What is the main purpose of the STP protocol?

The Spanning Tree Protocol (STP) is primarily designed to prevent network loops in Layer 2 Ethernet networks. Network loops can occur when there are multiple active paths between switches, causing broadcast storms, multiple frame copies, and ultimately network congestion and failure. STP works by identifying redundant paths and selectively blocking some of them to ensure there is only one active path between any two network devices at any time. This not only stabilizes the network but also enables reliable data transmission.

The other options focus on different network concerns. Enhancing network security is typically managed through protocols like 802.1X or access control lists rather than STP. Boosting signal strength falls under physical layer concerns like repeaters or amplifiers, while managing IP addressing involves protocols such as DHCP or static routing, which are unrelated to the functions of STP.