Abstract:
When digital contents sold to a user become useless to the user, the digital contents and the license of the digital contents are collected or purchased from the user so that a privilege such as discount sale of other digital contents or addition of discount points is granted to the user having the license.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     The present invention relates to a system for collecting or purchasing unnecessary digital contents and licenses thereof from users.  
         [0003]     2. Description of the Related Art  
         [0004]     With the development of communications on the Internet, portable information terminals, etc., distribution and sale of digital contents using these terminals and networks have been activated. A technique for performing distribution and sale of digital contents has been described in JP-A-11-224288.  
       SUMMARY OF THE INVENTION  
       [0005]     In digital contents distributing business, there was however a problem that it was difficult to purchase or collect contents from users because the contents were not delivered through a general physical distribution system. Therefore, a method of collecting unnecessary digital contents from users to thereby make it easier for the users to purchase new digital contents has been demanded.  
         [0006]     An object of the invention is to provide a digital contents management method in which unnecessary digital contents can be returned easily.  
         [0007]     To achieve the foregoing object, in accordance with the invention, when a user issues a license return request to return a license granted for digital contents already purchased by the user, the license corresponding to the license return request is deleted; the user corresponding to the deleted license is specified; and management is made so that the specified user is associated with contents of the deleted license or with a privilege granted in accordance with the license return request. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0008]      FIG. 1  is a diagram showing the system configuration of a digital contents license and incentive point management system according to an embodiment of the invention;  
         [0009]      FIG. 2  is a diagram showing the configuration of a digital contents management device  110 ;  
         [0010]      FIG. 3  is a diagram showing the configuration of a license management device  120 ;  
         [0011]      FIG. 4  is a diagram showing the configuration of a digital contents storage device  130 ;  
         [0012]      FIG. 5  is a diagram showing the configuration of a digital contents synchronization device  140 ;  
         [0013]      FIG. 6  is a diagram showing the configuration of a terminal unit  150 ;  
         [0014]      FIG. 7  is a flow chart showing a processing procedure in a contents setup method;  
         [0015]      FIG. 8  is a flow chart showing a processing procedure in a contents collection/purchase method;  
         [0016]      FIG. 9  is a flow chart showing a processing procedure in an individual contents download method;  
         [0017]      FIG. 10  is a flow chart showing a processing procedure in a batch contents download method;  
         [0018]      FIG. 11  is a view showing a user-based license transfer management table for managing the number of licenses collected from each user, the number of licenses purchased from each user and the number of incentive points given to each user;  
         [0019]      FIG. 12  is a view showing a transaction management table for managing processing concerning sale, collection and purchase of contents; and  
         [0020]      FIG. 13  is a view showing a merchandise management table for indicating licenses and selling prices of contents. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0021]     A preferred embodiment of the invention will be described below in detail with reference to the drawings but the invention is not limited thereto.  
         [0022]     A system for managing licenses of digital contents and privileges (e.g., points that can be used for purchase of digital contents) corresponding to return of licenses in digital contents sale where the licenses of the digital contents can be returned (specifically, collected or purchased) from users will be described as an embodiment of the invention. Digital contents may be hereinafter also referred to as contents.  
         [0023]      FIG. 1  is a diagram showing the schematic configuration of a digital contents license and incentive point management system according to this embodiment. As shown in  FIG. 1 , this system includes a contents management device  110 , a license management device  120 , a contents storage device  130 , a contents synchronization device  140 , and terminal units  150 .  
         [0024]     Although the license and incentive point management system includes the contents synchronization device  140  provided for the sake of user&#39;s convenience, each user can select contents one by one and download the contents one by one to the user&#39;s terminal unit not via the contents synchronization device  140 . On the other hand, the user can make batch contents download via the contents synchronization device  140 .  
         [0025]     The contents management device  110  is provided for sale, collection and purchase of contents. The contents management device  110  manages contents received in trust from a contents holder or the like. The contents management device  110  performs a process for granting and regenerating licenses. Incidentally, license management is performed by the license management device  120 .  
         [0026]     The license management device  120  manages licenses generated when contents managed by the contents management device  110  are sold to users. Respective processing portions in the license management device  120  may be placed in the contents management device  110  and the contents storage device  130  for the sake of reduction in cost. The separate provision of the license management device  120  permits the license management device  120  to be used for cooperative management of licenses on the basis of business tie-up when a contents sale site  100  having the contents management device  110  and a contents archive site  160  having the contents storage device  130  are business sites independent of each other.  
