MPEG-21 Rights Expression Language: Enabling Interoperable Digital Rights Management

The Internet has spawned a revolution in the way people distribute content and access services. At the same time, the availability of broadband and wireless networks has increased, as have the capability and portability of computing and consumer electronic devices. These factors have fueled the development of new technologies to automate, manage, and secure content flow and service access over the Internet. This paper deals with the recently approved ISO standard, MPEG-21 Rights Expression Language (REL). This language is precise, flexible, extensible, and rich in expressing rights. Thus, it can support reliable, flexible, and cost-effective interoperable digital rights management (DRM) systems and applications for electronic commerce and enterprise management of content and services. It is an international standard for expressing and interpreting rights for using and distributing content, resources, and arid services. As an enabling technology for interoperable DRM, its' adoption by industry and incorporation into products certainly takes time. The challenge is to proliferate the REL's adaptation across many different DRM systems as well as conditional access and authorization systems. Moreover, the REL must pervade not only entertainment but also many other applications, such as enterprise, medical information, and even privacy protection.