Information terminal device and content backup method

Abstract

A management information generating section generates management information in which the correspondence between content data and rights data is described when a Digital Content Format container containing encrypted content data and a rights object described in association with a right to decrypt the content data are stored in an external media card. A backup section writes the Digital Content Format container, rights object and management information into the external media card.

1 . A removable storage medium which stores encrypted content data and rights data used for decrypting the encrypted content data, wherein the encrypted content data and the rights data are managed by an information terminal, said removable storage medium comprising: 
 a first area which stores an item of encrypted content data based on a request from the information terminal;    a second area which stores an item of rights data based on a request from the information terminal; and    a third area which stores one of first management data and second management data based on a request from the information terminal, wherein the first management data is generated by the information terminal when it is detected that the same encrypted content as an item of encrypted content data to be stored is not stored on the removable storage medium, and the first management data includes first identification information identifying the item of encrypted content data to be stored and second identification information identifying a corresponding item of rights data, and wherein the second management data is generated by the information terminal when it is detected that the same encrypted content as the item of encrypted content data to be stored is stored on the removable storage medium, and the second management data includes third identification information identifying the item of encrypted content data already stored on the removable storage medium and the second identification information identifying the item of rights data.    
   
   
       2 . The removable storage medium according to  claim 1 , wherein both the first management data and the second management data include fourth identification information identifying the information terminal.  
   
   
       3 . The removable storage medium according to  claim 1 , wherein the second management data includes relational information that identifies a previously stored one of the first management data and the second management data.  
   
   
       4 . A removable storage medium which stores encrypted content data and rights data used for decrypting the encrypted content data, wherein the encrypted content data and the rights data are managed by an information terminal, said removable storage medium comprising: 
 a first area which stores an item of encrypted content data transmitted from the information terminal;    a second area which stores an item of rights data transmitted from the information terminal; and    a third area which stores one of first management data and second management data transmitted from the information terminal, wherein the first management data is generated by the information terminal when it is detected that the same encrypted content as an item of encrypted content data to be stored is not stored on the removable storage medium, and the first management data includes first identification information identifying the item of encrypted content data to be stored and second identification information identifying a corresponding item of rights data, and wherein the second management data is generated by the information terminal when it is detected that the same encrypted content as the item of encrypted content data to be stored is stored on the removable storage medium, and the second management data includes third identification information identifying the item of encrypted content data already stored on the removable storage medium and the second identification information identifying the item of rights data.    
   
   
       5 . The removable storage medium according to  claim 4 , wherein both the first management data and the second management data include fourth identification information identifying the information terminal.  
   
   
       6 . The removable storage medium according to  claim 4 , wherein the second management data includes relational information that identifies a previously stored one of the first management data and the second management data.  
   
   
       7 . A removable storage medium which stores encrypted content data and rights data used for decrypting the encrypted content data, wherein the encrypted content data and the rights data are managed by an information terminal, said removable storage medium comprising: 
 means for storing an item of encrypted content data based on a request from the information terminal;    means for storing an item of rights data based on a request from the information terminal; and    means for storing one of first management data and second management data based on a request from the information terminal, wherein the first management data is generated by the information terminal when it is detected that the same encrypted content as an item of encrypted content data to be stored is not stored on the removable storage medium, and the first management data includes first identification information identifying the item of encrypted content data to be stored and second identification information identifying a corresponding item of rights data, and wherein the second management data is generated by the information terminal when it is detected that the same encrypted content as the item of encrypted content data to be stored is stored on the removable storage medium, and the second management data includes third identification information identifying the item of encrypted content data already stored on the removable storage medium and the second identification information identifying the item of rights data.    
   
   
       8 . The removable storage medium according to  claim 7 , wherein both the first management data and the second management data include fourth identification information identifying the information terminal.  
   
   
       9 . The removable storage medium according to  claim 7 , wherein the second management data includes relational information that identifies a previously stored one of the first management data and the second management data.  
   
