SMC Networks SMC6709L2 manual Forwarding and Filtering, Configuring Multicast Filtering

FORWARDING AND FILTERING

Forwarding and Filtering

This switch supports the following types of traffic filtering:

•Multicast Filtering – This switch can forward multicast traffic to host devices that request to join a multicast service, and filter multicast traffic for all other ports which do not require multicast services.

•Static MAC Address – Binds a physical address to a specific port and VLAN. Traffic with a source or destination address found in the static address table will only be passed through the specified interface.

•Port Security – Disables address learning for the specified port. Valid addresses must be learned during a initial training period or statically configured.

•MAC Filtering – Filters specified addresses from the switch or from a specific VLAN.

Configuring 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 to hosts that subscribed to this service.

This switch uses Internet Group Management Protocol (IGMP) to query for any attached hosts that want to receive a specific multicast service. It identifies the ports containing hosts requesting to join a 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 continue to receive the multicast service. This procedure is also called multicast filtering.

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