DGS-3700-12/DGS-3700-12G Series Layer 2 Gigabit Ethernet Switch User Manual
92
IGMP Snooping
Internet Group Management Protocol (IGMP) snooping allows the Switch to r eco gnize IG MP queries and re ports s ent
between network stations or devices and an IGMP host. When enabled for IGMP snooping, the S witch can open or
close a port to a specific device based on IGMP messages passing throug h the Switch.
In order to use IGMP Snooping it must first be enabled for the entire Switch (see the DGS-3700-12/DG S-3700-12G
Switch Series Web Management Tool). You may then fine-tune the settings for each VLAN using the IGMP
Snooping link in the L2 Features folder. When enabled for IGMP snooping, the Switch can ope n or close a port to a
specific multicast group member based on IGMP messages sent from the device to the IGMP host or vice versa. T he
Switch monitors IGMP messages and discontinues forwarding multicast packets when there are no longer hosts
requesting that they continue.

IGMP Snooping Settings

Use the IGMP Snooping Settings window to enable or disable IGMP Snooping on the Switch. To modify the settin gs,
click the Edit button under Parameter Settings and a new table will app ear for the user to configure.
To view this window, click L2 Features > IGMP Snooping > IGMP Snooping Settings as shown below:
Figure 3 - 28 IGMP Snooping Settings window
Clicking the Edit button will open the IGMP Snooping Parameters Settings window, shown below:
Figure 3 - 29 IGMP Snooping Parameters Settings - Edit window
The following fields can be set:
Parameter Description
VLAN ID This is the VLAN ID that, along with the VLAN Name, ident ifies the VLAN for which t he user
wishes to modify the IGMP Snooping Settings.
VLAN Name This is the VL AN Name that, along with the VLAN ID, identifies the V LAN for which the user
wishes to modify the IGMP Snooping Settings.
Rate Limit Displays the rate limitation.
Querier IP The querier IP address to send IGMP queries.
Querier Expiry Displays the querier expiry time.