3Com 2226 PLUS - Manual (Page 50)

50 C HAPTER 4: C ONFIGURING THE S WITCH
IGMP Snooping
This switch uses IGMP (Internet Group Management
Protocol) to query for any attached hosts that want to
receive a specific multicast service. It identifies the ports
containing hosts requesting to join the service and sends
data out to those ports only. It then propagates the
service request up to any neighboring multicast
switch/router to ensure that it will continue to receive
the multicast service. This procedure is called multicast
filtering.
The purpose of IP multicast filtering is to optimize a
switched network’s performance, so multicast packets
will only be forwarded to those ports containing
multicast group hosts or multicast routers/switches,
instead of flooding traffic to all ports in the subnet
(VLAN).
Choose Enabled or Disabled from the IGMP Snooping
Mode drop down menu.
Figure 33 IGMP Snooping Setup Screen
IGMP Query
Choose Enabled or Disabled from the IGMP Query
Mode drop down menu.
Figure 34 IGMP Query Setup Screen