Which standard enables tagging Ethernet frames to support VLANs on a single link?

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Multiple Choice

Which standard enables tagging Ethernet frames to support VLANs on a single link?

VLAN tagging on Ethernet frames is defined by 802.1Q. It inserts a 4-byte tag into the frame (placed after the source MAC address) that carries the VLAN ID, enabling multiple VLANs to share a single physical link—this is known as a trunk. Switches use the tag to keep traffic separated by VLAN and forward it only to the matching VLAN ports. The other standards don’t provide this tagging mechanism: 802.1D is Spanning Tree, 802.3 is the base Ethernet frame format, and 802.11 is Wi‑Fi. So, 802.1Q is the standard that enables tagging for VLANs on a single link.

VLAN tagging on Ethernet frames is defined by 802.1Q. It inserts a 4-byte tag into the frame (placed after the source MAC address) that carries the VLAN ID, enabling multiple VLANs to share a single physical link—this is known as a trunk. Switches use the tag to keep traffic separated by VLAN and forward it only to the matching VLAN ports. The other standards don’t provide this tagging mechanism: 802.1D is Spanning Tree, 802.3 is the base Ethernet frame format, and 802.11 is Wi‑Fi. So, 802.1Q is the standard that enables tagging for VLANs on a single link.

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