A switch port is sending both tagged and untagged traffic. What is its possible configuration?

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The scenario describes a switch port that is handling both tagged and untagged traffic, which points to a configuration that can manage both types effectively. The correct configuration would be a port-mode access with a native VLAN ID.

In this context, an access port typically allows traffic for a single VLAN; however, by configuring a native VLAN ID, the port can also handle untagged traffic. The native VLAN is the VLAN that untagged traffic is associated with. When a frame arrives on an access port without a VLAN tag, it is processed as if it belongs to the native VLAN. This allows for flexibility in environments where both tagged and untagged traffic are common.

Having a native VLAN effectively accommodates devices that may only send untagged traffic while still allowing for proper VLAN segregation for tagged traffic. Therefore, option C correctly describes a setup that can manage mixed traffic types on a switch port.

In contrast, other configurations such as port-mode trunk do allow for both tagged and untagged traffic but typically in a different context, as they are designed to facilitate multiple VLANs simultaneously rather than focus on a single, untagged VLAN. The port-mode access with no VLAN configuration would not support any tagged traffic, making it unfit for