 324 does not supply the key Ks to the descrambler 33. In this case, information to the effect that delivery can not be performed because the item has not been purchased, or information for prompting the purchase of the item may be displayed on the reproduction unit 35.

  The descrambler 33 restores the encrypted content signal using the key Ks restored as described above. Here, the descrambler 33 can similarly decode without being aware of whether the receiving unit 31a is the content signal received from the broadcast wave or the communication unit 36 is the content signal received from the communication means. The restored content signal is converted into a video signal and an audio signal by the decoder 34, and the content is reproduced by the reproduction unit 35.

  FIG. 11 is a sequence diagram showing an example of the processing operation of the content distribution system. In the same figure, it is assumed that license information EMM including contract information is transmitted in advance from the broadcasting apparatus 1 to the electronic device 3 and contract information is stored in advance in the contract information storage unit 323.

  The content protection processing unit 12 of the broadcast device 1 performs protection processing on the content (step S11), and transmits the content signal and the license information ECM in a set by broadcast waves (step S12).

  The receiving unit 21 of the distribution device 2 receives the set of the content signal and the license information ECM from the broadcast wave (step S21). The processing unit 22 compresses the content signal after performing necessary processing on the content signal and the license information ECM (step S22), and stores the compressed content signal in the storage unit 23 (step S23).

  The electronic device 3 can receive the provision of the real time broadcast service by receiving the content signal and the license information ECM from the broadcast wave (step S31). That is, when viewing of the content to be broadcast is set by the user to the electronic device 3 (YES in step S32), the determination unit 32 decodes the content signal based on the license information EMM and the content information. It is determined whether or not to do (step S33).

If a contract is concluded between the user of the electronic device 3 and the real-time broadcast service provider, and a product for viewing the received content signal is purchased, it is determined to be decrypted (step YES in S33). Then, the descrambler 33 decodes the encrypted content signal, the decoder 34 converts the content signal into a video signal and / or an audio signal, and the reproduction unit 35 reproduces the content as a video signal and / or an audio signal ( Step S34).
On the other hand, the electronic device 3 can receive the provision of the VoD service by requesting the distribution device 2 to distribute the content signal (step S35).

  When receiving the content request (step S24), the distribution unit 24 of the distribution device 2 determines whether to distribute the content signal to the electronic device 3 that has transmitted the content request based on the license information ECM. If it is determined that distribution is to be performed (YES in step S25), the distribution unit 24 distributes the requested content signal and license information ECM to the electronic device 3 by the communication unit (step S26).

  The communication unit 36 of the electronic device 3 receives the set of the content signal and the license information ECM (step S36). Then, the determination unit 32 determines whether to decode the content signal based on the license information EMM and the content information (step S37). In general, the content determined to be distributed by the distribution unit 24 of the distribution device 2 should be determined by the determination unit 32 to be decrypted (YES in step S37). Then, in the same manner as step S34, the content is reproduced (step S38).

  FIG. 12 is a block diagram showing an internal configuration of each device in the content delivery system which is a comparative example of the present invention. In the comparative example, the distribution device 2 ′ does not receive the encrypted content signal and license information ECM from the broadcast wave, but directly acquires the content and stores it in the storage unit 23 ′. First, this point is largely different from FIG. 3 of the present embodiment.

  Then, in FIG. 12, when distributing the content signal from the distribution device 2 'to the electronic device 3', the content protection processing unit 51 provided in the distribution device 2 'performs content protection processing for distributing the content signal by the communication means Distribution to the communication unit 36 of the electronic device 3 '.

Generally, content protection processing for broadcast waves is different from content protection processing for communication means. Therefore, the content protection release unit 30 processing the content signal subjected to the content protection processing for broadcast and the license information ECM is diverted to process the content signal subjected to the content protection processing for communication means and the license information ECM. It is not possible. Therefore, the electronic apparatus 3 'is newly provided with a content protection cancellation unit 52 for canceling the content protection process for the communication means. As a result, it is necessary to provide the two content protection release units 30 and 52 in the electronic device 3 ', and the configuration of the electronic device 3 becomes complicated.
On the other hand, in the present embodiment shown in FIG. 3, one content protection release unit 30 may be provided in the electronic device 3, and the configuration of the electronic device 3 can be simplified.

  One of the advantages of this embodiment over the comparative example of FIG. 12 is the ease of adding a VoD service to an existing real-time broadcast service. For a business entity that newly performs VoD service, the distribution device 2 may be newly provided, and the broadcasting device 1 may be the same as that shown in FIG. For example, in the broadcast device 1, there is no need to change the protection processing for the content signal or the method of generating the license information ECM. Moreover, since the distribution device 2 receives the content signal protected by the broadcast device 1, the distribution device 2 does not have to perform protection processing on the content signal again. Also, for the user, the communication unit 36 may be added to each unit used for the real-time broadcast service, and there is no need to add the content protection cancellation unit.