         [0027]     The contents storage device  130  stores contents purchased by users and stores contents requested to be downloaded by users.  
         [0028]     The contents synchronization device  140  collects contents from the contents management device  110  and performs batch contents download to a terminal unit  150  when a user wants to download selected contents by batch processing. On this occasion, the contents synchronization device  140  cooperates with the terminal unit  150  to monitor whether all the contents selected by the user are downloaded or not.  
         [0029]     The terminal unit  150  (user terminal) is a terminal used by each user. Examples of the terminal unit  150  include all apparatuses each of which can serve as a terminal unit, such as a personal computer (PC), a personal digital assistant (PDA), a tablet PC, etc. The terminal unit  150  can be also used in an off-line mode.  
         [0030]      FIG. 2  is a diagram showing the configuration of the contents management device  110  depicted in  FIG. 1 . As shown in  FIG. 2 , the contents management device  110  has a CPU  210 , a memory  220 , a data recording device  230 , an input device  240  (such as a keyboard), a display  250  as a display device, and a communication adapter  260 .  
         [0031]     The CPU  210  is a controller for controlling the operation of the contents management device  110  as a whole. The memory  220  is a recoding device loaded with data and various kinds of processing programs for controlling the operation of the contents management device  110 . The data recording device  230  is a recording device for storing the various kinds of processing programs and various kinds of digital contents. The input device  240  (such as a keyboard) is an input device for inputting operation instructions or the like to the contents management device  110 . The communication adapter  260  is an adapter for communication with other devices.  
         [0032]     The memory  220  in the contents management device  110  has a contents management processing portion  221 , a license management processing portion  222 , a user management processing portion  223 , a contents account processing portion  224 , and a contents setup processing portion  225 .  
         [0033]     The contents management processing portion  221  performs sale processing at the time of selling contents to a user, collection processing at the time of user&#39;s issuing a request to collect contents from the user, and purchase processing at the time of user&#39;s issuing a request to purchase contents from the user and stores processing results in a contents management DB  231 . The license management processing portion  222  performs processing for granting licenses for contents respectively and processing for deleting a license from a user&#39;s contents list at the time of collection/purchase of the license. The license management processing portion  222  stores processing results in a license management DB  232 .  
         [0034]     The user management processing portion  223  manages incentive points etc. as well as information concerning sale to users, and collection and purchase from users, and exchanges data with a user management DB  233 . The contents account processing portion  224  performs account processing at the time of sale of contents and is linked to an external settlement system. The contents setup processing portion  225  performs processing for setting up contents in the contents storage device  130  so that contents purchased by the user can be downloaded at any time.  
         [0035]     The contents management DB  231  in the data recording device  230  manages information concerning sale, collection and purchase of contents processed by the contents management processing portion  221 . The license management DB  232  manages contents license information processed by the license management processing portion  222 . The user management DB  233  manages information concerning contents sale for each individual user (as a history of sale to the user and purchase from the user) processed by the user management processing portion  223 .  
         [0036]     A program for making the contents management device  110  function as each of the contents management processing portion  221 , the license management processing portion  222 , the user management processing portion  223 , the contents account processing portion  224  and the contents setup processing portion  225  is recorded in a recording medium such as a CD-ROM, stored in the recording device such as a magnetic disk and then loaded into the memory so that the program can be executed. Incidentally, the medium used for recording the program may be another recording medium such as a DVD or a DAT than the CD-ROM.  
         [0037]      FIG. 3  is a diagram showing the configuration of the license management device  120  depicted in  FIG. 1 . As shown in  FIG. 3 , the license management device  120  has a CPU  310 , a memory  320 , a data recording device  330 , an input device  340  such as a keyboard, a display  350 , and a communication adapter  360 .  
         [0038]     The CPU  310  is a controller for controlling the operation of the license management device  120  as a whole. The memory  320  is a recording device loaded with data and various kinds of processing programs for controlling the operation of the license management device  120 . The data recording device  330  is a recording device for storing the various kinds of processing programs and various kinds of digital contents. The input device  340  is an input device for inputting operation instructions or the like to the license management device  120 . The communication adapter  360  is an adapter for communication with other devices.  
