What problem does the Spanning Tree Protocol (STP) solve?

What problem does the Spanning Tree Protocol (STP) solve?

• A. Prevents Layer 2 loops by creating a loop-free topology
• B. Prevents IP routing loops
• C. Increases path costs
• D. Encrypts data on the link

Answer: (A)

STP prevents Layer 2 loops by creating a loop-free topology. In a network of switches with multiple redundant links, frames can circulate endlessly if there’s a cycle, causing broadcast storms and unstable MAC tables. STP designates a root bridge and uses bridge protocol data units to determine the best path to the root for every switch. It then blocks the redundant links that would form loops, leaving a single active path tree. If a link fails, STP can unblock a previously blocked path to maintain connectivity, preserving redundancy. This function operates at Layer 2, not at the IP routing layer, and it doesn’t involve encryption. Path costs are used to help build the tree, but the goal is a loop-free topology rather than simply increasing costs.

STP prevents Layer 2 loops by creating a loop-free topology. In a network of switches with multiple redundant links, frames can circulate endlessly if there’s a cycle, causing broadcast storms and unstable MAC tables. STP designates a root bridge and uses bridge protocol data units to determine the best path to the root for every switch. It then blocks the redundant links that would form loops, leaving a single active path tree. If a link fails, STP can unblock a previously blocked path to maintain connectivity, preserving redundancy. This function operates at Layer 2, not at the IP routing layer, and it doesn’t involve encryption. Path costs are used to help build the tree, but the goal is a loop-free topology rather than simply increasing costs.