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Digital rights management (DRM) technology aims to distribute digital contents to users in a controlled manner that can protect the copyright of contents. Most previous DRM schemes do not consider user relations and content relations, thus it results in inefficiency and produces much overhead. In this paper, an efficient hierarchical rights authorization scheme for offline content protection (HRAS) is proposed in distance education system of university/college. Based on certain hierarchical rights relations of users and course contents in distance education system, a logical key graph is constructed in HRAS and two algorithms are designed respectively to construct the key graph. A comparison with other DRM schemes has shown that HRAS is efficient and has low overhead.