Abstract:
A transmission apparatus updates the encryption method in the event the encryption method is broken. The tool ID of a decryption tool for encrypted data is acquired, the presence of the tool is confirmed and the tool is then acquired and updated, and encrypted data is processed and transmitted based on rights information associated with the encrypted data.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    The present invention relates to an apparatus for sending and to an apparatus for receiving a digital broadcast signal having multiplexed program information and video content coded for image compression.  
           [0003]    2. Description of Related Art  
           [0004]    [0004]FIG. 15 is a block diagram of a prior art transmission apparatus  502  and receiving apparatus  503 . As shown in FIG. 15 the transmission apparatus  502  has an MPEG-2 Video-compliant (ISO/IEC 13818-2) video encoder  56 , an MPEG-2 Audio-compliant (ISO/IEC 13818-3) audio encoder  57 , program-specific information generator  59 , and an MPEG-2 Systems-compliant (ISO/IEC 13818-1) multiplexer  66 .  
           [0005]    The receiving apparatus  503  has a demultiplexer  107 , video decoder  112 , and audio decoder  113 .  
           [0006]    Also shown in the figure are the digital video input signal  49 , digital audio input signal  50 , audio bitstream  64 , video bitstream  76 , program-specific information  500 , multiplexed bitstream  501 , video bitstream  110 , audio bitstream  126 , digital video signal  111 , and digital audio signal  114 .  
           [0007]    The video encoder  56  of this prior art transmission apparatus  502  compresses the digital video input signal  49  according to the MPEG-2 Video standard to output video bitstream  76 . The digital audio input signal  50  is similarly compression-coded by the audio encoder  57  to output MPEG-2-compliant audio bitstream  64 . The program-specific information generator  59  generates program-specific information (“PSI” below)  500  describing the relationship between the video bitstream  76 , audio bitstream  64 , and program number. The multiplexer  66  then multiplexes the video bitstream  76 , audio bitstream  64 , and PSI  500  and outputs multiplexed bitstream  501 .  
           [0008]    The demultiplexer  107  of this prior art receiving apparatus  503  then demultiplexes the received multiplexed bitstream  501  into the video bitstream  110  and audio bitstream  126 . The video bitstream  110  is then decompressed by the video decoder  112  and output as digital video signal  111 . The audio bitstream  126  is likewise decompressed by the audio decoder  113  and output as digital audio signal  114 .  
           [0009]    Problem to be Solved by the Invention  
           [0010]    A problem with the prior art system described above is that the audio and video bitstreams are not encrypted, and can be easily stolen by an unauthorized receiving apparatus.  
           [0011]    Another problem is that even if the bitstreams are encrypted there is no protection against the encryption method itself being broken. More specifically, there is no means for preventing unauthorized reception of data sent by the transmission apparatus.  
           [0012]    The present invention is directed to solving these problems, and an object of this invention is to provide protection assuring that data sent by the transmission apparatus can be safely received by the receiving apparatus.  
         SUMMARY OF THE INVENTION  
         [0013]    To achieve these objects a transmission apparatus according to a first aspect of the present invention has encryption means for encrypting data and producing first encrypted data; program-specific information generating means for producing program-specific information containing a table denoting the correlation between first encrypted data and a program number of the first encrypted data; tool list generating means for producing a tool list containing a tool ID indicating a decoding tool for decrypting the first encrypted data; control graph generating means for producing a control graph indicating the embedded or instantiated location of the decoding tool in the receiving apparatus; rights information generating means for producing rights information for the first encrypted data; and multiplexing means for multiplexing the first encrypted data, program-specific information, tool list, control graph, and rights information.  
           [0014]    A transmission apparatus according to a second aspect of the invention has encryption means for encrypting data and producing first encrypted data; tool list generating means for producing a tool list containing a tool ID indicating a decoding tool for decrypting the first encrypted data; control graph generating means for producing a control graph indicating the instantiated location of the decoding tool in the receiving apparatus; rights information generating means for producing rights information for the first encrypted data; and program-specific information generating means for producing program-specific information containing a table denoting the correlation between first encrypted data and a program number of the first encrypted data, the tool list, the control graph, and the rights information; and multiplexing means for multiplexing the first encrypted data and the program-specific information.  
           [0015]    A transmission apparatus according to a third aspect of the invention has encryption means for encrypting data and producing first encrypted data; tool list generating means for producing a tool list containing a tool ID indicating a decoding tool for decrypting the first encrypted data; control graph generating means for producing a control graph indicating the instantiated location of the decoding tool in the receiving apparatus; program-specific information generating means for producing program-specific information containing a table denoting the correlation between first encrypted data and a program number of the first encrypted data, the tool list, the control graph, and the rights information; and rights information generating means for producing rights information for this data; rights information transmission means for outputting the rights information; and multiplexing means for multiplexing and outputting the first encrypted data and the program-specific information.  
           [0016]    Preferably, the rights information transmission means relates the rights information to the data.  
           [0017]    Alternatively, the program-specific information generating means relates the rights information to the data.  
           [0018]    Further preferably, the multiplexing means multiplexes the decoding tool used for decryption.  
           [0019]    Yet further preferably, the multiplexing means multiplexes key information enabling decryption.  
           [0020]    A receiving apparatus according to an eighth aspect of the invention has demultiplexing means for separating a multiplexed signal containing first encrypted data into at least the first encrypted data and program-specific information; tool list demultiplexing means for separating a tool list having a tool ID indicating a decoding tool for decrypting the first encrypted data from the multiplexed signal; control graph demultiplexing means for separating a control graph indicating the instantiated location of the decoding tool in the receiving apparatus from the multiplexed signal; rights information demultiplexing means for demultiplexing rights information for the first encrypted data from the multiplexed signal; first control means for acquiring a tool according to a tool ID acquired from the tool list, and instantiating the tool according to the control graph; and first rights management means for processing the first encrypted data according to the rights information.  
           [0021]    A receiving apparatus according to a ninth aspect of the invention has demultiplexing means for separating a multiplexed signal containing first encrypted data into at least the first encrypted data and program-specific information; tool list demultiplexing means for separating a tool list having a tool ID indicating a decoding tool for decrypting the first encrypted data from the multiplexed signal; control graph demultiplexing means for separating a control graph indicating the instantiated location of the decoding tool in the receiving apparatus from the program-specific information; rights information demultiplexing means for demultiplexing rights information for the first encrypted data from the program-specific information; first control means for instantiating a tool with a tool ID acquired from the tool list according to the control graph; and first rights management means for processing the first encrypted data according to the rights information.  
