N10-009 Questions and Answers

A subinterface is a logical interface created on a single physical router interface that allows routing between VLANs (known as Router-on-a-Stick (ROAS)). This method is commonly used when only one physical router is available, allowing inter-VLAN communication without additional hardware.

•Why not the other options?

•VXLAN (B) – This is used for extending Layer 2 networks over a Layer 3 infrastructure, primarily in data centers. It does not directly enable inter-VLAN communication.

•Layer 3 switch (C) – A Layer 3 switch can route between VLANs, but the scenario states that purchasing additional hardware is not an option.

•VIR (D) – This is not a standard networking term in the context of VLAN communication.

Secure Shell (SSH) is a protocol used to securely access remote devices over an unsecured network. It provides encrypted command-line access and is a lightweight and secure method of remote administration.

A. Site-to-site VPN connects entire networks, not just a single host.

B. Telnet is not secure; it transmits data (including credentials) in plaintext.

C. Console access is direct via serial cable, not remote.

???? Reference:

CompTIA Network+ N10-009 Official Objectives: 2.6 – Configure and troubleshoot remote access.

•Too much overlap on the same channel (all devices on channel 11) causes interference, leading to retransmissions and high latency.

•Same SSIDs (A) are expected in mesh networks.

•Device compatibility (C) would show different symptoms.

•Node power (D) affects coverage, not congestion.

????Reference: CompTIA Network+ N10-009 Official Documentation – Wireless Troubleshooting & Signal Interference.

Packet Capture: This method captures and inspects network traffic to identify unauthorized downloads or malicious behavior. It provides detailed insight into the data being transmitted, making it the best tool for this scenario.

Anomaly alerts (A): Alerts may indicate unusual activity but do not provide detailed traffic analysis.

Port mirroring (B): Port mirroring can redirect traffic for analysis but requires a packet capture tool for deeper inspection.

Performance monitoring (C): Focuses on system performance metrics, not detailed traffic content.

The tracert (Traceroute) command is used to determine the path packets take from the source to the destination. It helps in identifying routing issues by showing each hop the packets pass through, along with the time taken for each hop. This command can pinpoint where the connection is failing or experiencing delays, making it an essential tool for troubleshooting routing issues.References: CompTIA Network+ study materials and common network troubleshooting commands. ​

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 most common protocol for secure VPNs is IPsec (Internet Protocol Security). IPsec provides confidentiality, integrity, and authentication for VPN traffic, typically using ESP (Encapsulating Security Payload). It is used in both site-to-site and remote access VPNs.

B. GRE encapsulates traffic but does not provide encryption.

C. BGP is a routing protocol, not a VPN technology.

D. SSH can be used for secure tunneling but is not the standard for VPN deployment.

IPsec is the industry standard because it operates at Layer 3, securing IP traffic regardless of the application, making it highly versatile.

References (CompTIA Network+ N10-009):

Domain: Network Security — VPN protocols, IPsec, ESP.

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

A broadcast message is delivered to all nodes in a broadcast domain (e.g., ARP requests).

A. Unicast is one-to-one.

C. Multicast is one-to-many but only to subscribed members.

D. Anycast is one-to-one-of-many, sending to the nearest node.

References (CompTIA Network+ N10-009):

Domain: Networking Concepts — Traffic types: unicast, multicast, broadcast, anycast.

An SLA (Service Level Agreement) defines performance expectations, including response time, prioritization, and resolution time for services and support issues. It helps the technician determine which task has higher priority based on business impact.

A. NDA (Non-Disclosure Agreement) relates to confidentiality, not task prioritization.

B. AUP (Acceptable Use Policy) defines user behavior, not issue handling.

D. MOU (Memorandum of Understanding) outlines informal agreements and doesn't define ticket priorities.

???? Reference:

CompTIA Network+ N10-009 Official Objectives: 4.1 – Compare and contrast common documentation types.

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.

Since the switch supports only 10Gbps per port, achieving 40Gbps throughput requires link aggregation (LACP), which combines multiple 10Gbps links into one logical interface for higher bandwidth.

Breakdown of Options:

A. 802.1Q tagging – VLAN tagging helps segment traffic but does not increase throughput.

B. Jumbo frames – Jumbo frames reduce overhead but do not increase bandwidth.

C. Half duplex – Half duplex restricts communication, reducing performance instead of improving it.

D. Link aggregation – Correct answer. LACP combines multiple 10Gbps links to provide a 40Gbps connection.

The issue is that no root bridge has been identified. In STP, a root bridge is necessary to manage redundant paths and avoid loops in the network. Without a root bridge, all switches will assume they can forward traffic, causing a network loop and connectivity problems.

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BNC connectors are commonly used for coaxial cables, including those connecting to external antennas in Wi-Fi, radio, and surveillance systems.

Breakdown of Options:

A. BNC – Correct answer. Used for coaxial cables in wireless and antenna connections.

B. ST – Used for fiber optic cables, not antennas.

C. LC – A fiber optic connector, not for antennas.

D. MPO – Used for multi-fiber optic cables, not RF antennas.

A computer network diagram with many boxes and text AI-generated content may be incorrect.

For a web server that requires all connections to be encrypted, port 80 (HTTP) should be disabled. Port 80 is used for unencrypted web traffic, whereas port 443 is used for HTTPS, which provides encrypted communication.

Port 80 (HTTP): This port is used for unsecured web traffic. Disabling this port ensures that all web traffic must use HTTPS, which encrypts the data in transit.

Port 443 (HTTPS): This port is used for secure web traffic via SSL/TLS encryption. Keeping this port open ensures that secure connections can be made to the web server.

Other Ports:

Port 22: Used for SSH, providing secure remote access and file transfers.

Port 587: Used for secure email submission (SMTP) with encryption.

Network References:

CompTIA Network+ N10-007 Official Certification Guide: Discusses the roles and security implications of various ports and protocols.

Cisco Networking Academy: Provides training on secure web server configuration and port management.

Network+ Certification All-in-One Exam Guide: Covers port security and best practices for securing web servers.

Using a /30 subnet mask is the most efficient way to conserve IP space for a point-to-point connection between two routers. A /30 subnet provides four IP addresses, two of which can be assigned to the router interfaces, one for the network address, and one for the broadcast address. This makes it ideal for point-to-point links where only two usable IP addresses are needed.References: CompTIA Network+ study materials and subnetting principles.

Definition of Fiber Connector Types:

LC (Lucent Connector): A small form-factor fiber optic connector with a push-pull latching mechanism, commonly used for high-density applications.

SC (Subscriber Connector or Standard Connector): A larger form-factor connector with a push-pull latching mechanism, often used in datacom and telecom applications.

ST (Straight Tip): A bayonet-style connector, typically used in multimode fiber optic networks.

MPO (Multi-fiber Push On): A connector designed to support multiple fibers (typically 12 or 24 fibers), used in high-density cabling environments.

Common Usage:

LC Connectors: Due to their small size, LC connectors are widely used in network interface cards (NICs) and high-density environments such as data centers. They allow for more connections in a smaller space compared to SC and ST connectors.

SC and ST Connectors: These are larger and more commonly used in patch panels and older fiber installations but are less suitable for high-density applications.

MPO Connectors: Primarily used for trunk cables in data centers and high-density applications but not typically on individual network interface cards.

Selection Criteria:

The small form-factor and high-density capabilities of LC connectors make them the preferred choice for network interface cards, where space and connection density are critical considerations.

•The total number of devices = (150 + 10) users × 2 IPs per user = 320 devices

•Class C (D) supports a maximum of 254 hosts (2^8 - 2), which is too small.

•Class B (B) supports 65,534 hosts (2^16 - 2), making it the best choice.

•Why not the other options?

•Class A (C): Supports millions of addresses, which is overkill for 320 devices.

