ZyXEL Communications ES-100, User Manual

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Chapter 17 IGMP
MES-2110 User’s Guide
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MVR only responds to IGMP join and leave control messages from multicast
groups that are configured under MVR. Join and leave reports from other multicast
groups are managed by IGMP snooping.
The following figure shows a network example. The subscriber VLAN (1, 2 and 3)
information is hidden from the streaming media server, S. In addition, the
multicast VLAN information is only visible to the MES-2110 and S.
Figure 57 MVR Network Example
17.4.1 Types of MVR Ports
In MVR, a source port is a port on the MES-2110 that can send and receive
multicast traffic in a multicast VLAN while a receiver port can only receive
multicast traffic. Once configured, the MES-2110 maintains a forwarding table that
matches the multicast stream to the associated multicast group.
17.4.2 MVR Modes
You can set your MES-2110 to operate in either dynamic or compatible mode.
In dynamic mode, the MES-2110 sends IGMP leave and join reports to the other
multicast devices (such as multicast routers or servers) in the multicast VLAN.
This allows the multicast devices to update the multicast forwarding table to
forward or not forward multicast traffic to the receiver ports.
In compatible mode, the MES-2110 does not send any IGMP reports. In this case,
you must manually configure the forwarding settings on the multicast devices in
the multicast VLAN.
17.4.3 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, via the MES-2110. Multiple subscriber devices can
connect through a port configured as the receiver on the MES-2110.
When the subscriber selects a television channel, computer A sends an IGMP
report to the MES-2110 to join the appropriate multicast group. If the IGMP report
matches one of the configured MVR multicast group addresses on the MES-2110,