Thus, in the first embodiment, the distribution device 2 receives the content signal and the license information ECM from the broadcast wave. Then, the distribution device 2 distributes the content signal and the license information ECM to the electronic device 3 by the communication means in the same format as transmission on the broadcast wave. Therefore, the content protection cancellation unit 30 of the electronic device 3 performs content protection processing for the content signal transmitted from the broadcasting device 1 by the broadcast wave and for the content signal distributed from the distribution device 2 by the communication unit. The configuration of the electronic device 3 can be simplified.
Although the example in which the license information EMM is transmitted by the communication unit is described in the present embodiment, the license information EMM may be transmitted by a broadcast wave.

Second Embodiment
In the VoD service in the first embodiment described above, content signals are stored, and distribution by the communication means is performed in response to a request from the electronic device. On the other hand, in the second embodiment described below, a part of the signal constituting the content signal is distributed by the broadcasting means and a part thereof by the communication means simultaneously in real time. Hereinafter, differences from the first embodiment will be mainly described.

  The content signal of the present embodiment is composed of a plurality of signals, and a part is distributed by the broadcasting means and another part is distributed by the communication means. By doing this, more information can be distributed as compared with the case of distribution using only the broadcast means or the communication means.

  For example, among the content signals, the main video signal (for example, the overhead video in a sports program) and the main audio signal may be broadcast means, an additional video signal (for example, a video focusing on a specific player in the sports program) and sub audio It may be distributed by As another example, of the content signals, the video signal of 4K resolution may be distributed by broadcast means, and additional information for making 4K resolution 8K resolution by hierarchical means using communication means. As another example, a video signal and an audio signal may be distributed by a broadcasting means, and related character information, image information, data and the like may be distributed by a communication means. It goes without saying that various other applications are conceivable.

  In any case, the plurality of signals constituting the content signal should be reproduced synchronously. Hereinafter, for convenience, among the signals constituting the content signal, the signal distributed by the broadcasting means is referred to as a broadcast distribution signal (first signal), and the signal distributed by the communication means is referred to as a communication distribution signal (second signal) . The broadcast distribution signal and the communication distribution signal may include a plurality of signals (for example, a Japanese audio signal and a Chinese audio signal).

  Each of the broadcast distribution signal and the communication distribution signal is composed of a plurality of packets. In each packet, for example, information indicating whether the packet is a packet distributed by the broadcast means or a packet distributed by the communication means is included in the header, for example. Each packet contains information indicating the timing at which it should be reproduced, such as an absolute time (presentation time) or a sequence number. Based on this information, the electronic device that has received the content signal can synchronize and reproduce the broadcast distribution signal and the communication distribution signal.

  FIG. 13 is a diagram showing a schematic configuration of a content delivery system according to the second embodiment. The content distribution system includes a broadcasting device 1a and an electronic device 3a.

  The broadcast device 1 a includes a content separation unit 13, a broadcast distribution unit 14, and a communication distribution unit 15 in addition to the units common to FIG. 3. The content separation unit 13 separates the encrypted content signal into a broadcast distribution signal and a communication distribution signal based on the information included in the signal forming the content signal. The broadcast distribution unit 14 transmits the broadcast distribution signal and the license information ECM, ECM by the broadcasting means. The communication distribution unit 15 transmits the communication distribution signal and the license information ECM by the communication means. The communication distribution unit 15 can efficiently transmit to unspecified destinations by transmitting them by multicast.

  Here, the content signal is encrypted with the key Ks in the scrambler 121 in the content protection processing unit 12 as described in FIG. Thus, the broadcast distribution signal and the communication distribution signal are both signals of the same format encrypted in the same manner by the key Ks. Further, the broadcast distribution signal and the communication distribution signal are not distributed in response to a request from the electronic device 3a, but both are distributed in real time in synchronization with each other at a specific time. Note that not all of the signals that constitute the content signal may be encrypted.

  The electronic device 3 a includes a content combining unit 37 in addition to the units common to FIG. 3. The content combining unit 37 is supplied with a broadcast distribution signal from the receiving unit 31 and a communication distribution signal from the communication unit 36. The broadcast distribution signal and the communication distribution signal may have delay differences because the distribution paths are different from each other. For example, a broadcast delivery signal may be received first, and a communication delivery signal may be received first. Therefore, the content combining unit synchronizes and combines the broadcast distribution signal and the communication distribution signal based on the information indicating the timing included in the broadcast distribution signal and the communication distribution signal.

