Overview
Virtual Local Area Networks (VLANs) allow network administrators to partition a physical switch into multiple logical networks. Devices in different VLANs cannot communicate directly at Layer 2; they require a router or Layer 3 switch to communicate.
Benefits
- Security: Isolates sensitive traffic (e.g., HR vs. Guest Wi-Fi).
- Performance: Reduces the size of broadcast domains.
- Flexibility: Users can be grouped by department or function rather than physical location.
Implementation
Uses VLAN Tagging (typically 802.1Q) to identify which VLAN a frame belongs to as it travels across trunk links.