•Class D (A): Used for multicast, not for device addressing.

Port 22 is used for Secure Shell (SSH), which enables encrypted remote login and command execution on network devices.

Port 23 = Telnet (unencrypted)

Port 80 = HTTP

Port 123 = NTP

From Andrew Ramdayal’s guide:

“SSH uses port 22 to provide secure command-line access to devices such as switches and routers. Unlike Telnet (port 23), SSH encrypts session traffic, making it the preferred method for remote administration.”

A honeynet is a network of honeypots designed to attract and study attackers. Honeypots are decoy systems set up to lure cyber attackers and analyze their activities. A honeynet, being a collection of these systems, provides a broader view of attack methods and patterns, helping organizations improve their security measures. References: CompTIA Network+ Exam Objectives and official study guides.

A split-tunnel VPN allows certain traffic (e.g., cloud-based services) to bypass the VPN and go directly to the Internet. This reduces the amount of traffic that needs to traverse the company's VPN and Internet connection, conserving bandwidth and reducing costs. It also means that not all traffic is subject to the same level of inspection or filtering, which can improve performance for cloud-based services.References: CompTIA Network+ study materials.

Packet loss occurs when network packets fail to reach their destination, leading to disruptions in connectivity and performance issues. In this scenario:

Users report connectivity issues and lag during video meetings.

The administrator detects increased retransmissions in tcpdump, which is a strong indicator of lost packets that must be resent.

Video meetings are particularly sensitive to packet loss, leading to buffering, frozen screens, and dropped calls.

Latency (Option A) refers to delayed data transmission but does not necessarily cause retransmissions.

Bottlenecking (Option C) happens when a network component (e.g., router, switch) cannot handle the traffic load, but packet retransmissions are more directly related to packet loss.

Jitter (Option D) affects the consistency of packet arrival times, but the symptoms described here are more aligned with packet loss rather than timing variations.

? Reference: CompTIA Network+ (N10-009) Official Study Guide – Section: Troubleshooting Connectivity Issues

A Virtual Private Network (VPN) creates an encrypted connection between a remote user and an internal network, ensuring secure access to internal applications.

VPNs use encryption protocols like IPSec and SSL/TLS to protect data during transmission.

They are widely used for secure remote work, accessing company resources, and bypassing geographic restrictions.

Option B (CDN - Content Delivery Network): Used for speeding up website content delivery, not for remote access security.

Option C (SAN - Storage Area Network): Used for high-speed storage, unrelated to remote access.

Option D (IDS - Intrusion Detection System): Monitors for malicious activities but does not provide secure access to applications.

? Reference: CompTIA Network+ (N10-009) Official Study Guide – Section: Secure Remote Access Technologies

The CompTIA Troubleshooting Methodology states that after testing the theory, the next step is to establish a plan of action to resolve the issue.

Troubleshooting Steps:

Identify the problem.

Establish a theory of probable cause.

Test the theory to determine the cause.

Establish a plan of action and implement the solution. ✅ (Correct step)

Verify full system functionality.

Document findings, actions, and outcomes.

Breakdown of Options:

A. Verify full system functionality – Happens after implementing the solution.

B. Document the findings and outcomes – Final step, happens after resolving the issue.

C. Establish a plan of action – ✅ Correct answer. Comes immediately after confirming the cause.

D. Identify the problem – First step, already completed.

Full duplex mode allows devices to send and receive data simultaneously, improving network performance and reducing congestion, which is critical for VoIP and video conferencing.

Breakdown of Options:

A. A VLAN with 100Mbps speed limits – VLANs segment traffic but limiting speeds to 100Mbps would worsen video performance.

B. An IP helper to direct VoIP traffic – IP helper is used for DHCP relay, not for VoIP optimization.

C. A smaller subnet mask – A smaller subnet reduces IP address availability but does not improve network performance.

D. Full duplex on all user ports – Correct answer. Full duplex eliminates collisions, allowing better VoIP and video performance.

A cold site is a backup facility that provides infrastructure (such as power, cooling, and space) but does not have active IT resources installed. When a disaster occurs, IT teams must bring in and configure all necessary hardware and software before services can resume. This process can take weeks or longer—which matches the scenario described.

•Why not the other options?

•Hot site (A) – A hot site is a fully operational backup facility with up-to-date data and pre-configured hardware, allowing almost instant failover (minutes to hours).

•Warm site (B) – A warm site has pre-installed hardware and some software/configurations, but it requires some setup before becoming fully operational (hours to a few days).

•Active-active approach (D) – This means that multiple sites run simultaneously with load balancing, ensuring no downtime in case of a failure.

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

Multitenancy is a cloud concept where multiple customers share the same physical resources (servers, storage, and networks) but remain logically separated for security and privacy.

A. Elasticity is auto-scaling resources.

B. Hybrid cloud combines private and public resources.

C. Scalability is the ability to grow resources but doesn’t imply multiple customers.

References (CompTIA Network+ N10-009):

Domain: Networking Concepts — Cloud computing models, multitenancy in public cloud.

URL filtering can block access to websites based on their domain or country code TLDs (e.g., .cn, .ru). This is the correct method to block by location identifiers in URLs.

B. Content filtering blocks based on keywords or categories within websites, not country code.

C. DNS poisoning is an attack, not a control mechanism.

D. MAC filtering restricts devices, not websites.

References (CompTIA Network+ N10-009):

Domain: Network Security — Filtering technologies, URL vs content filtering.

The first step of troubleshooting is always to identify the problem, which includes verifying the symptoms (incorrect time), asking the user clarifying questions, and checking system logs. Only after confirming the problem can the administrator proceed to form a theory and plan.

A. Plan of action is later.

B. Implement solution comes after testing a theory.

D. Test the theory requires a defined problem first.

References (CompTIA Network+ N10-009):

Domain: Network Troubleshooting — Troubleshooting methodology (Identify → Theory → Test → Plan → Implement → Verify → Document).

When configuring a firewall, the first step is identifying which ports, protocols, and services are required for normal business operations. This ensures only legitimate traffic is allowed. After establishing the required rules, a default deny rule is added for security.

B. Deny all rule is important, but it should come after defining required rules.

C. VPN access is a service to configure, but only after determining baseline needs.

D. Outbound traffic policies are part of refinement, not the first consideration.

References (CompTIA Network+ N10-009):

Domain: Network Security — Firewall configuration, rule order, least privilege.

A load balancer is designed to distribute user requests across multiple servers to ensure high availability and performance.

Breakdown of Options:

A. Router – Directs traffic between networks, not between web servers.

B. Switch – Works at Layer 2, does not distribute web traffic.

C. Firewall – Secures network traffic, but does not distribute load.

D. Load balancer – ✅ Correct answer. Optimizes web traffic distribution across multiple servers.

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.

NAT (Network Address Translation) helps hide internal IP addresses from external networks, adding a layer of security by preventing direct access to internal systems from the outside.

A cable tester is a tool that can help identify issues with the physical cabling, such as breaks or improper terminations, which may prevent the access point from reaching the internet.

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When multiple redundant links exist between switches, Spanning Tree Protocol (STP) is required to prevent switching loops. STP blocks redundant paths but can allow aggregation if configured with protocols like LACP.

B. SVIs provide Layer 3 interfaces, not loop prevention.

C. Native VLAN defines the untagged VLAN but does not manage loops.

D. FHRP (VRRP, HSRP, GLBP) provides gateway redundancy, not switch uplink management.

References (CompTIA Network+ N10-009):

Domain: Network Infrastructure — STP, redundancy, loop prevention.

802.1Q tagging, also known as VLAN tagging, is used to identify VLANs on a trunk link between switches. This allows the switches to transfer data for multiple VLANs (or networks) over a single physical connection. This method ensures that traffic from different VLANs is properly separated and managed across the network.References: CompTIA Network+ study materials.