  The content protection cancellation unit 30 is supplied with the license information ECM from the reception unit 31 and the communication unit 36, and the signal combined from the content combination unit 37 is a broadcast distribution signal from the reception unit 31, and the communication unit 36 communicates. Delivery signals are provided respectively.

  The determination unit 32 in the content protection cancellation unit 30 determines whether to decode the content signal based on the license information ECM. More specifically, based on the license information ECM received from the reception unit 31, the determination unit 32 determines whether to decode the broadcast distribution signal. Further, based on the license information ECM received from the communication unit 36, the determination unit 32 determines whether to decode the communication distribution signal. Further, based on the license information ECM received from the reception unit 31 and the license information ECM received from the communication unit 36, the determination unit 32 determines whether to decode the combined signal.

  The descrambler 33 in the content protection cancellation unit 30 is supplied with the signal combined from the content combination unit 37, the broadcast distribution signal from the reception unit 31, and the communication distribution signal from the communication unit 36, respectively. The descrambler 33 descrambles (decodes) any signal in response to a request from the user. More precisely, the descrambler 33 descrambles the elements (signals) of the content requiring descrambling with the program signal designated by the user's intention. As a result, the scrambled content signal is restored as a signal before being scrambled.

  Since the combined signal, the broadcast distribution signal and the communication distribution signal are all signals having a common format, which are similarly encrypted by the content protection processing unit 12 of the broadcast apparatus 1a, the descrambler 33 uses any of the signals. Even if there is, it can be descrambled. That is, it is not necessary to provide a descrambler for each of the combined signal, the broadcast distribution signal, and the communication distribution signal, and one descrambler 33 can be shared to descramble each signal.

The decoder 34 converts the restored signal into a video signal and an audio signal. At this time, the decoder may perform necessary processing as well. In the example described above, when the broadcast distribution signal is a 4K resolution video signal and the communication distribution signal is additional information, the decoder 34 generates an 8K resolution video signal from both signals. Also, if there are multiple audio signals, the decoder 34 may select one of them. Alternatively, when there is a main video signal and a sub video signal, the decoder may superimpose the sub video signal on a part of the main video signal.
The obtained video signal and audio signal are reproduced by the reproduction unit 35.

  As described above, in the second embodiment, the content signal encrypted by the content protection processing unit 12 of the broadcast device 1a is separated into the broadcast distribution signal and the communication distribution signal, and these are distributed in real time. Since the broadcast distribution signal and the communication distribution signal are similarly encrypted and the format is common, the electronic device 3a as a receiver can decode any signal with one descrambler 33, and the configuration of the electronic device 3 is simplified. it can.

  In the present embodiment, free broadcasts, that is, content signals that can be viewed without a special contract may be transmitted. In that case, the customer information storage unit 11 in the broadcast device 1a may not be present. The free broadcast may be grasped based on, for example, the control information ECM attached to the content signal. Then, the determination unit 32 in the electronic device 3a that has received such control information ECM may determine to always reproduce and output the key Ks to the descrambler 33.

  At least a part of the content distribution system described in the above-described embodiment may be configured by hardware or software. When configured with software, a program for realizing at least a part of the function of the content distribution system may be stored in a recording medium such as a flexible disk or a CD-ROM, and read by a computer for execution. The recording medium is not limited to a removable medium such as a magnetic disk or an optical disk, and may be a fixed recording medium such as a hard disk drive or a memory.

  Furthermore, a program for realizing at least a part of the function of the content distribution system may be distributed via a communication line (including wireless communication) such as the Internet. Furthermore, the program may be encrypted, modulated, compressed, or stored in a recording medium via a wired line or a wireless line such as the Internet or may be distributed.

  Although one skilled in the art may conceive of additional effects and various modifications of the present invention based on the above description, aspects of the present invention should not be limited to the individual embodiments described above. Absent. Various additions, modifications and partial deletions can be made without departing from the conceptual idea and spirit of the present invention derived from the contents defined in the claims and the equivalents thereof.