         [0039]     The memory  320  in the license management device  120  has a user-based license management processing portion  321 . The user-based license management processing portion  321  manages a list of contents held by each user and licenses of the contents in a user-based license management DB  331 . When the contents storage device  130  requests the user-based license management processing portion  321  to collate contents in accordance with each user, the user-based license management processing portion  321  performs processing for retrieving contents in accordance with each user from the user-based license management DB  331  and replying to the contents storage device  130  by the license result.  
         [0040]     The user-based license management DB  331  in the data recording device  330  manages contents license information in accordance with each user.  
         [0041]     A program for making the license management device  120  function as the user-based license management processing portion  321  is recorded in a recording medium such as a CD-ROM, stored in the recording device such as a magnetic disk and then loaded into the memory so that the program can be executed. Incidentally, the medium used for recording the program may be another recording medium such as a DVD or a DAT than the CD-ROM.  
         [0042]      FIG. 4  is a diagram showing the configuration of the contents storage device  130  depicted in  FIG. 1 . As shown in  FIG. 4 , the contents storage device  130  has a CPU  410 , a memory  420 , a data recording device  430 , an input device  440  such as a keyboard, a display  450 , and a communication adapter  460 .  
         [0043]     The CPU  410  is a controller for controlling the operation of the contents storage device  130  as a whole. The memory  420  is a recording device loaded with data and various kinds of processing programs for controlling the operation of the contents storage device  130 . The data recording device  430  is a recording device for storing the various kinds of processing programs and various kinds of digital contents. The input device  440  is an input device for inputting operation instructions or the like to the contents storage device  130 . The communication adapter  460  is an adapter for communication with other devices.  
         [0044]     The memory  420  in the contents storage device  130  has a contents storage processing portion  421 , a license management processing portion  422 , a use-restricted contents generation processing portion  423 , and a user management processing portion  424 .  
         [0045]     The contents storage processing portion  421  performs processing in accordance with a contents setup request or a contents deletion request given from the contents management device  110  in accordance with each user. The contents storage processing portion  421  performs processing so that contents sent from the contents management device  110  in accordance with each user are stored in a contents storage DB  431  in the data recording device  430 . Similarly, license information and user information of contents sent from the contents management device  110  are managed by a license management DB  432  and a user management DB  433  respectively in the data recording device  430 .  
         [0046]     The license management processing portion  422  manages licenses of contents processed by the contents storage processing portion  421 . The license management processing portion  422  collates licenses for the license management device  120  in accordance with each user and sends collation results to the contents storage processing portion  421 .  
         [0047]     The use-restricted contents generation processing portion  423  acquires contents held by a user from the contents storage DB  431  and generates restricted contents with an audiovisual and playback time limit when the contents storage processing portion  421  receives a download request from the user.  
         [0048]     The user management processing portion  424  manages owners (users) of contents managed in the contents storage device  130  and processes information concerning user individuals such as user customization information, user private information so that these pieces of information are managed in the user management DB  433 . The user management processing portion  424  performs processing such as user authentication by using these pieces of information. The user management processing portion  424  identifies each user and contents held by the user by using the user ID of the user and the contents ID of the contents.  
         [0049]     The contents storage DB  431  manages contents in accordance with each user and attribute information of the contents. These pieces of information are sent to the use-restricted contents generation processing portion  423  and finally sent to the terminal unit  150  in accordance with an instruction given from the contents storage processing portion  421 .  
         [0050]     A program for making the contents storage device  130  function as each of the contents storage processing portion  421 , the license management processing portion  422 , the use-restricted contents generation processing portion  423  and the user management processing portion  424  is recorded in a recording medium such as a CD-ROM, stored in the recording device such as a magnetic disk and then loaded into the memory so that the program can be executed. Incidentally, the medium used for recording the program may be another recording medium such as a DVD or a DAT than the CD-ROM.  
         [0051]      FIG. 5  is a diagram showing the configuration of the contents synchronization device  140  depicted in  FIG. 1 . As shown in  FIG. 5 , the contents synchronization device  140  has a CPU  510 , a memory  520 , a data recording device  530 , an input device  540 , a display  550 , and a communication adapter  560 .  
