Practice Free N10-009 Exam Online Questions
Question #21
A VoIP phone is plugged in to a port but cannot receive calls.
Which of the following needs to be done on the port to address the issue?
- A . Trunk all VLANs on the port.
- B . Configure the native VLAN.
- C . Tag the traffic to voice VLAN.
- D . Disable VLANs.
Correct Answer: C
C
Explanation:
Understanding VoIP and VLANs:
VoIP (Voice over IP) phones often use VLANs (Virtual Local Area Networks) to separate voice traffic from data traffic for improved performance and security.
Tagging Traffic to Voice VLAN:
Voice VLAN Configuration: The port on the switch needs to be configured to tag traffic for the specific voice VLAN. This ensures that voice packets are prioritized and handled correctly.
VLAN Tagging: VLAN tagging allows the switch to identify and separate voice traffic from other types of traffic on the network, reducing latency and jitter for VoIP communications.
Comparison with Other Options:
Trunk all VLANs on the port: Trucking all VLANs is typically used for links between switches, not for individual device ports.
Configure the native VLAN: The native VLAN is for untagged traffic and does not address the need for separating and prioritizing voice traffic.
Disable VLANs: Disabling VLANs would mix voice and data traffic, leading to potential performance issues and lack of traffic separation.
Implementation:
Configure the switch port connected to the VoIP phone to tag the traffic for the designated voice VLAN, ensuring proper network segmentation and quality of service.
Reference: CompTIA Network+ study materials on VLAN configuration and VoIP implementation.
C
Explanation:
Understanding VoIP and VLANs:
VoIP (Voice over IP) phones often use VLANs (Virtual Local Area Networks) to separate voice traffic from data traffic for improved performance and security.
Tagging Traffic to Voice VLAN:
Voice VLAN Configuration: The port on the switch needs to be configured to tag traffic for the specific voice VLAN. This ensures that voice packets are prioritized and handled correctly.
VLAN Tagging: VLAN tagging allows the switch to identify and separate voice traffic from other types of traffic on the network, reducing latency and jitter for VoIP communications.
Comparison with Other Options:
Trunk all VLANs on the port: Trucking all VLANs is typically used for links between switches, not for individual device ports.
Configure the native VLAN: The native VLAN is for untagged traffic and does not address the need for separating and prioritizing voice traffic.
Disable VLANs: Disabling VLANs would mix voice and data traffic, leading to potential performance issues and lack of traffic separation.
Implementation:
Configure the switch port connected to the VoIP phone to tag the traffic for the designated voice VLAN, ensuring proper network segmentation and quality of service.
Reference: CompTIA Network+ study materials on VLAN configuration and VoIP implementation.
Question #22
A company recently implemented a videoconferencing system that utilizes large amounts of bandwidth. Users start reporting slow internet speeds and an overall decrease in network performance.
Which of the following are most likely the causes of the network performance issues? (Select two)
- A . DNS misconfiguration
- B . Inadequate network security
- C . Malware or a virus
- D . Outdated software
- E . Incorrect QoS settings
- F . Network congestion
Correct Answer: E,F
E,F
Explanation:
When high-bandwidth services like videoconferencing are introduced, two primary factors may degrade performance:
Incorrect QoS Settings (E): QoS (Quality of Service) is used to prioritize traffic. If not configured correctly, critical services like video may not get the necessary bandwidth and prioritization.
Network Congestion (F): Video services consume large amounts of data. If the network doesn’t have sufficient bandwidth or is not segmented properly, congestion will slow down all services.
DNS misconfiguration (A) would affect name resolution, not bandwidth.
Malware (C) could degrade performance, but is not tied to the described scenario.
Outdated software (D) may affect performance in some cases, but not directly linked to network congestion in this case.
Inadequate network security (B) isn’t likely to cause general slowness related to video traffic.
✅ So, the most likely culprits are
E. Incorrect QoS settings and
F. Network congestion.
Reference: CompTIA Network+ N10-009 Official Study Guide ― Objective 2.5: "Explain common performance concepts and issues."
E,F
Explanation:
When high-bandwidth services like videoconferencing are introduced, two primary factors may degrade performance:
Incorrect QoS Settings (E): QoS (Quality of Service) is used to prioritize traffic. If not configured correctly, critical services like video may not get the necessary bandwidth and prioritization.
Network Congestion (F): Video services consume large amounts of data. If the network doesn’t have sufficient bandwidth or is not segmented properly, congestion will slow down all services.
DNS misconfiguration (A) would affect name resolution, not bandwidth.
Malware (C) could degrade performance, but is not tied to the described scenario.
Outdated software (D) may affect performance in some cases, but not directly linked to network congestion in this case.
Inadequate network security (B) isn’t likely to cause general slowness related to video traffic.
✅ So, the most likely culprits are
E. Incorrect QoS settings and
F. Network congestion.
Reference: CompTIA Network+ N10-009 Official Study Guide ― Objective 2.5: "Explain common performance concepts and issues."
Question #23
Which of the following internal routing protocols is best characterized as having fast convergence and being loop-free?
- A . BGP
- B . STP
- C . OSPF
- D . RIP
Correct Answer: C
C
Explanation:
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.
