CompTIA Network+ Practice Test 2026 - Free Network+ Practice Questions and Exam Prep Guide

Switch spoofing is a technique that attackers use to gain unauthorized access to multiple VLANs (Virtual Local Area Networks) by exploiting the way switches handle VLAN tagging. In this method, the attacker connects a device to a network switch and tricks the switch into thinking that the device is another switch. This can be accomplished by configuring the attacker's device to send out VLAN trunking protocol (VTP) or Dynamic Trunking Protocol (DTP) messages, which are used by switches to establish trunk links.

A trunk link allows traffic from multiple VLANs to pass through the same physical connection, which means if an attacker successfully creates a trunk link with the switch, they can access all the VLANs that the trunk carries, effectively hopping from one VLAN to another. This poses a significant security risk because it can allow attackers to access sensitive data and resources on VLANs that they should not have access to.

Other techniques, while they can be related to network security issues, do not specifically enable VLAN hopping. IP spoofing involves altering the source address in IP packets to masquerade as another device, but it does not inherently allow access to other VLANs. Packet sniffing is the act of capturing network packets to analyze traffic, and port scanning is a