DESCRIPTION OF SYMBOLS 1 broadcast apparatus 11 customer information storage unit 12 content protection processing unit 121 scrambler 122, 123 encryption unit 124, 125 transmission unit 13 content separation unit 14 broadcast distribution unit 15 communication distribution unit 2 distribution device 21 reception unit 22 processing unit 23 accumulation Unit 24 Distribution unit 25 Customer information storage unit 3 Electronic device 30 Content protection release unit 31, 31a, 31b Reception unit 32 Determination unit 321, 322 Decoding unit 323 Contract information storage unit 324 Contract determination unit 33 Descrambler 34 Decoder 35 Reproduction unit 36 Communication unit 37 Content combination unit

Claims (6)

A content delivery system including a broadcasting device, a delivery device, and an electronic device, comprising:
The electronic device has a unique first key,
The broadcasting device has a fourth key corresponding to the first key held by the electronic device, a second key, and a third key.
The broadcast device is
A first encryption unit that encrypts a content signal including control information necessary for content distribution by broadcast waves using the second key, and generates an encrypted content signal;
A second encryption unit that encrypts the second key and content information used to determine whether the content signal can be decrypted using the third key and generates first license information; ,
A third encryption unit that encrypts contract information of the electronic device and the third key using the fourth key and generates second license information;
A first transmission unit for transmitting the encrypted content signal and the first license information by a broadcast wave;
A second transmission unit that transmits the second license information to the electronic device having the first key by the communication unit;
The delivery device is
A first receiving unit that receives the encrypted content signal and the first license information from the broadcasting device;
At least a part of the control information in the encrypted content signal is replaced with 0, and the encrypted content signal after replacement processing is compressed and stored in a storage unit, and the first license information is stored. A processing unit that stores the
It is determined based on the first license information whether or not to transmit the stored content signal to the electronic device in response to a request from the electronic device, and it is determined that the transmission is performed, A distribution unit that distributes the content signal and the first license information to the electronic device by communication means;
The electronic device is
A second receiving unit that receives the encrypted content signal and the first license information transmitted from the broadcasting device from a broadcast wave;
A third receiving unit that receives the second license information transmitted from the broadcasting device from a communication unit;
A first decryption unit that decrypts the second license information using the first key held by the electronic device and restores the contract information and the third key;
A second decryption unit that decrypts the first license information using the recovered third key to recover the second key and the content information;
A contract determination unit that determines whether to decrypt the encrypted content signal based on the content information and the contract information;
And a third decryption unit that decrypts the encrypted content signal using the recovered second key when it is determined that decryption is to be performed.
And a communication unit that requests the distribution device to transmit a content signal and receives the encrypted content signal and the first license information transmitted from the distribution device from a communication unit.
The second decryption unit decrypts the first license information received by the second reception unit as well as the first license information received by the communication unit.
The contract determining unit determines whether to decode the content signal received by the second receiving unit or the content signal received by the communication unit.
The distribution system, wherein the third decoding unit performs the decoding process on the content signal received by the second receiving unit and the content signal received by the communication unit. . A receiving unit that receives an encrypted content signal and license information for decoding the signal from a broadcast wave;
A processing unit that stores the received content signal and the license information in a storage unit;
And a distribution unit that distributes the accumulated content signal and the license information by a communication unit in response to a request from an electronic device.
The encrypted content signal includes control information necessary for transmission by broadcast waves,
The processing unit replaces at least a part of the control information with 0 from the encrypted content signal, compresses the encrypted content signal after replacement processing, and stores the compressed content signal in the storage unit. Characteristic distribution device.   The distribution unit determines whether or not to transmit the requested content signal to the electronic device in response to a request from the electronic device based on the license information, and when it is determined to transmit, the content The delivery device according to claim 2, wherein the signal is delivered. The processing unit corrects the license information and stores it in the storage unit.
The distribution apparatus according to claim 3, wherein the distribution unit determines whether to transmit the requested content signal to the electronic device based on the corrected license information. A broadcast apparatus for transmitting an encrypted content signal by a broadcast wave;
A distribution device according to any one of claims 2 to 4,
Only it contains an electronic device, and electronic equipment,
A second receiving unit that receives the encrypted content signal from the broadcast wave;
A contract determination unit that determines whether to decrypt the encrypted content signal;
And a decryption unit that decrypts the encrypted content signal when it is determined that decryption is to be performed.
A communication unit for receiving the encrypted content signal from the communication unit;
The contract determination unit determines whether to decode the content signal received by the reception unit or the content signal received by the communication unit.
The delivery system , wherein the decryption unit performs decryption processing on the content signal received by the reception unit and also on the content signal received by the communication unit . Receiving from the broadcast wave an encrypted content signal and license information for decrypting the signal;
Storing the received content signal and the license information in a storage unit;
Delivering the accumulated content signal and the license information by communication means in response to a request from an electronic device.
The encrypted content signal includes control information necessary for transmission by broadcast waves,
In the storing step, at least a part of the control information is replaced with 0 from the encrypted content signal, and the encrypted content signal after replacement processing is compressed and stored in the storage unit. Delivery method characterized by