Verifiable Threshold Authorization for Scalable and Secure Digital Rights Management

摘要

With fast development of network computing andstorage technologies, it became more and more convenientto share and spread digital resources through kinds ofnetwork services, however without protection andconstraint of copyright, digital content can be illegallycopied, altered and distributed, which could cause revenueloss to commercial digital resource providers, to solve thisproblem, digital rights management(DRM) is adopted tocontrol copyrights of digital resources in a reasonabledegree. Most of current DRM systems were built up incentered authorization mode which can work efficiently innormal case, but once the DRM administrator isunauthentic or the server collapsed, it will not provideauthentication and authorization service again. In thispaper, a verifiable threshold authorization scheme (VETAS)based on ellipse curve cryptosystem (ECC) and Lagrangepolynomial is adopted for scalable and robust digital rightsmanagement, in which authorization was based on t-out of nqualified members, less than t members cannot implementauthorization, and the system can still work well once partof the members are unauthentic. The advantage of theVETAS scheme is that it works in a “mutual authenticationand threshold authorization” mode, thus end-user and theauthorization center can authenticate each other to enhancesecurity of corresponding identity, another advantage of theVETAS scheme is it can provide real-time rightsmanagement with fairly good robustness and reliability in athreshold authorization mode.