CompTIA Network+ N10-009 2025 — 60 Practice Questions with
Verified Answers
Series:
CrashCourses Professional Study Series
Author:
Dr Z. Moomba, MBChB, MRCPsych | BethelWellness Ltd
Exam Target:
CompTIA Network+
Year:
2025/2026
Format:
60 Questions with Verified Answers and Rationales
>
Author's Note:
This document is an original work produced for the CrashCourses Professional Study Series.
Clinical questions and professional scenarios were composed by Dr Z. Moomba based on current
exam objectives, published guidelines, and evidence-based sources (2024–2025). All patient
names, ages, and case details are fictional. Any resemblance to existing published Q&A banks is
coincidental. For personal study use only — not for reproduction or redistribution.
PART 1: CORE PRINCIPLES & FOUNDATIONS
A systems administrator at a regional surgical centre is diagnosing a workstation that fails to
load the internal Picture Archiving and Communication System (PACS). The administrator can
successfully ping the PACS server's IP address but gets an error when attempting to reach it
via its fully qualified domain name (FQDN). Which OSI layer is most likely the source of this
failure?
A) Network Layer
B) Transport Layer
C) Application Layer
D) Data Link Layer
,Answer: C
Rationale:
Lead: The inability to resolve an FQDN to an IP address indicates a Domain Name System
(DNS) failure. DNS is an application-level service, placing this issue at Layer 7 (Application
Layer) of the OSI model.
Discriminator: The successful ping using the IP address confirms that lower-level connectivity
(physical links, MAC addressing, and IP routing) is fully operational. The failure is specifically in
name resolution.
Distractor: Layer 3 (Network Layer) is incorrect because ICMP echo requests (pings) to the IP
address are succeeding, proving that end-to-end routing is functional.
Pearl: Examiner Insight: Always validate Layer 3 (IP connectivity) before troubleshooting Layer
7 (Application services like DNS or HTTP). [CompTIA N10-009 Objectives 2024]
A large tertiary care hospital is installing new cabling in its radiology department to handle 10
Gbps transmission of uncompressed MRI scans over a distance of 90 metres. To guarantee
these speeds across this specific distance, what is the minimum category of copper cabling
required?
A) Category 5e
B) Category 6
C) Category 6a
D) Category 7
Answer: C
Rationale:
Lead: Category 6a (Augmented) cable is specifically engineered to support 10GBASE-T
Ethernet at speeds of 10 Gbps over the full standard distance of 100 metres.
Discriminator: The distance of 90 metres is the critical factor. While other cables might support
high speeds over short runs, only Cat 6a (or higher) guarantees 10 Gbps at distances up to 100
metres.
Distractor: Category 6 can support 10 Gbps, but strictly up to a maximum distance of 55 metres
under ideal conditions. Beyond 55 metres, it is limited to 1 Gbps, making it unsuitable for a 90-
metre run.
Pearl: High-Yield Point: The "a" in Cat 6a stands for augmented, featuring thicker insulation
and tighter twists to eliminate alien crosstalk at high frequencies. [IEEE 802.3an Standard]
A senior network technician is configuring a newly installed managed switch in a busy intensive
care unit. To ensure that redundant uplinks to the core switch do not create broadcast storms,
which technology must be enabled?
,A) Open Shortest Path First (OSPF)
B) Spanning Tree Protocol (STP)
C) VLAN Trunking Protocol (VTP)
D) Dynamic Host Configuration Protocol (DHCP)
Answer: B
Rationale:
Lead: Spanning Tree Protocol (STP) is a Layer 2 protocol designed explicitly to prevent bridging
loops by identifying redundant links and placing them in a blocking state until they are needed.
Discriminator: The scenario describes preventing loops on "redundant uplinks" at the switch
level, which is the exact function of STP.
Distractor: OSPF is a Layer 3 routing protocol used to find the best path between subnets. It
does not operate at Layer 2 to prevent switching loops.
Pearl: Key Principle: Rapid Spanning Tree Protocol (RSTP / 802.1w) is the modern standard,
converging in milliseconds compared to the 30-50 seconds required by legacy STP (802.1D).
[IEEE 802.1w Standard]
A security audit at a maternity ward reveals that routine broadcast traffic from nursing station
computers is intermingling with traffic from critical neonatal monitoring devices on the same
physical switches. What is the most appropriate method to establish logical separation between
these two traffic types?
A) Transition to IPv6 addressing
B) Implement Virtual Local Area Networks (VLANs)
C) Apply MAC address filtering on the switch ports
D) Introduce a Network Address Translation (NAT) appliance
Answer: B
Rationale:
Lead: VLANs provide logical segmentation on a physical switch, effectively splitting it into
multiple distinct broadcast domains.
Discriminator: The requirement to logically isolate broadcast domains on shared physical
hardware makes VLAN assignment the standard architectural solution.
