What does the Spanning Tree Protocol primarily prevent in a network?

• A. Spanning Tree Protocol; it prevents loops and broadcast storms.
• B. It assigns IP addresses automatically.
• C. It encrypts data on the link.
• D. It optimizes routing via OSPF metrics.

Answer: (A)

Spanning Tree Protocol prevents switching loops in Ethernet networks. When multiple switches are interconnected with redundant links, a loop can cause frames to circulate endlessly, creating broadcast storms that waste bandwidth and overwhelm devices. STP builds a loop-free tree by electing a root bridge, determining the best paths to each segment, and placing some ports into a blocking state so only one active path exists between any two devices. If a chosen path fails, blocked ports can be re-enabled to restore connectivity, preserving both safety and resilience. This is not about automatic IP assignment, link encryption, or routing metric optimization, which are handled by other technologies.