Abstract: With the properties of a new document format CEBX, a segment-based dynamic digital rights management scheme (SDDRM) is proposed to provide document encryption with hierarchical key management and fine-grained rights management which includes authorization adding, authorization update, and authorization aggregation. SDDRM includes a document encryption and packaging protocol, a document request and download protocol and a license request and download protocol. SDDRM can implement “authorization on-demand” and support the reading experience of what you see is what you buy. Further study shows that SDDRM is flexible, secure and provides personalized access control. The proposed scheme maintains the fine-grained protection of an e-document and meets the needs of new business model in digital publishing industry.

Key words: DRM, fine-grained authorization, authorization management, hierarchical key management

摘要： 结合新一代文档格式CEBX，提出一种电子文档动态版权管理方案SDDRM。基于等级密钥管理方法，以段为单位，对电子文档进行加密、授权以及授权的追加、更新与合并。SDDRM包括文档加密封装、文档请求与下载、License请求与下载使用等协议，能够根据客户需求提供按需授权的功能，实现所见即所买的阅读体验。通过对SDDRM的进一步分析，表明SDDRM能提供用户个性化的访问控制，兼顾授权的灵活性和安全性。SDDRM能够实现对数字内容的精细化保护，满足数字出版新型业务发展的需要。

关键词: 数字版权保护, 细粒度授权, 授权管理, 等级密钥