JP5149233B2 - Content recording device - Google Patents

Description

  The present invention relates to a content recording apparatus that records content such as a program such as a television broadcast and can simultaneously distribute the recorded content.

  Currently, large-capacity content recording apparatuses capable of recording content centered on broadcast programs are used. Some of such content recording apparatuses are connected to a network and can exchange contents with other external devices.

  FIG. 8 shows a recorder with a built-in hard disk that handles encrypted content transmitted and received on a network that is currently in practical use (however, the recording medium is not only a hard disk but also a DVD or Blu-ray (registered trademark)). It is also possible to include an apparatus for recording on an optical recording medium such as the above.) FIG. The hard disk recorder shown in FIG. 8 includes an antenna 101, a tuner 103, an in-device encryption unit 105, a recording unit 107, an in-device decryption unit 111, a network encryption unit 115, and devices connected thereto. (1) 117a, equipment (2) 117b,.

  In a conventional device, when content received from a tuner or a network is recorded in a content recording unit, the content is recorded as it is, or each manufacturer performs its own encryption. When a content request from an external device is received, the external device determination unit determines the function of the requested external device, and the external device authentication unit authenticates whether the external device can output the content. Information on whether or not the device may be output may be obtained from outside via a broadcast wave or a network. When device authentication is successfully completed, the original encrypted content stored in the content recording unit is uniquely decrypted and returned to normal content, and then encrypted by the network encryption unit that performs encryption for the home network. Is output. Therefore, when there are transmission requests from a plurality of devices at the same time, in order to distribute the content to all the devices, network encryption units corresponding to the number of devices are used according to the capability of the network encryption unit for encrypting the content. Was sometimes necessary.

  Usually, the encryption unit, the decryption unit, and the external device authentication unit are often configured as one LSI as a set, and a plurality of LSIs are required to support multiple devices. As the number of external devices increases, the number increases, which increases costs.

  For example, in the video program viewing apparatus described in Patent Document 1 below, a tuner module, a network interface, means for locally encrypting program data, and locally encrypted program data are recorded and transmitted over a network. Means. Thereby, for example, a program can be recorded and the program can be viewed based on this, and the viewed program can be transmitted to the outside via the network (see FIG. 13).

JP 2006-279433 A

  However, in the conventional content recording apparatus as shown in FIG. 13, when different contents are simultaneously distributed to a plurality of external devices 117 connected to the home network, a common key determined in advance to be used between the devices is used. Or a device that encrypts content using an encryption key generated using a public key and a private key, and that is required depending on the capability of the network encryption unit that encrypts the content There is a problem that network encryption units 151b, 151d,. When the number of external devices increases, a very large number of network encryption units 115 are required, resulting in a significant increase in cost. That is, in practice, in the case of a content recording apparatus having only one network encryption unit, different contents may not be distributed simultaneously.

  In addition, in the case of the content recording device described in Patent Document 1, the content is recorded from a plurality of external devices, although it has a configuration for recording network (encoded as local in the prior art) encrypted program data. There was no disclosure regarding the mechanism for simultaneous delivery of.

  An object of this invention is to provide the apparatus which can respond to the simultaneous delivery of the different content from several external apparatuses.

  The content recording device according to the present invention is provided with a network encryption unit in front of the content recording unit, and when the content is requested from an external device connected to the home network, the device responds to the device that requested the content. After the external device authentication unit performs device authentication to investigate whether the content can be output, the network encrypted content and its decryption key are output in advance, and the multiple output control unit outputs the content to each device. Output control is performed. This makes it possible to realize a content recording apparatus that easily distributes different contents simultaneously to a plurality of external devices.

  In the conventional content recording apparatus, the network encryption unit is used when outputting the content stored in the internal storage unit. Therefore, when performing a plurality of outputs at the same time, the capability of the network encryption unit Depending on the situation, a plurality of network encryption means are necessary. However, as described in the prior art, by performing network encryption when recording from the tuner to the storage means, one network encryption means can be used. I made it.

  In addition, the prior art does not show a method for simultaneously outputting encrypted contents to a plurality of devices, and the operation load information obtained from each control unit inside the device for differentiation and the network transmission / reception unit A multiple output control processing unit has been added to control multiple simultaneous outputs to each device based on the network load status outside the device.

  Further, the multiple output control processing unit has a function of limiting the output target of the encrypted content based on information obtained from the encrypted content information processing unit, and can limit the viewing target device and the viewing target user. .

  A common key that is pre-determined to be used between devices, with the network encryption unit provided before recording in the content recording unit, and the external device authentication unit performing device authentication for each device connected to the network Or a means for encrypting content using an encryption key generated using a public key and a private key, and recording the content received by the tuner in the content recording unit in a network encrypted state, The decryption key associated with the content is stored in the content decryption key storage unit.

