Abstract: A method for playing multimedia content encrypted based on digital rights management (DRM) by a terminal apparatus having a web server module unit, the method comprising: receiving a request for playing the multimedia content encrypted based on DRM; converting a local file path via which the multimedia content encrypted based on DRM corresponding to the received play request is stored into a web server URL path for the web server module unit; providing the web server URL path to a multimedia device player for playing the multimedia content encrypted based on DRM; when the multimedia device player accesses the web server module unit by using the web server URL path, checking whether there is a session being connected to the web server URL; and controlling whether to decode the multimedia content encrypted based on DRM depending on the checking results.

Abstract: A DRM service providing method of a DRM cloud server is provided. The DRM service providing method includes receiving a request for a DRM management service from a contents service company; sending a DRM cloud agent for the contents service company to a server of the contents service company; if a contents provider terminal device sends a request for registration of specific contents by using the DRM cloud agent allotted to the contents service company, packaging the contents corresponding to the received request for registration of the specific contents to DRM contents; and storing the packaged DRM contents, an encryption key for the packaged DRM contents and information upon permissions for use of the packaged DRM contents.

Abstract: A DRM contents using method of a terminal apparatus is provided. The method includes generating a refund list file including contents identification information upon DRM contents for which a user of the terminal apparatus has received a refund; if a use of first DRM contents is requested from the terminal apparatus, comparing first contents identification information corresponding to the first DRM contents with the contents identification information in the refund list file; and determining usability of the first DRM contents based on the comparison result.

Abstract: The present invention relates to a method and system of synchronizing data between a contents providing system and a portable device via network. More particularly, the present invention relates to a method and system of transmitting predetermined data of contents, which requires digital rights protection, to a portable device, wherein a contents providing system and a synchronization information system are connected with a synchronization client installed in a computer to which the portable device is connected.