WGU D315 Network and Security
Pre-Assessment, Objective Assessment
& Final Exam
Updated 2025/2026
Verified Exam Sets
Latest Questions and Answers
,Network and Security- Foundations- D315
PA, OA & FINALS
1. What is TCP/IP?Correct Answer
TCP/IP stands for Transmission Control Protocol/Internet Protocol, which is a
suite of communication protocols used to interconnect network devices on the
internet.
2. What is the role of the Application Layer in the TCP/IP model?Correct
Answer
The Application Layer is responsible for communication protocols between
nodes, including protocols like HTTP, HTTPS, SSH, and NTP.
3. Which protocols are part of the Transport Layer in the TCP/IP
model?Correct Answer
The Transport Layer includes the Transmission Control Protocol (TCP) and the
User Datagram Protocol (UDP).
4. What does the Network Layer in the TCP/IP model do?Correct Answer
The Network Layer defines logical transmission protocols for the entire
network and includes protocols such as Internet Protocol (IP), Internet Control
Message Protocol (ICMP), and Address Resolution Protocol (ARP).
5. What is the purpose of the Network Interface Layer in the TCP/IP
model?Correct Answer
The Network Interface Layer establishes how data should be physically sent
through the network.
6. What is the OSI Model?Correct Answer
The OSI (Open Systems Interconnection) Model is a conceptual framework
used to understand and implement network protocols in seven layers.
7. What devices operate at the Physical Layer (Layer 1) of the OSI
Model?Correct Answer
,Devices at the Physical Layer include hubs, repeaters, modems, and physical
cabling.
8. What is the function of the Data Link Layer (Layer 2) in the OSI
Model?Correct Answer
The Data Link Layer ensures error-free delivery of data and uses devices like
switches, bridges, and network interface cards (NICs).
9. What is the primary responsibility of the Network Layer (Layer 3) in
the OSI Model?Correct Answer
The Network Layer is responsible for data transmission between different
networks and routing data packets using devices like routers.
10. How does the Transport Layer (Layer 4) ensure reliable data
transfer?Correct Answer
The Transport Layer provides flow control, acknowledgment, error correction,
segmentation, reassembly, and sequencing.
11. What is the function of the Session Layer (Layer 5)?Correct Answer
The Session Layer manages connection establishment, session maintenance,
and authentication.
12. What tasks are handled by the Presentation Layer (Layer 6)?Correct
Answer
The Presentation Layer translates and formats data for transmission and
handles data encryption for security.
13. Which layer of the OSI model manages network applications like
HTTP and FTP?Correct Answer
The Application Layer (Layer 7) handles network applications and their data
production.
14. What is the function of a Hub?Correct Answer
A Hub connects devices on an Ethernet network, splits bandwidth among
devices, and broadcasts data to all connected devices without packet filtering.
15. What does a Switch do in a network?Correct Answer
A Switch provides device connectivity in a local network, uses MAC addresses
to deliver messages, and creates dedicated connections between
communicating devices.
, 16. What is the primary role of a Router?Correct Answer
A Router interconnects multiple networks, operates at the Network Layer, and
directs data packets to their destination.
17. What is a Wireless Access Point (WAP)?Correct Answer
A WAP extends wired networks to wireless connections and serves as a central
connection point for wireless devices.
18. What is the purpose of a Patch Panel?Correct Answer
A Patch Panel acts as a junction point for organizing twisted-pair and fiber
cables.
19. What is a Firewall?Correct Answer
A Firewall is a security device or software that protects networks by blocking
unwanted connections and preventing unauthorized access.
20. What is the role of a Modem?Correct Answer
A Modem connects a LAN to an Internet Service Provider (ISP) and converts
digital signals to analog and vice versa.
21. What is a Network Interface Card (NIC)?Correct Answer
A NIC connects devices to a LAN and has a unique physical address called a
MAC address.
22. What is the function of a Bridge in networking?Correct Answer
A Bridge connects two or more networks, forwards data, and analyzes traffic.
23. What does a Repeater do?Correct Answer
A Repeater amplifies signals to extend their transmission distance.
24. What are the differences between Cat 5 and Cat 6 cables?Correct
Answer
Cat 5 supports up to 100 Mbps over 100 meters.
Cat 6 supports 1 Gbps up to 100 meters or 10 Gbps up to 55 meters.
25. What is the purpose of fiber-optic cable?Correct Answer
Fiber-optic cable uses light to transmit data at high speeds over long distances.
