Which statement about VLAN tagging on trunk links is true?

Which statement about VLAN tagging on trunk links is true?

• A. Trunk links carry traffic for multiple VLANs using tagging (802.1Q).
• B. Trunk links carry traffic for a single VLAN with no tagging.
• C. Access ports carry tagged frames for multiple VLANs.
• D. VLAN tagging is only used on wireless networks.

Answer: (A)

Trunk links are designed to carry traffic for multiple VLANs on a single physical connection by tagging frames with VLAN identifiers using the 802.1Q standard. This tagging lets both ends of the link know which VLAN each frame belongs to, so traffic from different VLANs can share the same wire without mixing. Some designs use an untagged native VLAN, but tagging is the mechanism that multiplexes multiple VLANs over one trunk. Carrying a single VLAN with no tagging would defeat that purpose, since trunks exist to transport multiple VLANs. Access ports, by contrast, connect end devices to one VLAN and typically send untagged frames. VLAN tagging is used on wired networks as well as wireless, so it isn’t limited to Wi‑Fi. In short, trunk links carry traffic for multiple VLANs using tagging (802.1Q).

Trunk links are designed to carry traffic for multiple VLANs on a single physical connection by tagging frames with VLAN identifiers using the 802.1Q standard. This tagging lets both ends of the link know which VLAN each frame belongs to, so traffic from different VLANs can share the same wire without mixing. Some designs use an untagged native VLAN, but tagging is the mechanism that multiplexes multiple VLANs over one trunk.

Carrying a single VLAN with no tagging would defeat that purpose, since trunks exist to transport multiple VLANs. Access ports, by contrast, connect end devices to one VLAN and typically send untagged frames. VLAN tagging is used on wired networks as well as wireless, so it isn’t limited to Wi‑Fi.

In short, trunk links carry traffic for multiple VLANs using tagging (802.1Q).