N10-009 Exam Dumps - CompTIA Network+ Certification Exam

MAC flooding overwhelms a switch’s CAM (Content Addressable Memory) table by sending a flood of frames with spoofed MAC addresses. Once the CAM table overflows, the switch cannot learn legitimate MAC addresses and defaults to flooding all frames out all ports, effectively turning it into a hub. This allows an attacker to capture traffic not originally destined for their port.

A. ARP poisoning corrupts ARP tables to redirect traffic but does not overflow the CAM table.

B. Evil twin is a wireless rogue AP attack, unrelated to switch behavior.

D. DNS spoofing redirects domain queries, not Layer 2 switching.

References (CompTIA Network+ N10-009):

Domain: Network Security — Switch security, CAM table attacks, MAC flooding.

The correct answer is Switch because the question references a new logical layout segmenting the network using tagging, which indicates VLAN (Virtual Local Area Network) configuration. VLAN tagging (IEEE 802.1Q) is performed on switches to logically separate broadcast domains within the same physical infrastructure.

According to CompTIA Network+ (N10-009) objectives under switching technologies, VLANs are used to improve security, reduce broadcast traffic, and logically segment network traffic. When VLAN tagging is misconfigured—such as incorrect trunk ports, access port assignments, or mismatched VLAN IDs—devices may lose connectivity to required network resources.

Since the issue began after changes involving tagging, the most likely cause is an incorrect switch configuration, such as improper VLAN assignments or trunking settings.

An access point (Option A) may use VLANs for SSID segmentation, but core tagging configuration is handled at the switch. A firewall (Option B) filters traffic but does not control VLAN tagging at Layer 2 in typical deployments. A load balancer (Option D) distributes traffic among servers and is unrelated to VLAN segmentation.

Therefore, reviewing the switch configuration is the appropriate action to restore connectivity.

In a split-tunnel VPN, only corporate traffic is sent through the VPN tunnel, while public internet traffic goes directly through the user’s local ISP. This reduces bandwidth use on the corporate VPN concentrator and improves performance for non-work traffic.

B. Separate tunnels for encrypted traffic describes multi-tunnel VPNs, not split tunneling.

C. All traffic routed through on-site servers is a full-tunnel VPN, not split-tunnel.

D. ACLs balancing traffic relates to routing or load balancing, not VPN split tunneling.

References (CompTIA Network+ N10-009):

Domain: Networking Concepts — VPN types, split vs. full tunnel, remote access.

nmap (Network Mapper) is the best tool in this scenario. It can scan the 192.168.1.0/24 subnet to discover live hosts, open ports (like Telnet on port 23), and device types. It’s ideal for mapping and auditing the network.

A. dig is a DNS lookup tool; not useful for identifying hosts on a subnet.

C. tracert shows the path packets take to a destination, not for host discovery.

D. telnet is the protocol being used, not a tool for scanning or identifying devices.

📘 Reference:

CompTIA Network+ N10-009 Official Objectives: 5.1 – Given a scenario, use the appropriate network troubleshooting tools.

Definition of Heat Maps:

A heat map is a graphical representation of data where individual values are represented by colors. In the context of wireless networking, a heat map shows the wireless signal strength in different areas of a building.

Purpose of a Heat Map:

Heat maps are used to illustrate the effectiveness of wireless networking coverage, identify dead zones, and optimize the placement of access points (APs) to ensure adequate coverage and performance.

Comparison with Other Options:

Logical Diagram: Represents the logical connections and relationships within the network.

Layer 3 Network Diagram: Focuses on the routing and IP addressing within the network.

Service-Level Agreement (SLA): A contract that specifies the expected service levels between a service provider and a customer.

Creation and Use:

Heat maps are created using specialized software or tools that measure wireless signal strength throughout the building. The data collected is then used to generate a visual map, guiding network administrators in optimizing wireless coverage.

The most likely issue is a duplex mismatch, which is a well-documented cause of collisions and poor network performance, as outlined in the CompTIA Network+ N10-009 troubleshooting objectives. A duplex mismatch occurs when one end of a network link is configured for full duplex while the other end is operating in half duplex. In half-duplex mode, devices must take turns transmitting and receiving data, which inherently allows for collisions. When paired with a full-duplex device—which expects simultaneous send and receive—collisions and retransmissions occur frequently.

The presence of collisions on a switch interface is a key diagnostic clue. Modern Ethernet switches operating correctly in full duplex should not experience collisions at all. When collisions are observed, it almost always points to a duplex configuration issue, often caused by manual speed/duplex settings on one device and auto-negotiation on the other.

A wrong speed setting may prevent link establishment entirely or cause errors, but it does not typically result in collisions. Jumbo frames can cause packet drops or fragmentation issues, not collisions. An incorrect VLAN configuration affects logical segmentation and connectivity but operates at Layer 2 and does not generate collisions.

CompTIA Network+ emphasizes duplex mismatch as a classic and frequently tested troubleshooting scenario. Correcting it—usually by enabling auto-negotiation on both ends—restores normal, collision-free communication.

Unshielded cables (D) are more prone to interference and may not be suitable for certain environments, especially after a fire where interference could be heightened.

Using the wrong transceiver (E) for new terminations can lead to compatibility issues, causing network failures.

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