Owner's Manual

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- Bridge Multicast Filtering Enabled —Enables or disables bridge Multicast filtering. Disabled is
the default value. IGMP Snooping can be enabled only if Bridge Multicast Filtering is
enabled. This does not appear on all devices’ screens.
-
IGMP Snooping Enabled —Enables or disables IGMP Snooping on the device. This does not
appear on all devices’ screens.
Disabled is the default value. Layer 2 switching forwards Multicast packets to all relevant
VLAN ports by default, treating the packet as a Multicast transmission. While this is
functional, in the sense that all relevant ports/nodes receive a copy of the frame, it is
potentially wasteful as ports/nodes may receive irrelevant frames only needed by a subset of
the ports of that VLAN. Multicast forwarding filters enable forwarding of Layer 2 packets to
port subsets, defined in the Multicast filter database.
When you enable IGMP snooping globally, the switching ASIC is programmed to forward all
IGMP packets to the CPU. The CPU analyzes the incoming packets and determines which
ports are to join which Multicast groups, which ports have Multicast routers generating IGMP
queries, and what routing protocols are forwarding packets and Multicast traffic. Ports
requesting to join a specific Multicast group issues an IGMP report specifying that Multicast
group. This results in the creation of the Multicast filtering database.
The following are fields on the editor in the lowest panel. All are mandatory unless otherwise
described.
Multicast Table —A read-only view of all the Multicast Services on the system. Double clicking a
service, or selecting one and clicking
Edit edits the selected Service/VLAN.
VLAN ID —A pick list of all current VLANS. Only mandatory if you enable GVRP.
Multicast IP Address —Text, an IP Address or None.
- Port Assignments —Click the Right/Left Arrows to assign ports (move from Available Ports to
Assigned Ports
) for this multicast. Reset restores the original port assignments (from the
database), while
Remove All removes any port assignments you have made.
The
Configure button at the bottom of this screen sends the selected configuration to the device.
The
Refresh button queries to update information displayed.