DELL PC2748 User Manual

The PowerConnect 2708, 2716, and 2724 switches support a total of 8K MAC addresses, and the 

PowerConnect 2748 supports a total of 16K MAC addresses.

The switch enables MAC address auto-learning from incoming packets. The MAC addresses are 

stored in the Bridging Table.

MAC addresses from which no traffic is received for a given period of time are aged out. This 

prevents the Bridging Table from overflowing.

In Managed or Secure mode, the switch system always performs VLAN-aware bridging. Classic 

bridging (IEEE802.1D) is not performed (where frames are forwarded based only on their 

destination MAC address). However, a similar functionality may be configured for untagged 

frames. Addresses are associated with ports by learning them from the incoming frames source 

address.

In Unmanaged Mode, the switch performs classic bridging. Frames are forwarded based on their 

destination MAC address only, regardless of the VLAN tag.

The port mirroring mechanism monitors and mirrors network traffic by forwarding copies of 

incoming and outgoing packets from a monitored port to a monitoring port. Users can specify 

which target port receives copies of all traffic passing through one or more source ports.

Storm Control enables limiting the amount of Multicast and Broadcast frames accepted and 

forwarded by the switch. When Layer 2 frames are forwarded, Broadcast and Multicast frames are 

flooded to all ports on the relevant VLAN. All nodes connected to these ports accept and attempt 

to process these frames, thus placing load on both the network links and the host operating system.