Which Ethernet feature allows for connected devices to communicate through multiple VLANs?

Trunking is the feature that enables connected devices to communicate through multiple VLANs (Virtual Local Area Networks). It works by allowing a single physical link to carry traffic for multiple VLANs simultaneously. This is typically accomplished through the use of tagging protocols such as IEEE 802.1Q, which adds a tag to the Ethernet frames to identify the VLAN to which the frame belongs.

When trunking is implemented, devices can segment and separate their broadcast domains while still using the same physical infrastructure. This capability greatly enhances network efficiency by reducing the number of physical links needed to connect VLANs and allows for improved resource utilization. Each VLAN can maintain its own traffic characteristics, which provides flexibility in managing network resources and policies.

This architecture is essential in environments where network segmentation is needed, such as in large enterprises, as it allows for better management of traffic flows and can enhance security by isolating network segments.