ZyXEL Communications AAM1212-51, User Manual

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AAM1212-51/53 Series User’s Guide
Chapter 19 Multicast VLAN 161
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H A P T E R
19
Multicast VLAN
This chapter describes the Multicast VLAN screens.
19.1 Multicast VLAN Overview
Multicast VLAN allows one single multicast VLAN to be shared among different subscriber
VLANs on the network. This improves bandwidth utilization by reducing multicast traffic in
the subscriber VLANs and simplifies multicast group management.
When the AAM1212 forwards traffic to a subscriber port, it tries to forward traffic to a normal
PVC with the same VLAN ID. If this PVC does not exist, the AAM1212 uses the super
channel instead. This applies to all downstream traffic, not just multicast traffic.
It is suggested to use a super channel for multicast VLAN. If a normal PVC is used and the
multicast VLAN ID is not the same as the PVC’s VID, the AAM1212 does not forward traffic
to this PVC even if the subscriber’s port has joined the multicast VLAN.
Since the AAM1212 might change the subscriber’s VLAN ID to the multicast VLAN ID, both
the subscriber’s port and the Ethernet port should join the multicast VLAN.
19.2 MVLAN Status Screen
Use this screen to look at a summary of all multicast VLAN on the AAM1212. To open this
screen, click
Advanced Application , Multicast VLAN .
Figure 79 MVLAN Status