The loopback address 127.0.0.1 is used to test the TCP/IP stack of the local machine. Pinging this address confirms whether the local system's networking stack is functioning correctly.

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VLAN hopping occurs when an attacker tricks a switch into believing the host is another switch by generating tagged frames or exploiting trunk negotiation (DTP). This allows the attacker to access traffic from multiple VLANs, potentially stealing sensitive data.

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

C. DNS poisoning corrupts name resolution, not VLAN access.

D. ARP spoofing is a Layer 2 on-path attack, not masquerading as a switch.

References (CompTIA Network+ N10-009):

Domain: Network Security — VLAN hopping attacks, switch spoofing techniques.

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

APIs (Application Programming Interfaces) allow automation tools and scripts to push configurations to network devices programmatically. Modern network automation platforms rely on APIs to ensure consistency and scalability.

A. RDP is remote desktop for Windows systems, not automation.

B. Telnet is insecure and manual.

C. GUI requires manual configuration, not automation.

References (CompTIA Network+ N10-009):

Domain: Network Operations — Automation, orchestration, APIs in network management.

The correct answer is public cloud. In public cloud models, a provider (such as AWS, Azure, or Google Cloud) hosts infrastructure and services that are shared across multiple customers, known as multitenancy. Each tenant is logically isolated, but physical infrastructure is shared, allowing providers to achieve economies of scale.

A. Private cloud is dedicated to one organization, not multitenant.

B. Community cloud is shared among organizations with common interests, but it’s less common than public multitenancy.

D. Hybrid cloud combines private and public but does not define tenancy alone.

Public cloud services are the most cost-effective and scalable because they spread costs across many customers, but they require strong security and isolation to protect tenants.

References (CompTIA Network+ N10-009):

Domain: Networking Concepts — Cloud models, multitenancy, public vs private.

To provide a complete solution for configuring the access layer switches, let's proceed with the following steps:

Identify the correct VLANs for each device and port.

Enable necessary ports and disable unused ports.

Configure fault-tolerant connections between the switches.

Port 1 Configuration (Uplink to Core Switch)

Status: Enabled

LACP: Enabled

Speed: 1000

Duplex: Full

VLAN Configuration: Tagged for VLAN60, VLAN90, VLAN120, VLAN150, VLAN220

Port 2 Configuration (Uplink to Core Switch)

Status: Enabled

LACP: Enabled

Speed: 1000

Duplex: Full

VLAN Configuration: Tagged for VLAN60, VLAN90, VLAN120, VLAN150, VLAN220

Port 3 Configuration (Server Connection)

Status: Enabled

LACP: Disabled

Speed: 1000

Duplex: Full

VLAN Configuration: Untagged for VLAN90 (Servers)

Port 4 Configuration (Server Connection)

Status: Enabled

LACP: Disabled

Speed: 1000

Duplex: Full

VLAN Configuration: Untagged for VLAN90 (Servers)

Port 5 Configuration (Wired Users and WLAN)

Status: Enabled

LACP: Enabled

Speed: 1000

Duplex: Full

VLAN Configuration: Tagged for VLAN60, VLAN120, VLAN150

Port 6 Configuration (Wired Users and WLAN)

Status: Enabled

LACP: Enabled

Speed: 1000

Duplex: Full

VLAN Configuration: Tagged for VLAN60, VLAN120, VLAN150

Port 7 Configuration (Voice and Wired Users)

Status: Enabled

LACP: Enabled

Speed: 1000

Duplex: Full

VLAN Configuration: Tagged for VLAN60, VLAN90, VLAN120, VLAN220

Port 8 Configuration (Voice, Printers, and Wired Users)

Status: Enabled

LACP: Enabled

Speed: 1000

Duplex: Full

VLAN Configuration: Tagged for VLAN60, VLAN90, VLAN120, VLAN220

Port 1 Configuration (Unused)

Status: Disabled

LACP: Disabled

Port 2 Configuration (Unused)

Status: Disabled

LACP: Disabled

Port 3 Configuration (Connection to Device)

Status: Enabled

LACP: Disabled

Speed: 1000

Duplex: Full

VLAN Configuration: Untagged for VLAN1 (Default)

Port 4 Configuration (Connection to Device)

Status: Enabled

LACP: Disabled

Speed: 1000

Duplex: Full

VLAN Configuration: Untagged for VLAN1 (Default)

Port 5 Configuration (Connection to Device)

Status: Enabled

LACP: Disabled

Speed: 1000

Duplex: Full

VLAN Configuration: Untagged for VLAN1 (Default)

Port 6 Configuration (Connection to Device)

Status: Enabled

LACP: Disabled

Speed: 1000

Duplex: Full

VLAN Configuration: Untagged for VLAN1 (Default)

Port 7 Configuration (Connection to Device)

Status: Enabled

LACP: Disabled

Speed: 1000

Duplex: Full

VLAN Configuration: Untagged for VLAN1 (Default)

Ports 1 and 2 on Switch 1 are configured as trunk ports with VLAN tagging enabled for all necessary VLANs.

Ports 3 and 4 on Switch 1 are configured for server connections with VLAN 90 untagged.

Ports 5, 6, 7, and 8 on Switch 1 are configured for devices needing access to multiple VLANs.

Unused ports on Switch 3 are disabled.

Ports 3, 4, 5, 6, and 7 on Switch 3 are enabled for default VLAN1.

Core Switch Ports should be configured as needed for uplinks to Switch 1.

Ensure LACP is enabled for redundancy on trunk ports between switches.

By following these configurations, each device will access only its correctly associated network, unused switch ports will be disabled, and fault-tolerant connections will be established between the switches.

Introduction to Subinterfaces:

Subinterfaces are logical interfaces created on a single physical interface. They are used to enable a router to support multiple networks on a single physical interface.

Use Case for Subinterfaces:

Subinterfaces are commonly used in scenarios where VLANs are implemented. A router with a single physical LAN port can be configured with multiple subinterfaces, each associated with a different VLAN.

This setup allows the router to route traffic between different VLANs.

Example Configuration:

Consider a router with a single physical interface GigabitEthernet0/0 and two VLANs, 10 and 20.

interface GigabitEthernet0/0.10

encapsulation dot1Q 10

ip address 192.168.10.1 255.255.255.0

!

interface GigabitEthernet0/0.20

encapsulation dot1Q 20

ip address 192.168.20.1 255.255.255.0

The encapsulation dot1Q command specifies the VLAN ID.

Explanation of the Options:

A. A router with only one available LAN port: This is correct. Subinterfaces allow a single physical interface to manage multiple networks, making it essential for routers with limited physical interfaces.

B. A firewall performing deep packet inspection: Firewalls can use subinterfaces, but it is not a requirement for deep packet inspection.

C. A hub utilizing jumbo frames: Hubs do not use subinterfaces as they operate at Layer 1 and do not manage IP addressing.

D. A switch using Spanning Tree Protocol: STP is a protocol for preventing loops in a network and does not require subinterfaces.

Conclusion:

Subinterfaces provide a practical solution for routing between multiple VLANs on a router with limited physical interfaces. They allow network administrators to optimize the use of available hardware resources efficiently.

NTP (Network Time Protocol) synchronizes clocks across network devices, ensuring accurate timestamps in logs. This is critical for correlating events across different systems during investigations.

A. Syslog collects logs but relies on accurate timestamps already present.

B. SMTP is an email protocol, unrelated to time synchronization.

C. SNMP is for monitoring and management, not time.

References (CompTIA Network+ N10-009):

Domain: Network Operations — Time synchronization (NTP), log correlation, security operations.

