If a node is on a calculated route for a connection it will install forwardingstate for the connection.
如果节点处于所计算的用于连接的路由上，则它将为连接安装转发状态。
2
And a forwarding table for multicast traffic should be built according to the changes of the forwardingstate.
根据转发状态的变化情况，构建出组播数据的二层转发表。
3
In traditional IP multicast, data for a given group is forwarded through a tree structure covering the members of this group. The on-tree routers must maintain a per-group forwardingstate.