Multicast Filtering 3

Web – Click Priority, ACL CoS Priority. Select a port, select an ACL rule, specify a CoS priority, then click Add.

Figure 3-94 ACL CoS Priority

CLI – This example assigns a CoS value of zero to packets matching rules within the specified ACL on port 1.

Console(config)#interface ethernet

1/1

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Console(config-if)#map access-list

ip bill cos 0

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Console(config-if)#

 

 

 

 

 

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.

Unicast Flow

Multicast Flow

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

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