CompTIA Updated N10-009 Exam Questions and Answers by haleema

The correct answer is B. Spanning tree . At the distribution layer, switch redundancy is common because multiple paths are usually built into the design to avoid a single point of failure. The problem with redundant Layer 2 paths is that they can create switching loops, broadcast storms, and unstable MAC address tables if nothing controls them. Spanning Tree Protocol solves that problem by logically blocking one or more redundant paths while still keeping those paths available as backups.

That makes spanning tree the best fit for a feature that supports both redundancy and safe scaling . As the switched environment grows, STP helps maintain a stable topology and prevents loop-related failures. If the active path fails, a blocked redundant path can be brought into service.

The other options do not address the real need. VLAN assignment is used to segment broadcast domains, but it does not manage redundant Layer 2 paths. Port speed only affects throughput on an interface. Full duplex improves communication efficiency on a link, but it also does not provide redundancy control or loop prevention.

When a Network+ question mentions redundancy on switches and asks for the best switching feature, spanning tree is the strongest answer.

Definition of Jumbo Frames:

Jumbo frames are Ethernet frames with more than 1500 bytes of payload, typically up to 9000 bytes. They are used to improve network performance by reducing the overhead caused by smaller frames.

Why Switches Support Jumbo Frames:

Switches are network devices designed to manage data packets and can be configured to support jumbo frames. This capability enhances throughput and efficiency, particularly in high-performance networks and data centers.

Incompatibility of Other Devices:

Access Point: Primarily handles wireless communications and does not typically support jumbo frames.

Bridge: Connects different network segments but usually operates at standard Ethernet frame sizes.

Hub: A simple network device that transmits packets to all ports without distinguishing between devices, incapable of handling jumbo frames.

Practical Application:

Enabling jumbo frames on switches helps in environments where large data transfers are common, such as in storage area networks (SANs) or large-scale virtualized environments.

Multimode fiber optic cables involve the transmission of light signals that bounce off the core ' s cladding as they travel down the fiber. This characteristic differentiates it from single-mode fiber, where the light travels directly down the fiber without reflecting off the cladding.

Here are some detailed points about multimode fiber cables:

Construction: Multimode fibers have a larger core diameter, typically 50 or 62.5 microns, compared to single-mode fibers, which have a core diameter of about 9 microns.

Light Propagation: The larger core of multimode fiber allows multiple light modes to propagate. These modes travel at different angles, leading to reflections off the core-cladding boundary.

Distance and Bandwidth: Due to modal dispersion, where different light modes arrive at the receiver at different times, multimode fibers are suited for shorter distance applications compared to single-mode fibers. Typical distances are up to 550 meters for 10 Gbps Ethernet using OM4 multimode fiber.

Applications: Multimode fibers are commonly used in LANs (Local Area Networks), data centers, and for shorter distance data transmission due to their cost-effectiveness and ease of installation.

Network References:

CompTIA Network+ N10-007 Official Certification Guide, which covers fiber optic technologies, including the differences between multimode and single-mode fibers.

Cisco Networking Academy: Provides training materials and reference guides on the properties of different fiber optic cables.

Fiber Optic Association (FOA): A professional society dedicated to fiber optics, offering extensive information and certification on fiber optic technologies.

Multimode fibers are specifically designed for short-range communication with higher data rates and are typically used in environments like data centers, where high bandwidth over shorter distances is crucial. The reflections off the cladding, inherent to multimode fiber, facilitate this high-capacity communication.

The correct answer is VLSM (Variable Length Subnet Masking). According to the CompTIA Network+ N10-009 objectives, VLSM allows a network administrator to create subnets of different sizes within the same network, making it ideal for environments where subnet host requirements vary.

In this scenario, the technician must support multiple subnet sizes—60 hosts, 15 hosts, and seven hosts—within a single Class C network. Using a single subnet mask for all eight subnets would either waste a large number of IP addresses or fail to meet host requirements. VLSM solves this problem by allowing each subnet to be assigned a custom subnet mask that closely matches its host needs, maximizing address efficiency.

CIDR enables classless addressing and route aggregation but does not, by itself, describe creating multiple subnet sizes within a single address block. APIPA is a self-assigned addressing mechanism used when DHCP fails and has no relevance to subnet design. RFC 1918 defines private IP address ranges but does not address subnetting strategies.

The Network+ objectives emphasize VLSM as a best practice for efficient IP address management, especially in enterprise environments where conserving address space and meeting diverse departmental requirements are critical. In this case, VLSM is the only solution capable of meeting all stated constraints.