300-420 Question 101
Select 4A network engineer is designing a new enterprise LAN that will support Wake-on-LAN (WoL) functionality for desktop computers across multiple floors. The network switches will also provide Power over Ethernet (PoE) to various devices such as IP phones and wireless access points. What design considerations must the engineer account for to ensure both WoL and PoE function correctly?
- A
Ensure that the switches support sufficient PoE power budgets to handle all connected devices.
- B
Enable WoL-specific packet forwarding on switches to ensure Magic Packets can traverse the network.
- C
Deploy switches that support IEEE 802.3af for PoE and WoL functionality.
- D
Ensure that broadcast traffic, including Magic Packets, is allowed across VLANs if WoL is required between different subnets.
- E
Configure PoE to prioritize power delivery to devices with critical functions, such as IP phones, during power budget constraints.
Show answer and explanation
Correct answers: A, B, D, E
Explanation
To successfully implement both PoE and WoL in an enterprise network, the engineer must ensure switches have adequate PoE power budgets, properly configure the network to forward WoL Magic Packets, and account for VLAN or subnet boundaries for WoL. Additionally, PoE prioritization ensures critical devices receive power during constraints. IEEE 802.3af defines PoE standards but does not address WoL functionality, so additional configurations are necessary for Wake-on-LAN support.
- A. Correct.
Correct. Switches must have adequate PoE power budgets to meet the power requirements of connected devices, ensuring uninterrupted operation of devices such as IP phones and access points.
- B. Correct.
Correct. WoL functionality depends on Magic Packets reaching the intended device, so switches must support WoL-specific packet forwarding or ensure multicast/broadcast traffic is handled appropriately.
- C. Incorrect.
Incorrect. While IEEE 802.3af defines PoE standards, it does not inherently support WoL functionality. WoL requires additional considerations, such as Magic Packet forwarding.
- D. Correct.
Correct. If WoL is required across VLANs, the network must allow broadcast or directed broadcast traffic for Magic Packets to reach the destination. This requires proper VLAN and routing configurations.
- E. Correct.
Correct. Configuring PoE prioritization ensures that critical devices, such as IP phones, receive power during power budget constraints, which is important in a well-designed enterprise network.