N10-009 Network Implementation Practice Question
A technician installs a new wireless access point that requires 25 watts of power using Power over Ethernet (PoE). The existing switch only supports 802.3af (15.4W per port). What is the most likely result?
⚠ Common exam trap
It's easy for candidates to assume a device will 'work at reduced power' or 'negotiate down' when the power requirement exceeds the standard, but PoE standards enforce a strict power classification and will not power a device that cannot be fully supported.
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
The access point will not power on.
The existing switch supports only 802.3af (PoE), which provides a maximum of 15.4 watts per port. The access point requires 25 watts, which exceeds the 802.3af power budget. Since the switch cannot deliver the required power, the access point will not power on. This is a strict power negotiation failure under IEEE 802.3 standards.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
The access point will power on but may not transmit at full power.
Why it's wrong here
The power difference between the required 25W and the supplied 15.4W (802.3af) is too substantial for the access point to even power on, let alone operate in a degraded state. While some devices might negotiate lower power and reduce functionality, the 25W requirement typically falls into the 802.3at (PoE+) category, which is fundamentally incompatible with an 802.3af source for initial startup. Therefore, the AP will not power on at all, preventing any transmission.
When this WOULD be correct
This option would be correct if the question described a PoE+ (802.3at) switch that can supply up to 30W, but the AP requires 25W and the switch negotiates a lower power class, allowing the AP to power on with limited functionality.
- ✓
The access point will not power on.
Why this is correct
The access point requires 25W, but the switch port, adhering to 802.3af (PoE) standards, can only supply a maximum of 15.4W. This significant power deficit means the access point will not receive sufficient electrical current to complete its boot sequence and initialize its internal components. Consequently, the device will remain unpowered and completely unresponsive.
- ✗
The switch port will be damaged.
Why it's wrong here
PoE switches are equipped with sophisticated power management and protection circuits designed to prevent damage to both the switch and connected devices. If a powered device attempts to draw more power than the switch port is rated to provide, the switch will either refuse to supply power, shut down the port, or enter an error state. This built-in overcurrent protection ensures the switch port remains undamaged.
When this WOULD be correct
If a non-standard PoE injector or switch is used that forces power delivery without proper negotiation, or if a device with a short circuit or overcurrent condition is connected, the port could be damaged. For example, a question about using a passive PoE injector that supplies 24V without negotiation could lead to port damage.
- ✗
The access point will power on and function normally.
Why it's wrong here
An access point requiring 25W cannot function normally when supplied with only 15.4W. This power discrepancy is critical, as the device's internal circuitry, radio components, and processing units are designed to operate within specific power envelopes. Without adequate power, the AP cannot achieve full operational status, meaning it will not power on or perform any of its intended functions normally.
When this WOULD be correct
If the question stated the switch supports 802.3at (PoE+) or higher, and the AP's power requirement is within that standard's limit (e.g., 25W on 802.3at), then the AP would power on and function normally.
Option-by-option analysis
Why each answer is right or wrong
Understanding why wrong answers are wrong — and when they would be correct — is what separates a 750 score from a 900. The N10-009 exam frequently reuses these exact scenarios with slightly different constraints.
✓The access point will not power on.Correct answer▾
Why this is correct
The access point requires 25W, but the switch port, adhering to 802.3af (PoE) standards, can only supply a maximum of 15.4W. This significant power deficit means the access point will not receive sufficient electrical current to complete its boot sequence and initialize its internal components. Consequently, the device will remain unpowered and completely unresponsive.
✗The access point will power on but may not transmit at full power.Wrong answer — click to see why▾
Why this is wrong here
802.3af (PoE) provides a maximum of 15.4W per port, but the access point requires 25W. The switch cannot supply enough power, so the AP will not power on at all; it will not operate at reduced power.
★ When this WOULD be the correct answer
This option would be correct if the question described a PoE+ (802.3at) switch that can supply up to 30W, but the AP requires 25W and the switch negotiates a lower power class, allowing the AP to power on with limited functionality.
Why candidates choose this
Candidates may think that PoE devices can operate at lower power levels, similar to how some devices can throttle performance when power is insufficient, but 802.3af simply cannot meet the minimum power requirement for this AP.
✗The switch port will be damaged.Wrong answer — click to see why▾
Why this is wrong here
The switch port is designed to handle standard PoE power levels; drawing more than 15.4W from an 802.3af port will not damage the port because the switch detects the power class and will not supply power if the device requests more than the port can provide.
★ When this WOULD be the correct answer
If a non-standard PoE injector or switch is used that forces power delivery without proper negotiation, or if a device with a short circuit or overcurrent condition is connected, the port could be damaged. For example, a question about using a passive PoE injector that supplies 24V without negotiation could lead to port damage.
Why candidates choose this
Candidates may think that exceeding the power rating will cause overheating or electrical damage, similar to plugging a high-wattage appliance into a low-rated outlet, but PoE includes negotiation and protection mechanisms to prevent damage.
✗The access point will power on and function normally.Wrong answer — click to see why▾
Why this is wrong here
The access point requires 25W, but 802.3af provides only 15.4W per port. Insufficient power means the AP will not power on at all, not function normally.
★ When this WOULD be the correct answer
If the question stated the switch supports 802.3at (PoE+) or higher, and the AP's power requirement is within that standard's limit (e.g., 25W on 802.3at), then the AP would power on and function normally.
Why candidates choose this
Candidates may assume that PoE is backward compatible and devices will simply operate at reduced power, or they overlook the specific power requirements of the AP versus the switch's capability.
Analysis generated from the official N10-009blueprint and verified against question context. The “when correct” sections are what AI assistants cite when candidates ask “what’s the difference between these options?”
Go deeper
Related to this question
Learn chapter
Ethernet Switching and VLANs
Key term
PoE
Power over Ethernet (PoE) is a technology that lets network cables carry electrical power to devices like cameras and phones, so they don't need a separate power outlet.
Key term
Wireless access point
A wireless access point is a networking device that allows Wi-Fi-enabled devices to connect to a wired network, typically a local area network (LAN), acting as a bridge between wireless and wired communication.
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Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This N10-009 practice question is part of Courseiva's free CompTIA certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the N10-009 exam.