C
Explanation:
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.
Question #24
Which of the following ports should a network administrator enable for encrypted login to a network switch?
- A . 22
- B . 23
- C . 80
- D . 123
Correct Answer: A
A
Explanation:
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
Explanation:
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.”
Question #25
An IT department is considering implementing a SIEM solution to improve network security. The department wants to ensure that the SIEM system is able to ingest and analyze logs from all of the company’s core devices.
Which of the following is the most important consideration when selecting a SIEM solution?
- A . Easy to manage
- B . Cost
- C . Compatibility
- D . Features
Correct Answer: C
C
Explanation:
The correct answer is C. Compatibility. A SIEM is only effective if it can successfully collect, normalize, and analyze data from the systems the organization relies on. Since the question specifically says the department wants the SIEM to ingest and analyze logs from all core devices, the
most important factor is whether the SIEM is compatible with those devices, their log formats, and their supported methods of exporting events.
This includes support for common logging methods such as syslog, SNMP traps, API integrations, agent-based collection, and vendor-specific event formats. Even a SIEM with excellent features will not deliver value if it cannot properly receive and interpret logs from firewalls, routers, switches, servers, and security appliances already in use.
The other choices matter, but they come after compatibility. Ease of management is helpful for daily operations. Cost is always a practical concern. Features can improve visibility and automation. However, none of those benefits matter much if the SIEM cannot integrate with the organization’s actual environment.
For Network+ exam purposes, when log ingestion across many device types is the requirement, the top selection criterion is compatibility. Without that foundation, correlation, alerting, and security analysis will be incomplete.
C
Explanation:
The correct answer is C. Compatibility. A SIEM is only effective if it can successfully collect, normalize, and analyze data from the systems the organization relies on. Since the question specifically says the department wants the SIEM to ingest and analyze logs from all core devices, the
most important factor is whether the SIEM is compatible with those devices, their log formats, and their supported methods of exporting events.
This includes support for common logging methods such as syslog, SNMP traps, API integrations, agent-based collection, and vendor-specific event formats. Even a SIEM with excellent features will not deliver value if it cannot properly receive and interpret logs from firewalls, routers, switches, servers, and security appliances already in use.
The other choices matter, but they come after compatibility. Ease of management is helpful for daily operations. Cost is always a practical concern. Features can improve visibility and automation. However, none of those benefits matter much if the SIEM cannot integrate with the organization’s actual environment.
For Network+ exam purposes, when log ingestion across many device types is the requirement, the top selection criterion is compatibility. Without that foundation, correlation, alerting, and security analysis will be incomplete.
Question #26
Which of the following types of connectors allows the transmission of network data through a coaxial cable?
- A . SC
- B . MPO
- C . BNC
- D . RJ11
Correct Answer: C
C
Explanation:
The right answer is C. BNC. A BNC connector is associated with coaxial cabling, which has been used for certain networking, video, and radio frequency applications. In networking history, coax with BNC connectors was common in older Ethernet implementations such as 10BASE2.
The other choices point to different media types. SC is a fiber optic connector. MPO is also a fiber connector, usually for high-density fiber connections. RJ11 is commonly used for telephone wiring rather than coaxial network cabling. Since the question specifically asks about transmission through a coaxial cable, BNC is the only match.
This is one of those basic media and connector recognition questions that CompTIA likes to include. The goal is to connect the connector type to the cabling standard it belongs with. When you see coax, the classic connector to remember is BNC. When you see fiber, think of connectors such as SC, LC, ST, or MPO. When you see telephone pairs, RJ11 is the common answer.
So the clean way to solve this one is by matching cable type to connector type. Coaxial cable goes with BNC.
C
Explanation:
The right answer is C. BNC. A BNC connector is associated with coaxial cabling, which has been used for certain networking, video, and radio frequency applications. In networking history, coax with BNC connectors was common in older Ethernet implementations such as 10BASE2.
The other choices point to different media types. SC is a fiber optic connector. MPO is also a fiber connector, usually for high-density fiber connections. RJ11 is commonly used for telephone wiring rather than coaxial network cabling. Since the question specifically asks about transmission through a coaxial cable, BNC is the only match.
This is one of those basic media and connector recognition questions that CompTIA likes to include. The goal is to connect the connector type to the cabling standard it belongs with. When you see coax, the classic connector to remember is BNC. When you see fiber, think of connectors such as SC, LC, ST, or MPO. When you see telephone pairs, RJ11 is the common answer.
So the clean way to solve this one is by matching cable type to connector type. Coaxial cable goes with BNC.
Question #27
A customer is adding fiber connectivity between adjacent buildings. A technician terminates the multimode cable to the fiber patch panel. After the technician connects the fiber patch cable, the indicator light does not turn on.
Which of the following should a technician try first to troubleshoot this issue?
- A . Reverse the fibers.
- B . Reterminate the fibers.
- C . Verify the fiber size.
- D . Examine the cable runs for visual faults.
Correct Answer: A
A
Explanation:
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.
Reference: CompTIA Network+ study materials.
A
Explanation:
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.
Reference: CompTIA Network+ study materials.