BNC (Bayonet Neill–Concelman) connectors are commonly used with coaxial cables in RF and wireless applications, including some older Wi-Fi antennas and specialized networking equipment. The document says:

“BNC (Bayonet Neill–Concelman) connectors are typically used with coaxial cables, especially in radio frequency (RF) and some Wi-Fi antenna applications, providing a secure and quick connect/disconnect.”

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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VLAN hopping allows an attacker to send traffic into another VLAN without authorization, often by impersonating a switch and negotiating a trunk link. This lets the attacker traverse into normally inaccessible VLANs.

A. MAC flooding disrupts switch operations but does not cross VLANs.

B. DNS poisoning corrupts name resolution.

D. ARP spoofing reroutes local traffic but doesn’t grant VLAN traversal.

References (CompTIA Network+ N10-009):

Domain: Network Security — VLAN attacks, unauthorized lateral movement.

Understanding MTBF:

Mean Time Between Failures (MTBF): A reliability metric that estimates the average time between successive failures of a device or system.

Calculation and Importance:

Calculation: MTBF is calculated as the total operational time divided by the number of failures during that period.

Usage: Used by manufacturers and engineers to predict the lifespan and reliability of a device, helping in maintenance planning and lifecycle management.

Comparison with Other Metrics:

RTO (Recovery Time Objective): The maximum acceptable time to restore a system after a failure.

RPO (Recovery Point Objective): The maximum acceptable amount of data loss measured in time.

MTTR (Mean Time to Repair): The average time required to repair a device or system and return it to operational status.

Application:

MTBF is crucial for planning maintenance schedules, spare parts inventory, and improving the overall reliability of systems.

This is a classic example of social engineering, where an attacker manipulates individuals into giving up confidential information, such as credentials, by pretending to be someone trustworthy (like help desk staff).

B. Tailgating involves physical access without authentication.

C. Shoulder surfing is spying over someone's shoulder to steal info.

D. Smishing is phishing via SMS.

E. Evil twin involves a rogue Wi-Fi access point impersonating a legitimate one.

???? Reference:

CompTIA Network+ N10-009 Official Objectives: 4.2 – Identify common security threats and vulnerabilities.

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When traffic moves laterally between VMs within the same network or subnet, it is known as east-west traffic. This contrasts with north-south traffic, which refers to communication between internal and external networks.

Breakdown of Options:

A. East-west – Correct answer. This refers to traffic between internal servers or VMs, which is a common security concern.

B. Point-to-point – Point-to-point describes a direct connection between two devices, but does not specifically define lateral movement.

C. Horizontal-scaling – This refers to adding more instances or nodes in cloud computing, unrelated to traffic flow.

D. Hub-and-spoke – This network topology describes a centralized design, not lateral traffic.

802.11ax, also known as Wi-Fi 6, is designed for high-density environments and improves device saturation and coverage compared to previous standards.

802.11ac: While it offers high throughput, it is not optimized for high-density environments as effectively as 802.11ax.

802.11ax (Wi-Fi 6): Introduces features like OFDMA, MU-MIMO, and BSS Coloring, which enhance performance in crowded environments, reduce latency, and increase the number of devices that can be connected simultaneously.

802.11g and 802.11n: Older standards that do not offer the same level of efficiency or support for high device density as 802.11ax.

Network References:

CompTIA Network+ N10-007 Official Certification Guide: Covers the 802.11 standards and their capabilities.

Cisco Networking Academy: Provides training on Wi-Fi technologies and best practices for high-density deployments.

Network+ Certification All-in-One Exam Guide: Discusses the various 802.11 standards and their applications in different environments.

The correct solution is a Data Center Interconnect (DCI). DCIs extend Layer 2 networks across geographically dispersed data centers, enabling seamless replication of services such as SAN storage, backup synchronization, or VM migrations. This ensures workloads and data can move between sites while maintaining the same VLANs and addressing.

A. Security Service Edge (SSE) provides cloud-delivered security functions like secure web gateways and CASB, not Layer 2 extension.

C. Infrastructure as code (IaC) automates deployment and management of network infrastructure but is unrelated to extending Layer 2 domains.

D. Zero Trust architecture is a security framework ensuring strict access control but doesn’t address network connectivity between sites.

In scenarios where backups need replication between sites, Layer 2 extension is often required so systems can communicate as if they are in the same broadcast domain. DCI is specifically designed to provide this functionality reliably and securely.

References (CompTIA Network+ N10-009):

Domain: Network Infrastructure — WAN technologies, data center interconnect, backup replication.

APIPA (Automatic Private IP Addressing) assigns an IP address in the range 169.254.x.x when a DHCP server cannot be contacted, and it sets the default gateway to 0.0.0.0 because APIPA is designed only for local communication within the same subnet. The document states:

“APIPA allows for automatic, ad hoc network communication within a single subnet when a DHCP server is not available. In this state, the default gateway is typically set to 0.0.0.0 because APIPA does not provide routing to other networks.”

Port Address Translation (PAT) allows multiple internal devices to share a single public IP address by assigning each device a unique port number. This is the most common method used in environments where many systems need internet access but there are limited public IP addresses.

Single Sign-On (SSO) enables a user to access multiple resources or applications with one set of credentials, improving usability and security. The document confirms:

“Single Sign-On (SSO) allows a user to authenticate once and gain access to multiple resources or applications without needing to log in again for each. It streamlines the login process and improves security by reducing the number of passwords that need to be managed.”

Port 443 is used by HTTPS (Hypertext Transfer Protocol Secure), a secure version of HTTP that uses SSL/TLS to encrypt the communication between a client and server. This ensures confidentiality and integrity of data in transit. The document states:

“Port 443 is the default port for HTTPS, which secures HTTP traffic using SSL/TLS, providing encryption and secure identification of web servers.”

The correct metric is RTO (Recovery Time Objective). RTO defines the maximum acceptable time to restore services after a disruption, ensuring business continuity. For example, if the RTO is 4 hours, systems must be back online within that timeframe after an outage.

B. MTBF (Mean Time Between Failures) measures reliability by calculating the average time between hardware failures.

C. RPO (Recovery Point Objective) defines how much data loss (in terms of time, such as last backup point) is acceptable.

D. MTTR (Mean Time to Repair) measures the average time taken to fix a failure but is not a predefined business requirement like RTO.

Organizations define RTOs during disaster recovery planning to align IT recovery capabilities with business needs.

References (CompTIA Network+ N10-009):

Domain: Networking Concepts — Business continuity metrics (RTO, RPO, MTBF, MTTR).

When a host fails to obtain an IP address from a DHCP server, it assigns itself an APIPA (Automatic Private IP Addressing) address in the 169.254.x.x range, commonly described as a “self-assigned IP.” This prevents communication outside the local link, including reaching the default gateway.

B. RFC1918 addresses are private ranges (10.x.x.x, 172.16–31.x.x, 192.168.x.x), but these are not self-assigned.

C. If the TCP/IP stack were disabled, the host wouldn’t have any IP at all.

D. If a static IP were assigned, it would show a configured value, not self-assigned.

References (CompTIA Network+ N10-009):

Domain: Network Troubleshooting — IP addressing issues, DHCP failures, APIPA behavior.

The ST (Straight Tip) fiber connector is round with a bayonet twist-lock mechanism. It is older but still used in some fiber installations.

B. BNC is a coaxial connector.

C. SC (Subscriber Connector) is a square push-pull fiber connector.

D. LC (Lucent Connector) is a small form-factor fiber connector.

References (CompTIA Network+ N10-009):

Domain: Networking Concepts — Fiber connectors (ST, SC, LC).

To increase overall security after a recent breach, implementing least privilege network access and central policy management are effective strategies.

Least Privilege Network Access: This principle ensures that users and devices are granted only the access necessary to perform their functions, minimizing the potential for unauthorized access or breaches. By limiting permissions, the risk of an attacker gaining access to critical parts of the network is reduced.

