CompTIA N10-009 - CompTIA Network+ Certification Exam

GSM (Global System for Mobile communications) is the international standard that uses SIM cards to authenticate and connect phones to the cellular network. GSM allows users to place and receive calls while traveling globally, provided they have a SIM card. CDMA, on the other hand, does not use SIM cards in the same way and is primarily used in the United States. (Reference: CompTIA Network+ Study Guide, Chapter on Network Fundamentals)

Definition of SD-WAN:

Software-Defined Wide Area Network (SD-WAN) is a technology that simplifies the management and operation of a WAN by decoupling the networking hardware from its control mechanism. It allows for centralized management and enhanced security.

Benefits of SD-WAN:

Reduced Provisioning Time: SD-WAN enables quick and easy deployment of new sites with centralized control and automation.

Security: Incorporates advanced security features such as encryption, secure tunneling, and integrated firewalls.

Scalability: Easily scales to accommodate additional sites and bandwidth requirements.

Comparison with Other Technologies:

VXLAN (Virtual Extensible LAN): Primarily used for network virtualization within data centers.

VPN (Virtual Private Network): Provides secure connections but does not offer the centralized management and provisioning efficiency of SD-WAN.

NFV (Network Functions Virtualization): Virtualizes network services but does not specifically address WAN management and provisioning.

Implementation:

SD-WAN solutions are implemented by deploying edge devices at each site and connecting them to a central controller. This allows for dynamic routing, traffic management, and security policy enforcement.

Private VLANs (PVLANs) are used to segment devices on the same subnet and switch so they cannot communicate with each other, while still accessing a shared resource like a router or gateway. This is often used in shared hosting or DMZ environments.

A. ACLs (Access Control Lists) control traffic between networks, not within the same VLAN.

B. Trunking carries multiple VLANs between switches but does not isolate devices.

C. Port security limits MAC addresses per port but doesn’t isolate communication between ports.

📘 Reference:

CompTIA Network+ N10-009 Official Objectives: 3.4 – Compare and contrast access control methods.

A mesh network is the best solution for providing reliable wireless service to public safety vehicles. In a mesh network, each node (vehicle) can connect to multiple other nodes, providing multiple paths for data to travel. This enhances reliability and redundancy, ensuring continuous connectivity even if one or more nodes fail. Mesh networks are highly resilient and are well-suited for dynamic and mobile environments such as public safety operations.References: CompTIA Network+ study materials.

When working with fiber optic cables, one common issue is that the transmit (TX) and receive (RX) fibers might be reversed. The first step in troubleshooting should be to reverse the fibers at one end to ensure they are correctly aligned (TX to RX and RX to TX). This is a simple and quick step to rule out a common issue before moving on to more complex troubleshooting.References: CompTIA Network+ study materials.

When deploying multiple Power over Ethernet (PoE) devices, the switch’s power budget can be exhausted. If the available wattage on the switch cannot supply the additional AP, it will fail to power on. This is the most likely cause when previous APs worked fine but a new one does not.

A. Signal strength affects wireless connectivity, not whether the AP powers up.

B. Duplex mismatch causes poor throughput, not power failure.

D. CRC errors point to cabling issues but do not prevent booting if no power is available.

References (CompTIA Network+ N10-009):

Domain: Network Troubleshooting — PoE power budget considerations, device startup issues.

Quality of Service (QoS): This is a feature used in networking to prioritize certain types of traffic. By configuring QoS, network administrators can allocate higher bandwidth to time-sensitive applications like VoIP, video conferencing, or critical business applications during peak usage times. This helps to reduce latency and packet loss, which are often caused by congestion.

Load Balancing (A): While load balancing is useful in distributing traffic across multiple servers or paths, it does not address congestion on a single switch.

Port Mirroring (B): This is used for monitoring network traffic for troubleshooting and diagnostics but does not alleviate congestion.

Spanning Tree Protocol (D): STP prevents switching loops in redundant network topologies, but it is not designed to handle traffic prioritization or congestion issues.

Changing the default password is a fundamental step in device hardening, as default credentials are widely known and published online, posing a significant security risk if not updated. The document notes:

“Default passwords are often known by attackers and published on the internet. Changing them to unique, strong passwords is a critical first step in securing network devices against unauthorized access.”

The correct solution is NTP (Network Time Protocol). Accurate timestamps across servers, firewalls, and network devices are critical for correlating logs during incident response. NTP synchronizes device clocks to a trusted time source, ensuring consistency across the network.

A. Syslog centralizes logs but does not synchronize time.

B. SMTP is email transfer, unrelated to time.

D. SNMP monitors devices but does not correct time discrepancies.

By implementing NTP, analysts can ensure that logs from different devices are time-aligned, which is essential for reconstructing attack timelines and detecting anomalies.

References (CompTIA Network+ N10-009):

Domain: Network Operations — Time synchronization, NTP, log correlation.