Achieving media portability through local content translation and end-to-end rights management

The problem addressed in this paper is that of DRM interoperability. The term DRM interoperability, as used here, refers to approaches that provide for the transfer, from one "upstream" DRM system to another "downstream" DRM system, of DRM protected content and an associated license. We introduce the concept of a Rights Issuer Module (RIM) that is functionally situated in the home network between the upstream device (which includes an upstream-DRM agent) and downstream devices (which each include a downstream-DRM agent). The novelty of our approach lies in the way the RIM handles significant aspects of the translation operations, potentially leaving the upstream and downstream DRM agents intact. Security and implementation advantages of the RIM are discussed. The tradeoffs involved with different RIM implementations are examined.