           [0022]    A receiving apparatus according to a tenth aspect of the invention has demultiplexing means for separating a multiplexed signal containing first encrypted data into at least the first encrypted data and program-specific information; tool list demultiplexing means for separating a tool list having a tool ID indicating a decoding tool for decrypting the first encrypted data from the multiplexed signal; control graph demultiplexing means for separating a control graph indicating the instantiated location of the decoding tool in the receiving apparatus from the program-specific information; first control means for instantiating a tool with a tool ID acquired from the tool list according to the control graph; rights information receiving means for receiving rights information for the first encrypted data; and first rights management means for processing the first encrypted data according to the rights information.  
           [0023]    Preferably, the receiving apparatus also has temporary storage means for temporarily storing the received first encrypted data; and reading means for reading the first encrypted data stored to the temporary storage means.  
           [0024]    Yet further preferably, the receiving apparatus also has file management means for deleting from the temporary storage means the first encrypted data after the playback permit recorded in the rights information is expired.  
           [0025]    Yet further preferably, the rights management means sends status information indicating how the first encrypted data was processed.  
           [0026]    Yet further preferably, the receiving apparatus also has rights management means for separating the rights information into first rights information and second rights information; multiplexing adjusting means for rewriting rights information in the multiplexed signal to second rights information, and outputting a revised multiplexed signal. The revised multiplexed signal in this case is output to a second receiving apparatus according to a request signal from the second receiving apparatus.  
           [0027]    Alternatively, the receiving apparatus also has rights management means for separating the rights information into first rights information and second rights information; wherein the second rights information and multiplexed signal are output to a second receiving apparatus according to a request signal from the second receiving apparatus.  
           [0028]    Yet further preferably, the rights management means in one receiving apparatus receives data indicating how the first encrypted data was processed by a second receiving apparatus, and sends status information describing processing by said one receiving apparatus and the second receiving apparatus.  
           [0029]    Yet further preferably, the receiving apparatus also has conversion means for converting the first encrypted data to second encrypted data; and remultiplexing means for remultiplexing the second encrypted data with the second rights information.  
           [0030]    Yet further preferably, the first encrypted data is processed according to the first rights information.  
           [0031]    Yet further preferably, the receiving apparatus also has file management means for deleting the first encrypted data from the temporary storage means after sending it to a second receiving apparatus.  
           [0032]    Yet further preferably, the receiving apparatus also has video decoding means for extracting and decoding video data from the multiplexed signal, and/or audio decoding means for extracting and decoding audio data from the multiplexed signal.  
           [0033]    Other objects and attainments together with a fuller understanding of the invention will become apparent and appreciated by referring to the following description and claims taken in conjunction with the accompanying drawings. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0034]    [0034]FIG. 1 is a schematic block diagram of a transmission apparatus according to a first embodiment of the present invention;  
         [0035]    [0035]FIG. 2 is a control graph showing operation of the first embodiment of the invention;  
         [0036]    [0036]FIG. 3 is a schematic block diagram of a transmission apparatus according to a second embodiment of the present invention;  
         [0037]    [0037]FIG. 4 is a schematic block diagram of a receiving apparatus according to a third embodiment of the present invention;  
         [0038]    [0038]FIG. 5 is a schematic block diagram of a receiving apparatus according to a fourth embodiment of the present invention;  
         [0039]    [0039]FIG. 6 is a schematic flow chart showing the operation of the second rights manager in a fourth embodiment of the present invention;  
         [0040]    [0040]FIG. 7 shows the structure of the multiplexed bitstream in a fourth embodiment of the present invention;  
         [0041]    [0041]FIG. 8 is a schematic block diagram of a receiving apparatus according to a fifth embodiment of the present invention;  
         [0042]    [0042]FIG. 9 is a schematic block diagram of a receiving apparatus according to a sixth embodiment of the present invention;  
         [0043]    [0043]FIG. 10 is a schematic block diagram of a receiving apparatus according to a seventh embodiment of the present invention;  
         [0044]    [0044]FIG. 11 is a schematic block diagram of a receiving apparatus according to an eighth embodiment of the present invention;  
         [0045]    [0045]FIG. 12 is a schematic block diagram of a receiving apparatus according to a ninth embodiment of the present invention;  
         [0046]    [0046]FIG. 13 is a schematic block diagram of a receiving apparatus according to a tenth embodiment of the present invention;  
         [0047]    [0047]FIG. 14 shows the system configuration of an eleventh embodiment of the present invention; and  
         [0048]    [0048]FIG. 15 is a schematic block diagram of the prior art. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0049]    Preferred embodiments of the present invention are described below with reference to the accompanying FIGS.  1  to  14 .  
       Embodiment 1  
       [0050]    [0050]FIG. 1 is a block diagram showing a transmission apparatus according to a first embodiment of the present invention. In FIG. 1 the digital video input signal  49 , digital audio input signal  50 , video encoder  56 , audio encoder  57 , audio bitstream  64 , and video bitstream  76  are the same as in the prior art configuration shown in FIG. 15. Also shown in FIG. 1 are a rights information generator  51 , tool list generator  52 , control graph generator  53 , stream information generator  58  encryption means  60 , program-specific information generator (below, “PSI generator”)  61 , an MPEG-2 Systems-compliant (ISO/IEC 13818-1) multiplexer  62 , encrypted video bitstream  63 , program-specific information  65 , multiplexed bitstream  66 , rights information  67  produced by the rights information generator  51 , a tool list  68  produced by the tool list generator  52 , a control graph  69  produced by the control graph generator  53 , stream information  72 , first transmission apparatus  73 , status information  74 , transmission control means  75 , rights control information  81 , tool control information  82 , graph control information  83 , and decoding tool  115 .  
         [0051]    It should be noted that the encryption means  60  uses a 128-bit key for AES-compliant (Advanced Encryption Standard) encryption.  
         [0052]    Referring to FIG. 1, the digital video input signal  49  is compression-coded to an MPEG-2-compliant video bitstream  76  by the video encoder  56 , and then encrypted by a first encryption means  60  for output as encrypted video bitstream  63 .  
         [0053]    The digital audio input signal  50  is similarly compression-coded by the audio encoder  57 , and output as audio bitstream  64 ;  
         [0054]    Exemplary status information  74  is shown in Table 1. The values in Table 1 are 8-bit words of bits  7  to  0 . Status information and content is exchanged between a transmission apparatus with a transmission device ID, and a receiving apparatus with a receiving device ID. The status information contains the value fields shown in the left column of Table 1. The corresponding field values (content) are shown in the right column.  
                                     TABLE 1                                   Status information                                        Tool request   0X10000000           Content request   0X01000000           Copy information   0X00100000           Playback count   0X00010000           Editing   0X00001000                      
 
