What is the first step in the Spanning Tree Protocol (STP) operation?

The first step in the operation of the Spanning Tree Protocol (STP) is the exchange of Bridge Protocol Data Units (BPDUs) between switches. This initial communication is crucial as it allows switches to share information about their bridge IDs and establish a topology.

When STP is activated, each switch sends out BPDUs to announce its presence and gather information about other switches in the network. This process sets the foundation for subsequent steps, including the election of the root bridge and the identification of root and designated ports. Without the exchange of BPDUs, switches would not be able to determine which device should become the root bridge or how to create a loop-free topology within the network.

In summary, the sending of BPDUs is essential for the proper functioning of STP, as it kickstarts the protocol’s mechanism for preventing loops and ensuring efficient data flow.