30 MCQs on Computer Networking with Detailed Explanation

Practicing computer network MCQs is essential for mastering networking concepts and protocols, which are crucial for various IT certifications like CCNA, CompTIA Network+, and CCNP. These multiple-choice questions help reinforce knowledge, identify weak areas, and enhance problem-solving skills.

Engaging with MCQs prepares candidates for exams and builds confidence in applying theoretical knowledge to real-world scenarios, making it a beneficial practice for anyone pursuing a career in networking or cybersecurity. This article contains 30 important MCQs on computer networks along with detailed solutions.

We have divided the MCQs into 3 difficulty levels- Easy, Medium, and Hard. Students can practice these MCQs based on their preparation and current knowledge. We will be adding more MCQs in the future so that students can practice more.

Easy MCQs on Computer Networks

Here are some easy multiple-choice questions on computer networks. If you are a beginner, you should be able to answer these questions.

1. What defines a computer network?   

a) A device that shows output on a monitor   

b) A group of connected computers and devices that share resources and communicate   

c) Software for creating documents and presentations   

d) The outer casing that protects internal computer parts   

Answer: b) A group of connected computers and devices that share resources and communicate   

Explanation: A computer network consists of multiple interconnected devices, such as computers, servers, and peripherals, which communicate and share resources like files, printers, or internet connections. This allows users to share data, collaborate, and access common resources more efficiently. 

2. How can the internet be best described?   

a) A collection of connected local area networks (LANs)   

b) A random collection of computers   

c) A network of connected wide area networks (WANs)   

d) A single isolated network   

Answer: a) A collection of connected local area networks (LANs)   

Explanation: The Internet is a global system that connects millions of private, public, academic, business, and government networks of local area networks (LANs) and wide area networks (WANs). It uses standard communication protocols (such as TCP/IP) to link devices worldwide, allowing information exchange across vast distances. 

3. Which of these is an example of Bluetooth technology?   

a) A wide area network (WAN)   

b) A virtual private network (VPN)   

c) A local area network (LAN)   

d) A personal area network (PAN)   

Answer: d) A personal area network (PAN)   

Explanation: Bluetooth is a wireless technology standard designed for exchanging data over short distances, typically between personal devices like smartphones, headphones, and computers. This forms a Personal Area Network (PAN), which has a limited range (usually within 10 meters) and is used for short-range communication. 

4. Which network type is built on top of another existing network?   

a) Overlay network   

b) Prime network   

c) Prior network   

d) Chief network   

Answer: a) Overlay network   

Explanation: An overlay network is built on top of another network. It uses the infrastructure of an existing network (like the internet) to establish a virtual network that can provide additional features such as increased scalability, routing efficiency, or new forms of communication like peer-to-peer (P2P) networks or virtual private networks (VPNs). 

5. What does OSI stand for in networking?   

a) Optical Service Implementation   

b) Open Service Internet   

c) Open System Interconnection   

d) Operating System Interface   

Answer: c) Open System Interconnection   

Explanation: The OSI model (Open Systems Interconnection) is a conceptual framework used to understand and implement standardized communication between computer systems. It divides the process of network communication into seven distinct layers, each with specific functions, ranging from physical hardware to software applications. 

6. When multiple computers function together as one system to clients, what is this called?   

a) Mail system   

b) Networking system   

c) Computer network   

d) Distributed system   

Answer: d) Distributed system   

Explanation: A distributed system is a collection of independent computers that work together as a single system for users. This system allows multiple machines to cooperate and share resources, providing better performance, fault tolerance, and scalability, making it appear as a single coherent system to clients. 

7. How many layers does the ISO OSI reference model contain?   

a) 7   

b) 5   

c) 4   

d) 6   

Answer: a) 7   

Explanation: The OSI reference model is divided into seven layers: Physical, Data Link, Network, Transport, Session, Presentation, and Application. Each layer has a specific role in the process of transmitting data across a network, from physical signaling to end-user application interactions. 

8. In the context of a computer network, what are nodes?   

a) The computer responsible for routing data   

b) The computer where data is terminated   

c) The computer that initiates data transmission   

d) All of the above   

Answer: d) All of the above   

Explanation: A node refers to any device connected to a computer network, which can originate, route, or terminate data communication. Nodes include devices such as computers, routers, switches, servers, or any machine capable of receiving or transmitting data. 

9. Which of the following is NOT a responsibility of the network layer?   

a) Congestion control   

b) Error control   

c) Routing   

d) Inter-networking   

Answer: b) Error control   

Explanation: The network layer is responsible for routing, forwarding, and inter-networking, which involves moving data across multiple networks. Error control is generally handled at the Data Link and Transport layers, where mechanisms like checksums and acknowledgments ensure data is transferred correctly. 