  When the content is requested from an external device connected to the authenticated network registered in the list managed by the external device authentication unit, the operation load information obtained from each control unit inside the device by the multiple output control unit Based on the network load status obtained from the network transmission / reception unit and the network, multiple simultaneous output control to each device is performed, and the decryption key corresponding to the network-encrypted content (encrypted so that it cannot be easily analyzed) Output to the device that requested the content, so that the encrypted content stored in the content recording unit in advance can be easily changed to a plurality of external devices without performing encryption processing when the content is output. A content recording apparatus that simultaneously distributes content can be realized.

  According to an aspect of the present invention, a content acquisition unit that acquires content, a content recording unit that records the acquired content, and the content recorded in the content recording unit are transmitted to a plurality of external devices via a network. And a network transmission / reception unit that encrypts the content recording unit by providing an encryption unit for encrypting the content between the content acquisition unit and the content recording unit. In addition to recording content, when content is requested from any of a plurality of external devices network-connected to the content recording device, the content recording is performed for each requesting external device after performing device authentication of the device. Multiple outputs to control transmission of encrypted content recorded in Content recording apparatus characterized by having a control unit is provided. As a result, a content recording apparatus that simultaneously distributes different contents to a plurality of external devices can be realized. In the conventional content recording apparatus, the network encryption unit is used when outputting the content stored in the internal storage unit. Therefore, when a plurality of outputs are performed simultaneously, a plurality of network encryption units are used. However, as described in the prior art, by performing network encryption during recording from the tuner to the storage means, the number of simultaneous recordings using one or a plurality of tuners can be accommodated. The apparatus is simplified by using network encryption means.

  A content decryption key storage unit that stores a decryption key created according to the encryption process in the encryption unit in association with the encrypted content, and the plurality of output control units are content corresponding to the encrypted content It is preferable that the decryption key is paired and transmitted to the requesting external device.

Further, the present invention can be used as follows as a copyright management system having a mechanism in which an encryption key / decryption key is different for each device.
1) Counting and accumulating content used from external devices, specifying the most frequently used external device, or designating which external device the user views the content when recording The content is recorded in the content recording unit after being encrypted with an encryption key suitable for only the external device selected by the user operation means. Then, only when the content list is requested from the device, the encrypted content information is inserted into the content list information so that the content can be selected only from the device. Even if the content can be selected, the content cannot be viewed if there is no decryption key corresponding to the external device. Thereby, it is possible to limit the external devices that can view the content.

2) The content is set to be viewable only by a specific user by an operation such as setting a password for viewing the content, for example, by a user operation, and an encryption key suitable for the external device used by the user is used. It is encrypted and recorded in the content recording unit. The encrypted content information is inserted into the content list information only when the content list is requested from the external device and a password suitable for the user viewing the content is received, so that the content can be viewed only from the external device. Configure. Thereby, it is possible to limit the users who can view the content.

3) The same content is stored by counting the content usage results, and is temporarily encrypted by means of specifying the external device with the highest use frequency, or with the encryption key of the external device selected and selected by the user during recording Thereafter, when the network encryption unit is not used, an encrypted content encrypted with an encryption key of another device is created, and a plurality of the same content encrypted with a plurality of encryption keys is stored. This makes it possible to implement a content recording apparatus that simultaneously distributes content to a plurality of external devices together with a decryption key corresponding to each device.

That is, according to another aspect of the present invention, the plurality of external devices are configured to be able to set an encryption key / decryption key for each device, and the external device determination unit uses the content from the external device. The content is encrypted with an encryption key that is suitable only for the accumulated external device with a high usage record or the external device selected by the designation of the external device that records the content received by the user operation input receiver. When the content list is requested from the external device, the content information is transmitted to the content list information to the external device, and the content is requested by the user's selection process from the external device. The decryption key corresponding to the encrypted content is preferably transmitted to the external device.
Even in a network using a copyright management system having a different mechanism, it is possible to limit devices that can view content by configuring the content to be viewable only from the device.

  The network encryption unit encrypts content for which a password has been set by a user with an encryption key suitable for a connected external device, requests a content list from the external device, and conforms to the content It is preferable that the decryption key corresponding to the encrypted content is transmitted to the external device only in the case of receiving the password in the content list information.

  For example, by performing a work such as setting a password for viewing the content by a user operation, and only the user can view the content, the content and the user are associated with each other.

  By configuring so that the content can be viewed only from the external device for which the user has entered the correct password, it is possible to limit the users who can view the content.

