We present a solution to the problem of privacy invasion in a multiparty digital rights management scheme. (Roaming) users buy content licenses from a content provider and execute it at any nearby content distributor. Our approach, which does not need any trusted third party--in contrast to most related work on privacy-preserving DRM--is based on a re-encryption scheme that runs on any mobile Android device. Only a minor security-critical part needs to be performed on the device's smartcard which could, for instance, be a SIM card.
@article{arxiv.1304.8109,
title = {Unlinkable content playbacks in a multiparty DRM system},
author = {Ronald Petrlic and Stephan Sekula},
journal= {arXiv preprint arXiv:1304.8109},
year = {2013}
}