Multicast Filtering; Defining Igmp Snooping; Figure 3-115. Multicast Home Page - Alcatel OS-LS-6224 User Manual

3
Configuring the Switch

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 or
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 to the hosts
which subscribed to this service.
This section contains information for configuring Multicast forwarding and Multicast
TV, and includes the following sections:

• Defining IGMP Snooping

• Specifying Static Interfaces for a Multicast Group
• Displaying Interfaces Attached to a Multicast Router
• Configuring Multicast TV
• Defining Multicast TV Membership

Figure 3-115. Multicast Home Page

Defining 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
or router to ensure that it will continue to receive the multicast service. This
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