Secure DRM mechanism for offline applications

The paper discusses how digital rights management (DRM) approach can be adapted to work in local or offline mode, without access to global central servers. The focus of this adaptation is not on protection of copyright in a commercial content setting but on restricting access to non-public documents to legitimate users. Therefore we work under assumption that protection against illegal copying is out of scope - any copy of the content is legitimate and can be accessed as long as the user identity and access rights can be properly verified.