         [0055]    The rights information generator  51  produces rights information specifying the conditions under which a user is permitted to use the encoded content stream, and supplies the rights information to the PSI generator  61 . The values shown in Table 2 are written to the corresponding content (value) fields in Table 1 to specify the rights for copying, playing (tracked using a playback count), or editing the encoded bitstream content.  
         [0056]    It should be noted that a program as used herein means an AV program with added program-specific information.  
                                                           Copying   once   0X00000000               prohibited   0X00000001           Playback count       1Xnnnnnnnn           Editing   allowed   0X00000010               prohibited   0X00000011                      
 
         [0057]    This first embodiment of the invention enables two types of programs, A and B. Program type A is sent with the values shown in Table 3, enabling the program to be copied once, played once, but not edited.  
                               TABLE 3                                   Content       Program A                           Copying   once   0X00000000           Playback count       1X00000001           Editing   prohibited   0X00000011                      
 
         [0058]    User actions (rights) allowed with program type B are sent as shown in Table 4, enabling the program to be copied once, played three times, but not edited.  
                               TABLE 4                                   Content       Program B                           Copying   once   0X00000000           Playback count       1X00000003           Editing   prohibited   0X00000011                      
 
         [0059]    The transmission apparatus  73  is assumed to recognize that there is a decoding tool  115  having a tool ID (0X00A) enabling AES decryption. The tool list generator  52  generates a list of tools required on the receiver side, and passes this list to the PSI generator  61 . More specifically, the tool list generator  52  produces a tool list with the above-noted tool ID (0X00A) indicating that decoding tool  115  is required to receive and play the MPEG-2 Video bitstream.  
         [0060]    The configuration of the control graph  69  is shown in part in FIG. 2. Program A contains encrypted video bitstream  63  and audio bitstream  64 , a tool ID for the encrypted video bitstream  63 , and a control point indicating the location of the tool. Program B is similarly configured.  
         [0061]    The control graph generator  53  produces a control graph  69  indicating that the tool having the tool ID (0X00A) enabling AES decryption is located directly before the video decoder of the receiving apparatus, and outputs the control graph  69  to the PSI generator  61 .  
         [0062]    The PSI generator  61  generates program-specific information  65  containing rights information  67 , tool list  68 , control graph  69 , and a relation table indicating the relationship between the encrypted video bitstream  63 , audio bitstream  64 , and program number of the program.  
         [0063]    The stream information generator  58  produces stream information  72  containing key information and other data for decrypting the encryption applied by the encryption means  60 .  
         [0064]    The multiplexer  62  multiplexes the encrypted video bitstream  63 , audio bitstream  64 , program-specific information  65 , stream information  72 , and decoding tool  115  to conform with the MPEG-2 Systems standard, and thus outputs multiplexed bitstream  66 .  
         [0065]    By receiving status information  74  from another device, the transmission control means  75  can know how the rights information  67  approved by a transmission apparatus according to this first embodiment of the invention was processed by another device. If the rights information for program B shown in Table 4 is received by a transmission apparatus according to this embodiment of the invention as status information  74  shown in Table 5, the transmission apparatus knows that the content was copied once and played twice.  
                               TABLE 5                                   Content       Program B                           Copying   prohibited   0X00000001           Playback count       1X00000001           Editing   prohibited   0X00000011                      
 
         [0066]    As described above the multiplexed bitstream downloaded to the receiving apparatus in the present invention includes with the encrypted data a tool list for content decryption, the decryption tool, the tool location, decryption key information, and rights information. The transmission apparatus according to this embodiment of the present invention can therefore always provide the most recent protection, and can process the protection method as part of the program-specific information in the multiplexed data.  
         [0067]    The rights information  67 , tool list  68 , and control graph  69  are applied to the PSI generator  59  in this first embodiment described above, but it could be applied directly to the multiplexer  62 . A simpler transmission apparatus can be provided in this case because the rights information  67 , tool list  68 , and control graph  69  are not contained in the program-specific information.  
       Second Embodiment  
       [0068]    [0068]FIG. 3 is a block diagram of a transmission apparatus according to a second embodiment of the invention. It should be noted that like parts in FIG. 3, FIG. 15, and FIG. 1 are identified by like reference numerals. This second embodiment differs from the first in the rights information transmission means  84 , transmission rights information  85 , and second transmission apparatus  86 .  
         [0069]    Referring to FIG. 3, the digital video input signal  49  is compressed to an MPEG-2-standard video bitstream  76  by the video encoder  56 , then encrypted by the encryption means  60  and output as encrypted video bitstream  63 . The digital audio input signal  50  is similarly compressed by the audio encoder  57 , and output as audio bitstream  64 .  
         [0070]    The status information  74  in this case is as shown in Table 1. The rights information generator  51  produces rights information declaring content usage conditions for a content stream, and supplies the rights information to the rights information transmission means  84 . The rights information  67  is shown in Table 6 in this case.  
                               TABLE 6                                       Copying   once   0X00000000               prohibited   0X00000001           Playback count       1Xnnnnnnnn           Editing   allowed   0X00000010               prohibited   0X00000011                      
 
         [0071]    This second embodiment of the invention enables two types of programs, A and B. Program type A is sent with the values shown in Table 7, enabling the program to be copied once, played once, but not edited. The rights information shown in Table 7 corresponds to the user actions allowed with program A.  
                               TABLE 7                                   Content       Program A                           Copying   once   0X00000000           Playback count       1X00000001           Editing   prohibited   0X00000011                      
 
         [0072]    User actions (rights) allowed with program type B are sent as shown in Table 8, enabling the program to be copied once, played three times, but not edited. The rights information shown in Table 8 corresponds to the user actions allowed with program B.  
                               TABLE 8                                   Content       Program B                           Copying   once   0X00000000           Playback count       1X00000003           Editing   prohibited   0X00000011                      
 
         [0073]    The transmission apparatus  86  is assumed to recognize that there is a decoding tool  115  having a tool ID (0X00A) enabling AES decryption. The tool list generator  52  generates a list of tools required on the receiver side, and passes this list to the PSI generator  61 . More specifically, the tool list generator  52  produces a tool list  68  with the above-noted tool ID (0X00A) indicating that the decoding tool  115  is required to receive and play the MPEG-2 Video bitstream.  
         [0074]    The configuration of the control graph is shown in FIG. 2. Program A contains a first encrypted video bitstream  63  and audio bitstream  64 , a tool ID for the first encrypted video bitstream  63 , and a control point denoting the location of the tool. Program B is similarly configured.  
         [0075]    The control graph generator  53  produces a control graph  69  indicating that the tool having the tool ID (0X00A) enabling AES decryption is located before the video decoder of the receiving apparatus, and outputs the control graph  69  to the PSI generator  61 .  
         [0076]    The PSI generator  61  generates program-specific information  65  containing tool list  68 , control graph  69 , decoding tool  115 , and a relation table indicating the relationship between the encrypted video bitstream  63 , audio bitstream  64 , and program number of the program.  
         [0077]    The stream information generator  58  produces stream information  72  containing key information and other data for decrypting the encryption applied by the encryption means  60 .  
         [0078]    The multiplexer  62  multiplexes the encrypted video bitstream  63 , audio bitstream  64 , program-specific information  65 , and stream information  72  to conform with the MPEG-2 Systems standard, and thus outputs multiplexed bitstream  66 .  
         [0079]    The rights information transmission means  84  relates rights information  67  to a specific program. This correlation with a particular program is possible because a relation table denoting the relationship between the encrypted video bitstream  63 , audio bitstream  64 , and program number of the program can be obtained by communication with the PSI generator  61 , and can then be converted to a file for transmission as transmission rights information  85 .  
         [0080]    The rights information can be handled separately from the multiplexed data because the rights information is sent separately from the multiplexed data, and the rights information can therefore be rewritten and sent to another receiving apparatus without the first receiving apparatus remultiplexing the content data.  
         [0081]    By receiving status information  74  from another device, the transmission control means  75  can know how the rights information  67  approved by a transmission apparatus according to this second embodiment of the invention was processed by another device. If the rights information for program B shown in Table 8 is received by a transmission apparatus according to this embodiment of the invention as the rights information shown in Table 9, the transmission apparatus knows that the content was copied once and played twice.  
                               TABLE 9                                       Copying   prohibited   0X00000001           Playback count       1X00000001           Editing   prohibited   0X00000011                      
 
