Reselling Digital Content

Digital content, protected by specific terms of use, is currently delivered to customers via a few selected content providers. Allowing arbitrary entities,not just trusted content providers, to resell legitimately purchased,protected digital content to another entity, adds additional challenges to a DRM environment. In this paper, we formally model the problem of reselling digital content, and we provide a secure construction based on one-time(proxy) signatures. Our construction allows an arbitrary seller to resell its digital content to any buyer. We ensure that the identity of the buyer is only known to the seller. The buyer can verify that the purchased content is genuine. After the transaction is completed only the legitimate current owner can use the digital content. Any illegal use can be identified by a trusted authority.