Igmp Multicast Filtering; Configuring Igmp - Alcatel OMNISTACK 6148 User Manual

IGMP Multicast Filtering

Multicasting is used to support real-time applications such as video conferencing or
streaming audio. A multicast server does not have to establish a separate
connection with each client. It merely broadcasts its service to the network, and any
hosts that want to receive the multicast register with their local multicast switch/
router. Although this approach reduces the network overhead required by a
multicast server, the broadcast traffic must be carefully pruned at every multicast
switch/router it passes through to ensure that traffic is only passed on the hosts that
subscribed to this service.
This switch uses IGMP (Internet Group Management Protocol) to query for any
attached hosts who want to receive a specific multicast service. The switch looks up
the IP Multicast Group used for this service and adds any port that received a similar
request to that group. It then propagates the service request on to any neighboring
multicast switch/router to ensure that it will continue to receive the multicast service.
(For more information, see "IGMP Protocol" on page 4-5.)

Configuring IGMP

This protocol allows a host to inform its local switch/router that it wants to receive
transmissions addressed to a specific multicast group. You can use the IGMP
Configuration screen to configure multicast filtering shown below.
<Apply>
Use <TAB> or arrow keys to move, <Space> to scroll options.
Parameter
IGMP Status
IGMP Query Count*
IGMP Report Delay
* Not supported in the current firmware release.
Note: The default values are indicated in the sample screen.
Alcatel OmniStack 6148
< IGMP Configuration >
IGMP Status
IGMP Query Count
IGMP Report Delay (Seconds) : 10
Description
If enabled, the switch will monitor network traffic to determine which hosts want
to receive multicast traffic. This is also referred to as IGMP Snooping.
The maximum number of queries issued for which there has been no response
before the switch takes action to solicit reports. (Range 2 - 10.)
The time (in seconds) between receiving an IGMP Report for an IP multicast
address on a port before the switch sends an IGMP Query out that port and
removes the entry from its list. (Range 5 - 30.)
: DISABLED
: 2
<Ok>
Configuring the Switch
<Cancel>
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