         [0082]    As described above the tool list for content decryption, the decryption tool, the tool location, decryption key information, and rights information can be downloaded with the encrypted data as part of the multiplexed data to the receiving apparatus. As a result, the tools can be updated, and the most recent protection tools can always be provided. Furthermore, because the rights information can be sent as a file separately to the multiplexed data, a transmission apparatus of our invention does not need to re-multiplex the content bitstream when one receiving apparatus rewrites and sends the rights information to another receiving apparatus.  
         [0083]    In addition to the above benefits, the transmission apparatus according to this embodiment of the invention can correctly relate rights information to the multiplexed data when multiple multiplexed data streams are present because the rights information can be sent separately from the multiplexed data and the rights information can be linked to a particular multiplexed data stream.  
       Third Embodiment  
       [0084]    [0084]FIG. 4 is a block diagram of a receiving apparatus according to a third embodiment of the present invention. In FIG. 4 reference numerals  111  to  114  denote the same parts as indicated by the same reference numerals in the prior art example shown in FIG. 15. Also shown in FIG. 4 are a first receiving apparatus  100 , a first input multiplexed bitstream  101  conforming to the MPEG-2 Systems standard, a hard disk drive  102 , a read multiplexed bitstream  103  read from the hard disk drive  102  and input to demultiplexer  104 , instantiating means  108 , video bitstream  110 , decoding tool  115  for decrypting AES encryption, first control means  120 , first rights manager  121 , file management information  123 , file manager  124 , hard disk drive control command  125  applied to the hard disk drive  102 , read information  90  including stream information and decoding tool  115 , program-specific information (PSI) demultiplexer  91 , program-specific information  92 , control graph demultiplexer  93 , control graph information  94 , tool list demultiplexer  95 , tool list  96 , rights information demultiplexer  97 , rights information  98 , first reply information  132 , and first request information  137 .  
         [0085]    The first receiving apparatus  100  is connected to the first transmission apparatus  73 .  
         [0086]    Referring to FIG. 4, the MPEG-2 Systems-compliant first input multiplexed bitstream  101  is first stored to the hard disk drive  102 , and is then read from the disk drive  102  and applied to the demultiplexer  104  as read multiplexed bitstream  103 . The demultiplexer  104  separates the read multiplexed bitstream  103  into a first encrypted video bitstream  105 , audio bitstream  106 , program-specific information  92 , and read information  90 .  
         [0087]    The program-specific information  92  describes the relationship between the first encrypted video bitstream  105 , audio bitstream  106 , and program number of the program, as well as the rights information  98  for the program, tool list  96  containing the tool ID (0X00A) for AES decryption, and control graph  94  indicating that the decryption tool is instantiated between the demultiplexer  104  and video decoder  112  of the first receiving apparatus  100 . Key information for decrypting the first encrypted video bitstream  105  is also contained in the read information  90 .  
         [0088]    The read information  90  is then demultiplexed by the demultiplexer  104  and applied to the first control means  120 . The program-specific information  92  is applied to the PSI demultiplexer  91 . The control graph demultiplexer  93  extracts the control graph  94  from the PSI demultiplexer  91 , and supplies it to the first control means  120 . The tool list demultiplexer  95  extracts the tool list  96  from the PSI demultiplexer  91 , and supplies it to the first control means  120 . The rights information demultiplexer  97  extracts the rights information  98  from the PSI demultiplexer  91 , and supplies it to the first rights manager  121 .  
         [0089]    The first control means  120  transmits the first request information  137  as shown in Table 10. This first request information  137  sends a tool request and content (i.e., program) request.  
                           TABLE 10                                       Tool request   0X10000000           Content request   0X01000000                      
 
         [0090]    The first control means  120  knows from the tool list  96  that decoding tool  115  is the tool needed for decryption, knows from the control graph  94  that the control point for applying the decoding tool  115  is  108 , and extracts the descrambling key from the read information  90 .  
         [0091]    The first control means  120  sends a command for instantiating the decoding tool  115  and key information extracted from the read information  90  to the instantiating means  108  according to the control graph  94 , which indicates that the decoding tool  115  is instantiated between the demultiplexer  104  and video decoder  112  of the first receiving apparatus  100 . The instantiating means  108  then embeds the decoding tool  115  and key information. The first encrypted video bitstream  105  is then decrypted by the instantiating means  108 , and output as video bitstream  110 .  
         [0092]    The video bitstream  110  is then decompressed by the video decoder  112  and output as digital video signal  111 . The audio bitstream  106  is expanded by the audio decoder  113 , and output as digital audio signal  114 .  
         [0093]    The first rights manager  121  acquires the rights information  98 , and outputs file management information  123  to the file manager  124 . Because the playback count assigned with the value shown in Table 4 is only once with program A, the file manager  124  sends a hard disk drive control command  125  to the hard disk drive  102  to erase the stored program A once the program has been read once.  
         [0094]    The first rights manager  121  sends the information shown in Table 11 as the first reply information  132 . This reply shows that the program has been played once by the first receiving apparatus  100 .  
                               TABLE 11                                       Copying   allowed   0X00000000           No. times played by 1st receiver       1X00000001                      
 
       Fourth Embodiment  
       [0095]    [0095]FIG. 5 is a block diagram showing a receiving apparatus according to a fourth embodiment of the present invention. In this fourth embodiment of the invention a first receiving apparatus can download tools to another receiving apparatus connected via a network, can send digital data, and can send consumption information to the server.  
         [0096]    Referring to FIG. 5, reference numerals  111  to  114  denote the same parts as indicated by the same reference numerals in the prior art example shown in FIG. 15, and reference numerals  90  to  98 ,  101  to  106 ,  108 ,  110 ,  115 ,  123  to  125 , and  132  denote the same parts referenced thereby in the third embodiment.  
         [0097]    Also shown in FIG. 5 is a second receiving apparatus  130  having second rights information  133 , second reply information  136 , second rights manager  138 , second control means  139 , second request information  140 , first control information  141 , multiplexing adjustment means  142 , second MPEG-2 Systems-compliant multiplexed bitstream  143 , and tenth receiving apparatus  144 .  
         [0098]    [0098]FIG. 6 is a flow chart of the process run by the second rights manager  138 . FIG. 7 schematically shows the structure of the first multiplexed bitstream  103  and second multiplexed bitstream  143  where relation table  146  describes the relationship between the encrypted video bitstream  63 , audio bitstream  64 , and program number of program A.  
         [0099]    The second receiving apparatus  130  in FIG. 5 is connected to first transmission apparatus  73 , and the receiving apparatus  144  connected to the second receiving apparatus  130  is functionally equivalent to the first receiving apparatus  100  shown in FIG. 4.  
         [0100]    Referring again to FIG. 5, the read information  90  is demultiplexed by the demultiplexer  104  and applied to the second control means  139 . The second control means  139  sends rights approval information to the second rights manager  138 , and sends the first control information  141  containing multiplexed bitstream adjustment information to the multiplexing adjustment means  142 .  
         [0101]    The second control means  139  then receives the second request information  140  shown in Table 12 from the tenth receiving apparatus  144 . Table 12 shows that the receiving apparatus  144  is sending tool and content requests to the second receiving apparatus  130 .  
                           TABLE 12                                       Tool request   0X10000000           Content request   0X01000000                      
 
