DiffServ体系的组播实现机制

摘要

广域网中IntServ体系需要DiffServ体系的支持来完成组播的应用。然而，即使利用隧道机制，骨干网中一点对多点的组播应用难以较好地得到DiffServ体系的支持。首先分析IntServ体系的组播机制，并讨论DiffServ协议体系中组播机制的实现问题，然后指出DiffServ体系不能较好地支持组播机制的根源在于边界路由器和域内核心路由器，而与域间骨干路由器无关。最后给出解决DiffServ体系实现组播机制的改进方法。%IntServ system in wide area network ( WAN ) needs the support from DiffServ system to achieve its multicast application . However , even with the tunnel mechanism , one-point-to-multipoint multicast applications in backbone networks can still not obtain good support from DiffServ system .In this paper , first we analyse the multicast mechanism in IntServ , and discuss the implementation problem of multicast mechanism in DiffServ protocol system .Then we point out that the problem the DiffServ system cannot well support the multicast mechanism roots in the border routers and the core routers in domain but nothing to do with the core routers of backbone networks inter -domain.An improved method is advanced at last for realising the multicast mechanism in DiffServ .