What is the primary function of the Spanning Tree Protocol (STP)?

The primary function of the Spanning Tree Protocol (STP) is to prevent loops in Ethernet networks. In a network with multiple interconnected switches, the risk of creating loops can lead to broadcast storms and network instability. STP ensures that only one logical path exists between any two network devices by selectively blocking redundant paths. This protocol listens for the topology of the network, elects a root bridge, and then identifies and disables any redundant links that could cause loops. By maintaining a loop-free topology, STP helps ensure data packets are delivered efficiently and prevents the overwhelming of network resources, maintaining the overall stability and reliability of the network.