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USING MULTICAST FILTERING

 

Multicast filtering improves the performance of networks that carry multicast traffic.

This chapter explains multicasts, multicast filtering, and how multicast filtering can be implemented on your Switch. It covers the following topics:

 

What is an IP Multicast?

 

Multicast Filtering

 

IGMP Multicast Filtering

 

For detailed descriptions of the web interface operations and the

 

command line interface (CLI) commands that you require to manage the

 

Switch please refer to the Management Interface Reference Guide

 

supplied in HTML format on the CD-ROM that accompanies your Switch.

 

 

What is an IP

A multicast is a packet that is intended for “one-to-many” and “many-

Multicast?

to-many” communication. Users explicitly request to participate in the

 

communication by joining an endstation to a specific multicast group. If

 

the network is set up correctly, a multicast can only be sent to an

 

endstation or a subset of endstations in a LAN, or VLAN, that belong to

 

the relevant multicast group.

Multicast group members can be distributed across multiple subnetworks; thus, multicast transmissions can occur within a campus LAN or over a WAN. In addition, networks that support IP multicast send only one copy of the desired information across the network until the delivery path that reaches group members diverges. It is only at these points that multicast packets are replicated and forwarded, which makes efficient use of network bandwidth.

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3Com 3 manual Using Multicast Filtering, Relevant multicast group