To perform VLAN hopping, which action should the tester take?

• A. Configure the attacker's machine interface to become a trunk port
• B. Configure the switch to disable VLANs
• C. Use a router to connect VLANs
• D. Enable port security on edge ports only

Answer: (A)

VLAN hopping relies on crossing the boundary between VLANs by carrying traffic from multiple VLANs on a single link. The tester needs to make the attacker's NIC act as a trunk, so that the switch accepts and forwards 802.1Q tagged frames for different VLANs. By configuring the attacker's interface to be a trunk port, traffic from multiple VLANs can be seen on that single link, enabling movement across VLANs if safeguards aren’t in place.

Disabling VLANs on the switch would remove segmentation rather than enable hopping. Using a router to connect VLANs is normal inter-VLAN routing at Layer 3, not a VLAN hopping technique. Enabling port security on edge ports helps restrict or detect unauthorized devices and does not facilitate crossing VLAN boundaries.