CompTIA Network+® Certification Exam 2026 Latest Comprehensive Study Guide Practice Questions, Networking Review, Verified Answers & Success Preparation Workbook

CompTIA Network+® Certification Exam 2026 Latest
Comprehensive Study Guide Practice Questions,
Networking Review, Verified Answers & Success
Preparation Workbook

INTRODUCTION
Exam Overview
The CompTIA Network+ N10-009 exam is a vendor-neutral certification that
validates the knowledge and skills required to design, configure, manage, and
troubleshoot wired and wireless networks.
What's New in N10-009 (2026)
The N10-009 update added stronger emphasis on:
• SD-WAN & SASE - Software-defined wide-area networking and Secure
Access Service Edge
• Zero Trust networking - Zero-trust principles, microsegmentation, and
identity-aware networking
• Expanded IPv6 - IPv6 deployment, addressing, and dual-stack
• Modern wireless - Wi-Fi 6 (802.11ax) and 6E
• Cloud networking - VPCs, transit gateways, cloud interconnect
concepts
• Infrastructure as Code (IaC) - Automating infrastructure management


DOMAIN 1: NETWORKING CONCEPTS (23%)
Questions 1–23


Question 1
At which layer of the OSI model does a router primarily operate?

,A) Layer 1 — Physical
B) Layer 2 — Data Link
C) Layer 3 — Network
D) Layer 4 — Transport
Answer: C) Layer 3 — Network
Rationale: Routers operate at the Network layer (Layer 3) of the OSI model,
where they use logical addressing (IP addresses) to determine the best path
for forwarding packets between networks. Hubs and repeaters operate at
Layer 1 (A). Switches and bridges operate at Layer 2 (B). TCP and UDP
operate at Layer 4 (D).


Question 2
Which of the following protocols uses TCP port 443 by default?
A) HTTP
B) HTTPS
C) FTP
D) SSH
Answer: B) HTTPS
Rationale: HTTPS (HTTP Secure) uses TCP port 443 by default for encrypted
web traffic. HTTP uses port 80 (A). FTP uses ports 20 and 21 (C). SSH uses
port 22 (D).


Question 3
A network administrator needs to divide the 192.168.1.0/24 network into
four equal subnets. What is the new subnet mask?
A) 255.255.255.128
B) 255.255.255.192
C) 255.255.255.224
D) 255.255.255.240
Answer: B) 255.255.255.192

,Rationale: Dividing a /24 network into 4 subnets requires borrowing 2 bits
(2² = 4 subnets), making the new prefix length /26. A /26 subnet mask is
255.255.255.192. Option A (/25) creates 2 subnets. Option C (/27) creates 8
subnets. Option D (/28) creates 16 subnets.


Question 4
Which of the following is a private IPv4 address range?
A) 172.32.0.0 – 172.63.255.255
B) 10.0.0.0 – 10.255.255.255
C) 169.254.0.0 – 169.254.255.255
D) 192.0.2.0 – 192.0.2.255
Answer: B) 10.0.0.0 – 10.255.255.255
Rationale: The private IPv4 address ranges are 10.0.0.0/8, 172.16.0.0/12,
and 192.168.0.0/16. 172.32.0.0 (A) is outside the private 172.16.0.0/12 range.
169.254.0.0/16 (C) is APIPA (link-local), not private. 192.0.2.0/24 (D) is
reserved for documentation (TEST-NET).


Question 5
What is the primary function of the Address Resolution Protocol (ARP)?
A) To resolve domain names to IP addresses
B) To resolve IP addresses to MAC addresses
C) To assign IP addresses dynamically
D) To route packets between networks
Answer: B) To resolve IP addresses to MAC addresses
Rationale: ARP resolves IP addresses to MAC (Media Access Control)
addresses on a local network segment, allowing devices to communicate at
the Data Link layer. DNS resolves domain names to IP addresses (A). DHCP
assigns IP addresses dynamically (C). Routing is performed by routers (D).


Question 6

, A workstation can ping 8.8.8.8 but cannot browse to websites by name. Other
devices on the same network browse normally. What should the technician
investigate first?
A) The building's power supply
B) The cable type between the monitor and PC
C) The workstation DNS configuration or name-resolution cache
D) The internet provider's global routing table
Answer: C) The workstation DNS configuration or name-resolution cache
Rationale: Successful ping to an IP address shows basic IP connectivity.
Failure by name points first to DNS or local name-resolution settings,
especially because other devices work. Power supply (A) would affect more
than name resolution. Monitor cable (B) is unrelated. The provider's routing
table (D) is too broad and inconsistent with other devices working.


Question 7
Which of the following is a connectionless protocol?
A) TCP
B) UDP
C) HTTP
D) FTP
Answer: B) UDP
Rationale: UDP (User Datagram Protocol) is connectionless—it does not
establish a connection before sending data and does not guarantee delivery.
TCP (A) is connection-oriented. HTTP (C) and FTP (D) use TCP and are
therefore connection-oriented.


Question 8
What is the prefix length for the subnet mask 255.255.255.0?
A) /8
B) /16