System for permitting off-line playback of digital content, and for managing content rights

摘要

A system for permitting offline content playback and for managing the rights to one or more digital content files within a computer network. The system manages these rights by encrypting the content files to prevent unauthorized access to the files. Encryption is accomplished by using one or more keys which are associated with one or more segments of the content file. These keys enable an authorized user to decrypt and playback the content files at a subsequent time. When the keys are received, a license which specifies the rights of the user regarding the content files, is obtained by the end user system, and verified locally to permit the content playback.