CompTIA Network+ Practice Test

What does the blocking state do in the STP port state?

1. Forwards data to prevent loops

2. Passively listens for network traffic

3. Prevents data forwarding to avoid loops

4. Updates MAC addresses in the table

The correct answer is: Prevents data forwarding to avoid loops

In the Spanning Tree Protocol (STP), the blocking state is crucial for maintaining network stability and preventing loops within a switched network topology. When a port is in the blocking state, it actively prevents data frames from being forwarded through that port. This ensures that any potential loops are eliminated, which could lead to broadcast storms and subsequently degrade network performance. The blocking state is part of the overall STP port states, which include listening, learning, and forwarding. By keeping certain ports blocked, STP ensures that only one active path exists between any two switches in the network, effectively managing redundancy. In contrast, other port states serve different functions. For instance, the forwarding state allows for data to traverse normally, while the listening state prepares to ensure that no loops occur before the port begins to transition to the learning state. In summary, the blocking state is essential for loop prevention by stopping data transmissions, thereby maintaining an efficient and stable network environment.