Central Policy Management: Centralized management of security policies allows for consistent and streamlined implementation of security measures across the entire network. This helps in quickly responding to security incidents, ensuring compliance with security protocols, and reducing the chances of misconfigurations.

Network References:

CompTIA Network+ N10-007 Official Certification Guide: Discusses network security principles, including least privilege and policy management.

Cisco Networking Academy: Provides training on implementing security policies and access controls.

Network+ Certification All-in-One Exam Guide: Covers strategies for enhancing network security and managing policies effectively.

Link Layer Discovery Protocol (LLDP) is a network protocol used for discovering devices and their capabilities on a local area network, primarily at the data link layer (Layer 2). It helps in identifying the connected switch and the specific port to which a device is connected. When troubleshooting a VoIP handset connection, the technician can use LLDP to determine the exact switch and port where the handset is connected. This protocol is widely used in network management to facilitate the discovery of network topology and simplify troubleshooting.

Other options such as IKE (Internet Key Exchange), VLAN (Virtual LAN), and netstat (network statistics) are not suitable for identifying the switch and port information. IKE is used in setting up secure IPsec connections, VLAN is used for segmenting networks, and netstat provides information about active connections and listening ports on a host but not for discovering switch port details.

Disabling unused ports prevents unauthorized access and reduces the attack surface by ensuring that no inactive or unmonitored entry points are available for exploitation. Changing default passwords is critical for security because default credentials are widely known and can easily be exploited by attackers. These techniques are fundamental steps in hardening devices against unauthorized access and ensuring network security. References: CompTIA Network+ Exam Objectives and official study guides.

Understanding Spanning Tree Protocol (STP):

STP is used to prevent network loops in Ethernet networks by creating a spanning tree that selectively blocks some redundant paths.

Default Priority Value:

Bridge Priority: STP uses bridge priority to determine which switch becomes the root bridge. The default bridge priority value for most switches is 32768.

Priority Range: The bridge priority can be set in increments of 4096, ranging from 0 to 61440.

Configuration and Verification:

When deploying a new switch, the network administrator can verify the bridge priority using commands such as show spanning-tree to ensure it is set to the default value of 32768.

Comparison with Other Values:

4096 and 8192: Lower than the default priority, indicating these would be manually configured for higher preference.

36684: A non-standard value, likely a result of specific configuration changes.

Understanding Subnetting:

Original Network: 192.168.1.0/24 has a subnet mask of 255.255.255.0, which allows for 256 IP addresses (including network and broadcast addresses).

Objective: Divide this network into two equal subnets.

Calculating Subnet Mask:

New Subnet Mask: To divide 192.168.1.0/24 into two equal halves, we need to borrow one bit from the host portion of the address, changing the subnet mask to 255.255.255.128 (/25).

Subnet Breakdown:

First Subnet: 192.168.1.0/25 (192.168.1.0 - 192.168.1.127)

Second Subnet: 192.168.1.128/25 (192.168.1.128 - 192.168.1.255)

Verification:

Each subnet now has 128 IP addresses (126 usable IP addresses, excluding the network and broadcast addresses).

Comparison with Other Options:

255.255.0.0 (/16): Provides a much larger network, not dividing the original /24 network.

255.255.254.0 (/23): Also creates a larger subnet, encompassing more than the original /24 network.

255.255.255.0 (/24): Maintains the original subnet size, not dividing it.

MIBs (Management Information Bases) define the variables and objects that SNMP can query on a device. If the monitoring server authenticates but cannot interpret the data, it likely lacks the correct MIB for that vendor or model. Importing the proper MIB allows the monitoring server to correctly display device status and metrics.

A. Using a public community string is insecure and not related to missing MIBs.

C. Switchport analyzer (SPAN) captures traffic for packet analysis, not SNMP monitoring.

D. SNMPv3 privacy adds encryption but doesn’t fix missing MIB interpretation.

References (CompTIA Network+ N10-009):

Domain: Network Operations — SNMP, MIBs, network monitoring systems.

The correct answer is OSPF (Open Shortest Path First). OSPF is a link-state routing protocol known for its fast convergence and use of the Dijkstra algorithm to calculate the shortest loop-free path. It efficiently scales to large enterprise networks and avoids routing loops by maintaining a complete topology map.

A. BGP is primarily an external routing protocol used between ISPs, not internal.

B. STP is not a routing protocol; it prevents loops at Layer 2.

D. RIP is an older distance-vector protocol with slower convergence and a maximum hop limit of 15.

OSPF’s design makes it the preferred internal gateway protocol (IGP) for medium-to-large organizations requiring speed and loop-free reliability.

References (CompTIA Network+ N10-009):

Domain: Networking Concepts — IGPs, OSPF, routing protocols.

IPsec (Internet Protocol Security) is the most secure way to provide site-to-site connectivity. It provides robust security services, such as data integrity, authentication, and encryption, ensuringthat data sent across the network is protected from interception and tampering. Unlike other options, IPsec operates at the network layer and can secure all traffic that crosses the IP network, making it the most comprehensive and secure choice for site-to-site VPNs.References: CompTIA Network+ study materials and NIST Special Publication 800-77.

A warm site typically has a full infrastructure ready, but it lacks the most up-to-date data or is not immediately operational. It requires some configuration or data restoration to become fully functional.

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A jump box is a hardened, isolated system that provides secure access to critical infrastructure devices like routers and firewalls.

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

802.1X provides port-based Network Access Control (NAC), requiring authentication (often through RADIUS) before granting access. This is the standard for enterprise authentication on both wired and wireless networks.

A. 802.1Q defines VLAN trunking.

C. 802.3bt defines higher-power PoE.

D. 802.11h deals with spectrum management in wireless.

References (CompTIA Network+ N10-009):

Domain: Network Security — NAC, 802.1X authentication.

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

For a log collector server, the primary needed service is Syslog, which typically uses UDP port 514. Other ports may be open for management (e.g., 22 for SSH) or SNMP traps (162) if integrated. However, port 80 (HTTP) should not be open unless required, as it increases attack surface and does not directly serve the log collection purpose. Disabling it hardens the server.

A. 22 (SSH) is needed for secure management.

C. 162 (SNMP trap) may be required for monitoring/log correlation.

D. 514 (Syslog) is essential for log collection.

References (CompTIA Network+ N10-009):

Domain: Network Security — Hardening servers, disabling unnecessary services and ports.

MFA (Multi-Factor Authentication) requires factors from different categories:

Something you know → Password, PIN

Something you have → Smart card, hardware (hard) token

Something you are → Biometric

The correct second factor is a hard token.

A. PIN = something you know (same factor as password).

B. Favorite color = knowledge-based, same factor as password.

D. Mother’s maiden name = weak knowledge-based, same factor as password.

References (CompTIA Network+ N10-009):

Domain: Network Security — Authentication methods, MFA categories.

EIGRP (Enhanced Interior Gateway Routing Protocol) is a Cisco proprietary advanced distance-vector routing protocol. While it operates within an Autonomous System (AS), it requires the AS number to be configured for routers to recognize each other as EIGRP neighbors.

OSPF (Open Shortest Path First) uses areas and routers must be in the same area to form adjacencies, but it doesn't require AS numbers in the same way.

FHRP (First Hop Redundancy Protocol) is not a routing protocol but a group of protocols (e.g., HSRP, VRRP) to ensure high availability at the default gateway level.

RIP (Routing Information Protocol) does not use autonomous system numbers.

???? Reference:

CompTIA Network+ N10-009 Official Objectives: 3.1 – Compare and contrast various routing technologies.

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The option that most directly secures sensitive information on the network is data-in-transit encryption. This ensures that data packets are unreadable to attackers who intercept them while moving across the network. Protocols such as TLS, HTTPS, IPsec, and SSH protect confidentiality and integrity of sensitive information.