         [0052]     The CPU  510  is a controller for controlling the operation of the contents synchronization device  140  as a whole. The memory  520  is a recording device loaded with data and various kinds of processing programs for controlling the operation of the contents synchronization device  140 . The data recording device  530  is a recording device for storing the various kinds of processing programs and various kinds of digital contents. The input device  540  is an input device for inputting operation instructions or the like to the contents synchronization device  140 . The communication adapter  560  is an adapter for communication with other devices.  
         [0053]     The memory  520  in the contents synchronization device  140  has a contents management processing portion  521 , a user management processing portion  522 , and a contents synchronization processing portion  523 .  
         [0054]     The contents management processing portion  521  selects contents to be batch-downloaded to the terminal unit  150  from contents held by each user and acquires the contents from the contents storage device  130  to make preparations for download of the contents to the user&#39;s terminal unit  150 .  
         [0055]     The user management processing portion  522  manages customization information such as a list of contents to be synchronized in accordance with each user and private information. The private information is stored as user management information in a user management DB  532 .  
         [0056]     The contents synchronization processing portion  523  performs processing so that all the contents prepared by the contents management processing portion  521  are sent to the terminal unit  150  while the contents list selected by the user and managed in the contents synchronization device  140  is synchronized with a contents list managed in the terminal unit  150 .  
         [0057]     A program for making the contents synchronization device  140  function as each of the contents management processing portion  521 , the user management processing portion  522  and the contents synchronization processing portion  523  is recorded in a recording medium such as a CD-ROM, stored in the recording device such as a magnetic disk and then loaded into the memory so that the program can be executed. Incidentally, the medium used for recording the program may be another recording medium such as a DVD or a DAT than the CD-ROM.  
         [0058]      FIG. 6  is a diagram showing the configuration of the terminal unit  150  depicted in  FIG. 1 . As shown in  FIG. 6 , the terminal unit  150  has a CPU  610 , a memory  620 , a data recording medium or data recording device  630  such as a hard disk, an input device  640  such as an operation button, a display device  650  such as a display, and a communication adapter  660 .  
         [0059]     The CPU  610  is a controller for controlling the operation of the terminal unit  150  as a whole. The memory  620  is a recording device loaded with data and various kinds of processing programs for controlling the operation of the terminal unit  150 . The data recording device  630  is a recording device for storing the various kinds of processing programs and various kinds of digital contents. The input device  640  is an input device for inputting operation instructions or the like to the terminal unit  150 . The communication adapter  660  is an adapter for communication with other devices.  
         [0060]     The memory  620  in the terminal unit  150  has a contents management processing portion  621 , an audiovisual processing portion  622 , a user management processing portion  623 , and a contents synchronization processing portion  624 .  
         [0061]     The contents management processing portion  621  acquires contents from the contents storage device  130  and stores contents license information  631  and contents body and attribute information  632  in the data recording device  630 . The audiovisual processing portion  622  performs processing for displaying user management information  633  and the contents body and attribute information  632  stored in the data recording medium or device  630  of the terminal unit  150  on the display  650  and also performs processing for displaying user operation results in the terminal unit  150  such as display of a setting screen on the display  650 .  
         [0062]     The user management processing portion  623  manages customization information such as a contents display method and private information in the terminal unit  150 . The private information is stored as user management information  633  in the data recording device  630 . The contents synchronization processing portion  624  acquires contents from the contents synchronization device  140  by batch processing and stores the contents license information  631  and the contents body and attribute information  632  in the data recording medium or device  630 .  
         [0063]     A program for making the terminal unit  150  function as each of the contents management processing portion  621 , the audiovisual processing portion  622 , the user management processing portion  623  and the contents synchronization processing portion  624  is recorded in a recording medium such as a CD-ROM, stored in the recording device such as a magnetic disk and then loaded into the memory so that the program can be executed. Incidentally, the medium used for recording the program may be another recording medium such as a DVD or a DAT than the CD-ROM.  
         [0064]      FIG. 7  is a flow chart showing a processing procedure in a method for setting up contents in the contents storage device  130  at the time of user&#39;s purchase of contents in the system having the contents management device  110 , the license management device  120 , the contents storage device  130  and the terminal units  150  according to this embodiment.  
