Owner's Manual

Chapter 27. Multicast Routing and Switching | 755
NETGEAR 8800 User Manual
Figure 92. MVR with STP
In this topology, subscribers are in a Layer 2 cloud on VLAN V1. STP is configured for all
ports of V1. Since V1 spans on the ring as well, multicast cannot be forwarded on V1 blindly.
Forwarding rules (described in
MVR Forwarding on page 751), dictate that multicast traffic is
not forwarded on STP enabled ports. This is to make sure that multiple copies of multicast
packets are not forwarded on the ring. However, since other STP enabled ports on V1
(1:3,1:4) are not part of the ring multicast stream, they need to be configured so that they get
the packets. To configure the ports to receive packets, use the following command
(mentioned previously in
MVR Forwarding ):
configure mvr vlan <vlan-name> add receiver port <port-list>
Note: If the Layer 2 cloud is connected back to ring ports, traffic may end
up leaking into VLAN V1 in the ring. There is no way to avoid that.
So, such topologies must be avoided.
The following is a typical configuration for Switch 1 in Figure 92:
create vlan v1
configure v1 tag 200
configure v1 add port 1:1, 1:2 tag
configure v1 add port 1:3, 1:4
create vlan mvlan
configure mvlan add port 1:1, 1:2
EX_148
Switch1
MSP ring
V1V1
1:3
1:4
MVlan, vc1MVlan, vc1
Switch2Switch4
Vlan V1 cloud