Distractor: MAC address filtering restricts which devices can connect to a port but does
nothing to separate the broadcast domains of devices that are already connected.
Pearl: Clinical Pearl: Segmenting critical medical devices from general user traffic using VLANs
is a fundamental security and performance requirement in healthcare IT. [NIST SP 800-53 Rev
5]
, A network engineer is planning a wireless upgrade for a crowded university teaching hospital.
The design requires a standard that operates exclusively in the 6 GHz spectrum to avoid
interference from legacy devices on the 2.4 GHz and 5 GHz bands, while accommodating high
client density. Which standard meets these criteria?
A) IEEE 802.11ac
B) IEEE 802.11ax (Wi-Fi 6E)
C) IEEE 802.11n
D) IEEE 802.11g
Answer: B
Rationale:
Lead: Wi-Fi 6E (an extension of the 802.11ax standard) is the first Wi-Fi standard to utilise the
new, uncongested 6 GHz frequency band.
Discriminator: The explicit demand for operation in the "6 GHz spectrum" to avoid 2.4 GHz and
5 GHz congestion uniquely identifies Wi-Fi 6E.
Distractor: Standard Wi-Fi 6 (802.11ax without the 'E') operates only in the 2.4 GHz and 5 GHz
bands. 802.11ac (Wi-Fi 5) operates only in the 5 GHz band.
Pearl: Examiner Insight: The "E" in Wi-Fi 6E stands for Extended, denoting the extension of
802.11ax capabilities into the pristine 6 GHz airspace. [Wi-Fi Alliance 2024]
A security administrator needs to remotely manage a branch clinic's firewall via a command-
line interface. To ensure all administrative commands and credentials are computationally
secure during transit, which protocol and port combination is required?
A) Telnet on TCP Port 23
B) Secure Shell (SSH) on TCP Port 22
C) Hypertext Transfer Protocol Secure (HTTPS) on TCP Port 443
D) Remote Desktop Protocol (RDP) on TCP Port 3389
Answer: B
Rationale:
Lead: Secure Shell (SSH) is the cryptographic network protocol used for secure, encrypted
command-line management of network devices, operating over TCP port 22.
Discriminator: The scenario requires a "command-line interface" that is "secure during transit",
which points directly to SSH over legacy unencrypted protocols.
Distractor: Telnet (TCP Port 23) also provides command-line access but transmits all data,
including administrative passwords, in plaintext, violating the security requirement.
Verified Answers
Series:
CrashCourses Professional Study Series
Author:
Dr Z. Moomba, MBChB, MRCPsych | BethelWellness Ltd
Exam Target:
CompTIA Network+
Year:
2025/2026
Format:
60 Questions with Verified Answers and Rationales
>
Author's Note:
This document is an original work produced for the CrashCourses Professional Study Series.
Clinical questions and professional scenarios were composed by Dr Z. Moomba based on current
exam objectives, published guidelines, and evidence-based sources (2024–2025). All patient
names, ages, and case details are fictional. Any resemblance to existing published Q&A banks is
coincidental. For personal study use only — not for reproduction or redistribution.
PART 1: CORE PRINCIPLES & FOUNDATIONS
A systems administrator at a regional surgical centre is diagnosing a workstation that fails to
load the internal Picture Archiving and Communication System (PACS). The administrator can
successfully ping the PACS server's IP address but gets an error when attempting to reach it
via its fully qualified domain name (FQDN). Which OSI layer is most likely the source of this
failure?
A) Network Layer
B) Transport Layer
C) Application Layer
D) Data Link Layer
,Answer: C
Rationale:
Lead: The inability to resolve an FQDN to an IP address indicates a Domain Name System
(DNS) failure. DNS is an application-level service, placing this issue at Layer 7 (Application
Layer) of the OSI model.
Discriminator: The successful ping using the IP address confirms that lower-level connectivity
(physical links, MAC addressing, and IP routing) is fully operational. The failure is specifically in
name resolution.
Distractor: Layer 3 (Network Layer) is incorrect because ICMP echo requests (pings) to the IP
address are succeeding, proving that end-to-end routing is functional.
Pearl: Examiner Insight: Always validate Layer 3 (IP connectivity) before troubleshooting Layer
7 (Application services like DNS or HTTP). [CompTIA N10-009 Objectives 2024]
A large tertiary care hospital is installing new cabling in its radiology department to handle 10
Gbps transmission of uncompressed MRI scans over a distance of 90 metres. To guarantee
these speeds across this specific distance, what is the minimum category of copper cabling
required?
A) Category 5e
B) Category 6
C) Category 6a
D) Category 7
Answer: C
Rationale:
Lead: Category 6a (Augmented) cable is specifically engineered to support 10GBASE-T
Ethernet at speeds of 10 Gbps over the full standard distance of 100 metres.