  Also, the same content is once encrypted by means of counting the content usage results and identifying external devices with high accumulated usage results or with the encryption key of the external device selected and selected by the user during recording Later, during a period when the encryption unit is not used, an encrypted content encrypted with an encryption key of another external device is created, and the same content encrypted with a plurality of encryption keys is stored in the encrypted content recording unit It is also possible to store a plurality of files.

  Thereby, encryption can be performed efficiently by executing encryption of external devices in series. Further, it is possible to realize a content recording apparatus that simultaneously distributes different contents to a plurality of external devices.

  The multiple output control unit includes a network management unit that detects a load on the network via the network transmission / reception unit. Based on the network load information from the network management unit, the plurality of output control units It is preferable to manage the above load. As a result, transaction management that enables smooth transmission of content between the external devices is performed, and output control of content is managed according to the network load status, so that different content can be smoothly transferred to a plurality of external devices. It can support simultaneous delivery.

  Further, it is preferable that the multiple output control unit determines whether or not content can be transmitted to the external device based on information from an external device determination unit having a device list of the external device connected via a network. . Furthermore, it is preferable that the content stored in the encrypted content recording unit is reproduced internally or transmitted to an external device.

  The content recorded in the encrypted content recording unit may have a re-encryption function for generating another encryption key again and re-encrypting after a certain period of time. If the content is always in the same encrypted state and the decryption key is the same, it cannot be said that there is no possibility of breaking the encryption. Therefore, there may be a function of generating another key again and performing encryption again after a certain period of time. When performing re-encryption, the content is not being used from the outside, but not when the content being input from outside is being encrypted or decrypted, but at a timing when the load on the device is low You may do it. Instead of re-encrypting the content at once, the content may be partially re-encrypted little by little at a fixed timing.

  According to another aspect of the present invention, a content acquisition unit that acquires content, a content recording unit that records the acquired content, and a content recorded in the content recording unit to a plurality of external devices via a network In a content recording apparatus having a network transmission / reception unit for transmission, an encryption unit encrypted by the content recording unit by providing an encryption unit for encrypting the content between the content acquisition unit and the content recording unit And an integrated control unit that centrally manages information of the entire device and a plurality of output control units that control a plurality of outputs, and the integrated management unit receives the self-device and the control unit from each control unit. Receives load information on the network and determines whether content can be output to the outside according to the load information It has ability, based on the determination, to the multiple-output control unit, the content recording device is provided, which comprises instructing whether to output the content. When the integrated control unit is requested for content from any of a plurality of external devices connected to the content recording device over the network, it receives, for example, information regarding whether external input is being performed or internal playback is being performed as load information of the own device. Then, it is determined whether or not the content can be output to the outside according to the load inside the device, and the multiple output control unit is instructed whether or not the content can be output to the external device. Based on this instruction, the multiple output control unit outputs or does not output the content. That is, in an apparatus that does not include the integrated control unit, the multiple output control unit has a function of determining the load on the device and on the network. On the other hand, the integrated control unit that centrally manages the information of the entire device determines the load inside the device and on the network, and instructs the multiple output control unit whether to output according to the state.

  After installing the network encryption unit in the stage before recording in the content recording unit, and when the content is requested from an external device connected to the home network, after the device authentication of the device requested by the external device authentication unit A content recording apparatus that simultaneously distributes different contents to a plurality of external devices can be realized by outputting network-encrypted content and its decryption key and performing output control to each device by a plurality of output control units. In addition, a plurality of simultaneous outputs can be controlled.

  According to the present invention, in a recording device that also serves as a content server that can simultaneously broadcast and record content to a plurality of external devices connected to a home network, content from a content recording unit to a plurality of external devices Content encryption / decryption is not required during transmission / reception. Further, it is not necessary to provide as many network encryption units and decryption units as the number of external devices to be output, the number of components can be reduced, and the cost and simplification of the devices can be achieved.

  Furthermore, in a network where the encryption key / decryption key is different for each device, by restricting the devices that view encrypted content or by restricting users, it is possible to determine the device and age that the user uses to view the content. It becomes possible to manage by user designation.

