Extreme Networks ExtremeWare 7.7, Command Reference Manual

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Inter VLAN Layer 2 Multicast
ExtremeWare 7.7 Command Reference Guide 2003
The PMBR also forwards PIM-SM traffic to a PIM-DM network. The PMBR sends a join message to the
RP and the PMBR floods traffic from the RP into the PIM-DM network.
No commands are needed to enable PIM mode interoperation. PIM mode translation is automatically
enabled when a dense mode interface and a sparse mode interface are enabled on the same switch.
Inter VLAN Layer 2 Multicast
Inter VLAN Layer -2 Multicast uses some of the features of Multicast VLAN Registration (MVR) to
forward IP multicast packets to the egress ports.
Multicast VLAN Registration (MVR) is designed to support distributing multicast streams for IPTV to
subscribers over a layer 2 network. In a standard layer 2 network, a multicast stream received on a
VLAN is not forwarded to another VLAN. The streams are confined to the layer 2 broadcast domain. In
an IGMP snooping environment, streams are forwarded only to interested hosts on a VLAN. For
inter-VLAN forwarding (routing) a multicast routing protocol, such as PIM/DVMRP must be deployed.
NOTE
MVR is currently available only on e-series switches.
MVR breaks this basic rule, so that a stream received over layer 2 VLANs is forwarded to another
VLAN, eliminating the need for a layer 3 routing protocol. It simplifies the multicast stream distribution
and is a better solution for IPTV-like services. With MVR, a multicast stream is forwarded to all VLANs
containing interested hosts.