Dell PowerConnect 6248 User's Guide - Page 391

Managing Multicast Support The Layer 2 Multicast Forwarding Database is used by the switch to make forwarding decisions for packets that arrive with a multicast destination MAC address. By limiting multicasts to only certain ports in the switch, traffic is prevented from going to parts of the network where that traffic is unnecessary. When a packet enters the switch, the destination MAC address is combined with the VLAN ID and a search is performed in the Layer 2 Forwarding database. If no match is found, then the packet is either flooded to all ports in the VLAN or discarded, depending on the switch configuration. If a match is found, then the packet is forwarded only to the ports that are members of that multicast group. To display the Multicast Support menu page, click Switching →Multicast Support in the tree view. This Multicast Support page contains links to the following features: • Multicast Global Parameters • Bridge Multicast Group • Bridge Multicast Forward • IGMP Snooping • MRouter Status • MLD Snooping Multicast Global Parameters Use the Multicast Global Parameters page to enable bridge multicast filtering or IGMP Snooping on the switch. Parameters for these features can be modified from the Bridge Multicast Forward and IGMP Snooping web pages. To display the Multicast Global Parameters page, click Switching →Multicast Support →Global Parameters in the tree view. Figure 7-73. Multicast Global Parameters Configuring Switching Information 391