Abstract
In today's multimedia world digital content is easily available to and widely used by end consumers. On the one hand high quality, the ability to be copied without loss of quality and the existence of portable players make digital content, in particular digital music, very attractive to consumers. On the other hand the music industry is facing increasing revenue loss due to illegal copying. To cope with this problem so called Digital Rights Management (DRM) systems have been developed in order to control the usage of content. However, currently no vendor and no DRM system is widely accepted by the market. This is due to the incompatibility of different systems, the lack of open standards and other reasons. This paper analyzes the current situation of DRM systems, derives requirements for DRM systems and presents technological building blocks to meet these requirements. Finally, a new idea for a DRM system was presented that respects both users and providers interests at the same time. The basic principle relies on the idea that in order to publish content, a user needs to sign that content with his certified digital signature. The concept is based on a five level approach that can be seen as an upgrade path adding functionality as the level increases. The system is open for future extensions and offers benefits both for users and content providers.