It is a functional block diagram which shows the example of 1 structure of the content recording device by the 1st Embodiment of this invention. It is a flowchart figure which shows the flow of the process at the time of the internal recording of a content. It is a flowchart figure which shows the flow of the process which performs network encryption at the time of video recording, and preserve | saves the information of an object apparatus. It is a flowchart figure which shows the flow of a process at the time of content reproduction inside. It is a flowchart figure which shows the flow of a process at the time of the output to the external apparatus of a content. It is a flowchart figure which shows the flow of the process at the time of re-encryption. FIG. 6A is a diagram illustrating an example of a device list of an external device according to the present embodiment, and FIG. 6B is an example of a device list of an external device having a device authentication result according to the present embodiment. FIG. It is a functional block diagram which shows the example of 1 structure of the content recording device by the 2nd Embodiment of this invention. It is a functional block diagram which shows the example of 1 structure of the hard-disk recorder which handles the encryption content transmitted / received on the network currently utilized now. It is a flowchart figure which shows the flow of a process at the time of the content request | requirement from the external apparatus of the connection object by the 3rd to 5th embodiment of this invention, and is a figure corresponding to FIG. 4 of 1st Embodiment. . It is a flowchart figure which shows the flow of a process at the time of the encryption content production corresponding to a different encryption key. It is a figure which shows an example of the management information of the encryption content information management part 31 of FIG. It is a figure which shows one structural example of the management information in the content decryption key management part 37a of FIG. 1 is a diagram illustrating a configuration example of a video program viewing device described in Patent Literature 1. FIG.

  In the present specification, the “content list” is a list of contents stored in the content recording unit, and the content name, recording date and time, which channel was broadcast, in which recording format, It has information such as. It is information associated with the content, not the content itself.

  A content recording apparatus according to an embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a functional block diagram showing a configuration example of a content recording apparatus according to the first embodiment of the present invention. A content recording apparatus A shown in FIG. 1 includes an antenna 1, a tuner 3, a broadcast encryption / decryption unit 5 that decrypts the encryption of a broadcast program, a partialization unit 7 that temporarily releases the MPEG-2 transport stream, A network encryption / decryption unit 11 having a network encryption unit 11a and a network decryption unit 11b, a reproduction output unit 15, a display device 17 for displaying reproduction output (may be externally attached), and encryption in the previous stage And an encrypted content recording unit 41 that records the recorded content. Furthermore, an internal recording setting unit 21, an internal recording control unit 23, an internal playback control unit 25, and an internal playback setting unit 27 are provided for performing internal processing. The program encrypted by the network encryption unit 11a is recorded in the encrypted content recording unit 41 (HDD) via the internal recording control unit 23. The recorded encrypted content is managed by the encrypted content information management unit 31.

  The content decryption key for decrypting the content encrypted by the network encryption / decryption unit 11 is stored in the content decryption key storage unit 37b and managed by the content decryption key management unit 37a.

  The network encryption unit 11a is provided in front of the encrypted content recording unit 41 for recording content, and the external device authentication unit 55b performs device authentication for each external device 61 connected to the network. Means are provided for encrypting the content using a common key that is determined in advance or using an encryption key generated using a public key and a secret key. The content received by the tuner is recorded in the encrypted content recording unit 41 in a network-encrypted state, and the decryption key associated with the encrypted content is stored in the content decryption key storage unit 37b.

  A user operation by the user input device 35 such as a remote control device is received by the user operation input receiving unit 33 and sent to the internal reproduction setting unit 27 and also sent to the external input setting unit 43. Regarding the control of the external device, an external output setting unit 51, an external output control unit 47, an external input control unit 45, and an external input setting unit 43 are provided. The external output control unit 47 is an encrypted content. The encrypted content output from the recording unit 41 is acquired and sent to the network transmission / reception unit 53. The already encrypted content sent to the network transmission / reception unit 53 can be simultaneously distributed to the external devices 61-1 to 61-n via the network. Here, the external output can be controlled by the external output control unit 47 via the external output setting unit 51 by newly providing the multiple output control unit 57.

  Further, the content recording apparatus according to the present embodiment includes an external device control unit 55 and a multiple output control unit 57. The multiple output control unit 57 is configured to support simultaneous distribution of different contents from a plurality of external devices based on a device list / authentication list related to the external device acquired by the external device control unit 55 via the network transmission / reception unit 53. It has become. The external device control unit 55 includes an external device determination unit 55a that determines an external device and an external device authentication unit 55b that performs authentication of the external device.

  When a content is requested from an authenticated external device 61 registered in the list managed by the external device authentication unit 55b and connected to the network, the multiple output control unit 57 is sent from each control unit inside the external device 61. Based on the obtained operation load information and the network load status outside the device obtained from the network transmission / reception unit 53, control is performed to simultaneously output a plurality of contents to each external device 61. Here, the network-encrypted content and the corresponding decryption key (in this case, it is assumed that the content is encrypted so that it cannot be easily analyzed) are output to the external device that requested the content. Accordingly, it is not necessary to perform an encryption process when outputting the content, and different contents can be simultaneously distributed to the plurality of external devices 61 from the encrypted content stored in the encrypted content recording unit 41 in advance.

