Ethernet and Switching

Ethernet Frames and MAC Addresses

Learn how Ethernet switches use MAC addresses, VLAN context, and forwarding decisions to move Layer 2 frames efficiently.

Intermediate12 min read
Ethernet and Switching lessonNetworkingPractice

UNTIMED COACHING

Practice before the pressure

Use feedback to correct the model, not merely memorize an option position.

GUIDED PRACTICE

Practice the lesson questions

Answer normal lesson questions without a timer. Every answer includes an explanation, and incorrect answers can be tried again before continuing.

CONCEPT MODELS

See the lesson as a system

Use these visual guides to connect the key ideas before answering the questions.

How Ethernet Switches Learn and DecideA switch learns from sources, looks up destinations, and chooses targeted forwarding, flooding, or filtering.
How Ethernet Switches Learn and DecideFrame enters a switch; source information updates a table, then destination information determines the outgoing action.
Incoming Ethernet frameCarries source and destination MACs
Source MACProvides sender address and port
MAC address tableMaps MAC addresses to VLAN ports
Destination lookupChecks destination within the VLAN
MAC Address RolesMAC addressing distinguishes one-interface delivery, group delivery, and administration methods.
MAC Address RolesMAC address categories separate delivery scope from how the address is administered.
MAC addressIdentifies an Ethernet interface
UnicastTargets one network interface
MulticastTargets listening group members
Universally administeredCommon address administration