【摘要】 简要叙述了PIM-SM中两种组播转发树特点及其相关研究,给出了一种PIM-SM组播转发树从SPT变迁到ST的设计,这一变迁是PIM-SM组播转发算法的扩展。通过这一扩展使得PIM-SM组播转发可以动态地在ST和SPT组播转发树之间进行切换,从而可以综合利用两种组播转发树的优势,来适应动态变化的网络,使得PIM-SM组播转发算法能够在扩展性和性能之间达到较好的平衡和优化。通过在实验室组播试验平台上的实际测试,证明这种协议扩展的设计能够较好地满足设计的要求。更多还原

【Abstract】 This paper intro du ces a distribution tree transition mechanism for PIM-SM,which allows multicas t data delivery tree switching from SPT to ST.In fact,the mechanism is an exte nsion of the classical PIM-SM.The extension allows PIM to dynamically switch between ST and SPT,which enables PIM to better adapt to the changing of networ k environment.You can use this mechanism to resolve the conflict between scalab ility and performance of multicast routing protocols.Our simulation results re veal that the mechanism performs well as expected.更多还原