Decision Making in DRM System Rights Exporting

Digital rights management (DRM) has been widely used in copyright protection. The nature of DRM leads to incompatibility between different DRM systems. Many authors have produced solutions for generating DRM interoperability. However, decisions making in rights exporting, identified as one of the most important aspects in DRM interoperability, still requires intensive research effort. This thesis studies how the characteristics of rights influence decisions making in rights exporting, and how to mitigate their negative impacts. In order to study how rights can be transferred from one DRM system to another, we built a generic rights model to illustrate the basic elements within rights, i.e. permission and condition, and two types of linkage relationship between the basic elements, the valid-checking path and influential path. Furthermore, the direction and mode of rights flow have been analysed. On the basis of our rights model, we propose a process model for rights exporting and methods for rights decomposition and adaptation. These are further verified in a case study of interoperability between two major DRM standards: OMA DRM version 2 and Windows Media DRM version 10. In summation, this study defines a generic rights model, upon which a process and methods for rights exporting between different DRM systems are proposed and verified in a case study. The rights model and the rights exporting methods can be further specialised for specific DRM systems. Together with the case study, this provides a good starting point for further study of the interoperability between DRM systems. support in my thesis work. She was always there to listen and give advice. Secondly, I would like to thank my supervisor at Nokia, Jukka Kainulainen, for his generous support from my office. I would have not been able to publish the thesis inside Nokia without his supportive help. Special thanks go to my wife, Pan Pan, for her generous daily support throughout my thesis work. Most of the thesis was finished at weekends and during my spare time. Without her good understanding and encouragement, the thesis work would have been much more difficult to finish.