Discriminator: The distance of 90 metres is the critical factor. While other cables might support
high speeds over short runs, only Cat 6a (or higher) guarantees 10 Gbps at distances up to 100
metres.
Distractor: Category 6 can support 10 Gbps, but strictly up to a maximum distance of 55 metres
under ideal conditions. Beyond 55 metres, it is limited to 1 Gbps, making it unsuitable for a 90-
metre run.
Pearl: High-Yield Point: The "a" in Cat 6a stands for augmented, featuring thicker insulation
and tighter twists to eliminate alien crosstalk at high frequencies. [IEEE 802.3an Standard]
A senior network technician is configuring a newly installed managed switch in a busy intensive
care unit. To ensure that redundant uplinks to the core switch do not create broadcast storms,
which technology must be enabled?
,A) Open Shortest Path First (OSPF)
B) Spanning Tree Protocol (STP)
C) VLAN Trunking Protocol (VTP)
D) Dynamic Host Configuration Protocol (DHCP)
Answer: B
Rationale:
Lead: Spanning Tree Protocol (STP) is a Layer 2 protocol designed explicitly to prevent bridging
loops by identifying redundant links and placing them in a blocking state until they are needed.
Discriminator: The scenario describes preventing loops on "redundant uplinks" at the switch
level, which is the exact function of STP.
Distractor: OSPF is a Layer 3 routing protocol used to find the best path between subnets. It
does not operate at Layer 2 to prevent switching loops.
Pearl: Key Principle: Rapid Spanning Tree Protocol (RSTP / 802.1w) is the modern standard,
converging in milliseconds compared to the 30-50 seconds required by legacy STP (802.1D).
[IEEE 802.1w Standard]
A security audit at a maternity ward reveals that routine broadcast traffic from nursing station
computers is intermingling with traffic from critical neonatal monitoring devices on the same
physical switches. What is the most appropriate method to establish logical separation between
these two traffic types?
A) Transition to IPv6 addressing
B) Implement Virtual Local Area Networks (VLANs)
C) Apply MAC address filtering on the switch ports
D) Introduce a Network Address Translation (NAT) appliance
Answer: B
Rationale:
Lead: VLANs provide logical segmentation on a physical switch, effectively splitting it into
multiple distinct broadcast domains.
Discriminator: The requirement to logically isolate broadcast domains on shared physical
hardware makes VLAN assignment the standard architectural solution.
Distractor: MAC address filtering restricts which devices can connect to a port but does
nothing to separate the broadcast domains of devices that are already connected.
Pearl: Clinical Pearl: Segmenting critical medical devices from general user traffic using VLANs
is a fundamental security and performance requirement in healthcare IT. [NIST SP 800-53 Rev
5]
, A network engineer is planning a wireless upgrade for a crowded university teaching hospital.
The design requires a standard that operates exclusively in the 6 GHz spectrum to avoid
interference from legacy devices on the 2.4 GHz and 5 GHz bands, while accommodating high
client density. Which standard meets these criteria?
A) IEEE 802.11ac
B) IEEE 802.11ax (Wi-Fi 6E)
C) IEEE 802.11n
D) IEEE 802.11g
Answer: B
Rationale:
Lead: Wi-Fi 6E (an extension of the 802.11ax standard) is the first Wi-Fi standard to utilise the
new, uncongested 6 GHz frequency band.
Discriminator: The explicit demand for operation in the "6 GHz spectrum" to avoid 2.4 GHz and
5 GHz congestion uniquely identifies Wi-Fi 6E.
Distractor: Standard Wi-Fi 6 (802.11ax without the 'E') operates only in the 2.4 GHz and 5 GHz
bands. 802.11ac (Wi-Fi 5) operates only in the 5 GHz band.
Pearl: Examiner Insight: The "E" in Wi-Fi 6E stands for Extended, denoting the extension of
802.11ax capabilities into the pristine 6 GHz airspace. [Wi-Fi Alliance 2024]
A security administrator needs to remotely manage a branch clinic's firewall via a command-
line interface. To ensure all administrative commands and credentials are computationally
secure during transit, which protocol and port combination is required?
A) Telnet on TCP Port 23
B) Secure Shell (SSH) on TCP Port 22
C) Hypertext Transfer Protocol Secure (HTTPS) on TCP Port 443
D) Remote Desktop Protocol (RDP) on TCP Port 3389
Answer: B
Rationale:
Lead: Secure Shell (SSH) is the cryptographic network protocol used for secure, encrypted
command-line management of network devices, operating over TCP port 22.
Discriminator: The scenario requires a "command-line interface" that is "secure during transit",
which points directly to SSH over legacy unencrypted protocols.
Distractor: Telnet (TCP Port 23) also provides command-line access but transmits all data,
including administrative passwords, in plaintext, violating the security requirement.
