D-Link DES-3028 User Manual Download

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DES-3028 DES-3028P DES-3028G DES-3052 DES-3052P Layer 2 Fast Ethernet Managed Switch

the IGMP Snooping Settings.

VLAN Name

This is the VLAN Name that, along with the VLAN ID, identifies the VLAN for which to modify
the IGMP Snooping Settings.

Query Interval

This field is used to set the time (in seconds) between transmitting IGMP queries. Entries
between

and

65535

seconds are allowed. Default =

125

Max Response Time

This determines the maximum amount of time in seconds allowed before sending an IGMP
response report. This field allows an entry between

and

(seconds). Default =

Robustness Value

Adjust this variable according to expected packet loss. If packet loss on the VLAN is
expected to be high, the Robustness Variable

should be increased to accommodate

increased packet loss. This entry field allows an entry of

255

. Default =

Last Member Query
Interval

This field specifies the maximum amount of time between group-specific query messages,
including those sent in response to leave group messages. Default =

Host Timeout

This is the maximum amount of time in seconds allowed for a host to continue membership
in a multicast group without the Switch receiving a host membership report. Default =

260

Router Timeout

This is the maximum amount of time in seconds a route is kept in the forwarding table
without receiving a membership report. Default =

260

Leave Timer

This specifies the maximum amount of time in seconds between the Switch receiving a
leave group message from a host, and the Switch issuing a group membership query. If no
response to the membership query is received before the Leave Timer

expires, the

(multicast) forwarding entry for that host is deleted. The default setting is 2.

Note: The leave timer does not need to be configured as its action has no effect on the
IGMP snooping settings.

Querier State

Choose

Enabled

to enable transmitting IGMP Query packets or

Disabled

to disable. The

default is

Disabled

Querier Router
Behavior

This read-only field describes the behavior of the router for sending query packets.

Querier

will denote that the router is sending out IGMP query packets.

Non-Querier

will denote that

the router is not sending out IGMP query packets. This field will only read

Querier

when the

Querier State and the State fields have been Enabled.

State

Select

Enabled

to implement IGMP Snooping. This field is

Disabled

by default.

Multicast Fast Leave

This parameter allows the user to enable the

Fast Leave

function.

Enabled

, this function will

allow members of a multicast group to leave the group immediately (without the
implementation of the Last Member Query Timer) when an IGMP Leave Report Packet is
received by the Switch. The default is

Disabled

Data Driven Learning
Aged Out

This parameter allows the user to

Enable

Disable

the

Data Driven Learning Aged Out

function on the Switch.

Click

Apply

to implement the new settings. Click the

Show All IGMP Group Entries

link to return to the

Current IGMP

Snooping Group Entrie

s window.

NOTE:

The Fast Leave function is intended for IGMPv2 users wishing to

leave a multicast group and is best implemented on VLANs that have only
one host connected to each port. When one host of a group of hosts uses
the Fast Leave function, it may cause the inadvertent fast leave of other
hosts of the group.

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