• MAC address learning: Switches must learn
about the network to make intelligent decisions.
Because of the size and changing nature of networks,
switches have learned how to discover
network addresses and keep track of network
changes. Switches do this by finding the address
information contained in the frames flowing
through the network, and they maintain private
tables with that information.
• Forwarding and filtering: Switches must decide
what to do with traffic. These decisions are
based on the switch’s knowledge of the network.
• Segmenting end stations: Switches must also have
mechanisms for segregating users into logical
groupings (virtual LANs [VLAN] or broadcast
domains) to allow efficient provisioning of service.