Which VLAN trunking tagging standard is commonly used on inter-switch links?

Which VLAN trunking tagging standard is commonly used on inter-switch links?

• A. 802.1D
• B. 802.1Q
• C. 802.3
• D. 802.11

Answer: (B)

VLAN tagging on inter-switch links relies on a standard method to carry traffic from multiple VLANs over a single physical connection. The standard that defines how frames are tagged with a VLAN identifier is IEEE 802.1Q. It inserts a 4-byte tag into the Ethernet frame, after the source MAC address, that carries the VLAN ID and optional quality bits. This tagging lets switches know which VLAN each frame belongs to as it traverses the trunk, enabling multiple VLANs to share one link without confusion. Frames for the native VLAN are sent untagged on the trunk, and at the far end the tag is removed before delivering to the destination host. The other options relate to different technologies: 802.1D is the Spanning Tree Protocol, which prevents loops; 802.3 is the basic Ethernet framing and collision domain rules; and 802.11 is the wireless LAN standard. While there are variations and refinements, 802.1Q is the widely used tagging standard for VLANs on inter-switch links.

VLAN tagging on inter-switch links relies on a standard method to carry traffic from multiple VLANs over a single physical connection. The standard that defines how frames are tagged with a VLAN identifier is IEEE 802.1Q. It inserts a 4-byte tag into the Ethernet frame, after the source MAC address, that carries the VLAN ID and optional quality bits. This tagging lets switches know which VLAN each frame belongs to as it traverses the trunk, enabling multiple VLANs to share one link without confusion. Frames for the native VLAN are sent untagged on the trunk, and at the far end the tag is removed before delivering to the destination host. The other options relate to different technologies: 802.1D is the Spanning Tree Protocol, which prevents loops; 802.3 is the basic Ethernet framing and collision domain rules; and 802.11 is the wireless LAN standard. While there are variations and refinements, 802.1Q is the widely used tagging standard for VLANs on inter-switch links.