Managing licenses of media files on playback devices

Abstract

Embodiments are described herein for managing licenses of media files on playback devices in a media system. In some embodiments, each media file is purchased based on a number of licenses, each license granting permission to store the media file on a single playback device. Each media file may have an associated number of one or more licenses that specifies the maximum number of playback devices on which the media file may be stored at the same time (concurrently). The media system may comprise a home central licensing (HCL) device, a primary storage device, and playback devices coupled via a network. The primary storage device may be used to initially store newly purchased media files. The HCL device may allow or prohibit distribution of the media files on the primary storage device to playback devices by using a license manager data structure storing licensing information for each media file.

1 - 23 . (canceled) 
     
     
         24 . A system comprising:
 a storage device;   a communications adapter;   processing circuitry configured to:
 access a licensing manager data structure stored in the storage device; 
 determine a version of a media file based on a version identifier of the media file; 
 retrieve, from the licensing manager data structure stored in the storage device, a maximum number of playback devices on which the version of the media file is permitted to be stored; 
 determine whether a number of playback devices on which the media file is stored is lower than the maximum number; and 
 in response to determining that the number of playback devices on which the media file is stored is lower than the maximum number, enable storage of the media file on a playback device by transmitting a command to the playback device using the communications adapter. 
   
     
     
         25 . The system of  claim 24 , wherein the version of the media file identifies a maximum number of playback devices on which the version of the media file is permitted to be stored. 
     
     
         26 . The system of  claim 24 , wherein:
 the media file comprises different licensing versions, each licensing version having a different number of associated licenses for the media file;   the media file is embedded with a version identifier that is mapped to a number of associated licenses by using a license mapping data structure; and   the license mapping data structure comprises a plurality of media file version entries, each media file version entry comprising a version identifier and a number of licenses associated with the version identifier.   
     
     
         27 . The system of  claim 24 , wherein the processing circuitry is further configured to:
 determine a fingerprint, checksum, or hash value of the media file, the fingerprint, checksum, or hash value comprising the version identifier of the media file; and   map the version identifier to a number of associated licenses of the media file by using a license mapping data structure, the license mapping data structure comprising a plurality of media file version entries, each media file version entry comprising a version identifier and a number of licenses associated with the version identifier.   
     
     
         28 . The system of  claim 24 , wherein each license for a media file grants legal permission for a user to store the media file on a single playback device. 
     
     
         29 . The system of  claim 24 , wherein the processing circuitry is further configured to:
 register a plurality of playback devices by using a device registration data structure stored in the storage device, wherein each playback device is registered with only a single central licensing device concurrently, the device registration data structure comprising a plurality of central licensing device entries, each central licensing device entry representing a central licensing device and storing a central licensing device identifier that specifically identifies the central licensing device and one or more playback device identifiers that specifically identifies one or more playback devices currently registered with the central licensing device.   
     
     
         30 . The system of  claim 24 , wherein the processing circuitry is further configured to:
 receive, from a user, a removal request for deleting a particular media file from a particular playback device;   transmit a command using the communications adapter to the particulate playback device to delete the particular media file from the particular playback device; and   decrement, in the licensing manager data structure stored in the storage device, the count of playback devices on which the particular media file is currently stored.   
     
     
         31 . A method comprising:
 accessing a licensing manager data structure;   determining a version of a media file based on a version identifier of the media file;   retrieving, from the licensing manager data structure, a maximum number of playback devices on which the version of the media file is permitted to be stored;   determining whether a number of playback devices on which the media file is stored is lower than the maximum number; and   in response to determining that the number of playback devices on which the media file is stored is lower than the maximum number, enabling storage of the media file on a playback device.   
     
     
         32 . The method of  claim 31 , wherein the version of the media file identifies a maximum number of playback devices on which the version of the media file is permitted to be stored. 
     
     
         33 . The method of  claim 31 , wherein:
 the media file comprises different licensing versions, each licensing version having a different number of associated licenses for the media file;
 the media file is embedded with a version identifier that is mapped to a number of associated licenses by using a license mapping data structure; and 
 the license mapping data structure comprises a plurality of media file version entries, each media file version entry comprising a version identifier and a number of licenses associated with the version identifier. 
   
     
     
         34 . The method of  claim 31 , further comprising:
 determining a fingerprint, checksum, or hash value of the media file, the fingerprint, checksum, or hash value comprising the version identifier of the media file; and   mapping the version identifier to a number of associated licenses of the media file by using a license mapping data structure, the license mapping data structure comprising a plurality of media file version entries, each media file version entry comprising a version identifier and a number of licenses associated with the version identifier.   
     
     
         35 . The method of  claim 31 , wherein each license for a media file grants legal permission for a user to store the media file on a single playback device. 
     
     
         36 . The method of  claim 31 , further comprising:
 registering a plurality of playback devices by using a device registration data structure, a playback device being registered with only a single central licensing device concurrently, the device registration data structure comprising a plurality of central licensing device entries, each central licensing device entry representing a central licensing device and storing a central licensing device identifier that specifically identifies the central licensing device and one or more playback device identifiers that specifically identifies one or more playback devices currently registered with the central licensing device.   
     
     
         37 . The method of  claim 31 , further comprising:
 receiving, from a user, a removal request for deleting a particular media file from a particular playback device;   deleting the particular media file from the particular playback device; and   decrementing, in the licensing manager data structure, the count of playback devices on which the particular media file is currently stored.   
     
     
         38 . A non-transitory computer readable medium having instructions stored thereon comprising sets of instructions for:
 accessing a licensing manager data structure;   determining a version of a media file based on a version identifier of the media file;   retrieving, from the licensing manager data structure, a maximum number of playback devices on which the version of the media file is permitted to be stored;   determining whether a number of playback devices on which the media file is stored is lower than the maximum number; and   in response to determining that the number of playback devices on which the media file is stored is lower than the maximum number, enabling storage of the media file on a playback device.   
     
     
         39 . The computer readable medium of  claim 38 , wherein the version of the media file identifies a maximum number of playback devices on which the version of the media file is permitted to be stored. 
     
     
         40 . The computer readable medium of  claim 38 , wherein:
 the media file comprises different licensing versions, each licensing version having a different number of associated licenses for the media file;   the media file is embedded with a version identifier that is mapped to a number of associated licenses by using a license mapping data structure; and   the license mapping data structure comprises a plurality of media file version entries, each media file version entry comprising a version identifier and a number of licenses associated with the version identifier.   
     
     
         41 . The computer readable medium of  claim 38 , further comprising sets of instructions for:
 determining a fingerprint, checksum, or hash value of the media file, the fingerprint, checksum, or hash value comprising the version identifier of the media file; and   mapping the version identifier to a number of associated licenses of the media file by using a license mapping data structure, the license mapping data structure comprising a plurality of media file version entries, each media file version entry comprising a version identifier and a number of licenses associated with the version identifier.   
     
     
         42 . The computer readable medium of  claim 38 , wherein each license for a media file grants legal permission for a user to store the media file on a single playback device. 
     
     
         43 . The computer readable medium of  claim 38 , further comprising sets of instructions for:
 receiving, from a user, a removal request for deleting a particular media file from a particular playback device;   deleting the particular media file from the particular playback device; and   decrementing, in the licensing manager data structure, the count of playback devices on which the particular media file is currently stored.