Question #27
A customer is adding fiber connectivity between adjacent buildings. A technician terminates the multimode cable to the fiber patch panel. After the technician connects the fiber patch cable, the indicator light does not turn on.
Which of the following should a technician try first to troubleshoot this issue?
- A . Reverse the fibers.
- B . Reterminate the fibers.
- C . Verify the fiber size.
- D . Examine the cable runs for visual faults.
Correct Answer: A
A
Explanation:
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.
Reference: CompTIA Network+ study materials.
A
Explanation:
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.
Reference: CompTIA Network+ study materials.
Question #29
A network administrator is unable to ping a remote server from a newly connected workstation that has been added to the network. Ping to 127.0.0.1 on the workstation is failing.
Which of the following should the administrator perform to diagnose the problem?
- A . Verify the NIC interface status.
- B . Verify the network is not congested.
- C . Verify the router is not dropping packets.
- D . Verify that DNS is resolving correctly.
Correct Answer: A
A
Explanation:
The failure of a ping to 127.0.0.1 (the loopback address) indicates a problem with the workstation’s TCP/IP stack or network interface card (NIC). Since 127.0.0.1 is a local address, the issue is not related to the network, router, or DNS. The first step in diagnosing this issue is to verify the NIC interface status to ensure the network adapter is functioning and properly configured.
Why not Verify the network is not congested? Network congestion affects external connectivity, not the loopback address.
Why not Verify the router is not dropping packets? Router issues are irrelevant since the loopback ping fails locally.
Why not Verify that DNS is resolving correctly? DNS resolution is not involved in pinging 127.0.0.1, which uses a direct IP address.
Reference: CompTIA Network+ N10-009 Objective 5.2: Explain the troubleshooting methodology. The CompTIA Network+ Study Guide (e.g., Chapter 13: Network Troubleshooting) emphasizes that a failed loopback ping indicates a local TCP/IP stack or NIC issue, and checking the NIC status is the first diagnostic step.
A
Explanation:
The failure of a ping to 127.0.0.1 (the loopback address) indicates a problem with the workstation’s TCP/IP stack or network interface card (NIC). Since 127.0.0.1 is a local address, the issue is not related to the network, router, or DNS. The first step in diagnosing this issue is to verify the NIC interface status to ensure the network adapter is functioning and properly configured.
Why not Verify the network is not congested? Network congestion affects external connectivity, not the loopback address.
Why not Verify the router is not dropping packets? Router issues are irrelevant since the loopback ping fails locally.
Why not Verify that DNS is resolving correctly? DNS resolution is not involved in pinging 127.0.0.1, which uses a direct IP address.
Reference: CompTIA Network+ N10-009 Objective 5.2: Explain the troubleshooting methodology. The CompTIA Network+ Study Guide (e.g., Chapter 13: Network Troubleshooting) emphasizes that a failed loopback ping indicates a local TCP/IP stack or NIC issue, and checking the NIC status is the first diagnostic step.
Question #30
Which of the following impacts the availability of a web-based customer portal?
- A . MAC flooding
- B . ARP spoofing
- C . DoS
- D . Rogue devices
Correct Answer: C
C
Explanation:
A DoS (Denial of Service) attack directly targets availability, one of the core security goals (CIA triad) emphasized in Network+ (N10-009) security objectives. A web-based customer portal depends on reachable services (web servers, load balancers, DNS, upstream bandwidth). In a DoS, an attacker attempts to overwhelm the portal or its supporting infrastructure―consuming bandwidth, exhausting server resources, or saturating state tables―so legitimate users cannot connect or experience severe degradation. This is the most direct and common scenario where “availability” is impacted for a public web service.
MAC flooding aims to overflow a switch’s CAM table and can lead to traffic being broadcast out ports, which is more commonly associated with enabling sniffing or disruption within a local switched network segment―not typically the primary attack described for a web portal’s availability. ARP spoofing is a local network man-in-the-middle/redirection technique affecting integrity/confidentiality and potentially availability for local hosts, but it is not the best match for a public portal availability impact. Rogue devices can introduce risk, but the option is broad and indirect; DoS is the clearest availability-focused threat.
C
Explanation:
A DoS (Denial of Service) attack directly targets availability, one of the core security goals (CIA triad) emphasized in Network+ (N10-009) security objectives. A web-based customer portal depends on reachable services (web servers, load balancers, DNS, upstream bandwidth). In a DoS, an attacker attempts to overwhelm the portal or its supporting infrastructure―consuming bandwidth, exhausting server resources, or saturating state tables―so legitimate users cannot connect or experience severe degradation. This is the most direct and common scenario where “availability” is impacted for a public web service.
MAC flooding aims to overflow a switch’s CAM table and can lead to traffic being broadcast out ports, which is more commonly associated with enabling sniffing or disruption within a local switched network segment―not typically the primary attack described for a web portal’s availability. ARP spoofing is a local network man-in-the-middle/redirection technique affecting integrity/confidentiality and potentially availability for local hosts, but it is not the best match for a public portal availability impact. Rogue devices can introduce risk, but the option is broad and indirect; DoS is the clearest availability-focused threat.