Top Networking Interview Questions and Answers
- crawsecsaket
- 3 hours ago
- 4 min read
W

hat is a Network?
According to Merriam-Webster, a network is typically defined as an informally interconnected group or association of different entities, such as people, computers, or radio stations.
For instance, Domino’s has a network of over 1,200 branches across India. Similarly, a computer network is a system where computers or peripherals are connected to each other through a common communication channel, enabling the exchange of information and data.
Why are Computer Networks so Important?
Have you ever heard of the Internet—or “the Net”? Of course, you have, as you’re reading this online. But have you ever wondered what the Internet really is? It’s essentially a network of networks, linking devices worldwide and allowing seamless communication and data sharing. This makes computer networking one of the most vital concepts in both our daily lives and technical interviews.
Below is a list of the most commonly asked networking questions in interviews, organised into basic, intermediate, and advanced levels.
Basic Networking Interview Questions
What is an IPv4 address, and what are its classes?
An IPv4 address is a 32-bit address divided into four octets. Its classes (A, B, C, D, E) are based on the first octet and determine network size and purpose.
Explain the different types of networks.
Examples include PAN (Personal Area Network), LAN (Local Area Network), MAN (Metropolitan Area Network), WAN (Wide Area Network), and GAN (Global Area Network).
What is a LAN (Local Area Network)?
A LAN connects devices within a limited area, such as a home or office, allowing resource sharing like printers or files.
What is a VPN (Virtual Private Network)?
A VPN is a secure tunnel built on the Internet, enabling safe connections between networks and remote access to organisational resources.
What are the advantages of using a VPN?
It allows remote office connections, protects confidential data, ensures secure transactions, encrypts traffic, and reduces costs compared to WANs.
Intermediate Networking Interview Questions
What is DNS (Domain Name System)?
DNS translates domain names (e.g., interviewbit.com) into corresponding IP addresses, enabling communication between devices.
What is the difference between a router and a gateway?
A router connects similar networks, while a gateway can connect dissimilar networks and regulate traffic.
What is SMTP?
The Simple Mail Transfer Protocol defines rules for sending emails between servers, usually on port 25.
What is the OSI Reference Model?
The OSI model is a 7-layer architecture standardising how systems communicate across networks.
What is the TCP/IP Reference Model?
A simplified 4-layer model developed by the US DoD, forming the foundation of modern networking.
Advanced Networking Interview Questions
What is FTP?
File Transfer Protocol enables reliable and efficient file sharing between hosts.
What is TCP, and how does it differ from UDP?
TCP is connection-oriented and reliable, whereas UDP is connectionless, faster, but less reliable.
What is ICMP?
Internet Control Message Protocol is used for error handling and diagnostics by devices like routers.
What is DHCP?
Dynamic Host Configuration Protocol automatically assigns IPs and configurations to devices on a network.
What is ARP?
Address Resolution Protocol maps logical IP addresses to physical MAC addresses for communication within local networks.
Conclusion
Computer networks form the backbone of modern communication and technology. From small personal networks to vast global systems like the Internet, networks enable seamless data transfer, resource sharing, and secure connections across the world. Understanding core networking concepts such as IP addressing, DNS, VPNs, and protocols like TCP/IP is essential for both everyday use and technical interviews. As our reliance on digital infrastructure continues to grow, a strong knowledge of networking remains a crucial skill for students, professionals, and organisations alike.
Frequently Asked Questions (FAQs)
1. What is the main purpose of a computer network?
The primary purpose is to allow devices to connect, share resources, and exchange information efficiently.
2. How does a LAN differ from a WAN?
A LAN connects devices within a limited area like a building, while a WAN covers large geographical areas, often linking multiple LANs.
3. What is the difference between TCP and UDP?
TCP is reliable, connection-oriented, and ensures data delivery, whereas UDP is faster, connectionless, and does not guarantee delivery.
4. Why is DNS important in networking?
DNS translates human-readable domain names into IP addresses, making it easier for users to access websites without remembering numerical addresses.
5. What is the role of a router in a network?
A router connects different networks, directing traffic and ensuring data reaches the correct destination.
6. What are private IP addresses used for?
Private IP addresses are reserved for devices within local networks and cannot be used directly on the Internet.
7. How does a VPN improve security?
A VPN creates a secure, encrypted tunnel between devices and networks, protecting data from intrusions and maintaining confidentiality.
8. What is the OSI model, and why is it important?
The OSI model standardises how systems communicate over networks, breaking down communication into seven layers for easier understanding and troubleshooting.
9. What is subnetting, and why is it used?
Subnetting divides a large network into smaller sub-networks, improving routing efficiency, security, and network performance.
10. How does a firewall protect a network? A firewall monitors and controls incoming and outgoing traffic, blocking unauthorised access and protecting networks from cyber threats.
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