Pre-Assessment, Objective Assessment
& Final Exam
Updated 2025/2026
Verified Exam Sets
Latest Questions and Answers
,Network and Security- Foundations- D315
PA, OA & FINALS
1. What is TCP/IP?Correct Answer
TCP/IP stands for Transmission Control Protocol/Internet Protocol, which is a
suite of communication protocols used to interconnect network devices on the
internet.
2. What is the role of the Application Layer in the TCP/IP model?Correct
Answer
The Application Layer is responsible for communication protocols between
nodes, including protocols like HTTP, HTTPS, SSH, and NTP.
3. Which protocols are part of the Transport Layer in the TCP/IP
model?Correct Answer
The Transport Layer includes the Transmission Control Protocol (TCP) and the
User Datagram Protocol (UDP).
4. What does the Network Layer in the TCP/IP model do?Correct Answer
The Network Layer defines logical transmission protocols for the entire
network and includes protocols such as Internet Protocol (IP), Internet Control
Message Protocol (ICMP), and Address Resolution Protocol (ARP).
5. What is the purpose of the Network Interface Layer in the TCP/IP
model?Correct Answer
The Network Interface Layer establishes how data should be physically sent
through the network.
6. What is the OSI Model?Correct Answer
The OSI (Open Systems Interconnection) Model is a conceptual framework
used to understand and implement network protocols in seven layers.
7. What devices operate at the Physical Layer (Layer 1) of the OSI
Model?Correct Answer
,Devices at the Physical Layer include hubs, repeaters, modems, and physical
cabling.
8. What is the function of the Data Link Layer (Layer 2) in the OSI
Model?Correct Answer
The Data Link Layer ensures error-free delivery of data and uses devices like
switches, bridges, and network interface cards (NICs).
9. What is the primary responsibility of the Network Layer (Layer 3) in
the OSI Model?Correct Answer
The Network Layer is responsible for data transmission between different
networks and routing data packets using devices like routers.
10. How does the Transport Layer (Layer 4) ensure reliable data
transfer?Correct Answer
The Transport Layer provides flow control, acknowledgment, error correction,
segmentation, reassembly, and sequencing.
11. What is the function of the Session Layer (Layer 5)?Correct Answer
The Session Layer manages connection establishment, session maintenance,
and authentication.
12. What tasks are handled by the Presentation Layer (Layer 6)?Correct
Answer
The Presentation Layer translates and formats data for transmission and
handles data encryption for security.
13. Which layer of the OSI model manages network applications like
HTTP and FTP?Correct Answer
The Application Layer (Layer 7) handles network applications and their data
production.
14. What is the function of a Hub?Correct Answer
A Hub connects devices on an Ethernet network, splits bandwidth among
devices, and broadcasts data to all connected devices without packet filtering.
15. What does a Switch do in a network?Correct Answer
A Switch provides device connectivity in a local network, uses MAC addresses
to deliver messages, and creates dedicated connections between
communicating devices.
, 16. What is the primary role of a Router?Correct Answer
A Router interconnects multiple networks, operates at the Network Layer, and
directs data packets to their destination.
17. What is a Wireless Access Point (WAP)?Correct Answer
A WAP extends wired networks to wireless connections and serves as a central
connection point for wireless devices.
18. What is the purpose of a Patch Panel?Correct Answer
A Patch Panel acts as a junction point for organizing twisted-pair and fiber
cables.
19. What is a Firewall?Correct Answer
A Firewall is a security device or software that protects networks by blocking
unwanted connections and preventing unauthorized access.
20. What is the role of a Modem?Correct Answer
A Modem connects a LAN to an Internet Service Provider (ISP) and converts
digital signals to analog and vice versa.
21. What is a Network Interface Card (NIC)?Correct Answer
A NIC connects devices to a LAN and has a unique physical address called a
MAC address.
22. What is the function of a Bridge in networking?Correct Answer
A Bridge connects two or more networks, forwards data, and analyzes traffic.
23. What does a Repeater do?Correct Answer
A Repeater amplifies signals to extend their transmission distance.
24. What are the differences between Cat 5 and Cat 6 cables?Correct
Answer
Cat 5 supports up to 100 Mbps over 100 meters.
Cat 6 supports 1 Gbps up to 100 meters or 10 Gbps up to 55 meters.
25. What is the purpose of fiber-optic cable?Correct Answer
Fiber-optic cable uses light to transmit data at high speeds over long distances.