  The multiple output control unit 57 acquires a device list based on the determination from the external device determination unit 55a in order to respond to the simultaneous content transmission request from the plurality of external devices 61-n. This device list may be only the acquired external device list information, or may be any external device list information that is authenticated based on the authentication information provided from the external device authentication unit 55b. Further, the multiple output control unit 57 has a network management unit (not shown) that detects a network load via the network transmission / reception unit 53, and based on the network load information from the network management unit, Transaction management that manages internal and network loads and enables smooth content transmission with external devices. Thus, by managing content output control according to the load situation of the network, it is possible to cope with simultaneous distribution of different content to a plurality of external devices.

  Furthermore, the content decryption key management unit 37a that manages the content decryption key stored in the content decryption key storage unit 37b that stores a different content decryption key for each content, in response to an instruction from the multiple output control unit 57, the external output setting unit 51 The content decryption key management unit 37a is requested for the content decryption key necessary for decrypting the corresponding content, and the content decryption key management unit 37a decrypts the requested content decryption key. Obtained from the key management unit 37 b and sent to the external output control unit 47. At this time, information regarding which content is desired to be viewed from which external device, which is input from the external input setting unit 43, is sent to the encrypted content recording unit 41 via the external input control unit 45. Based on this information, the encrypted content recording unit 41 contacts the encrypted content information management unit 31 and sends the requested encrypted content to the external output control unit 47. In this way, the set of the encrypted content and the content decryption key sent to the external output control unit 47 is sent to the corresponding external device via the network transmission / reception unit 53. In addition, even when the user input device 35 sends it to the external input setting unit 43 via the user operation input receiving unit 33, the above processing is performed based on an instruction regarding which content is sent to which external device.

  On the other hand, regarding the content reproduction processing and the like performed inside the content recording apparatus A, which content is transmitted from the user input device 35 to the internal reproduction setting unit 27 via the user operation input receiving unit 33, is reproduced and fast-forwarded. Based on this instruction, the internal playback control unit 25 acquires content from the encrypted content recording unit 41, sends it to the network decryption unit 11b, and is decrypted from the playback output unit 15 to the display device 17. The displayed content is sent, and the display device 17 displays the content.

  As described above, the content recording apparatus according to this embodiment encrypts the acquired content in advance and then records the content in the encrypted content recording unit. That is, before recording the content distributed over the broadcast or the network in the encrypted content recording unit 41, the encryption used in the home network is performed in advance and stored together with the decryption key. Thereby, it can be displayed on the display device 17. Furthermore, the content requested from the external device via the network can be transmitted to the external device to allow viewing and the like. Here, in order to respond to simultaneous transmission requests from multiple devices, external device information is acquired and managed based on the network load status, external device list, etc., and the load on the device and on the network is managed In addition, by providing multiple output control units that perform transaction management that enables smooth transmission of content between devices, it is possible to simultaneously distribute different content without causing loss of content data due to an increase in network load. It becomes possible. At this time, the encrypted content, a decryption key for decrypting the encrypted content, and the encrypted content are paired and transmitted to the external device via the network, so that the content can be easily reproduced on the external device. By adopting such a configuration, the number of network encryption units can be determined according to circumstances on the own device side such as how many contents are simultaneously acquired from the tuner or the network.

  1 may be realized using a dedicated LSI, or may be executed by a program executed on a high-performance MCU (micro control unit (processor)). .

  Further, if the content is always in the same encrypted state and the decryption key is the same, it cannot be said that there is no possibility that the encryption is broken. Therefore, there may be a function of generating another key again and performing encryption again after a certain period of time. When re-encryption is performed, the content may not be being used from the outside, and the content from the outside may not be encrypted, but may be configured at a timing when the load on the device is low. Instead of re-encrypting the content at once, the content may be partially re-encrypted little by little at a fixed timing.

  FIG. 6A shows an example of a device list of external devices according to the present embodiment. Whether the external device list includes, for example, external device ID (1 to 5), device name, device type such as TV, recorder, PC, etc., whether it is a client or a server, or has both functions Content capability. The device list of the external device is stored in the external device authentication unit 55b. Further, as shown in FIG. 6B, the list may include an authentication result for each external device.

  Next, the flow of processing related to the above configuration will be described. First, the flow of processing during internal recording of content will be described with reference to FIG. 2A. First, the process is started in step S1, the tuner 3 selects a channel in step S2, the broadcast encryption / decryption unit 5 decrypts the encryption applied during the broadcast in step S3, and the partialization in step S4. The unit 7 performs partialization and acquires necessary information from the content data. In step S5, the network encryption unit 11a performs network encryption corresponding to the network to which the device is connected. In step S6, the encrypted content is stored in the encrypted content recording unit 41. In step S7, the content encryption is performed. The key is stored in the content decryption key storage unit 37b. This makes it possible to create and store network-encrypted content and a content decryption key for decrypting the content.

