Cisco Certified Network Associate (CCNA) Practice Exam 2026 – The Comprehensive All-in-One Guide to Exam Success!

VLAN tagging in Ethernet frames is essential for the identification and separation of different Virtual Local Area Networks (VLANs) within the same physical network. By adding a VLAN tag to an Ethernet frame, network devices can discern which VLAN the frame belongs to, ensuring that data traffic is correctly directed and segregated according to the specified network architecture.

This tagging process allows switches to manage traffic more effectively, as they can identify which frames are associated with which VLANs. It supports the implementation of multiple logical networks on a single physical network infrastructure. By allowing traffic from different VLANs to coexist without interference, VLAN tagging enhances network organization and security.

The other options involve concepts that do not directly relate to the function of VLAN tagging. While VLAN tagging does not eliminate the need for IP addresses, reduce frame sizes, or inherently enhance routing efficiency, it plays a critical role in network configuration and management, making the identification of VLANs the correct and relevant aspect of VLAN tagging in this context.