When configuring a switch to avoid VLAN hopping, which practice should be avoided?

When configuring a switch to avoid VLAN hopping, which practice should be avoided?

• A. Setting the native VLAN to a different VLAN
• B. Using dedicated trunk links
• C. Enabling trunking on all ports
• D. Implementing port security

Answer: (C)

When configuring a switch to avoid VLAN hopping, it is essential to avoid enabling trunking on all ports. Trunking is the method of carrying multiple VLANs over a single link and is typically used between switches or network devices that require access to more than one VLAN. When trunking is enabled on all switch ports, it can expose the network to potential VLAN hopping attacks. VLAN hopping occurs when an unauthorized user sends frames to a switch port configured for a trunk link, potentially gaining access to multiple VLANs unintentionally. By limiting trunking only to the ports that specifically require it (such as those connecting switches), the risk of VLAN hopping can be significantly decreased. This practice ensures that only legitimate devices can traverse across VLANs, maintaining better security control within the network infrastructure. In contrast, other practices mentioned contribute positively to VLAN security – setting the native VLAN appropriately, using dedicated trunk links, and implementing port security can all help to reinforce the overall security posture of the VLANs.

When configuring a switch to avoid VLAN hopping, it is essential to avoid enabling trunking on all ports. Trunking is the method of carrying multiple VLANs over a single link and is typically used between switches or network devices that require access to more than one VLAN. When trunking is enabled on all switch ports, it can expose the network to potential VLAN hopping attacks. VLAN hopping occurs when an unauthorized user sends frames to a switch port configured for a trunk link, potentially gaining access to multiple VLANs unintentionally.

By limiting trunking only to the ports that specifically require it (such as those connecting switches), the risk of VLAN hopping can be significantly decreased. This practice ensures that only legitimate devices can traverse across VLANs, maintaining better security control within the network infrastructure. In contrast, other practices mentioned contribute positively to VLAN security – setting the native VLAN appropriately, using dedicated trunk links, and implementing port security can all help to reinforce the overall security posture of the VLANs.