         [0065]     First, the contents management processing portion  621  of each terminal unit  150  sends a contents purchase request to the contents management device  110  (step  700 ). Contents designated by the request are specified on the basis of contents identification information. The contents management processing portion  221  of the contents management device  110  acquires merchandise information of the contents from merchandise management table data  1300  by using the contents identification information sent in the step  700  (step  701 ). The acquired merchandise information includes selling prices, etc. In the step  701 , an account processing request is given to the contents account processing portion  224  in concurrence with the processing for acquiring merchandise information of the contents. Unless the contents account processing portion  224  completes the contents account processing for the user wanting to purchase the contents, the current position of the procedure does not go to the next step. When the contents account processing succeeds, the current position of the procedure goes to step  702 . Incidentally, whether cash account or credit account is used can be decided according to a business method of each businessman.  
         [0066]     Then, the license management device  120  performs processing for registering the license of the contents requested by the contents management device  110  (step  702 ). That is, in the step  702 , the license management device  120  acquires numbers such as a user ID and a contents ID from the contents management device  110  and registers the license of the contents requested to be purchased in the step  701 , in the user-based license management DB  331  of the license management device  120 . The result of the license registration processing in the step  702  is sent to the contents management device  110  (step  703 ). On this occasion, the license is registered if the registration processing succeeds, but the license is not registered if the registration processing fails.  
         [0067]     Then, the contents management device  110  makes a judgment on the basis of the license registration result as reply processing in the step  703  as to whether the license registration succeeds or not (step  704 ). When the license registration succeeds, the contents management device  110  gives a contents setup request to the contents storage device  130  (step  705 ). On the other hand, when the license registration fails, the contents are not registered and a notice of the failure in the license registration is sent to the terminal unit (step  714 ).  
         [0068]     Then, the contents storage device  130  requests the license management device  120  to collate the license as to whether the user purchasing the contents is licensed to use the contents requested to be set up by the contents management device  110  or not (step  706 ). The license management device  120  collates the license in accordance with the license collation request (step  707 ) and replies by the collation result to the contents storage device  130  (step  708 ).  
         [0069]     Then, the contents storage device  130  makes a judgment on the basis of the collation result sent back from the license management device  120  as to whether collation succeeds or not, that is, whether the user purchasing the contents is licensed to use the contents requested to be set up or not (step  709 ). When collation succeeds, contents setup processing is performed (step  710 ). When collation fails, information indicating the failure in collation and incompletion of the contents setup processing is sent back to the contents management device  110  (step  711 ). Although the current position of the procedure goes to the step  711  regardless of whether collation succeeds or not, information sent back to the contents management device  110  in the step  711  varies according to the collation result.  
         [0070]     The contents management device  110  makes a judgment on the basis of the contents setup result sent back from the contents storage device  130  as to whether the contents are set up or not (step  712 ). When the contents are set up, the contents management device  110  registers the contents (step  713 ). If a decision is made in the step  712  that the contents are not registered, it is necessary to invalidate the account processing carried out in the step  701 . Accordingly, not use of cash account processing but use of credit account processing in the step  701  is efficient.  
         [0071]     Then, the contents management device  110  sends a registration status indicating whether the contents are registered or not, back to the terminal unit  150 . The terminal unit  150  performs contents purchase result processing on the basis of the result sent back (step  715 ).  
         [0072]      FIG. 8  is a flow chart showing a procedure in contents deletion processing of the contents storage device  130  at the time of collection or purchase of contents from a user, in the system having the contents management device  110 , the license management device  120 , the contents storage device  130  and the terminal units  150 .  
         [0073]     First, the contents management processing portion  621  of each terminal unit  150  sends a request of purchase/collection of contents held by the user, to the contents management processing portion  221  of the contents management device  110  (step  800 ). The contents are specified on the basis of contents identification information. Then, the contents management processing portion  221  of the contents management device  110  acquires attribute information of contents held by the user from the contents management DB  231  and the license management DB  232  by using the contents identification information sent from the terminal unit  150  in the step  800  (step  801 ). When the user and the contents are verified, the current position of the procedure goes to step  802 .  
         [0074]     Then, the license management device  120  performs license deletion processing for the contents requested by the contents management device  110  (step  802 ). That is, on this occasion, the license management device  120  acquires numbers such as a user ID and a contents ID from the contents management device  110  and deletes the license of the contents from the user-based license management DB  331  of the license management device  120 . The result of the deletion processing is sent back to the contents management device  110  (step  803 ). The contents management device  110  makes a judgment on the basis of the sent deletion result as to whether the deletion processing succeeds or not (step  804 ). When the license deletion processing succeeds, the contents management device  110  sends a contents deletion request to the contents storage device  130  (step  805 ). When the license deletion processing fails, the license is not deleted but a contents status indicating the failure in the deletion processing is sent back to the terminal unit  150  (step  810 ).  
