CompTIA Updated N10-009 Exam Questions and Answers by moshe

Power over Ethernet (PoE) allows devices such as cameras, access points, and VoIP phones to receive both power and data over the same Ethernet cable. If only eight out of twelve cameras turn on, the most likely issue is that the PoE switch has exceeded its power budget (total wattage capacity).

PoE Budget Limitation: PoE switches have a maximum power output, which can limit the number of devices they support simultaneously.

Voltage Check: Different PoE standards exist:

802.3af (PoE): Supplies up to 15.4W per port

802.3at (PoE+): Supplies up to 30W per port

802.3bt (PoE++): Supplies up to 60-100W per port

Power Draw Calculation: If each camera requires 15W and the switch can only provide 120W, then only 8 cameras (8 × 15W = 120W) will turn on.

Incorrect Options:

A. Ethernet Cable Type: Most PoE devices work with Cat5e and above. Cable type could be an issue, but power limitation is the more immediate concern.

C. Transceiver Compatibility: Only relevant if fiber transceivers or modules are in use, but not likely the root cause for power-related issues.

D. DHCP Addressing: DHCP issues affect network connectivity, not power delivery.

The 802.11n standard supports MIMO (Multiple Input Multiple Output), which allows multiple antennas to increase data throughput and improve reliability. Additionally, it uses non-overlapping channels in the 5 GHz band (and optionally the 2.4 GHz band), making it a good choice for high-speed, interference-resistant wireless connections. (Reference: CompTIA Network+ Study Guide, Chapter on Wireless Technologies)

A signal power of -97dB indicates a very weak signal, which can cause connectivity issues and slow speeds. Splitters on a coaxial line can degrade the signal quality further, so removing them can help improve the signal strength and overall connection quality.

Signal Quality: Splitters can reduce the signal strength by dividing the signal among multiple lines, which can be detrimental when the signal is already weak.

Direct Connection: Ensuring a direct connection from the modem to the incoming line can maximize signal quality and reduce potential points of failure.

Network References:

CompTIA Network+ N10-007 Official Certification Guide: Discusses troubleshooting connectivity issues and the impact of signal strength on network performance.

Cisco Networking Academy: Provides insights on maintaining optimal signal quality in network setups.

Network+ Certification All-in-One Exam Guide: Covers common network issues, including those related to signal degradation and ways to mitigate them.

When installing multiple Power over Ethernet (PoE) devices like security cameras, it is crucial to ensure that the total power requirement does not exceed the power budget of the PoE switch. Each PoE switch has a maximum power capacity, and exceeding this capacity can cause some devices to fail to receive power.

PoE Standards: PoE switches conform to standards such as IEEE 802.3af (PoE) and 802.3at (PoE+), each with specific power limits per port and total power capacity.

Power Calculation: Adding up the power requirements of all connected PoE devices can help determine if the total power budget of the switch is exceeded.

Symptoms: When the power budget is exceeded, some devices, typically those farthest from the switch or connected last, may not power up or function correctly.

Network References:

CompTIA Network+ N10-007 Official Certification Guide: Covers PoE standards and troubleshooting power issues.

Cisco Networking Academy: Discusses PoE technologies, power budgeting, and managing PoE devices.

Network+ Certification All-in-One Exam Guide: Provides information on PoE setup, including power budget considerations.