B. Principle of least privilege (PoLP) secures access control but does not directly protect data in motion.

C. Role-based access control (RBAC) enforces permissions but again does not secure the data while transmitted.

D. Multifactor authentication (MFA) strengthens identity verification but does not directly protect the data itself once transmitted.

Thus, while all options contribute to overall security, encryption of data-in-transit most directly addresses protection of sensitive information on the network.

References (CompTIA Network+ N10-009):

Domain: Network Security — Encryption methods, confidentiality, data-in-transit protection.

•Cable termination issues (e.g., improper crimping, loose connectors) can cause connectivity failures.

•Power budget (A) applies to PoE devices, not general cabling issues.

•Device requirements (B) relate to software/hardware compatibility, not wiring faults.

•Port status (C) would help if the issue was switch-related, but since moving devices didn’t help, it’s likely a cabling issue.

????Reference: CompTIA Network+ N10-009 Official Documentation – Cabling & Physical Layer Troubleshooting.

To support VoIP on a network with limited switchports, the engineer should configure voice VLANs and enable 802.1Q tagging. Voice VLANs allow VoIP traffic to be prioritized and isolated from data traffic even when sharing the same physical port. 802.1Q is used for VLAN tagging, enabling multiple VLANs over a single physical link.

From Andrew Ramdayal’s guide:

“Voice VLANs allow IP phones and computers to share the same physical switch port while keeping their traffic separate. 802.1Q is used to tag VLAN traffic so that it can be appropriately routed and prioritized.”

A system has reachedend-of-supportwhen thevendor no longer provides patches, updates, or bug fixes. This significantly increases the risk of security vulnerabilities and is a major operational concern.

The customer can access local resources (a database server), which means local networking is working. However, the inability to reach the internet suggests an issue with the default gateway. If the default gateway is unreachable, packets will not be routed outside the local network.

Breakdown of Options:

A. Incorrect DNS – DNS issues would cause problems resolving domain names, but the user should still be able to access external resources via IP addresses.

B. Unreachable gateway – ✅ Correct answer. If the default gateway is incorrect or unreachable, the device cannot route traffic to the internet.

C. Failed root bridge – STP (Spanning Tree Protocol) failures cause switching issues, but the user can still access local devices, meaning STP is not the problem.

D. Poor upstream routing – Would affect the entire network, not just one user.

The most likely reason an insurance brokerage would enforce VPN usage is to encrypt sensitive data in transit. VPNs (Virtual Private Networks) create a secure tunnel between the user's device and the corporate network, ensuring that data is encrypted and protected from interception.

Encryption: VPNs encrypt data, preventing unauthorized access and ensuring data privacy during transmission over public or unsecured networks.

Data Protection: Essential for industries handling sensitive information, such as insurance brokerages, to protect customer data and comply with regulatory requirements.

Security: Enhances overall network security by providing secure remote access for employees.

Network References:

CompTIA Network+ N10-007 Official Certification Guide: Discusses the role of VPNs in securing data in transit.

Cisco Networking Academy: Provides training on VPN technologies and their importance in data security.

Network+ Certification All-in-One Exam Guide: Explains VPN usage and its benefits in protecting sensitive information.

Voice VLANs rely on 802.1Q tagging to separate voice traffic from data traffic on the same physical link. This separation allows QoS policies to prioritize VoIP, reducing jitter and packet loss.

B. Jumbo frames improve throughput for large data transfers, not voice.

C. Native VLAN is the untagged VLAN, not specifically for voice.

D. Link aggregation bundles links for bandwidth/redundancy, not QoS.

References (CompTIA Network+ N10-009):

Domain: Network Infrastructure — VLANs, voice VLANs, 802.1Q tagging, QoS.

Introduction to Administrative Distance

Administrative distance (AD) is a value used by routers to rank routes from different routing protocols. AD represents the trustworthiness of the source of the route. Lower AD values are more preferred. If a router has multiple routes to a destination from different sources, it will choose the route with the lowest AD.

Static Routes and Backup Routes

When a dynamic routing protocol is not used, static routes can be employed. Static routes are manually configured routes. To ensure a backup route, multiple static routes to the same destination can be configured with different AD values.

Configuring Static Routes with Administrative Distance

The primary route is configured with a lower AD value, making it the preferred route. The backup route is configured with a higher AD value. In the event of the primary route failure, the router will then use the backup route.

Example Configuration:

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ip route 192.168.1.0 255.255.255.0 10.0.0.1 1

ip route 192.168.1.0 255.255.255.0 10.0.0.2 10

In the above example, 192.168.1.0/24 is the destination network.

10.0.0.1 is the next-hop IP address for the primary route with an AD of 1.

10.0.0.2 is the next-hop IP address for the backup route with an AD of 10.

Verification:

After configuration, use the show ip route command to verify that the primary route is in use and the backup route is listed as a candidate for use if the primary route fails.

Network Functions Virtualization (NFV): NFV is a technology that virtualizes network services like routing, firewalls, and load balancers. It allows these services to run on virtual machines rather than requiring dedicated hardware. This is ideal for remote branch locations where deploying physical devices is costly and complex.

VRF (B): Virtual Routing and Forwarding is used for segmenting routing tables but does not virtualize services.

VLAN (C): Virtual Local Area Networks help segregate broadcast domains but are unrelated to virtualizing network functions.

VPC (D): Virtual Private Cloud is used for cloud computing but does not pertain to virtualizing network services.

In a data center that uses hot aisle/cold aisle ventilation, equipment is typically installed so that cool air enters from the cold aisle (front) and hot air is exhausted to the hot aisle (rear). This configuration maximizes cooling efficiency.

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.

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

An ad hoc wireless network allows devices to connect directly to each other without an access point. This is suitable for small, temporary setups like two laptops and a printer.

A. Mesh requires multiple nodes forming a larger distributed network.

B. Infrastructure requires an AP, which is not available here.

D. Point-to-point is typically for long-distance wireless links between two fixed endpoints.

References (CompTIA Network+ N10-009):

Domain: Networking Concepts — Wireless network types: infrastructure, ad hoc, mesh.

A split-tunnel VPN allows some traffic to be routed through the VPN while other traffic goes directly to the internet. This setup offers several advantages, with a primary one being cost-effectiveness due to cloud-based traffic not consuming company bandwidth.

Bandwidth Utilization: Split-tunnel VPNs reduce the amount of traffic passing through the company's network, freeing up bandwidth for other uses.

Performance: By allowing internet-bound traffic to bypass the VPN, it can reduce latency and improve the performance for users accessing cloud services directly.

Cost Savings: Reduced load on the company's VPN infrastructure can lead to lower costs in terms of both hardware and bandwidth.

Network References:

CompTIA Network+ N10-007 Official Certification Guide: Covers VPN types, including split-tunnel configurations and their advantages.

Cisco Networking Academy: Discusses VPN technologies and the benefits of split-tunneling.

Network+ Certification All-in-One Exam Guide: Provides detailed information on VPN setups, including the cost-effectiveness of split-tunnel VPNs.

By allowing cloud-based traffic to flow outside the company’s network, a split-tunnel VPN optimizes resource usage and enhances the overall network performance without incurring extra costs for bandwidth.

A warm site is a compromise between a hot site and a cold site, providing a balance between cost and recovery time. It is partially equipped with the necessary hardware, software, and infrastructure, allowing for a quicker recovery compared to a cold site but at a lower cost than a hot site.

Recovery Time: Warm sites can be operational within hours to a day, making them suitable for non-critical applications that can tolerate short downtimes.

Cost-Effectiveness: Warm sites are more economical than hot sites as they do not require all systems to be fully operational at all times.

Network References:

CompTIA Network+ N10-007 Official Certification Guide: Discusses disaster recovery strategies and the different types of recovery sites.