         [0075]     When a decision is made in the step  804  that the license deletion processing succeeds, the contents management device  110  requests the contents storage device  130  to delete contents corresponding to the license deleted by the license management device  120  (step  805 ). The contents storage processing portion  421  of the contents storage device  130  deletes the contents in accordance with the contents deletion request received (step  806 ). When the contents deletion processing fails, the deletion processing is repeated by a predetermined number of times. This is because repetition of the deletion processing till success causes instability of the system.  
         [0076]     The contents storage device  130  sends a result of the contents deletion processing in the step  806  back to the contents management device  110  (step  807 ).  
         [0077]     The contents management device  110  performs incentive point addition/contents version upgrade processing for the user issuing the contents purchase/collection request, on the basis of the result sent back from the contents storage device  130  (step  809 ). On this occasion, when the license deletion fails, incentive point addition processing is not performed. Incidentally, the incentive points may be given to the user so that the user can purchase digital contents for the added incentive points but the digital contents purchased for the incentive points cannot be sold but can be collected from the user. The contents version upgrade processing is a processing in which the version of contents can be upgraded at a special price lower than the ordinary price.  
         [0078]     Then, the contents management device  110  sends a current contents status back to the terminal unit  150  (step  810 ). The terminal unit  150  performs processing for displaying the result of collection/purchase of the contents requested by the user and storing information concerning collection/purchase of the contents on the basis of the result sent back (step  811 ).  
         [0079]      FIG. 9  is a flow chart showing a processing procedure in an individual contents download method used in the system having the license management device  120 , the contents storage device  130  and the terminal units  150 .  
         [0080]     First, the contents management processing portion  621  of each terminal unit  150  sends a request to the contents storage device  130  to download contents from the contents storage device  130  (step  900 ). Then, the contents storage processing portion  421  of the contents storage device  130  retrieves the designated contents stored in the contents storage DB  431  of the contents storage device  130  on the basis of contents identification information sent in the step  900  (step  901 ) and judges whether the contents are stored in the contents storage DB  431  of the contents storage device or not (step  902 ).  
         [0081]     When a decision is made that the contents are stored in the contents storage DB  431 , the contents storage device  130  sends a request to the license management device  120  to collate the license (step  903 ). Incidentally, license collation in the step  903  may be performed in the contents storage device  130  if the contents storage device  130  can perform the same processing as the license management device  120 .  
         [0082]     The license management device  120  collates the license in accordance with the license collation request issued in the step  903  (step  904 ). A result of collation is sent back to the contents storage device  130  (step  905 ).  
         [0083]     The contents storage device  130  makes a judgment on the basis of the license collation result sent back from the license management device  120  as to whether collation succeeds or not (step  906 ). When collation succeeds, the use-restricted contents generation processing portion  423  of the contents storage device  130  generates use-restricted contents (step  907 ). When collation fails, information indicating failure in collation and incompletion of contents setup is sent back to the terminal unit  150  (step  908 ). Although the current position of the procedure goes to the step  908  regardless of whether collation succeeds or not, information sent back to the terminal unit  150  varies according to the collation result. Then, the terminal unit  150  performs processing for displaying the result of the contents download request and storing the result (step  909 ).  
         [0084]      FIG. 10  is a flow chart showing a processing procedure in a batch contents download method used in the system having the contents management device  110 , the license management device  120 , the contents synchronization device  140  and the terminal units  150 .  
         [0085]     The contents management processing portion  621  of each terminal unit  150  sends a request to the contents synchronization device  140  to download contents by batch processing (step  1000 ). Incidentally, the contents to be downloaded by batch processing are selected by the user and specified by the contents synchronization device  140  before the batch download processing. The term “synchronization” means the user&#39;s action made to the contents synchronization device  140 , in which action the user selects contents to be downloaded to the terminal unit  150  so that the latest contents (e.g., news contents or latest reports) can be downloaded when batch download is required.  
         [0086]     Then, the contents synchronization device  140  sends an acquisition request to the contents storage device  130  to acquire contents not cached in the contents synchronization device  140  from the contents list selected by the user in advance (step  1001 ). In the step  1001 , the contents are specified on the basis of the contents identification information.  
