LevelOne GSW-1676 - Page 120

C ONFIGURING THE S WITCH
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Depending on your network connections, IGMP snooping may not
always be able to locate the IGMP querier. Therefore, if the IGMP
querier is a known multicast router/ switch connected over the network
to a port on this switch, you can manually configure the port (and a
specified VLAN) to join all the current multicast groups supported by
the attached router. This can ensure that multicast traffic is passed to all
the appropriate interfaces within the switch.
• Unregistered IPMC Flooding Enabled - Set the forwarding mode for
unregistered (not-joined) IP multicast traffic. The traffic will be flooded
to the attached VLAN when enabled, or forwarded only to multicast
router ports when disabled. (Default: Enabled)
IGMP Snooping VLAN Configuration
• VLAN ID - The VLAN ID.
• IGMP Snooping Enabled - When enabled both globally (as described
in the preceding section) and on a selected VLAN, the switch will
monitor network traffic on that interface to determine which hosts want
to receive multicast traffic. (Default: Enabled)
• IGMP Querying Enabled - When enabled, the port can serve as the
Querier, which is responsible for asking hosts if they want to receive
multicast traffic. (Default: Disabled)
A router, or multicast-enabled switch, can periodically ask their hosts if
they want to receive multicast traffic. If there is more than one router/
switch on the LAN performing IP multicasting, one of these devices is
elected “querier” and assumes the role of querying the LAN for group
members. It then propagates the service requests on to any upstream
multicast switch/router to ensure that it will continue to receive the
multicast service.