         [0102]    [0102]FIG. 6 shows part of the operation of the second rights manager  138 .  
         [0103]    Second request information  140  is received through the second control means  139  in step  1 , and rights information  98  is received in step  2 . The rights information  98  is then separated into the first rights information used by the second receiving apparatus  130  and the second rights information  133  used by the tenth receiving apparatus  144  in step  3 .  
         [0104]    The first rights information is output in step  4 , file management information  123  is output to the file manager  124  based on the first rights information in step  5 , and second rights information  133  is output in step  6 .  
         [0105]    If a program B with rights information set as shown in Table 4 is played once by the second receiving apparatus  130  and sent to the first receiving apparatus, the first and second rights information are respectively written as shown in Table 13 and Table 14. Note that because the program was played once by the second receiving apparatus  130 , the playback count shown in Table 14, denoting the second rights information sent to the tenth receiving apparatus  144 , is reduced one.  
                               TABLE 13                                       Copying   prohibited   0X00000001           Playback count       1X00000001           Editing   prohibited   0X00000011                      
 
         [0106]    [0106]                               TABLE 14                                       Copying   prohibited   0X00000001           Playback count       1X00000002           Editing   prohibited   0X00000011                        
         [0107]    The second rights manager  138  sends the second rights information  133  shown in Table 14 to the multiplexing adjustment means  142 . The multiplexing adjustment means  142  then modifies the content of the first multiplexed bitstream  103  based on the second rights information  133 . More specifically, the rights information  122  of the first multiplexed bitstream  103  is changed to the content of the second rights information  133 , and the result is output as second multiplexed bitstream  143 .  
         [0108]    [0108]FIG. 7 shows the configuration of the first and second multiplexed bitstreams. The rights information  98  is applied to the multiplexing adjustment means  142  as second rights information  133  by the second rights manager, and the second multiplexed bitstream  143  thus contains the second rights information.  
         [0109]    Based on the control graph  94  indicating that the instantiated location of the decoding tool  115  is between the demultiplexer  104  of the second receiving apparatus  130  and the video decoder  112 , the second control means  139  outputs a command to the instantiating means  108  to embed the decoding tool  115  and key information extracted from the read information  90 , and the instantiating means  108  then embeds the decoding tool  115  and key information. The first encrypted video bitstream  105  is decrypted by the instantiating means  108  and output as video bitstream  110 , and is then decoded by the video decoder  112  and output as the digital video signal.  
         [0110]    Operation is otherwise the same as in the third embodiment. A second receiving apparatus  130  according to this embodiment of the invention can therefore send received rights information, bitstreams, and tool information to a tenth receiving apparatus  144  connected thereto over a network.  
         [0111]    The second rights manager  138  then outputs the first reply information  132  based on the second reply information  136  from tenth receiving apparatus  144 . First reply information configured as shown in Table 15 is then output because the content stream was played once by second receiving apparatus  130  and once by tenth receiving apparatus  144 .  
                           TABLE 15                                       No. times played by 2nd receiver   0X00000001           No. times played by 1st receiver   0X00000001                      
 
         [0112]    The transmission apparatus according to this embodiment of the invention can thus acquire content consumption information from both the second receiving apparatus  130  and a tenth receiving apparatus  144  connected to the second receiving apparatus  130 .  
       Fifth Embodiment  
       [0113]    [0113]FIG. 8 is a block diagram showing a receiving apparatus according to a fifth embodiment of the present invention. This embodiment of the invention can download rights information received by a receiving apparatus, can send digital data to another receiving apparatus connected via a network, and can send consumption information to the server.  
         [0114]    Referring to FIG. 8, reference numerals  111  to  114  denote the same parts as indicated by the same reference numerals in the prior art example shown in FIG. 15, reference numerals  90  to  98 ,  101  to  106 ,  108 ,  110 ,  115 ,  123  to  125 ,  132  and  137  denote the same parts referenced thereby in the third embodiment shown in FIG. 4, and reference numerals  136  and  140  are the same as in the fourth embodiment shown in FIG. 5.  
         [0115]    Also shown in FIG. 8 are third receiving apparatus  150 , third rights information  153 , fourth receiving apparatus  154 , third controller  160 , and third rights manager  161 .  
         [0116]    In FIG. 8 the third controller  160  receives second request information  140  as shown in Table 16 from the fourth receiving apparatus  154 . Table 16 shows that the fourth receiving apparatus  154  is requesting a tool and content from the third receiving apparatus  150 . The third controller  160  sends rights approval information to the third rights manager  161 .  
                           TABLE 16                                       Tool request   0X10000000           Content request   0X01000000                      
 
         [0117]    The read information  90  is separated by the demultiplexer  104  and applied to the third controller  160 . The third rights manager  161  separates the rights information  98  into the first rights information used by the third receiving apparatus  150 , and the third rights information  153  used by the fourth receiving apparatus  154 , and sends the third rights information  153  to the fourth receiving apparatus  154 .  
         [0118]    If the content is played once by third receiving apparatus  150  and once by fourth receiving apparatus  154 , the first rights information and third rights information  153  are as shown in Table 17 and Table 18. Note that the playback count shown in Table 18 is reduced one because the content was played by the third receiving apparatus  150 .  
                               TABLE 17                                       Copying   prohibited   0X00000000           Playback count       1X00000001           Editing   prohibited   0X00000011                      
 
         [0119]    [0119]                               TABLE 18                                       Copying   prohibited   0X00000001           Playback count       1X00000002           Editing   prohibited   0X00000011                        
         [0120]    Operation is otherwise as described in the third embodiment. As a result, this third receiving apparatus  150  can send received rights information, bitstreams, and tool information to the fourth receiving apparatus  154 .  
       Sixth Embodiment  
       [0121]    [0121]FIG. 9 is a block diagram showing a receiving apparatus according to a sixth embodiment of the present invention. This embodiment of the invention relates to a fourth receiving apparatus connected to the third receiving apparatus over a home network.  
         [0122]    Referring to FIG. 9, reference numerals  111  to  114  denote the same parts as indicated by the same reference numerals in the prior art example shown in FIG. 15, reference numerals  90  to  98 ,  101  to  106 ,  108 ,  110 ,  115 ,  123  to  125 , and  132  denote the same parts referenced thereby in the third embodiment shown in FIG. 4, and reference numeral  136  is the same as in the fourth embodiment shown in FIG. 5.  
         [0123]    Also shown in FIG. 9 are fourth receiving apparatus fourth receiving apparatus  154 , fourth controller  231 , and fourth rights manager  232 .  
         [0124]    In FIG. 9 the read information  90  is separated by the demultiplexer  104  and applied to fourth controller  231 . Based on the rights information  98  and rights consumption by the fourth receiving apparatus  154 , fourth rights manager  232  generates the second reply information  136 .  
         [0125]    The playback count in this second reply information  136  is reduced by one because the video decoder  112  and digital audio signal  114  played by the fourth receiving apparatus. As a result, the rights information for program B as shown in Table 18 is rewritten as shown in Table 19.  
                               TABLE 19                                   Content   allowed   Program B                           Copying   prohibited   0X00000001           Playback count       1X00000001           Editing   prohibited   0X00000011                      
 