   
       10 . A removable storage medium which stores encrypted content data and rights data used for decrypting the encrypted content data, wherein the encrypted content data and the rights data are managed by an information terminal, said removable storage medium comprising: 
 means for storing an item of encrypted content data transmitted from the information terminal;    means for storing an item of rights data transmitted from the information terminal; and    means for storing one of first management data and second management data transmitted from the information terminal, wherein the first management data is generated by the information terminal when it is detected that the same encrypted content as an item of encrypted content data to be stored is not stored on the removable storage medium, and the first management data includes first identification information identifying the item of encrypted content data to be stored and second identification information identifying a corresponding item of rights data, and wherein the second management data is generated by the information terminal when it is detected that the same encrypted content as the item of encrypted content data to be stored is stored on the removable storage medium, and the second management data includes third identification information identifying the item of encrypted content data already stored on the removable storage medium and the second identification information identifying the item of rights data.    
   
   
       11 . The removable storage medium according to  claim 10 , wherein both the first management data and the second management data include fourth identification information identifying the information terminal.  
   
   
       12 . The removable storage medium according to  claim 10 , wherein the second management data includes relational information that identifies a previously stored one of the first management data and the second management data.  
   
   
       13 . A method of storing, on a removable storage medium, encrypted content data and rights data used for decrypting the encrypted content data, wherein the encrypted content data and the rights data are managed by an information terminal, said method comprising: 
 storing, on the removable storage medium, one of first management data and second management data based on a request from the information terminal, wherein the first management data is generated by the information terminal when it is detected that the same encrypted content as an item of encrypted content to be stored is not stored on the removable storage medium, and the first management data includes first identification information identifying the item of encrypted content data to be stored and second identification information identifying a corresponding item of rights data, and wherein the second management data is generated by the information terminal when it is detected that the same encrypted content as the item of encrypted content data to be stored is stored on the removable storage medium, and the second management data includes third identification information identifying the item of encrypted content data already stored on the removable storage medium and the second identification information identifying the item of rights data;    storing on the removable storage medium, based on a request from the information terminal, the item of encrypted content data to be stored, when it is detected that the same encrypted content as an item of encrypted content to be stored is not stored on the removable storage medium, and not storing the item of encrypted content data, when it is detected that the same encrypted content as the item of encrypted content data to be stored is stored on the removable storage medium; and    storing on the removable storage medium, based on a request from the information terminal, the item of rights data corresponding to the item of encrypted content data to be stored.    
   
   
       14 . The removable storage medium according to  claim 13 , wherein both the first management data and the second management data include fourth identification information identifying the information terminal.  
   
   
       15 . The removable storage medium according to  claim 13 , wherein the second management data includes relational information that identifies a previously stored one of the first management data and the second management data.  
   
   
       16 . A method of storing, on a removable storage medium, encrypted content data and rights data used for decrypting the encrypted content data, wherein the encrypted content data and the rights data are managed by an information terminal, said method comprising: 
 storing, on the removable storage medium, one of first management data and second management data transmitted from the information terminal, wherein the first management data is generated by the information terminal when it is detected that the same encrypted content as an item of encrypted content to be stored is not stored on the removable storage medium, and the first management data includes first identification information identifying the item of encrypted content data to be stored and second identification information identifying a corresponding item of rights data, and wherein the second management data is generated by the information terminal when it is detected that the same encrypted content as the item of encrypted content data to be stored is stored on the removable storage medium, and the second management data includes third identification information identifying the item of encrypted content data already stored on the removable storage medium and the second identification information identifying the item of rights data;    storing, on the removable storage medium, the item of encrypted content data to be stored, which is transmitted from the information terminal, when it is detected that the same encrypted content as an item of encrypted content to be stored is not stored on the removable storage medium, and not storing the item of encrypted content data, when it is detected that the same encrypted content as the item of encrypted content data to be stored is stored on the removable storage medium; and    storing, on the removable storage medium, the item of rights data which corresponds to the item of encrypted content data to be stored and which is transmitted from the information terminal.    
   
   
       17 . The removable storage medium according to  claim 16 , wherein both the first management data and the second management data include fourth identification information identifying the information terminal.  
   
   
       18 . The removable storage medium according to  claim 16 , wherein the second management data includes relational information that identifies a previously stored one of the first management data and the second management data.