What layer of the OSI model does VLAN tagging occur?

VLAN tagging occurs at Layer 2 of the OSI model, also known as the Data Link layer. This layer is responsible for the node-to-node transfer of data and manages how data packets are placed on the network. VLAN (Virtual Local Area Network) tagging uses protocols such as IEEE 802.1Q to insert a tag in the Ethernet frame, which contains information about the VLAN to which the frame belongs. This tagging is crucial for ensuring that frames are properly directed to the correct VLANs across the network. By encapsulating VLAN information within the data link layer, devices can accurately manage traffic, enforce policies, and optimize network performance within the same physical infrastructure. Thus, understanding VLAN tagging within the context of Layer 2 is essential for effectively managing and configuring network switches in a VLAN environment.