Cisco Networking Academy: Provides training on disaster recovery planning and site selection.

Network+ Certification All-in-One Exam Guide: Explains the characteristics of hot, warm, and cold sites and their use cases in disaster recovery planning.

Warm sites offer a practical solution for maintaining business continuity for non-critical applications, balancing the need for availability with cost considerations.

Content filtering blocks access to restricted or malicious websites. When a user attempts to visit a site that violates company policies, they are redirected to a restriction page.

This is a common security measure to prevent employees from accessing phishing or malware-infected sites.

Content filters work by scanning URLs, keywords, or categories and blocking inappropriate or harmful content.

Option A (DLP - Data Loss Prevention): Focuses on preventing sensitive data leaks rather than blocking web access.

Option B (Captive portal): Used mainly in public Wi-Fi to authenticate users before granting access, not to restrict sites.

Option D (DNS sinkholing): Redirects malicious domain requests to a safe address but is not responsible for policy-based restrictions on general content.

? Reference: CompTIA Network+ (N10-009) Official Study Guide – Section: Security Solutions

The key difference is that an Intrusion Prevention System (IPS) is installed in line with network traffic, allowing it to actively block threats. In contrast, an Intrusion Detection System (IDS) only monitors and alerts without actively blocking traffic.

Breakdown of Options:

A. An IPS needs to be installed in line with traffic and an IDS does not. ✅ Correct answer. IPS actively prevents threats, while IDS only detects them.

B. An IPS is signature-based and an IDS is not. – False, both can use signature-based detection.

C. An IPS is less susceptible to false positives than an IDS. – False, both can produce false positives, depending on configurations.

D. An IPS requires less administrative overhead than an IDS. – False, IPS requires more administrative effort due to real-time blocking decisions.

When traceroute shows asterisks (timeouts) instead of IP addresses or hostnames, it may indicate that intermediate routers are dropping ICMP packets. However, performing an nslookup will reveal the IP address associated with the domain name, confirming that DNS resolution is correct and helping identify the path to the target server. The document states:

“nslookup is used to query DNS servers to retrieve IP address information associated with a domain name, which helps confirm DNS resolution is working correctly even when traceroute results show timeouts.”

The issue is that more students have arrived on campus, meaning the available IP addresses are exhausted. To fix this, the administrator should increase the DHCP scope size to allow more devices to obtain IP addresses.

Breakdown of Options:

A. Enable IP helper – IP helper is used to forward DHCP requests across different subnets. However, the problem here is that the DHCP scope is full, not that requests are not reaching the server.

B. Change the subnet mask – The subnet mask determines the number of available hosts, but changing it without increasing the IP pool does not help.

C. Increase the scope size – Correct answer. Expanding the DHCP scope provides more IP addresses for assignment.

D. Add address exclusions – Exclusions reserve IP addresses, which would further reduce available addresses instead of solving the issue.

An access point (AP) provides users with an extended footprint that allows connections from multiple devices within a designated Wireless Local Area Network (WLAN).

Router: Typically used to connect different networks, not specifically for extending wireless coverage.

Switch: Used to connect devices within a wired network, not for providing wireless access.

Access Point (AP): Extends wireless network coverage, allowing multiple wireless devices to connect to the network.

Firewall: Primarily used for network security, controlling incoming and outgoing traffic based on security rules, not for providing wireless connectivity.

Network References:

CompTIA Network+ N10-007 Official Certification Guide: Explains the roles and functions of network appliances, including access points.

Cisco Networking Academy: Provides training on deploying and managing wireless networks with access points.

Network+ Certification All-in-One Exam Guide: Covers network devices and their roles in creating and managing networks.

On the first exhibit, the layout should be as follows

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Exhibit 2 as follows

Access Point Name AP2

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Exhibit 3 as follows

Access Point Name AP3

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When a network interface's indicator lights are not blinking on either the computer or the switch, it suggests a physical layer issue. Here is the detailed reasoning:

Ethernet Properly Connected: The Ethernet cable is correctly connected, eliminating issues related to a loose or faulty cable.

No Indicator Lights: The absence of blinking indicator lights on both the computer and the switch typically points to the port being administratively shut down.

Switch Port Shut Down: In networking, a switch port can be administratively shut down, disabling it from passing any traffic. This state is configured by network administrators and can be verified and changed using the command-line interface (CLI) of the switch.

Command to Check and Enable Port:

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Switch> enable

Switch# configure terminal

Switch(config)# interface [interface id]

Switch(config-if)# no shutdown

The command no shutdown re-enables the interface if it was previously disabled. This will restore the link and the indicator lights should start blinking, showing activity.

Basic Configuration Commands PDF, sections on interface configuration (e.g., shutdown, no shutdown)​​.

At the transport layer, connectionless communication is typically handled using the User Datagram Protocol (UDP), which transmits data in units called datagrams. Unlike TCP, UDP does not establish a connection before sending data and does not guarantee delivery, making datagrams the correct term for the transmission format in this context. References: CompTIA Network+ Exam Objectives and official study guides.

Twinaxial (Direct Attach Copper / DAC) cables can plug directly into QSFP ports without needing separate optical transceivers. They are cost-effective for short-distance, high-speed connections (commonly in data centers).

A. Multimode fiber requires SFP/QSFP transceivers to convert electrical signals to optical.

C. RG11 is coaxial cable for broadband/cable TV, not used in QSFP ports.

D. Category 6 is twisted-pair Ethernet cabling, not directly compatible with QSFP ports.

References (CompTIA Network+ N10-009):

Domain: Network Infrastructure — Cable types, QSFP, DAC (Twinaxial), transceiver requirements.

Introduction to Security Zones:

Security zones are logical segments within a network designed to enforce security policies and control access. They help in segregating and securing different parts of the network.

Types of Security Zones:

Trusted Zone: This is the most secure zone, typically used for internal corporate networks where only trusted users have access.

Extranet: This zone allows controlled access to external partners, vendors, or customers.

VPN (Virtual Private Network): While VPNs are used to create secure connections over the internet, they are not a security zone themselves.

Public Zone: This zone is the least secure and is typically used for public-facing services accessible by anyone.

Trusted Zone Implementation:

The trusted zone is configured to include internal corporate users and resources. Access controls, firewalls, and other security measures ensure that only authorized personnel can access this zone.

Internal network segments, such as the finance department, HR, and other critical functions, are usually placed in the trusted zone.

Example Configuration:

Firewall Rules: Set up rules to allow traffic only from internal IP addresses.

Access Control Lists (ACLs): Implement ACLs on routers and switches to restrict access based on IP addresses and other criteria.

Segmentation: Use VLANs and subnetting to segment and isolate the trusted zone from other zones.

Explanation of the Options:

A. Extranet: Suitable for external partners, not for internal-only access.

B. Trusted: The correct answer, as it provides controlled access to internal corporate users.

C. VPN: A method for secure remote access, not a security zone itself.

D. Public: Suitable for public access, not for internal corporate users.

Conclusion:

Implementing a trusted zone is the best solution for controlling access within a corporate network. It ensures that only trusted internal users can access sensitive resources, enhancing network security.

224.0.0.1 is a multicast address that allows packets to be sent to all hosts within a multicast group. Since video streaming often uses multicast to efficiently distribute data to multiple clients without unnecessary duplication, this is the correct answer.

•Why not the other options?

•127.0.0.1 (A) – This is the loopback address used for internal device testing, not for multicast traffic.

•172.17.1.1 (B) – This is a private unicast address, meaning it can only send packets to one specific host.

•240.0.0.1 (D) – This falls within the reserved experimental IP address range and is not used for multicast.

