IP Multicast Routing Protocol
The functions supporting IP multicasting are added under the
IP Multicast Routing Protocol
folder, from the
Layer 3 IP Networking
folder.
IGMP Snooping
,
DVMRP
, and
PIM-DM
can be enabled or disabled on the Switch without changing the individual protocol’s configuration.
IGMP Interface Configuration
The Internet Group Multicasting Protocol (IGMP) can be configured on the Switch on a per-IP interface basis.To view the
IGMP Interface Table
, open the
IP Multicast Routing Protocol
folder under
Configuration
and click
IGMP Interface Settings
. Each IP interface configured on the Switch is
displayed in the below
IGMP Interface Table
dialog box.To configure IGMP for a particular interface, click the corresponding hyperlink for that IP interface.
This will open another
IGMP Interface Configuration
window:
Figure 6- 130. IGMP Interface Table
Figure 6- 131. IGMP Interface Configuration window
This window allows the configuration of IGMP for each IP interface configured on the Switch. IGMP can be configured as Version 1 or 2 by toggling the
Version
field using the pull-down menu.The length of time between queries can be varied by entering a value between 1 and 65,535 seconds in the
Query Interval
field.The maximum length of time between the receipt of a query and the sending of an IGMP response report can be varied by entering a value in the
Max
Response Time
field.
The
Robustness Variable
field allows IGMP to be ‘tuned’ for sub-networks that are expected to lose a lot of packets.A high value (max. 255) for the
robustness variable will help compensate for ‘lossy’ sub-networks.A low value (min. 2) should be used for less ‘lossy’ sub-networks.
The following fields can be set:
Parameter
Description
Interface Name
Displays the name of the IP interface that is to be configured for IGMP.This must be a previously configured IP
interface.
IP Address
Displays the IP address corresponding to the IP interface name above.
Version
Enter the IGMP version (1 or 2) that will be used to interpret IGMP queries on the interface.
Query Interval
Allows the entry of a value between
1
and
65535
seconds, with a default of 125 seconds.This specifies the
length of time between sending IGMP queries.
Max Response Time
Sets the maximum amount of time allowed before sending an IGMP response report.A value between 1 and 25
seconds can be entered, with a default of 10 seconds.
Robustness Variable
A tuning variable to allow for subnetworks that are expected to lose a large number of packets.A value
between 2 and 255 can be entered, with larger values being specified for subnetworks that are expected to lose
larger numbers of packets.
Last Member Query Interval
Specifies the maximum amount of time between group-specific query messages, including those sent in
response to leave group messages.A value between 1 and 25.The default is 1 second.
State
This field can be toggled between Enabled and Disabled and enables or disables IGMP for the IP interface.The
default is Disabled.
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Allied Telesyn AT-9724TS High-Density Layer 3 Stackable Gigabit Ethernet Switch