Towards practical privacy-preserving digital rights management for cloud computing

Unlinkable Content Playbacks in a Multiparty DRM System

“…The approach towards privacy-preserving DRM by Joshi et al [10] also requires a TTP for license checking before content execution. It makes use of a number of cryptographic primitives such as proxy re-encryption, ring signatures and an anonymous recipient scheme to provide unlinkability of content executions.…”

“…The CP creates the license for content i. This license includes a license identifier id, a timestamp ts, the content-id i , the license terms, and the CP's certificate cert cp (10). Note that the license terms depend on the license model, i.e., for execute at most n-times-models, the terms include the maximum number of allowed executions n. For other license models, the terms will differ accordingly.…”

“…5.1) (9). The re-encryption key is then forwarded to the CAD (10). The CAD re-encrypts the encrypted content key (ck i ) pk−tmpsc by employing the R algorithm as in Sect.…”

“…Flexibility in choosing a license model The protocols presented here and in [9,10] allow for a license model to be chosen freely, e.g., content execution at most n times, up to a certain point of time, etc. The protocol presented in [6] does not allow such flexibility-once a license is bought for some content, it may be executed by the user as often as desired.…”

A novel identity-based anonymous authentication scheme from multilinear maps

“…On the definition of security for ring signature, Bendery et al (2006) gave a strongest definition of both anonymity and unforgeability depending on the security strength for ring signature. Due to the unique anonymity and flexibility (such as, no managers and no revocation procedure), ring signature plays an important role in cloud computing for solving privacy issue, which have been suggested in some works (Jensen et al, 2010;Xin et al, 2011;Joshi and Petrlic, 2013). In order to demonstrate how to use ring signature for the anonymous authentication in cloud, we consider a privacy-preserving digital right management (PP-DRM) system (Joshi and Petrlic, 2013).…”