  FIG. 3 is a flowchart showing the flow of processing when content is internally reproduced. As shown in FIG. 3, in step S11, the process is started. When an encrypted content to be reproduced is selected in step S12, the process proceeds to an encrypted content reproduction process in step S13. In step S14, a content decryption key is entered. Using the decryption key stored in the storage unit 37b, the encrypted content is decrypted. In step S15, playback content output control is performed, and in step S16, playback content display output is performed. Thereby, the encrypted content recorded in the content recording device can be reproduced. In step S17, the process ends.

  Next, a flow of processing when content is output to an external device, which is a feature of the content reproduction technology according to the embodiment of the present invention, will be described with reference to the drawings. As shown in FIG. 4, in step S21, the process is started. First, when external output of encrypted content is requested in step S22, in step S23, it is authenticated whether or not the external device that requested the content is a device that can output the content with reference to the external device list. If the result of the device authentication results in an error (NG), the process is terminated without transmitting the content because it is not the content transmission target (step S24). If the result of the device authentication is successful (OK), since it is a content transmission target, the process proceeds to step S25, and it is determined whether or not there are a plurality of output requests simultaneously.

  If the current state of the device is not a plurality of simultaneous outputs, that is, if an output request is for only one content (NO), the process proceeds to step S26, the content decryption key is transmitted, and the encrypted content is transmitted in step S27. Is decrypted with the content decryption key to reproduce the encrypted content. When the reproduction of the content is completed in step S28, the process proceeds to step S24 and the process is terminated.

  If it is determined in step S25 that content is currently being output to an external device and there is an additional output request for different content (YES), it is determined in step S29 whether the content is in an internal state in which simultaneous output of multiple content is possible. Determine whether. In the case where the output is NG from the viewpoint of the access load to the encrypted content recording unit or the like (when output is impossible), in step S30, the improvement of the internal state (load to the encrypted content recording unit) is waited, If it is not improved, the output is impossible in step S31 to notify the external device that has requested the content, and the process is terminated (step S24). The load of the internal state is determined mainly based on the load state of the encrypted content recording unit, the internal data bus, and each control unit. If it is OK in step S29, the process proceeds to step S32 to determine the network load status. For this purpose, load information related to data transfer is acquired from each network transmission / reception unit, and a plurality of output control units determines whether or not new content output is possible from the viewpoint of network load. If the determination is NG, the process proceeds to step S33, waits for improvement of the network load status, and if not improved, the process proceeds to step S34, notifies the external device that requested the content that output is impossible, and ends the process (step S24). . If the network load status is OK, the process proceeds to step S35, the content decryption key is transmitted to the external device, the encrypted content is transmitted to the external device in step S36, and the content is decrypted with the content decryption key. Reproduce. When the reproduction of the content is finished in step S37, the process is also finished (step S24). By doing so, it is possible to simultaneously transmit a plurality of contents.

  FIG. 5 is a flowchart showing the flow of processing during re-encryption. If the content is always in the same encrypted state and the decryption key is the same, it cannot be said that there is no possibility of breaking the encryption. Therefore, after a certain period of time, there may be a function of generating another key again and performing encryption again. When re-encrypting, the content is not being used from the outside, and the content from the outside is not encrypted or decrypted. Alternatively, the content may be partially executed at a fixed timing instead of being re-encrypted at a time.

  First, the process is started (start) in step S41, and the encrypted content recording time is checked in step S42. Next, in step S43, it is determined whether or not a certain period has elapsed. If the predetermined period has not elapsed (NO), re-encryption is not performed (step S48: end). If the predetermined period has elapsed (YES), the process proceeds to step S44, where the encrypted content is decrypted. In step S45, an encryption key is newly created. In step S46, the content is re-encrypted with the new encryption key. Next, a decryption key for decrypting the encrypted content is stored in association with the content (step S47), and the process ends (step S48).

  With this configuration, encrypted content can be safely distributed even when content transmission is requested from a plurality of external devices.

  Next, a content recording apparatus according to a second embodiment of the present invention will be described with reference to the drawings. FIG. 7 is a functional block diagram showing a configuration example of the content recording apparatus B according to the present embodiment. The difference from FIG. 1 is that an integrated control unit 71 is provided. The integrated control unit 71 is a module that controls each control unit in an integrated manner and manages them centrally. From this integrated control unit 71, information on the load on the entire device and on the network and whether external input or internal reproduction is in progress is received, and it is determined whether or not output is possible. In this case, the multiple output control unit 57 receives from the integrated control unit 71 information about whether each part of the device such as the encrypted content recording unit and the load on the network and whether external input or internal playback is in progress, This is a functional unit that performs only an intermediary function that informs the external output setting unit 51 of whether content can be output to an external device. The contents of the processing are almost the same as those in the first embodiment. Which of the first embodiment and the second embodiment is to be selected is, for example, the second embodiment if the CPU has a high capability and can be easily managed by the integrated control unit. It is preferable to select the configuration of the first embodiment when selecting and distributing the load of each functional unit.

