About this interactive
From the lesson:
- **A VLAN is a network carved out of switch ports.** Ports in one VLAN form one network and one broadcast domain, whichever switch or building they are in.
- **Trunks carry VLANs between switches,** so VLAN 30 in building A and VLAN 30 in building D are still one network.
- **Different VLANs are different networks,** even on the same switch. Traffic between them goes through a router, which is where you control what may cross.
- **The default VLAN on a Cisco switch is VLAN 1.** Out of the box every port is in it. (The video once says "VLAN 1 is our default gateway"; it means the default VLAN.)
What you'll learn
- Decide whether two hosts share one VLAN, and so one network and broadcast domain, or sit in different VLANs that need a router between them
- Read a VLAN by the port it is assigned to, not by which switch or building a host is in, including VLAN 1 on an unconfigured switch
Aligned to
Cisco CCNA
2.1
Configure and verify VLANs (normal range) spanning multiple switches
Key terms
- Virtual LAN
VLAN
- A logical grouping of network devices that behave as if they are on the same network regardless of physical location.
- Broadcast Domain
- A network segment in which a broadcast sent by one device is received by all other devices within that segment; routers define the boundaries of broadcast domains by not forwarding broadcast traffic.
- Default VLAN
- The pre-configured VLAN on a switch that all ports belong to out of the box, allowing immediate operation before any custom VLAN programming; on Cisco switches this is VLAN 1, which cannot be deleted or renamed.
- Access Port
- A switch port that belongs to a single data VLAN and sends and receives untagged frames, used for connecting end devices such as PCs and printers. An access port may additionally carry a tagged voice VLAN for an IP phone without becoming a trunk.
- VLAN Trunk
- A point-to-point link between two switches that carries traffic for multiple VLANs simultaneously using IEEE 802.1Q tagging.
- Inter-VLAN Routing
- The process of forwarding traffic between two or more VLANs using a Layer 3 device, which is required because VLANs are separate broadcast domains and cannot communicate at Layer 2 alone. Inter-VLAN routing can be implemented using a physical router with a trunk link (router-on-a-stick), a multilayer switch with SVIs, or routed ports.
Topics
Vlans
Segmentation
Broadcast Domain
Inter Vlan Routing
Interactive
Streak Sort
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