         [0087]     Then, the contents storage processing portion  421  of the contents storage device  130  retrieves the designated contents stored in the contents storage DB  431  of the contents storage device  130  on the basis of the contents identification information sent in the step  1001  (step  1002 ) and judges whether the contents are stored or not (step  1003 ). When the contents are stored in the contents storage DB  431 , the contents storage device  130  sends a license collation request to the license management device  120  to check whether the contents are licensed or not (step  1004 ). Incidentally, license collation may be performed in the contents storage device  130  if the contents storage device  130  can perform the same processing as the license management device  120 .  
         [0088]     The license management device  120  collates the license in accordance with the license collation request sent from the contents storage device  130  (step  1005 ). A result of license collation is sent back to the contents storage device  130  (step  1006 ).  
         [0089]     The contents storage device  130  makes a judgment on the basis of the information of the license collation result sent back from the license management device  120  as to whether license collation succeeds or not (step  1007 ). When license collation succeeds, the use-restricted contents generation processing portion  423  of the contents storage device  130  generates use-restricted contents (step  1008 ). When license collation fails, information indicating failure in collation and incompletion of contents generation is sent back to the contents synchronization device  140  (step  1009 ). Although the current position of the procedure goes to the step  1009  regardless of whether collation succeeds or not, information sent back to the contents synchronization device  140  varies according to the collation result.  
         [0090]     When the contents requested by the user are generated in the step  1008 , a result indicating completion of generation of the requested contents is generated and sent back to the contents synchronization device  140  (step  1009 ). The contents synchronization device  140  judges whether all the contents requested by the user have been already acquired or not (step  1010 ). When all the contents have been not acquired yet, the current position of the procedure goes back to the contents acquisition request processing (step  1001 ) to acquire remaining contents. On the other hand, when all the requested contents have been already acquired, the contents synchronization device  140  performs contents synchronization processing (step  1011 ). In the step  1011 , batch contents download is performed while the contents synchronization processing portion  523  of the contents synchronization device  140  cooperates with the contents synchronization processing portion  624  of the terminal unit  150  to intend data synchronization.  
         [0091]     Finally, the terminal unit  150  checks whether all the contents requested by the user have been already downloaded (i.e., synchronization processing has been already performed) or not (step  1012 ).  
         [0092]      FIG. 11  is a view showing a user-based license transfer management table which is a data table for managing the number of licenses collected from each user, the number of licenses purchased from each user and the number of incentive points given to each user and which is stored in the user-based license management DB  331  in this embodiment. The user-based license transfer management table  1100  has, as data items, user ID  1101 , number of collected licenses  1102 , number of purchased licenses  1103 , and number of incentive points  1104 .  
         [0093]     The user ID  1101  is a number unique in this system for identifying each user. The number of collected licenses  1102  and the number of purchased licenses  1103  are accounted numbers of licenses collected and purchased by the contents management device  110  from each user. The number of incentive points  1140  is a number of points added when each user returns licenses without paying any fee (i.e., the contents management device  110  collects licenses from each user) or when each user sells licenses (i.e., the contents management device  110  purchases licenses from each user). Further, each user can purchase new contents or upgrade the version of contents by using the incentive points.  
         [0094]      FIG. 12  is a view showing a transaction management table which is provided for managing processing concerning sale, collection and purchase of contents and which is stored in the license management DB  432  of the contents storage device  130 . The transaction management table  1200  has, as data items, transaction ID  1201 , user ID  1202 , contents ID  1203 , license type  1204 , transaction flag  1205 , and date of transaction  1206 .  
         [0095]     The transaction ID  1201  is a number unique in this system for identifying each transaction in the transaction management table. The user ID  1202  is a number for identifying each user. The contents ID  1203  is a number for identifying contents. The user ID  1202  and the contents ID  1203  as well as the transaction ID  1201  are numbers unique in this system. The license type  1204  indicates the license type of contents. For example, the license type  1204  indicates the audiovisual/playback term such as an indefinite term, a half year, etc. The transaction flag  1205  indicates which of license collection, license purchase and use of points was performed as each transaction. When the flag has a value of zero, the flag indicates that the transaction performed was ordinary sale. When the flag has a value of 1, the flag indicates that the transaction performed was collection. When the flag has a value of 2, the flag indicates that the transaction was purchase. When the flag has a value of 3, the flag indicates that the transaction was use of points. The date of transaction  1206  indicates the date when the transaction was performed.  
