基于LKH树的动态多播群组批密钥更新方案的优化设计

逻辑密钥层次（LKH）方案是目前多播领域中最有效的密钥管理协议。然而，由于其集中式访问控制和密钥分配方式，限制了组规模的进一步扩展。根据文献[1，2]关于MBone的多播组成员行为的研究和监测结果，援引批处理和优化控制的思想，本文对LKH树的方案进行了改进和扩展，设计了一个基于LKH树的优化批密钥更新方案，并给出了它的协协议和算法。分析表明，该方案克服了原有协议的缺点，增加了组规模的可扩展性，因而适用于大型的动态多播环境。

Optimization Design of the Batch Re-Keying Scheme for Dynamic Multicast Groups Based on the LKH Tree

The logical key hierarchy (LKH) scheme is the most efficient protocol for key management in the field of multicast at present. However, the modes of centralized access control and key distribution limit the extension of their group sizes. In this paper, according to the studies of about the behaviors of multicast group members in the MBone, and the ideas of batch processing and optimization control, an optimized batch re-keying scheme and its algorithm are designed. This scheme overcomes the demerits of the existing protocols and improves the scalability of the group size, and therefore applies to large and dynamic multicast groups.