3com 3031 Instruccion De Instalación

A multicast network topology may be different from a unicast topology. Some 
routers in the network may only support unicast rather than multicast. Multicast 
static routes are helpful when you need to separate paths between unicast 
datagram and multicast datagram.

For example, when there are routers not supporting multicast on the path 
between the source and the destination, a multicast router can use a tunnel to 
transmit multicast packets to a neighboring multicast router. As shown in 
Figure 157, each unicast router supports unicast only. Multicast datagram 
transmits between multicast routers over a tunnel. If no multicast static route is 
configured, unicast datagram will also be sent over the tunnel. When a multicast 
static route is configured the tunnel is specialized in multicast datagram 
transmission..

Figure 157   Transmitting a multicast datagram over a tunnel

Multicast static routes only have effect on the related multicast routers and will 
not be advertised or imported to any other router in any way .

Multicast Static Route configuration tasks includes:

■

Configure a multicast static route

■

Change the multicast RPF route selection policy