JNCIS-ENT: Juniper Networks Certified Specialist – Enterprise Routing and Switching (2024) — Question 3

Your network is configured with dynamic ARP inspection (DAI) using the default parameters for all the DHCP and ARP related configurations. You just added a new device connected to a trunk port and configured it to obtain an IP address using DHCP.
Which two statements are correct in this scenario? (Choose two.)

Answer options

• A. The DHCP server assigns the IP addressing information to the new device.
• B. DAI validates the ARP packets for the new device against the DHCP snooping database.
• C. The ARP request and response packets for the new device will bypass DAI.
• D. DHCP snooping adds the DHCP assigned IP address for the new device to its database.

Correct answer: A, C

Explanation

The correct answer A is valid because the DHCP server is responsible for assigning IP addressing information to devices on the network. Option C is also correct since DAI does not inspect ARP packets when they are generated by a device that has not yet been validated through DHCP snooping. Options B and D are incorrect because DAI would not validate ARP packets for a device that hasn’t been added to the DHCP snooping database, and DHCP snooping does not add the IP address until the device is validated.