A digital rights management system for digital broadcasting based on home servers

This paper presents a digital rights management (DRM) system for digital broadcasting based on home servers (DBHS) using receivers with large-capacity storage devices. DBHS will enable viewers to enjoy ´television anytime/anywhere´ by utilizing these storage functions. Our proposed DRM system is suitable for broadcasting, and allows both rights protection and advanced access to content held on home storage devices (in terms of validity, usage and charge conditions, and so on). We developed a prototype DRM system using a Pentium3 personal computer (1 GHz) in order to evaluate the nonlinear playback and ´trick-play´ modes of encrypted content on the hard disk drive (HDD). Using this prototype, we confirmed that the nonlinear playback of content encrypted using the proposed DRM system could be processed in real time. The functionality in terms of trick-play modes was equal to that of commercially available hard disk recorders. In addition, we developed a security module for the DRM system in the form of a smart card with a built-in processor. We confirmed that the proposed DRM system utilizing the new smart card could be applied to DBHS.