Designing Cisco Enterprise Networks (ENSLD) — Question 297

An engineer is designing a network for a customer running a wireless network with a common VLAN for all APs. The customer is experiencing unicast flooding in the Layer 2 network between the aggregation and access layers. The customer wants to reduce the flooding and improve convergence time. Which solution meets these requirements?

Answer options

• A. Migrate all APs to a common Layer 2 access layer switch and run Layer 3 from the aggregation layer to all remaining access layer switches.
• B. Align HSRP primary and STP root bridges and reduce ARP timers to match CAM timers on the aggregation layer switches.
• C. Migrate to a Layer 3 access campus design if the APs can run on separate VLANs.
• D. Align HSRP primary and STP root bridges if the APs cannot run on separate VLANs.

Correct answer: B

Explanation

Option B is correct because aligning HSRP primary and STP root bridges, along with reducing ARP timers, can effectively reduce flooding and enhance convergence time. Option A does not address the flooding issue adequately as it consolidates APs but does not improve Layer 2 handling. Option C suggests a transition to Layer 3, which may not be possible if the APs need to operate on the same VLAN, and option D is only applicable if separate VLANs are not an option.