网络层组播存在的可扩展性问题导致路由节点需要记录的组播路由状态数量非常庞大,严重影响了组播技术的推广应用。创建了一种基于共享子树的网络组播状态聚合方法SSMM,首次提出将不同组播树之间互相重叠的子树聚合为单一的共享子树,且完全基于MPLS组播技术设计,大量减少了组播状态数量。SSMM不需要服务器集中计算组播路径,易于实际应用。性能分析和仿真试验证明其优于以往相关工作,较好解决了网络组播的可扩展性问题。 The scalability of multicast at the network layer causes the number of multicast routing states that the routing node needs to record to be very large, which seriously affects the popularization and application of multicast technologies. This paper proposes a SSMM based on shared subtree, which firstly proposes to aggregate subtrees that overlap with each other to form a single shared subtree. Based on the design of MPLS multicast technology, a large number of subtrees are reduced The number of multicast status. SSMM server does not require centralized computing multicast path, easy to practical application. Performance analysis and simulation tests prove that it is better than the previous related work, which solves the problem of scalability of network multicast.