  Next, a content recording apparatus according to a third embodiment of the present invention will be described with reference to the drawings. The content recording apparatus according to this embodiment uses a copyright management system having a mechanism in which an encryption key / decryption key is different for each device.

  In this way, the content is accumulated by counting the content usage results from the external device 61-n. For example, the external device with the highest use frequency is specified by the external device determination unit 55a, or the user selects which one at the time of recording. Encryption is performed with an encryption key suitable only for the external device selected by the user input device 35 for designating whether to view the content to be recorded on the external device. The encrypted content information is inserted into the content list information only when the content list is requested from the device. Accordingly, it is possible to configure so that content can be selected only from the device. Even if the content can be selected, the content cannot be viewed if there is no decryption key corresponding to the external device. With such a configuration, it is possible to limit devices that can view content.

  FIG. 11 is a data configuration diagram showing an example of management information of the encrypted content information management unit 31 shown in FIG. In the example of the management information shown in FIG. 11, with respect to contents 1 to 5, the encryption classification (all devices, individual, etc.), the output target (all external devices, external devices 1, 2, etc.), the encryption Status (completed, external device n being encrypted, etc.) is managed. In this way, by managing the encrypted content information with the encrypted content management unit 31, it is possible to limit the devices that can view the content.

  FIG. 12 is a diagram showing a configuration example of management information in the content decryption key management unit 37a of FIG. As shown in FIG. 12, the content decryption key management information stores, for example, content 1 to 5, external devices 1 to 5, and a decryption key for reproducing the own device. It is shown that there is a case where a decryption key for a certain content is not stored depending on the external device. In addition, there is a case where information indicating whether the content is being encrypted or not encrypted is indicated. Even for the same content, different decryption keys are stored for each external device. FIG. 12 shows an example in which the same decryption key is managed even for different contents in the external device, but different management information (decryption key) may be provided for each content.

  FIG. 2B is a flowchart showing a flow of processing for performing network encryption at the time of recording and storing information on the target device according to the present embodiment. The difference from the flowchart shown in FIG. 2A is that content output target information is stored as step S8 '. This content output target information is information on an external device that is frequently used or an external device designated from the input device 35 (FIG. 1), and stores this information.

  In FIG. 6B, for each external device, the model name, type, content capability, whether or not device authentication has been processed, whether or not key information has been acquired, and encryption key information. Show. Information regarding whether or not a necessary key has been acquired from an external device and information on an encryption key are stored.

  FIG. 9 is a flowchart showing the flow of processing at the time of content request from an external device to be connected according to the present embodiment, and corresponds to FIG. 4 of the first embodiment. The difference from FIG. 4 is that in step S23 ', it is determined whether the encrypted content output request in step S22 is a request from the output target device. If it is a request from the output target device (YES), it is determined in step S23 whether or not simultaneous output is performed, and the subsequent processing is the same as in FIG.

  FIG. 10 is a flowchart showing the flow of processing when creating encrypted content corresponding to different encryption keys. This is an encryption process in all external devices. As shown in FIG. 10, first, processing is started in step S101, and in step S102, the encryption state of the encrypted content is investigated. In step S103, it is determined whether or not all devices are supported. In the case of YES, it progresses to step S108 and complete | finishes a process. In the case of NO, the process proceeds to step S104, and the encrypted content is decrypted. In step S105, an encryption key is newly created. In step S106, the content is re-encrypted with the new encryption key. Next, a decryption key for decrypting the encrypted content is stored in association with the content (step 107), and the process is terminated (step S108).

  With this configuration, encrypted content can be safely distributed even when content transmission is requested from a plurality of external devices.

  Next, a content recording apparatus according to a fourth embodiment of the present invention will be described with reference to the drawings. The content recording apparatus according to this embodiment uses a copyright management system having a mechanism in which an encryption key / decryption key is different for each device.

  In the present embodiment, the content is set in a state that can be viewed only by a specific user by performing a process such as setting a password for viewing the content by a user operation. And it encrypts with the encryption key suitable for the external apparatus (for example, 61a) connected to the network. Only when the content list is requested from the external device 61a and a password suitable for the user who views the content is received, the encrypted content information is inserted into the content list information, and the content can be selected only from the external device 61a. Configure to not. By configuring so that the content can be viewed only from the external device for which the user has entered the correct password, the users who can view the content can be restricted based on the content. In the present embodiment, the content output target information storage process of step S8 ′ in FIG. 2B is encrypted content in the content list information only when a password suitable for the user viewing the content is received. This is a process of storing a password in the case where information is inserted and the content can be viewed only from the device. In other words, this password specifies the content output target device.

