LIGHTWEIGHT KEY MANAGEMENT OF DRM SYSTEMS

In the past decade, digital rights management's (DRM) goal of helping creators of digital content protect their intellectual property has captured the attention of both academia and industry. The DRM concept has emerged as a blanket term for copyright protection, ownership assertion, digital content authentication, access control and so on. Many corporations, such as Microsoft and Apple, have developed their own DRM systems; however, certain trust relationships are central to their success, especially the content owner's trust in the license server, but such trust is not always justified. Tins paper first addresses the security problem related to collusion attacks in the approach proposed by Jeong at al. Then it presents an efficient and secure key-delivery scheme in a DRM system based on the realistic assumption that the license server may be tempted by extra profit from illegal distribution. The proposed method's main contributions include 1): reducing the threat of collusion attacks by preventing the license server from obtaining a complete content-encryption key; 2): lower computational costs without the need for a public key infrastructure; 3): easy implementation in lightweight mobile devices.