10. What technique is used to allow multiple signals to share the same communication channel in a network?   

a) Multiplexing   

b) Phase modulation   

c) Analog modulation   

d) Digital modulation   

Answer: a) Multiplexing   

Explanation: Multiplexing is a method used in communication networks to combine multiple signals for transmission over a single communication channel or medium. This process maximizes the efficiency of data transmission, allowing multiple streams to coexist and reducing the need for additional channels. 

Computer Network MCQs - Medium Difficulty

Now the questions will be tougher and students need to carefully choose for correct answer. These are some of the advanced questions that include questions related to the in-depth working of computer networks.

11. Which device forwards data packets between networks by using routing information in the packet?   

a) Firewall   

b) Bridge   

c) Hub   

d) Router   

Answer: d) Router   

Explanation: A router is a network device responsible for forwarding data packets between different networks. It uses the destination IP address within the packet to determine the best path for forwarding the data across interconnected networks. 

12. What term is used for an endpoint in an inter-process communication across a network?   

a) Port   

b) Machine   

c) Socket   

d) Pipe   

Answer: c) Socket   

Explanation: A socket is an endpoint in a networked communication flow between two machines or processes. It is associated with a particular IP address and port number, allowing network applications to establish and maintain connections for data exchange. 

13. How do two devices become part of a network?   

a) When the process IDs (PIDs) of processes on both devices match   

b) When a process on one device can exchange information with a process on another device   

c) When one process is active and another is inactive   

d) When processes are running on both devices simultaneously   

Answer: b) When a process on one device can exchange information with a process on another device   

Explanation: Two devices are considered part of a network when they can communicate and exchange information. This is facilitated through the use of communication protocols that allow processes on different devices to connect and share data, such as using IP addresses and port numbers. 

14. From which layer does the data link layer collect packets and encapsulate them into frames for transmission?   

a) Transport layer   

b) Application layer   

c) Network layer   

d) Physical layer   

Answer: c) Network layer   

Explanation: The data link layer is responsible for encapsulating packets from the network layer into frames for transmission across the physical medium. It ensures error detection and manages access to the shared communication medium, preparing the data for transmission. 

15. Which of the following is NOT a network edge device?   

a) Switch   

b) PC   

c) Smartphone   

d) Server   

Answer: a) Switch   

Explanation: A switch is a network device used to connect multiple devices within a LAN, facilitating communication between them. PCs, smartphones, and servers are examples of edge devices, which connect to the network and directly interact with the end-users. 

16. In which type of network is the communication channel shared by all machines?   

a) Anycast network   

b) Multicast network   

c) Unicast network   

d) Broadcast network   

Answer: d) Broadcast network   

Explanation: A broadcast network is a type of network in which all devices share a single communication channel, and messages sent by one device are received by all other devices. Broadcast networks are common in Ethernet-based local area networks (LANs). 

17. Which network topology requires a multipoint connection?   

a) Ring   

b) Bus   

c) Star   

d) Mesh   

Answer: b) Bus   

Explanation: In a bus topology, all devices share a single communication line or cable. Each device is connected to the same bus, which allows for multipoint communication, where data transmitted by one device can be received by all others on the network. 

18. Which system manages the Domain Name System (DNS)?   

a) A single server   

b) A single computer   

c) A distributed database system   

d) None of the above   

Answer: c) A distributed database system   

Explanation: The Domain Name System (DNS) is a distributed database system that translates domain names (e.g., www.example.com) into IP addresses. DNS servers are spread globally and work together to provide name resolution services, ensuring that users can access websites by entering domain names instead of numerical IP addresses. 

19. In the context of IDS/IPS, what is meant by a "signature"?   

a) Normal or baseline network behavior   

b) A file used to define and identify network attacks   

c) An electronic signature for user authentication   

d) An authorization file for network users   

Answer: b) A file used to define and identify network attacks   

Explanation: In Intrusion Detection Systems (IDS) and Intrusion Prevention Systems (IPS), a signature is a set of rules or patterns that help identify known malicious activities or attacks on a network. The system compares network traffic with predefined signatures to detect potential threats. 

20. What does a "router" primarily do in a computer network?   

a) Routes data packets between different networks   

b) Filters network traffic for security   

c) Connects computers within a local network   

d) Converts analog signals to digital signals   

Answer: a) Routes data packets between different networks   

Explanation: A router's primary function is to direct data packets between different networks by analyzing the destination IP address and determining the most efficient route for the packet to reach its destination. This ensures that data travels across multiple interconnected networks to reach its final target. 

Difficult Computer Network MCQs

These are the most advanced and difficult MCQs on computer networks. A person with a clear understanding of networking devices and working can answer these questions.

21. Which term is used for breaking down network congestion in the network layer?   

a) Flow control   

b) Traffic management   

c) Routing control   

d) Load balancing   

Answer: a) Flow control   

Explanation: Flow control is a technique used to manage the rate of data transmission between sender and receiver, preventing congestion. It ensures that a sender does not overwhelm a network or a receiver with too much data at once, allowing the network to operate smoothly without packet loss or delays. 