  It should be noted that the present embodiment can also be described by using the above description in FIG. 6B and FIGS. 9 to 12.

  Next, a content recording apparatus according to a fifth embodiment of the present invention will be described with reference to the drawings. The content recording apparatus according to this embodiment uses a copyright management system having a mechanism in which an encryption key / decryption key is different for each device. It should be noted that the present embodiment can also be described by using the above description in FIG. 6B and FIGS. 9 to 12.

  In the present embodiment, the same content is counted by accumulating the count of content usage results, for example, by means of specifying an external device with the highest usage frequency, or an external device selected and specified by the user during recording Encrypt once with the encryption key. Thereafter, when the network encryption unit 11a is not used, an encrypted content encrypted with the encryption key of another device is created, and the same content encrypted with a plurality of encryption keys is stored in the encrypted content recording unit. Save several. As a result, encryption processing is performed in series, and the network encryption unit 11a can be used effectively and efficiently. It is also possible to realize a content recording apparatus that simultaneously distributes different contents to a plurality of external devices.

  The present invention can be used for a content recording apparatus.

A ... content recording device, 1 ... antenna, 3 ... tuner, 5 ... broadcast encryption / decryption unit, 7 ... partialization unit, 11 ... network encryption / decryption unit, 11a ... network encryption unit, 11b ... network decryption unit , 15 ... Playback output unit, 41 ... Encrypted content recording unit, 21 ... Internal recording setting unit, 23 ... Internal recording control unit, 25 ... Internal playback control unit, 27 ... Playback setting unit, 31 ... Encrypted content information management unit 57 ... multiple output control units, 71 ... integrated control unit.

Claims (6)

Content having a content acquisition unit that acquires content, a content recording unit that records the acquired content, and a network transmission / reception unit that transmits the content recorded in the content recording unit to a plurality of external devices via a network In the recording device,
An encrypted unit for encrypting the content is provided between the content acquisition unit and the content recording unit to record the encrypted content in the content recording unit, and to connect to the content recording device via a network when requested content from one of a plurality of external devices which are, after performing device authentication of the device, have a plurality output control unit which performs control to transmit the encrypted content to each requesting external device ,
The plurality of external devices are configured to be able to set an encryption key / decryption key for each device,
The external device determination unit counts the usage results of the content from the external device, and the user is selected by specifying an external device with a high accumulated usage record or an external device for viewing the content received by the user operation input reception unit. The content is encrypted with an encryption key suitable only for the external device, and recorded in the content recording unit,
Only when the content list is requested from the external device, the content information is transmitted to the content list information to the external device, and when the content is requested from the external device by a user selection process, the encryption is performed. A content recording apparatus characterized by transmitting a decryption key corresponding to an encrypted content to the external device, and limiting a device from which a user can view the content.   A content decryption key storage unit that stores a decryption key created according to the encryption process in the encryption unit in association with the encrypted content, and the plurality of output control units are content corresponding to the encrypted content 2. The content recording apparatus according to claim 1, wherein a decryption key is paired and transmitted to the requesting external device. Content having a content acquisition unit that acquires content, a content recording unit that records the acquired content, and a network transmission / reception unit that transmits the content recorded in the content recording unit to a plurality of external devices via a network In the recording device,
An encrypted unit for encrypting the content is provided between the content acquisition unit and the content recording unit to record the encrypted content in the content recording unit, and to connect to the content recording device via a network A plurality of output control units that perform control to transmit encrypted content to each requesting external device after performing device authentication when the content is requested from any of the plurality of external devices ,
The plurality of external devices are configured to be able to set an encryption key / decryption key for each device,
After encrypting the same content by means of counting the content usage results and identifying external devices with high accumulated usage results or once with the encryption key of the external device selected and selected by the user during recording, In a period when the encryption unit is not used, an encrypted content encrypted with an encryption key of another external device is created, and a plurality of the same content encrypted with a plurality of encryption keys is stored in the encrypted content recording unit. features and to Turkey content recording device that you save. The multiple output control unit includes a network management unit that detects a network load via the network transmission / reception unit, and the load on the external device and the network based on network load information from the network management unit content recording apparatus according to any one of claims 1, wherein up to 3 to manage. The multiple output control unit determines whether or not content can be transmitted to an external device based on information from an external device determination unit having a device list of the external device connected via a network. The content recording device according to any one of claims 1 to 4 . Re-encryption that generates another encryption key again and re-encrypts the content after a certain time has passed with respect to the encryption of the encrypted content recorded in the encrypted content recording unit content recording apparatus according to item 1 any one of claims 1 to 5, characterized in that it has a function.

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