What is the default behavior of a trunk port when it receives transit traffic without a VLAN tag?
A.
It drops the traffic.
B.
It forwards the traffic.
C.
It tags the transit traffic with lowest VLAN ID permitted on the trunk.
D.
It tags the transit traffic with highest VLAN ID permitted on the trunk.
Explanation:
To identify which VLAN the traffic belongs to, all frames on an Ethernet VLAN are identified by a tag, as defined in the IEEE 802.1Q standard.
These frames are tagged and are encapsulated with 802.1Q tags.For a simple network that has only a single VLAN, all traffic has the same 802.1Q tag. When an Ethernet LAN is divided into VLANs, each VLAN is identified by a unique 802.1Q tag. The tag is applied to all frames so that the network nodes receiving the frames know to which VLAN a frame belongs. Trunk ports, which multiplex traffic among a number of VLANs, use the tag to determine to origin of frames and where to forward them.
When a port is tagged, it allows communication among the different VLANs to which it is assigned. A common use for this might be to place an email server that multiple groups may need access to on a tagged port, which in turn, is resident in all VLANs that need access to the server.
NOTE: Tagging does not apply to the default VLAN.