CompTIA Network+ Exam Prep 2026 Comprehensive Networking Certification Review Practice Questions with Detailed Explanations

CompTIA Network+ Exam Prep 2026 Comprehensive
Networking Certification Review Practice Questions
with Detailed Explanations

DOMAIN 1: NETWORKING CONCEPTS (23%) — Questions 1-23


Question 1
At which layer of the OSI model does routing occur?
A) Data Link Layer
B) Network Layer
C) Transport Layer
D) Session Layer
Answer: B
Rationale: Routing occurs at the Network Layer (Layer 3) of the OSI model. This
layer is responsible for logical addressing, path determination, and routing of data
packets between different networks. Routers operate at this layer to forward
packets based on IP addresses. The Data Link Layer (Layer 2) handles switching
within a local network, while the Transport Layer (Layer 4) manages end-to-end
communication and data flow control.


Question 2
Which protocol is used to translate domain names to IP addresses?
A) DHCP
B) DNS
C) ARP
D) NTP
Answer: B
Rationale: The Domain Name System (DNS) is the protocol and service that
translates human-readable domain names (like www.example.com) into IP
addresses that computers use to communicate. DHCP assigns IP addresses

,dynamically, ARP resolves IP addresses to MAC addresses, and NTP synchronizes
time across network devices.


Question 3
Which port does HTTPS use by default?
A) 80
B) 443
C) 22
D) 25
Answer: B
Rationale: HTTPS (HTTP Secure) uses TCP port 443 by default for encrypted
web traffic. Port 80 is used for standard unencrypted HTTP. Port 22 is used for
SSH (Secure Shell), and Port 25 is used for SMTP (Simple Mail Transfer
Protocol).


Question 4
Which network topology provides the highest fault tolerance by connecting each
node to every other node?
A) Star topology
B) Ring topology
C) Mesh topology
D) Bus topology
Answer: C
Rationale: In a full mesh topology, every node is directly connected to every other
node, providing the highest level of redundancy and fault tolerance. If one link
fails, traffic can be rerouted through alternative paths. Star topology uses a central
hub; ring topology connects nodes in a circular fashion; and bus topology uses a
single shared cable.


Question 5
Which OSI model layer is responsible for data segmentation and reassembly?

,A) Network Layer
B) Data Link Layer
C) Transport Layer
D) Session Layer
Answer: C
Rationale: The Transport Layer (Layer 4) is responsible for segmenting data into
smaller units for transmission and reassembling them at the destination. It provides
end-to-end communication services, including flow control, error checking, and
data segmentation using protocols like TCP and UDP.


Question 6
A network administrator is configuring a new switch. Which networking device
separates collision domains at the Data Link Layer?
A) Hub
B) Bridge
C) Router
D) Switch
Answer: D
Rationale: A switch separates collision domains at the Data Link Layer (Layer 2).
Each port on a switch represents its own collision domain, allowing full-duplex
communication and reducing collisions. Hubs do not separate collision domains;
routers separate broadcast domains; bridges connect network segments.


Question 7
Which of the following is a characteristic of the TCP protocol?
A) Connectionless
B) Unreliable
C) Connection-oriented with flow control
D) No error recovery
Answer: C

, Rationale: TCP (Transmission Control Protocol) is a connection-oriented protocol
that provides reliable, ordered delivery of data with flow control and error
recovery. It establishes a three-way handshake before data transmission. UDP, by
contrast, is connectionless and unreliable.


Question 8
A network uses the 192.168.1.0/24 subnet. How many usable host addresses are
available in this subnet?
A) 254
B) 255
C) 256
D) 128
Answer: A
Rationale: A /24 subnet has a subnet mask of 255.255.255.0, providing 256 total
addresses. Of these, the network address (192.168.1.0) and the broadcast address
(192.168.1.255) are not usable for hosts. This leaves 254 usable host addresses
(256 - 2 = 254).


Question 9
Which cloud service model provides users with access to operating systems and
applications but not the underlying hardware infrastructure?
A) IaaS
B) PaaS
C) SaaS
D) DaaS
Answer: B
Rationale: Platform as a Service (PaaS) provides a platform allowing customers to
develop, run, and manage applications without the complexity of building and
maintaining the underlying infrastructure. Users control the operating systems and
applications but not the hardware. IaaS provides raw infrastructure, and SaaS
provides complete software applications.