给出一种基于封装和聚集组播的区分服务组播方案：EADSMCast（Encapsulated and Aggregated DiffServ Multicast）.通过对基于封装的DSMCast方案的改进,在组播分组头部封装聚集树上核心路由器的转发信息,保持了区分服务域中核心路由器的无状态性和可扩展性;同时,通过对聚集组播的组-树匹配算法的改进,使多个具有相同或相似转发结构的组播组共享一棵聚集树,减小了边界路由器中组播路由表的规模.仿真实验结果表明,EADSMCast能够支持异构QoS组播,具良好可扩展性

Proposed in this paper is an encapsulation-and-aggregation-based DiffServ multicast scheme named EADSMCast （ Encapsulated and Aggregated DiffServ Multicast） . Derived from the encapsulation-based DSMCast, EADSMCast encapsulates the forwarding information of all core routers of the aggregated tree into each multicast packet head,thus ensuring the statelessness and scalability of core routers in the service domain. Moreover,by improving the group-tree matching algorithm,several multicast groups with similar forwarding structure may share the same aggregated tree,thus reducing the size of multicast routing table maintained by edge routers. Simulated results indicate that EADSMCast is a scalable scheme for supporting heterogeneous QoS multicast.