CompTIA Updated N10-009 Exam Questions and Answers by aasiyah

MTTR (Mean Time to Repair) is the average time it takes to repair a system or service after a failure. It helps in measuring the downtime and planning recovery processes.

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The correct answer is STP (Shielded Twisted Pair). According to the CompTIA Network+ N10-009 objectives, environments with high levels of electromagnetic interference (EMI)—such as industrial warehouses with heavy machinery, motors, and electrical equipment—require additional protection at the physical layer to maintain signal integrity.

STP cabling includes shielding around the twisted copper pairs that helps block external electromagnetic signals from interfering with data transmission. This shielding significantly reduces crosstalk and EMI, making STP far more suitable than UTP (Unshielded Twisted Pair) in electrically noisy environments. UTP lacks this shielding and is more prone to signal degradation under such conditions.

While fiber-optic cabling (multimode or single-mode) is completely immune to EMI, it is typically not used to directly connect wireless APs in most enterprise deployments. Wireless access points commonly rely on copper Ethernet connections to support Power over Ethernet (PoE), which supplies both data and electrical power over the same cable. Fiber does not natively support PoE, making it impractical for directly powering APs without additional equipment.

The Network+ objectives emphasize selecting appropriate cabling based on environmental factors and operational requirements. In this scenario, STP provides the optimal balance of EMI resistance, Ethernet compatibility, and PoE support, making it the best choice for connecting APs in an industrial warehouse.

Comprehensive and Detailed Explanation (paraphrased, aligned to N10-009):

In a spine–leaf architecture, endpoints (including servers, firewalls, and WAN/edge routers) connect to leaf switches. Leaf switches then uplink to spine switches; spine switches do not have endpoints connected directly to them. Therefore, a WAN router (an external/edge device) should connect to the leaf layer—often specifically to a “border leaf” that handles external connectivity.

Why not B. Core or D. Spine? In spine–leaf, “core” isn’t a formal layer, and spines are designed only to interconnect leafs, not to terminate endpoints.

Why not A. Access? “Access” is a term from the traditional three-tier model (access–distribution–core). In modern spine–leaf language, the analogous layer for endpoint attachment is the leaf.

References (CompTIA Network+ N10-009):

Domain: Network Infrastructure — Data center and campus architectures (spine–leaf vs. three-tier), roles of leaf/spine, WAN/edge connectivity points.

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If the company’s SSID is not visible in some areas while other networks are still visible, the most likely cause is insufficient wireless coverage. The wireless signal does not reach those areas, meaning additional access points or signal boosters may be required.

Breakdown of Options:

A. Interference or channel overlap – Would cause slow or unstable connections, but the SSID should still be visible.

B. Insufficient wireless coverage – ✅ Correct answer. If the SSID is not appearing, the signal is too weak in that area.

C. Roaming misconfiguration – Would cause devices to stay on weaker APs instead of switching, but the SSID should still be visible.

D. Client disassociation issues – This would disconnect users, but they should still see the network.