22. What kind of signal modulation is used in optical fiber communication?   

a) Analog modulation   

b) Digital modulation   

c) Phase modulation   

d) Pulse-code modulation   

Answer: d) Pulse-code modulation   

Explanation: Optical fiber communication primarily uses pulse-code modulation (PCM), which is a method used to digitally represent analog signals. It converts analog signals into a digital bitstream for transmission, offering high-quality signal transmission with low error rates in fiber optic networks. 

23. What is the primary role of a network hub in a network?   

a) To filter data   

b) To forward data to all connected devices   

c) To route data between different networks   

d) To serve as a firewall for security   

Answer: b) To forward data to all connected devices   

Explanation: A network hub is a basic networking device that broadcasts incoming data to all devices connected to it. Unlike a switch or router, a hub does not filter or manage data traffic. It simply forwards incoming packets to all devices, regardless of their destination, which can lead to network inefficiency and congestion. 

24. Which network topology has all devices connected to a single central hub?   

a) Bus topology   

b) Ring topology   

c) Star topology   

d) Mesh topology   

Answer: c) Star topology   

Explanation: In a star topology, all devices (or nodes) are connected to a single central hub or switch. The hub acts as the central point of communication, directing data between devices. This topology is commonly used in local area networks (LANs) and offers easy troubleshooting since each device has a direct connection to the hub. 

25. What is the function of a firewall in a computer network?   

a) To protect the network from unauthorized access   

b) To route data packets to their destination   

c) To forward data across different networks   

d) To monitor the network for performance issues   

Answer: a) To protect the network from unauthorized access   

Explanation: A firewall is a security device that monitors and controls incoming and outgoing network traffic based on predetermined security rules. It serves as a barrier between an internal network and external networks (such as the internet), preventing unauthorized access and protecting against various security threats. 

26. In which type of network topology are all devices connected in a circular chain?   

a) Star topology   

b) Bus topology   

c) Ring topology   

d) Mesh topology   

Answer: c) Ring topology   

Explanation: In a ring topology, devices are connected in a circular loop, where each device has exactly two neighbors. Data travels in one or both directions around the ring until it reaches its intended destination. This topology can offer efficient communication but may suffer from a single point of failure if any device or connection fails. 

27. What does VPN stand for in networking?   

a) Virtual Private Network   

b) Virtual Processing Network   

c) Variable Protocol Network   

d) Vast Processing Network   

Answer: a) Virtual Private Network   

Explanation: A Virtual Private Network (VPN) creates a secure, encrypted connection over a public network, such as the Internet, allowing users to access a private network remotely. It ensures privacy and security by encrypting data transmitted between the user's device and the VPN server, preventing eavesdropping and unauthorized access. 

28. What is the primary function of the transport layer in the OSI model?   

a) Data encapsulation   

b) Error detection and correction   

c) Establishing, maintaining, and terminating connections   

d) Formatting data for transmission   

Answer: c) Establishing, maintaining, and terminating connections   

Explanation: The transport layer (Layer 4 of the OSI model) is responsible for ensuring reliable communication between two devices over a network. It manages connections, flow control, and error recovery. Protocols such as TCP and UDP operate at this layer, providing mechanisms for reliable data transfer. 

29. Which protocol is used to send email messages?   

a) HTTP   

b) FTP   

c) SMTP   

d) SNMP   

Answer: c) SMTP   

Explanation: The Simple Mail Transfer Protocol (SMTP) is used for sending emails from a client to a server or between servers. It handles the process of relaying, sending, and receiving email messages across the internet. 

30. What is the main purpose of a Domain Name System (DNS) server?   

a) To allocate IP addresses dynamically   

b) To convert domain names into IP addresses   

c) To route traffic within a LAN   

d) To manage firewall settings   

Answer: b) To convert domain names into IP addresses   

Explanation: A DNS server resolves human-readable domain names (such as www.example.com) into machine-readable IP addresses. This enables users to access websites using easy-to-remember domain names instead of numerical IP addresses. 

Why Computer Networks MCQ?

Here are some reasons, you should practice with our practice MCQs on Computer Networks:

● Reinforces Theoretical Knowledge: Practicing MCQs helps solidify understanding of key networking concepts and protocols.

● Prepares for Certifications: Essential for preparing for IT certifications such as CCNA, CompTIA Network+, and CCNP.

● Enhances Problem-Solving Skills: Engaging with MCQs improves critical thinking and problem-solving abilities in real-world scenarios.

● Identifies Knowledge Gaps: Helps pinpoint areas where further study is needed, allowing for targeted learning.

● Simulates Exam Conditions: Familiarizes candidates with the exam format, boosting confidence and readiness.

● Addresses Industry Demand: With a projected 3.5 million unfilled cybersecurity positions by 2025, mastering networking is increasingly important for career opportunities.

● Builds Career Readiness: Regular practice equips individuals with the skills necessary to excel in networking and cybersecurity roles.