Dell PowerConnect 5548 User Guide - Page 18

Static MAC Entries MAC entries can be manually entered in the Bridging Table, as an alternative to learning them from incoming frames. These user-defined entries are not subject to aging, and are preserved across resets and reboots. For more information, see "Static Addresses" on page 418. Self-Learning MAC Addresses The device enables controlled MAC address learning from incoming packets. The MAC addresses are stored in the Bridging Table. For more information, see "Dynamic Addresses" on page 421. Automatic Aging for MAC Addresses MAC addresses from which no traffic is received for a given period, are aged out. This prevents the Bridging Table from overflowing. For more information, see "Dynamic Addresses" on page 421. VLAN-Aware MAC-Based Switching The device always performs VLAN-aware bridging. Classic bridging (IEEE802.1D), in which frames are forwarded based only on their destination MAC address, is not performed. However, a similar functionality can be configured for untagged frames. Frames addressed to a destination MAC address that is not associated with any port are flooded to all ports of the relevant VLAN. MAC Multicast Support Multicast service is a limited Broadcast service that enables one-to-many and many-to-many connections for information distribution. In Layer 2 Multicast service, a single frame is addressed to a specific Multicast address, from which copies of the frame are transmitted to the relevant ports. When Multicast groups are statically enabled, you can set the destination port of registered groups, as well as define the behavior of unregistered Multicast frames. For more information, see "Multicast" on page 508. 18 Dell PowerConnect 55xx Systems User Guide