Ipv4 Multicast Status - ZyXEL Communications GS1920v2 Series User Manual

How MVR Works
The following figure shows a multicast television example where a subscriber device (such as a
computer) in VLAN 1 receives multicast traffic from the streaming media server, S, through the Switch.
Multiple subscriber devices can connect through a port configured as the receiver on the Switch.
When the subscriber selects a television channel, computer A sends an IGMP report to the Switch to join
the appropriate multicast group. If the IGMP report matches one of the configured MVR multicast group
addresses on the Switch, an entry is created in the forwarding table on the Switch. This maps the
subscriber VLAN to the list of forwarding destinations for the specified multicast traffic.
When the subscriber changes the channel or turns off the computer, an IGMP leave message is sent to
the Switch to leave the multicast group. The Switch sends a query to VLAN 1 on the receiver port (in this
case, an uplink port on the Switch). If there is another subscriber device connected to this port in the
same subscriber VLAN, the receiving port will still be on the list of forwarding destination for the multicast
traffic. Otherwise, the Switch removes the receiver port from the forwarding table.
Figure 151 MVR Multicast Television Example

39.2 IPv4 Multicast Status

Click SWITCHING > Multicast > IPv4 Multicast > IPv4 Multicast Status to display the screen as shown. This
screen shows the IPv4 multicast group information. See
on multicasting.
Figure 152 SWITCHING > Multicast > IPv4 Multicast > IPv4 Multicast Status
The following table describes the labels in this screen.
Table 104 SWITCHING > Multicast > IPv4 Multicast > IPv4 Multicast Status
LABEL
Index
VID
Port
Multicast Group
Chapter 39 Multicast
DESCRIPTION
This is the index number of the entry.
This field displays the multicast VLAN ID.
This field displays the port number that belongs to the multicast group.
This field displays IP multicast group addresses.
GS1920v2 Series User's Guide
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Section 39.1 on page 219 for more information