         [0126]    The second reply information  136  rewritten as shown in Table 19 is then sent from the fourth rights manager  232 . Operation is otherwise the same as in the third embodiment shown in FIG. 4.  
       Seventh Embodiment  
       [0127]    [0127]FIG. 10 is a block diagram showing a receiving apparatus according to a seventh embodiment of the present invention. This embodiment of the invention can download received rights information to a receiving apparatus, convert and send digital data to another receiving apparatus, and can send rights consumption information to a server.  
         [0128]    Referring to FIG. 10, reference numerals  111  to  114  denote the same parts as indicated by the same reference numerals in the prior art example shown in FIG. 15, reference numerals  90  to  98 ,  101  to  106 ,  110 ,  115 ,  123  to  125 , and  132  denote the same parts referenced thereby in the third embodiment shown in FIG. 4, and reference numeral  141  is the same as in the fourth embodiment shown in FIG. 5.  
         [0129]    Also shown in FIG. 10 are fourth rights information  1440 , fifth receiving apparatus  250 , fifth rights manager  251 , fifth controller  252 , conversion unit  253 , second encrypted video bitstream  254 , remultiplexer  255 , third MPEG-2 Systems-compliant multiplexed bitstream  256 , sixth receiving apparatus  257 , and third request information  258 .  
         [0130]    In FIG. 10 the read information  90  is separated by the demultiplexer  104  and applied to fifth controller  252 . The fifth rights manager  251  segments the rights information  98  into first rights information used by the fifth receiving apparatus  250  and fourth rights information  1440  used by sixth receiving apparatus  257 , and sends the fourth rights information  1440  to remultiplexer  255 .  
         [0131]    The fifth controller  252  is assumed to receive third request information  258  as shown in Table 20 from the sixth receiving apparatus  257 . Table 20 shows that the sixth receiving apparatus  257  sent tool and content requests to the fifth receiving apparatus  250 . The fifth controller  252  sends rights approval information to the fifth rights manager  251 , and sends first control information  141  containing a remultiplex command to the remultiplexer  255 .  
                           TABLE 20                                       Tool request   0X10000000           Content request   0X01000000                      
 
         [0132]    If the content was played once by fifth receiving apparatus  250  and once by sixth receiving apparatus  257 , the first rights information and fourth rights information  1440  are as shown in Table 21 and Table 22, respectively. The playback count is decremented by one in Table 22 because the stream was played once by fifth receiving apparatus  250 .  
                               TABLE 21                                       Copying   prohibited   0X00000000           Playback count       1X00000001           Editing   prohibited   0X00000011                      
 
         [0133]    [0133]                               TABLE 22                                       Copying   prohibited   0X00000001           Playback count       1X00000002           Editing   prohibited   0X00000011                        
         [0134]    The conversion unit  253  converts the digital video signal  111  to a compressed MPEG-4 Video-compliant (ISO/IEC 14496) stream, encrypts the compressed stream, and outputs second encrypted video bitstream  254 .  
         [0135]    The decoding tool  115  is also sent to the remultiplexer  255 . The remultiplexer  255  then remultiplexes the second encrypted video bitstream  254 , audio bitstream  126 , first control information  141 , tenth receiving apparatus  144 , and decoding tool  115  to an MPEG-2 Systems stream, and thus outputs third multiplexed bitstream  256 .  
         [0136]    The audio bitstream  106  is used in this seventh embodiment of the invention, but the digital audio signal  114  could be recompressed and used.  
         [0137]    Operation is otherwise as in the third embodiment shown in FIG. 4. As a result the fifth receiving apparatus  250  can send the received rights information, bitstream, tool information, and other data to the sixth receiving apparatus  257 .  
       Eighth Embodiment  
       [0138]    [0138]FIG. 11 is a block diagram showing a receiving apparatus according to an eighth embodiment of the present invention.  
         [0139]    Referring to FIG. 11, reference numerals  111  to  114  denote the same parts as indicated by the same reference numerals in the prior art example shown in FIG. 15, and reference numerals  90  to  96 ,  98 ,  101  to  106 ,  110 ,  115 ,  120 ,  121 ,  123  to  125 , and  132  denote the same parts referenced thereby in the third embodiment shown in FIG. 4.  
         [0140]    Also shown in FIG. 11 are reception rights information  300 , rights information receiver  301 , and seventh receiving apparatus  302 . The seventh receiving apparatus is connected to the transmission apparatus  86  shown in FIG. 3 according to the second embodiment of this invention. This eighth embodiment of the invention is similar to the third embodiment, but differs in that the rights information  98  is acquired from the reception rights information  300  instead of from the program-specific information (PSI)  92 .  
         [0141]    Referring to FIG. 11, the MPEG-2 Systems-compliant first input multiplexed bitstream  101  is first stored temporarily to the hard disk drive  102 , and is then read from storage and applied to the demultiplexer  104  as first multiplexed bitstream  103 . The demultiplexer  104  then separates this multiplexed bitstream  103  into the first encrypted video bitstream  105 , audio bitstream  106 , program-specific information  92 , and stream information  90 .  
         [0142]    The program-specific information  92  describes the relationship between the first encrypted video bitstream  105 , audio bitstream  64 , and program number of the program, and includes rights information  98  for the program, tool list  96  with the tool ID (0X00A) for AES decoding, and control graph  94  showing that the decoding tool is instantiated between the demultiplexer  104  and video decoder  112  of the receiving apparatus  302 . The read information  90  also contains key information for decrypting the first encrypted video bitstream  105 .  
         [0143]    The read information  90  is isolated by the demultiplexer  104  and applied to the first control means  120 . The program-specific information  92  is applied to the PSI demultiplexer  91 . The control graph demultiplexer  93  extracts the control graph  94  from the PSI demultiplexer  91 , and supplies it to the first control means  120 . The tool list demultiplexer  95  extracts the tool list  96  from the PSI demultiplexer  91 , and supplies it to the first control means  120 . The rights information receiver  301  receives the reception rights information  300 , and extracts and outputs the rights information  98  to the first rights manager  121 .  
         [0144]    The first control means  120  sends first request information  137  as shown in Table 23. As shown in the table, a tool and content (program) request are sent.  
                           TABLE 23                                       Tool request   0X10000000           Content request   0X01000000                      
 
