A secure and mutual-profitable DRM interoperability scheme

In most cases, the use of digital contents on several devices is blocked by digital rights management (DRM) technology to protect the rights of digital content owners, which is called as the DRM's walled garden strategy. This strategy has raised many legal, economical, and ethical problems. DRM interoperability can complement this strategy. However, there is no agreeable systematic interoperability scheme between various DRM systems. This problem cannot be solved without the cooperation and participation of both DRM technology providers and content providers. Some previous attempts to solve the DRM interoperability problem have suggested that both providers need to open parts of their security properties, without the assurance of a beneficial outcome. They were therefore reticent about participating. In this paper, we propose a secure mutual-profitable DRM interoperability scheme which minimizes disclosure of the security properties of DRM technology providers and content providers while preserving their profits. We use a designated proxy re-encryption scheme to allow the providers to designate a proxy which re-encrypts their digital contents and a neutral format scheme to enable format-independent translations. Moreover, we allow the providers to manage and trace their digital contents, and to request additional fees for interoperability services. We describe detailed protocols and analyze the scheme. We also introduce a prototype implementation.