IP组播中的聚合点选择

在协议无关组播-烯松模型中（PIM-SM0，RP（Rendezvous Point)作为共享树的根，数据包都从源点直接发送到RP，再由RP沿共享树发送到各接收点，在一个组播域里，RP的选择十分重要，文章提出了一种能反映网络拓扑的方法，在一个连通图中，从一个点出发到所有点所经过的最短路径是经过其到所有点的DIJKSTRA树，而DIJKSTRA树的权和都是一样的，不同的RP选择仅是决定于各源点到RP的代价之和，即选择网络的大约的“中心”为RP。

RP Choice in IP Multicast

In current widely used protocol independent multicast-sparse mode,RP(Rendezvous Point)is the root of the shared tree,datagram is sent from source to RP and forwarded along the shared tree. So in a multicast region, the choice of RP is very important. We discuss a way that relates the topology of the network.The way a point to all the other points is its Dijkstra tree in a weighted linked graph,but all Dijkstra trees have the same sum of weight, so we choose the most central point. ;;;