         [0096]      FIG. 13  is a view showing a merchandise management table indicating licenses of contents and selling prices of the licenses.  
         [0097]     The merchandise management table  1300  is stored in the contents storage DB  431  of the contents storage device  130 . The merchandise management table  1300  has, as data items, contents ID  1301 , license type  1302 , version  1303 , selling price  1304 , purchasing price  1305 , purchase point  1306 , collection point  1307 , and validated date of price  1308 .  
         [0098]     The contents ID  130  is a number for identifying contents to be sold. Each user selects the contents ID and trades contents. The license type  1302  indicates the license type of contents. For example, the license type  1302  indicates a audiovisual/playback term such as an indefinite term, a half year, etc. The version  1303  indicates the version of contents. The selling price  1304  indicates a price used for selling contents. The purchasing price  1305  indicates a price for purchasing contents from each user. In collection of contents from each user, incentive points called collection point  1307  are prepared in consideration of the user&#39;s benefit because contents are received from the user without a fee. The validated date of price  1308  indicates the validated date of the selling price  1304  and the purchasing price  1305 . The validated date of price  1308  may be used as the validated date of the purchase point  1306  and the collection point  1307 .  
         [0099]     As described above, in the digital contents license and incentive point management system according to this embodiment, licenses of digital contents can be recycled because digital contents license sale is performed in such a manner that unnecessary one of licenses of contents available on the market is collected or purchased from each user and incentive such as issuing of new licenses or addition of points is given to the user as an owner of the license on the basis of user information, contents information, or the like, picked up from the license.  
         [0100]     In addition, user&#39;s convenience can be improved because licenses (rights of audiovisual display/playback) of sold digital contents can be collected or purchased from each user and because other digital contents or upgraded version digital contents can be sold at special prices to the user or incentive points can be given to the user. Accordingly, unnecessary digital contents on digital contents distributing business can be recycled.  
         [0101]     Incidentally, digital contents licensed up to the expiration date for use must be originally kept at hand of the user purchasing the digital contents. It may be however hardly said that audiovisual display/playback of digital contents with only one of diversified apparatuses large in number is convenient to the user. To improve user&#39;s convenience, it is necessary that digital contents can be downloaded anywhere at any time for audiovisual display/playback if the apparatus used has been already registered and can be connected to a network. This can be achieved when the license and the body of digital contents are managed by a contents management system (contents management server) on the network. The user having rights of audiovisual display of digital contents can download the digital contents in an expiration date-set state for use of audiovisual display/playback as occasion demands. This is generally called network archive service of digital contents (see the contents archive service site in  FIG. 1 ).  
         [0102]     The point of difference of the network archive service used in the invention from the ordinary archive service is that the expiration date for use of audiovisual display/playback is set in the downloaded digital contents. Because the expiration date for use of audiovisual display/playback is set, audiovisual display/playback can be disabled when a predetermined term has passed after download of the contents to a plurality of apparatuses. This makes it possible to download digital contents to a plurality of apparatuses possessed by each user and collect or purchase the licenses of the digital contents from each user. Because digital contents can be downloaded for audiovisual display/playback at any time when audiovisual display/playback is required, user&#39;s convenience is not worsened.  
         [0103]     The user using the network archive service has the following convenience. Even in the case where an apparatus possessed by the user breaks down, there is no fear that digital contents purchased by the user may vanish because the purchased digital contents are present on the site. Accordingly, the digital contents purchased by the user can be accessed and downloaded by the user at any time safely.  
         [0104]     A personal digital assistant (PDA) may be one of apparatuses possessed by the user. It cannot be said that the data storage capacity of the PDA is large compared with that of a general PC. The way of downloading digital contents necessary for audiovisual display/playback as occasion demands is convenient to the user.  
         [0105]     According to the invention, in digital contents license sale, licenses available on the market can be collected or purchased from each user, so that licenses of digital contents can be recycled.  
         [0106]     It should be further understood by those skilled in the art that although the foregoing description has been made on embodiments of the invention, the invention is not limited thereto and various changes and modifications may be made without departing from the spirit of the invention and the scope of the appended claims.