Abstract
Digital Rights Management (DRM) system can be divided into device-based and smart card-based DRM system. For device-based DRM systems, a digital content is only allowed to be played on a particular device according to the license purchased. Therefore, a user who wants to play the same content on different devices needs to buy more licenses. On the contrary, smart card-based DRM system proposed by Conrado et al. allowed to play a digital content anywhere and anytime once he purchases a license for the media. However, there are some drawbacks in their system. In this paper, the improved system is proposed. Our proposed DRM system retains some useful properties as those in their system, e.g., privacy and mobility. Besides, the proposed also provides more strong properties, including secrecy, and practicability. © 2007 IEEE.