Definition of ESP (Encapsulating Security Payload):

ESP is a part of the IPsec protocol suite designed to provide confidentiality, integrity, and authenticity of data by encrypting the payload and optional ESP trailer.

Ensuring Confidentiality:

Encryption: ESP encrypts the payload, ensuring that the data remains confidential during transmission. Only authorized parties with the correct decryption keys can access the data.

Modes of Operation: ESP can operate in transport mode (encrypts only the payload) or tunnel mode (encrypts the entire IP packet), both providing strong encryption to secure data between sites.

Comparison with Other Protocols:

GRE (Generic Routing Encapsulation): A tunneling protocol that does not provide encryption or security features.

IKE (Internet Key Exchange): A protocol used to set up a secure, authenticated communications channel, but it does not encrypt the data itself.

AH (Authentication Header): Provides integrity and authentication for IP packets but does not encrypt the payload.

Implementation:

Use ESP as part of an IPsec VPN configuration to encrypt and secure communication between two sites. This involves setting up IPsec policies and ensuring both endpoints are configured to use ESP for data encryption.

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.

When installing equipment in a building, environmental factors are critical to ensure the safety and longevity of the equipment. A fire suppression system is essential to protect the equipment from fire hazards. Humidity control is crucial to prevent moisture-related damage, such ascorrosion and short circuits, which can adversely affect electronic components. Both factors are vital for maintaining an optimal environment for networking equipment.References: CompTIA Network+ study materials.

EIGRP (Enhanced Interior Gateway Routing Protocol) has a default administrative distance (AD) value of 90 for internal routes. The administrative distance is used to rate the trustworthiness of routing information received from different routing protocols. EIGRP, developed by Cisco, has an AD of 90, which is lower than that of RIP (120) and OSPF (110), making it more preferred if multiple protocols provide a route to the same destination.References: CompTIA Network+ study materials.

An IP Helper (IP Helper Address) allows DHCP requests to pass through routers and reach a DHCP server on another network.

DHCP broadcasts are not forwarded across routers by default, so an IP Helper Address is needed to relay the request.

This is crucial for large networks where a single DHCP server serves multiple subnets.

Option B (Reservation): Ensures a specific IP address is assigned to a MAC address but does not relay DHCP across networks.

Option C (Exclusion): Prevents specific IP addresses from being assigned, but does not help with DHCP relay.

Option D (Scope): Defines the range of IP addresses available for DHCP clients but does not assist in cross-network communication.

? Reference: CompTIA Network+ (N10-009) Official Study Guide – Section: DHCP and IP Addressing

The best solution here is band steering. Band steering allows modern wireless access points to automatically direct dual-band capable clients toward the 5 GHz band instead of the crowded 2.4 GHz band. The 5 GHz band has more available non-overlapping channels and can provide faster speeds with less interference, especially in dense environments. Devices that only support 2.4 GHz will remain on that band, while compatible devices enjoy the improved performance of 5 GHz.

A. 802.1X is a port-based network access control method for authentication. While important for security, it does not affect wireless channel utilization or client throughput.

B. MIMO (Multiple Input, Multiple Output) is a technology that improves throughput by using multiple antennas to send/receive simultaneously, but it does not actively steer clients between frequency bands.

C. ESSID (Extended Service Set Identifier) is just the network name for a set of APs in the same WLAN; it has no role in optimizing performance by band.

By implementing band steering, administrators reduce channel overlap on the 2.4 GHz band, improve spectral efficiency, and provide higher performance to capable devices, directly meeting the requirements described in the scenario.

References (CompTIA Network+ N10-009):

Domain: Networking Concepts — Wireless optimization, band steering, dual-band client management.

Multitenancy is a cloud computing architecture where a single instance of software serves multiple customers or tenants. Each tenant's data is isolated and remains invisible to other tenants. Hosting a company application in the cloud to be available for both internal and third-party users fits this concept, as it allows shared resources and infrastructure while maintaining data separation and security. References: CompTIA Network+ Exam Objectives and official study guides.

In a mesh topology, every node is directly connected to every other node. This provides high redundancy and reliability, as there are multiple paths for data to travel between nodes. This topology is often used in networks where high availability is crucial.References: CompTIA Network+ study materials.

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.

SIEM (Security Information and Event Management) systems are used to aggregate and analyze log data from various sources, including firewalls, to detect potential security incidents and assist in regulatory compliance. The document explains:

“SIEM solutions aggregate and analyze log and event data from multiple devices, including firewalls, across different locations. They help in real-time monitoring, incident response, and ensuring compliance with security policies.”

The correct answer is golden configuration. This is a reference standard or baseline that defines the approved settings and rules devices should follow. Any deviation from the golden configuration indicates drift or misconfiguration that must be remediated.

A. Production refers to the live environment but doesn’t define a standard.

B. Backup configurations are stored copies, not the standard rules.

C. Candidate configuration is a proposed change being tested, not the final baseline.

By enforcing golden configurations, administrators ensure compliance, maintain security standards, and improve consistency across the enterprise.

References (CompTIA Network+ N10-009):

Domain: Network Operations — Configuration standards, golden images/configs.

The netstat output shows that multiple ports are open, including Telnet (23), FTP (20), and TFTP (69), which are potential security risks. Disabling unused ports minimizes the attack surface, reducing security vulnerabilities.

Breakdown of Options:

A. Disable the unused ports – Correct answer. Unused ports should be closed to prevent unauthorized access.

B. Enforce access control lists – ACLs help control access but do not disable unnecessary services.

C. Perform content filtering – Content filtering controls web traffic, not port security.

D. Set up a screened subnet – A DMZ (screened subnet) improves security but does not address open ports.

A DDoS (Distributed Denial of Service) attack is often launched from botnets — networks of compromised systems (bots or zombies) under the control of an attacker. These devices flood the target with traffic to disrupt services.

A. Evil twin attack is a wireless spoofing method.

C. XML injection targets web applications.

D. Brute-force attacks repeatedly guess passwords but don't involve a botnet by default.

???? Reference:

CompTIA Network+ N10-009 Official Objectives: 4.2 – Identify common security threats and vulnerabilities.

A toner probe, often referred to as a toner and probe kit, is the easiest and most effective tool for identifying individual cables in a bundle, especially in situations where the patch panel is not labeled. The toner sends an audible tone through the cable, and the probe detects the tone at the other end, allowing the technician to quickly identify the correct cable.

Functionality: The toner generates a tone that travels along the cable. When the probe is placed near the correct cable, it detects the tone and emits a sound.

Ease of Use: Toner probes are straightforward to use, even in environments with many cables, making them ideal for identifying cables in unlabeled patch panels.

Efficiency: This method is much faster and more reliable than manual tracing, especially in complex setups.

Network References:

CompTIA Network+ N10-007 Official Certification Guide: Details tools used for cable identification and troubleshooting.

Cisco Networking Academy: Provides training on using toner probes and other cable testing tools.

Network+ Certification All-in-One Exam Guide: Explains the use of different tools for network cable identification and management.

Port 22 is used for SFTP (Secure File Transfer Protocol) and SCP (Secure Copy Protocol), which encrypt file transfers using SSH (Secure Shell). This ensures data is transmitted securely over the network.

•Why not the other options?

•Port 69 (B) – TFTP (Trivial File Transfer Protocol): Transfers files but is not secure (no encryption).

•Port 80 (C) – HTTP: Used for web traffic, not for file transfer.

•Port 3389 (D) – RDP (Remote Desktop Protocol): Used for remote desktop access, not file transfer.

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.

Direct Connect refers to a dedicated network connection between an on-premises network and a cloud service provider (such as AWS Direct Connect). This link bypasses the public internet, providing a more reliable and higher-bandwidth connection. It may not inherently include encryption because it relies on the security measures of the dedicated physical connection itself. In contrast, other options like VPN typically involve encryption as they traverse the public internet.