         [0145]    The first control means  120  knows from the tool list  96  that decoding tool  115  is the tool needed for decryption, knows from the control graph  94  that the control point for applying the decoding tool  115  is  108 , and extracts the descrambling key from the read information  90 .  
         [0146]    The first control means  120  sends a command for instantiating the decoding tool  115  and key information extracted from the stream information  118  to the instantiating means  108  according to the control graph  94 , which indicates that the decoding tool  115  is instantiated between the demultiplexer  104  and video decoder  112  of the seventh receiving apparatus  302 . The instantiating means  108  then embeds the decoding tool  115  and key information. The first encrypted video bitstream  105  is then decrypted by the instantiating means  108 , and output as video bitstream  110 .  
         [0147]    The video bitstream  110  is then decompressed by the video decoder  112  and output as digital video signal  111 . The audio bitstream  106  is expanded by the audio decoder  113 , and output as digital audio signal  114 .  
         [0148]    The first rights manager  121  acquires the rights information  98 , and outputs file management information  123  to the file manager  124 . Because the playback count assigned with the value shown in Table 4 is only once with program A, the file manager  124  sends a hard disk drive control command  125  to the hard disk drive  102  to erase the stored program A once the program has been read once.  
         [0149]    The first rights manager  121  sends the information shown in Table 24 as the first reply information  132 . This reply shows that the program has been played once by the seventh receiving apparatus  302 .  
                           TABLE 24                                       No. times played by 7th receiver   0X00000001                      
 
       Ninth Embodiment  
       [0150]    [0150]FIG. 12 is a block diagram showing a receiving apparatus according to a ninth embodiment of the present invention. This ninth embodiment of the invention can download received rights information to a receiving apparatus connected to a network, transfer digital data, and send rights consumption information to a server.  
         [0151]    Referring to FIG. 12, reference numerals  111  to  114  denote the same parts as indicated by the same reference numerals in the prior art example shown in FIG. 15, reference numerals  90  to  96 ,  98 ,  101  to  106 ,  110 ,  115 ,  123  to  125 , and  132  denote the same parts referenced thereby in the third embodiment, reference numerals  133 ,  136 ,  138  to  143  denote the same parts referenced thereby in the fourth embodiment, and reference numerals  300  and  301  denote the same parts referenced thereby in the eighth embodiment.  
         [0152]    Also shown in the figure are an eighth receiving apparatus  310  and eleventh receiving apparatus  145 .  
         [0153]    This eighth receiving apparatus  310  is assumed to be connected to the second transmission apparatus according to the present invention shown in FIG. 3, and the eleventh receiving apparatus  145  has the same functions as the first receiving apparatus shown in FIG. 4.  
         [0154]    Referring to FIG. 12, the control graph demultiplexer  93  extracts the control graph  94  from the PSI demultiplexer  91 , and supplies it to the second control means  139 . The tool list demultiplexer  95  extracts the tool list  96  from the PSI demultiplexer  91 , and supplies it to the second control means  139 . The rights information receiver  301  receives the reception rights information  300  and extracts the rights information  98 , which it then outputs to the second rights manager  138 .  
         [0155]    The second control means  139  receives second request information  140  as shown in Table 25 from the eleventh receiving apparatus  145 . Table 25 shows that the eleventh receiving apparatus  145  sent tool and content requests to the second receiving apparatus  130 .  
                           TABLE 25                                       Tool request   0X10000000           Content request   0X01000000                      
 
         [0156]    The read information  90  is demultiplexed by the demultiplexer  104  and applied to the second control means  139 . The second rights manager  138  separates the rights information  98  into the first rights information used by the second receiving apparatus  130  and the second rights information  133  used by the eleventh receiving apparatus  145 , and based on the first rights information sends file management information  123  to the file manager  124 . A rights approval command is sent to the second rights manager  138 , and first control information  141  including correction of the first multiplexed bitstream  103  is sent to the multiplexing adjustment means  142 .  
         [0157]    If the eighth receiving apparatus  310  plays program B with rights information shown in Table 4 once and sends program B to eleventh receiving apparatus  145 , the first rights information is as shown in Table 26 and second rights information  133  is as shown in Table 27. Note that the playback count is reduced by one in Table 27 showing the second rights information sent to the eleventh receiving apparatus  145  because program B was played once by second receiving apparatus  130 .  
                               TABLE 26                                       Copying   prohibited   0X00000000           Playback count       1X00000001           Editing   prohibited   0X00000011                      
 
         [0158]    [0158]                               TABLE 27                                       Copying   prohibited   0X00000001           Playback count       1X00000002           Editing   prohibited   0X00000011                        
         [0159]    The second rights manager  138  sends the second rights information  133  shown in Table 14 to the multiplexing adjustment means  142 . The multiplexing adjustment means  142  then modifies the first multiplexed bitstream  103  based on the second rights information  133 . That is, the rights information  122  of first multiplexed bitstream  103  is changed to the content of second rights information  133  to output second multiplexed bitstream  143 .  
         [0160]    Other operations are as described in the fourth embodiment. As a result the second receiving apparatus  130  can send the received rights information, bitstream, and tool information to the eleventh receiving apparatus  145  connected over a network.  
         [0161]    The second rights manager  138  outputs first reply information  132  based on the second reply information from the eleventh receiving apparatus  145 . If the eighth receiving apparatus  310  and eleventh receiving apparatus  145  each played the stream once, the first reply information is output as shown in Table 28.  
                           TABLE 28                                       No. times played by 2nd receiver   0X00000001           No. times played by 10th receiver   0X00000001                      
 
         [0162]    The transmission apparatus according to this embodiment of the invention can thus acquire consumption information from the eighth receiving apparatus  310  and a eleventh receiving apparatus  145  connected to the eighth receiving apparatus  310 .  
       Tenth Embodiment  
       [0163]    [0163]FIG. 13 is a block diagram showing a receiving apparatus according to a tenth embodiment of the present invention. This tenth embodiment of the invention relates to a separate receiving apparatus connected to another receiving apparatus over a home network.  
         [0164]    Referring to FIG. 13, reference numerals  111  to  114  denote the same parts as indicated by the same reference numerals in the prior art example shown in FIG. 15, reference numerals  90  to  96 ,  98 ,  101  to  106 ,  110 ,  115 ,  123  to  125 , and  132  denote the same parts referenced thereby in the third embodiment shown in FIG. 4, reference numerals  136  and  140  are the same as in the fourth embodiment shown in FIG. 5, reference numerals  153 ,  154 ,  160 , and  161  denote the same parts referenced thereby in the fifth embodiment shown in FIG. 8, and reference numerals  300  and  301  denote the same parts referenced thereby in the eighth embodiment shown in FIG. 11.  
         [0165]    Also shown in FIG. 11 is a ninth receiving apparatus  320 .  
         [0166]    Referring to FIG. 13, the control graph demultiplexer  93  extracts the control graph  94  from the PSI demultiplexer  91 , and supplies it to the third controller  160 . The tool list demultiplexer  95  extracts the tool list  96  from the PSI demultiplexer  91 , and supplies it to the third controller  160 . The rights information receiver  301  receives the reception rights information  300 , and extracts and outputs the rights information  98  to the third rights manager  161 .  
         [0167]    The read information  90  is applied to the third controller  160 . The third rights manager  161  separates the rights information  98  into the first rights information used by ninth receiving apparatus  320  and third rights information  153  used by fourth receiving apparatus  154 , and sends the third rights information  153  to fourth receiving apparatus  154 .  
         [0168]    The third controller  160  receives the second request information  140  shown in Table 28 from fourth receiving apparatus  154 . Table 29 shows that the fourth receiving apparatus  154  sent tool and content requests to the ninth receiving apparatus  320 . The third controller  160  sends rights approval information to the third rights manager  161 .  
                           TABLE 29                                       Tool request   0X10000000           Content request   0X01000000                      
 
