Netgear XCM8806 - 8800 SERIES 6-SLOT CHASSIS SWITCH 사용자 설명서
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Chapter 27. Multicast Routing and Switching
NETGEAR 8800 User Manual
Multicast VLAN Registration
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.
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.
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.
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.
Figure 88. Standard VLAN Compared to an MVR VLAN
, the left side shows a standard VLAN carrying a multicast stream. The host H1
receives the multicast stream because it resides on VLAN Vlan1, but host H2 does not
receive the multicast traffic because no IP multicast routing protocol forwards the stream to
VLAN Vlan2. On the right side of the figure, H2 does receive the multicast stream. Because
Vlan1 was configured as an MVR VLAN, the multicast stream is forwarded to the other
VLANs on the switch. containing hosts that have requested the stream. To configure a VLAN
as an MVR VLAN, use the following command:
receive the multicast traffic because no IP multicast routing protocol forwards the stream to
VLAN Vlan2. On the right side of the figure, H2 does receive the multicast stream. Because
Vlan1 was configured as an MVR VLAN, the multicast stream is forwarded to the other
VLANs on the switch. containing hosts that have requested the stream. To configure a VLAN
as an MVR VLAN, use the following command:
configure mvr add vlan <vlan-name>
Typically, IGMP snooping is enabled, so only hosts that have requested a stream can see the
multicast traffic. For example, another host on Vlan2 cannot receive the traffic unless it has
sent an IGMP request to be included in the group.
multicast traffic. For example, another host on Vlan2 cannot receive the traffic unless it has
sent an IGMP request to be included in the group.
Notice that only Vlan1 is MVR enabled. Configure MVR only on the ingress VLAN. To enable
MVR on the switch, use the following command:
MVR on the switch, use the following command:
enable mvr
EX_142
Switch1
H2 subscribed to G
H1 subscribed to G
Vlan1
Vlan1
Vlan1
Vlan2
Vlan2
Stream to Group G
Vlan1
(MVR Enabled)
H2 subscribed to G
H1 subscribed to G
Stream to Group G
Switch1