Cisco ENCOR Practice Exam 2025 – All-in-One Comprehensive Guide to Mastering Enterprise Network Core Technologies!

A Backup Port in Rapid Spanning Tree Protocol (RSTP) is specifically defined by its role during situations where two redundant connections exist between the same two devices. It is essential to understand that a Backup Port is an additional path that is activated during multiple connections; it stands by to take over should the primary connection fail.

When two switches are connected by more than one cable, RSTP designates one of these ports as the primary active path for forwarding traffic, while the other port becomes the Backup Port. The Backup Port does not engage in forwarding traffic under normal circumstances but is ready to act if there is a failure in the primary connection. This situation ensures there is minimal interruption to the network traffic, as the Backup Port can quickly transition to a forwarding state if necessary.

The other options do not accurately depict the unique characteristics of a Backup Port. A port that connects to the root switch is a description of a designated port, and traffic serving specific VLANs does not pertain exclusively to Backup Ports, as those can occur on a different layer of the network architecture. Lastly, while primary paths for data traffic are crucial for overall functionality, the Backup Port specifically exists to serve as a failover mechanism, not as a primary traffic path.