Cisco Certified Network Associate (CCNA) Practice Exam

What is the configurable time range for the BPDU timer in STP?

1. 0 - 5 seconds

2. 1 - 10 seconds

3. 5 - 20 seconds

4. 1 - 15 seconds

The correct answer is: 1 - 10 seconds

The correct choice regarding the configurable time range for the Bridge Protocol Data Unit (BPDU) timer in Spanning Tree Protocol (STP) is based on the defined behavior of BPDU transmission intervals. In STP, BPDUs are used to maintain a loop-free environment in a network by allowing switches to identify and eliminate redundant paths. The timer for sending BPDUs is typically set to 2 seconds by default in a typical STP configuration. However, within the context of this question, the option that best reflects the configurability of this timer is indeed between 1 and 10 seconds. This range allows for a deviation in BPDU transmission timing while still ensuring timely updates to the network topology, thus preventing loops and maintaining the integrity of the data path. By having this configurable range, network administrators can fine-tune STP behavior based on the specific needs of their network, considering factors like network size, topology changes, and latency requirements. This configurability is essential for optimizing STP performance and ensuring that all switches in the network can react appropriately to changes in topology.