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[>_] ROOM · Networking
Switching Concepts & VLANs
Master Ethernet switching, MAC address tables, VLAN segmentation, 802.1Q trunking, and inter-VLAN routing with hands-on configuration labs.
Room tasks
1What Is Switching
2MAC Address Tables & Frame Forwarding
3VLANs
4Trunking with 802.1Q
5Inter-VLAN Routing
6Guided Lab: Configuring VLANs and Trunks on a Switch
Frequently Asked Questions
What is a VLAN?
A VLAN is a logical network segment created on a switch. It splits one physical network into separate broadcast domains, which improves performance and limits how far an attacker or misconfiguration can spread.
How does a switch learn MAC addresses?
A switch reads the source MAC address of every incoming frame and records it with the port in its MAC address table. It then forwards later frames only to the correct port, flooding when the address is unknown.
Why is inter-VLAN routing needed?
Devices in different VLANs cannot talk directly, so a router or Layer 3 switch must route between them. This free Codelivly room shows how to set it up and apply access rules between segments.