In a network using RSTP, which statement about port roles is correct?

In a network utilizing Rapid Spanning Tree Protocol (RSTP), each port on a switch can assume a specific role based on the network topology and the position of the switch within that topology. The alternate port role is specifically used to provide a backup path to the root bridge in case the currently active path fails.

When a port is designated as an alternate port, it means that while it is not forwarding traffic, it is ready to take over if the active path (root port) goes down. This feature allows RSTP to respond quickly to changes in the network, significantly reducing the time required to re-establish a loop-free topology after a link failure.

For a switch like SW2, having its port Gi0/1 in an alternate role implies that this port is not the main forwarding path to the root bridge, but it serves as a potential backup that can immediately take over if the primary path is disrupted. This is crucial to maintaining network reliability and minimizing downtime.

The other roles outlined in the other options provide valid scenarios, but they do not necessarily mean that they must apply in every situation or context. The presence of designated, alternate, blocked, or root ports will vary based on the specific connections and the network's topology. Thus