STP Recap

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

• To encrypt data during transmission
• To prevent loops in Layer 2 networks
• To assign IP addresses dynamically
• To increase network bandwidth

Answer explanation

STP prevents Layer 2 loops by creating a loop-free topology while maintaining redundancy.

What determines the root bridge in STP?

• The switch with the highest MAC address
• The switch with the lowest Bridge ID
• The switch with the highest priority
• The switch with the most ports

Answer explanation

The root bridge is determined by the lowest Bridge ID, which is a combination of priority and MAC address.

Which STP port state allows a port to forward user traffic?

• Blocking
• Listening
• Learning
• Forwarding

Answer explanation

In the Forwarding state, a port sends and receives user data while maintaining a loop-free topology.

What happens if two switches have the same priority in STP?

• The switch with the highest MAC address wins
• The switch with the lowest MAC address wins
• Both switches become root bridges
• STP disables both switches

Answer explanation

If priorities are equal, STP uses the MAC address as a tiebreaker. The switch with the lowest MAC address becomes root.

Why does STP block certain ports in a redundant network?

• To increase bandwidth on active links
• To prevent Layer 2 loops from forming
• To disable unused ports
• To prioritize VLAN traffic

Answer explanation

STP blocks redundant links to prevent Layer 2 loops while ensuring redundancy for failover scenarios.