An Efficient and Flexible Authentication Scheme with User Anonymity for Digital Right Management

In recent years, various Digital Right Management (DRM) schemes have been proposed to protect and manage access rights of digital contents. Nevertheless, most DRM schemes do not care for protecting user privacy so the user´s private information is easily compromised. To solve this problem, Zhang et al. proposed a license management scheme with anonymous trust for digital right management. However, we find that their scheme has high computation cost. Besides, their scheme is insecure because the decryption key of the digital content can be easily computed by an attacker. Thus, we propose an efficient and flexible authentication scheme with user anonymity for DRM in this paper. Compared with Zhang et al.´s scheme, the proposed scheme has lower computation cost. In addition, the user privacy can be well-protected without revealing the decryption key. Therefore, the proposed scheme is efficient and practical for the DRM applications.