Abstract: Methods, apparatus and system, including computer program products, implementing and using techniques for generating a ticket representing a selection of media files to be transferred from a content server to a playback device. A selection of one or more media files to be transferred to a particular playback device is received. Device identifying information for the particular playback device is received. A ticket based on the device identifying information is generated. The ticket is redeemable for the selected media files and the media files are formatted so that they can only be rendered on the particular playback device. Methods, apparatus and system, including computer program products, implementing and using techniques for redeeming a ticket representing a selection of media files to be transferred from a content server to a particular playback device are also described.

Abstract: Methods, apparatus and system, including computer program products, implementing and using techniques for generating a ticket representing a selection of media files to be transferred from a content server to a playback device. A selection of one or more media files to be transferred to a particular playback device is received. Device identifying information for the particular playback device is received. A ticket based on the device identifying information is generated. The ticket is redeemable for the selected media files and the media files are formatted so that they can only be rendered on the particular playback device. Methods, apparatus and system, including computer program products, implementing and using techniques for redeeming a ticket representing a selection of media files to be transferred from a content server to a particular playback device are also described.

Abstract: Methods, apparatus and system, including computer program products, implementing and using techniques for transferring one or more media files from a content server to a media playback device. A request of one or more media files to be transferred to a particular media playback device is received. The one or more media files have associated expiration rules. Information about the particular media playback device is obtained. Based on the information, it is determined whether the particular media playback device has the capability to enforce the expiration rules associated with the one or more media files. If so, the media files are formatted such that they can only be rendered by the particular playback device and transferred to the device with the expiration rules. A method and apparatus for playing media files and a method and apparatus for updating expiration data are also described.

Abstract: Methods, apparatus and system, including computer program products, implementing and using techniques for delivery of media content. A communication channel is established between a particular digital media playback device and a content server on which media content is stored. Device-identifying information relating to the particular digital media playback device is received through the communication channel. A request for media content to be delivered to the digital media playback device is received. It is determined, based on the device-identifying information, whether the requested media content is playable on the digital media playback device. If the requested media content is playable on the digital media playback device, the requested media content and metadata associated with the media content are obtained and formatted, based on the device-identifying information, for playback on the digital media playback device.

Abstract: Methods, apparatus and system, including computer program products, implementing and using techniques for delivering media files to a particular digital media playback device. The system includes a content server and a download manager. The content server receives device-identifying information obtained from a particular digital media playback device and distributes media files in response to the received device-identifying information. The download manager obtains device-identifying information from a particular digital media playback device that is in communication with the download manager, forwards the obtained device-identifying information to the content server over a public communication network, receives media files over the public communication network from the content server, and distributes the received media files to the particular digital media playback device for playback on the particular digital media playback device.

Abstract: Methods, apparatus and system, including computer program products, implementing and using techniques for delivery of media files to a particular digital media playback device. The system comprises a content server and a download manager located in the digital media playback device. The content server receives device-identifying information obtained from the digital media playback device, and distributes media files in response to the received device-identifying information. The download manager forwards device-identifying information to the content server over a public communication network and receives media files over the public communication network from the content server for playback on the particular digital media playback device.