Asus GigaX2024SX - Manual (Page 161)

Multicast Filtering
Multicasting is used to support real-time applications such as videoconferencing
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 to
the hosts which subscribed to this service.
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
e to receive the multicast service. This
d network’s
ining
nstead of flooding traffic to all
IGMP (Snooping and Query)
Query – If multicast routing is not supported on other
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/router to ensure that it will continu
procedure is called multicast filtering.
The purpose of IP multicast filtering is to optimize a switche
performance, so multicast packets will only be forwarded to those ports conta
multicast group hosts or multicast routers/switches, i
ports in the subnet (VLAN).
Layer 2
IGMP Snooping and
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