         [0169]    If the content was played once by ninth receiving apparatus  320  and once by fourth receiving apparatus  154 , the first rights information and third rights information  153  will be as shown in Table 30 and Table 31, respectively. The playback count is decremented one in Table 31 because the content was played once by ninth receiving apparatus  320 .  
                               TABLE 30                                       Copying   prohibited   0X00000000           Playback count       1X00000001           Editing   prohibited   0X00000011                      
 
         [0170]    [0170]                               TABLE 31                                       Copying   prohibited   0X00000001           Playback count       1X00000002           Editing   prohibited   0X00000011                        
         [0171]    Other operations are the same as described in the fifth embodiment. As a result this ninth receiving apparatus  320  can send the received rights information, bitstream, and tool information to the fourth receiving apparatus  154 .  
       Eleventh Embodiment  
       [0172]    [0172]FIG. 14 is a block diagram showing a receiving apparatus according to an eleventh embodiment of the present invention. This eleventh embodiment of the invention relates to a first transmission apparatus  73 , second receiving apparatus  130 , and tenth receiving apparatus  144  connected by a network to the second receiving apparatus.  
         [0173]    Referring to FIG. 14, reference numerals  49  and  50  denote the same parts as indicated by the same reference numerals in the prior art example shown in FIG. 15, reference numerals  66 ,  73 , and  74  denote the same parts referenced thereby in the first embodiment, and reference numerals  111 ,  114 ,  130 ,  136 ,  140 ,  143 , and  144  denote the same parts referenced thereby in the fourth embodiment shown in FIG. 5.  
         [0174]    Referring to FIG. 14, the tenth receiving apparatus  144  outputs second request information  140  to second receiving apparatus  130 .  
         [0175]    The second receiving apparatus  130  outputs status information  74  to first transmission apparatus  73 .  
         [0176]    The first transmission apparatus  73  outputs a first multiplexed bitstream  66  as in the first embodiment above.  
         [0177]    The first multiplexed bitstream  66  received by the second receiving apparatus  130  is labelled  101  in the fourth embodiment, is processed the same as in the fourth embodiment to output digital video signal  111  and digital audio signal  114 , and is output as second multiplexed bitstream  143  to tenth receiving apparatus  144 .  
         [0178]    The tenth receiving apparatus  144  operates the same as in the third embodiment of this invention, and outputs second reply information  136 .  
       EFFECTS OF THE INVENTION  
       [0179]    As will be obvious from the above descriptions, the present invention can download encrypted data, a tool list and tool for decrypting the encrypted data, the location where the tool is instantiated, key information, and rights information to a receiving apparatus as part of the multiplexed data. Our invention can therefore provide a highly reliable transmission apparatus that can always provide the latest protection for digital content.  
         [0180]    This invention also provides the advantage of being able to process the encrypted data, a tool list and tool for decrypting the encrypted data, the location where the tool is instantiated, key information, and rights information as part of the program-specific information of the multiplexed data.  
         [0181]    This invention can also send the rights information as a file separate from the multiplexed data. Because the rights information can thus be handled separately from the multiplexed data, a convenient transmission apparatus that does not need to remultiplex the content stream when the receiving apparatus rewrites the rights information for transfer to another receiving apparatus can be provided.  
         [0182]    This invention can also send the rights information as a file separate from the multiplexed data while also specifically correlating the rights information to the multiplexed data. A convenient transmission apparatus that can correctly associate multiple multiplexed data streams with the corresponding rights information can therefore be provided.  
         [0183]    Yet further, this invention can also provide a convenient transmission apparatus that can multiplex and send the decoding tool for decrypting the encrypted content stream together with the content stream.  
         [0184]    Yet further, this invention can also provide a convenient transmission apparatus that can multiplex and send key information for decrypting the encrypted content stream together with the content stream.  
         [0185]    The present invention can also provide a high reliability receiving apparatus that can download and therefore update encrypted data, a tool list and tool for decrypting the encrypted data, the location where the tool is instantiated, key information, and rights information as part of the multiplexed data. As a result, the receiving apparatus of our invention can always provide the latest protection for digital content.  
         [0186]    Furthermore, because the present invention can download encrypted data, a tool list and tool for decrypting the encrypted data, the location where the tool is instantiated, key information, and rights information, this information can be updated and the latest protection for digital content can always be provided. Even more conveniently, this information can be processed as part of the program-specific information of the multiplexed data.  
         [0187]    Furthermore, because the present invention can download encrypted data, a tool list and tool for decrypting the encrypted data, the location where the tool is instantiated, key information, and rights information, this information can be updated and the latest protection for digital content can always be provided. In addition, because the rights information can be sent as a separate file from the multiplexed data, a receiving apparatus with the convenience of being able to handle rights information separately from the multiplexed data, and the option of sending the rights information to another receiving apparatus, can be provided.  
         [0188]    Furthermore, because the present invention can download encrypted data, a tool list and tool for decrypting the encrypted data, the location where the tool is instantiated, key information, and rights information, this information can be updated and the latest protection for digital content can always be provided. In addition, because received encrypted data can be deleted based on the rights information, a high reliability receiving apparatus that does not leave used content on the receiving apparatus and can prevent unauthorized use can be provided.  
         [0189]    Furthermore, because the present invention can download encrypted data, a tool list and tool for decrypting the encrypted data, the location where the tool is instantiated, key information, and rights information, this information can be updated and the latest protection for digital content can always be provided. In addition, the receiving apparatus can send consumption information about received encrypted data to the transmission apparatus, and can provide information about content consumption by the receiving apparatus.  
         [0190]    Furthermore, because the present invention can download to a different receiving apparatus encrypted data, a tool list and tool for decrypting the encrypted data, the location where the tool is instantiated, key information, and rights information, this information can be updated and the latest protection for digital content can always be provided. In addition, the receiving apparatus can send to the transmission apparatus consumption information about encrypted data received by a different receiving apparatus, and can provide information about content consumption by the receiving apparatus.  
         [0191]    Furthermore, because the present invention can download encrypted data, a tool list and tool for decrypting the encrypted data, the location where the tool is instantiated, key information, and rights information, this information can be updated and the latest protection for digital content can always be provided. In addition, the received rights information can be separated and sent with the encrypted data to another receiving apparatus. As a result, the other receiving apparatus can also process the encrypted data with the same high reliability.  
         [0192]    Furthermore, because the present invention can download encrypted data, a tool list and tool for decrypting the encrypted data, the location where the tool is instantiated, key information, and rights information, this information can be updated and the latest protection for digital content can always be provided. In addition, by converting the received data, the receiving apparatus can transfer it as a signal optimized for another receiving apparatus.  
         [0193]    Although the present invention has been described in connection with the preferred embodiments thereof with reference to the accompanying drawings, it is to be noted that various changes and modifications will be apparent to those skilled in the art. Such changes and modifications are to be understood as included within the scope of the present invention as defined by the appended claims, unless they depart therefrom.  
         [0194]    The present disclosure relates to subject matter contained in priority Japanese Patent Application No. 2002-210727, filed on Jul. 19, 2002, the contents of which is herein expressly incorporated by reference in its entirety.