Get discounts on data, AI, and programming courses. View offers

Maya Maceka | 11 Aug, 2023

Top 48 Networking Interview Questions and Answers in 2024

If you want to land a network engineer role, you need compelling responses to networking interview questions. These challenges often make or break an opportunity. The best network interview question responses help jobseekers make strong impressions and land lucrative jobs. After all, with network engineers earning average median salaries upwards of $120k, there’s never been a better time to enter the field.

To give yourself the best shot at landing the job, it’s wise to highlight your technical skills with correct answers to common networking interview questions. That’s why we’ve put together this helpful guide. It covers the top 48 computer networking interview questions asked in technical interviews.

Whether you’re interviewing for a beginner, intermediate, or advanced position, this guide will serve as a valuable resource to help you boost your knowledge and ace your interview. Let’s get started!

Basic Networking Interview Questions and Answers

1. What Is a Network?

A network is a group of connected devices that share information or resources. These devices communicate with each other over the network, which can be wired or wireless, and can vary in size from a small home network to a large global one, like the Internet.

Of all networking basic interview questions, this is one you should be able to answer automatically!

Find Remote Networking Jobs

2. How Are Network Types Classified? Explain the Difference.

Network types are characterized based on their size, geographical dispersion, and how devices connect. The fundamental distinction between these network types is their geographical range and the devices they link. 

Type

Description

LAN (Local Area Network)

Connects devices within a small area, such as a single building or office.

WAN (Wide Area Network)

Connects devices over a large geographical area, such as across cities or even countries.

MAN (Metropolitan Area Network)

Connects devices within a city or metropolitan area.

PAN (Personal Area Network)

Connects devices that are close to an individual, such as a smartphone or personal computer.

GAN (Global Area Network)

Connects mobile devices across multiple countries, continents, or even across the entire globe.

WLAN (Wireless Local Area Network)

Type of LAN that uses wireless communication instead of physical cables to connect devices.

VLAN (Virtual Local Area Network)

A virtual network that is created within a physical LAN. It allows you to divide a single physical LAN into multiple logical LANs, each with its broadcast domain.

This is another one of the most basic networking questions, so make you know these!

3. What Is a Data Packet?

A data packet is a unit of data that is transferred over a network. It includes data and control information, including the source, destination addresses, and error-checking information.

When you send an email, your computer breaks it down into data packets to send it over the network. On the receiving end, the packets are reassembled into the original message. Data packets enable us to send data efficiently over long distances. 

4. What Are Routers?

Routers are devices that connect various networks and help the devices on those networks communicate with each other. This is done by routing data packets between networks based on destination addresses.

5. What’s the Difference Between Hub, Switch, Router, and Gateway?

In a computer network, Hubs, Switches, Routers, and Gateways are all networking devices that serve different purposes. Here's a brief explanation of each.

Device

Description

Hub

A basic networking device that links several devices in a network by broadcasting data from one device to all other devices connected to it.

Switch

A higher-level networking device that links numerous devices in a network and, unlike a hub, employs hardware addresses to transmit data solely to the desired device rather than broadcasting to all devices. 

Router

A networking device that links various networks and directs data packets according to their destination addresses. Routing tables, which indicate the optimal path for data to travel to reach its destination, are used by routers to make judgments on how to transmit data. 

Gateway

A device that serves as the entry point to a different network or as an interface between two different networks. A gateway can be a router, but it can also be a computer or another type of device that provides the necessary functions to connect two different networks. 

In summary, hubs broadcast data to all connected devices, switches forward data based on the hardware address, routers forward data depending on the destination address, and gateways provide entry to another network or perform functions such as protocol translation. These are common interview questions for network technicians, so make sure you know the differences.

6. What Is a VPN?

A VPN (Virtual Private Network) is a secure network connection between a device and a network. It does this by encrypting data, making them useful for online privacy, securing connections, and accessing geo-restricted resources. There are several types of VPNs.

Type

Description

Remote Access VPN

Enables remote users to securely access a company's network.

Site-to-Site VPN

Connects multiple fixed locations over a public network.

Intranet-based VPN

Used to securely connect to a company’s intranet.

Extranet-based VPN

Connects a company to its partners or suppliers.

Consumer VPN

Designed for individuals to protect their online privacy and security.

Dedicated VPN

A private network set up for a single organization.

Mobile VPN

Designed for mobile devices to provide secure access to a network.

Nodes are network-connected devices like computers, routers, and servers, while links are the connections between nodes that allow them to communicate. This means that nodes are the endpoints of communication and links are the channels that enable communication.

This is another of those networking basics interview questions that you should be able to answer without blinking!

8. What Is the Purpose of a Firewall in a Network?

A firewall controls incoming and outgoing network traffic to protect a network from unwanted access. Serving as the initial line of protection, they monitor and filter traffic based on security rules. Firewalls can be either hardware or software-based.

9. What Is the Difference Between HTTP and HTTPS? What Ports Do They Use?

HTTP (Hypertext Transfer Protocol) and HTTPS (Hypertext Transfer Protocol Secure) are two very common data transmission technologies that provide comparable functions, but differ in security and port use.

Type

Description

HTTP

A stateless, application-level protocol for online data transmission. It is the basic protocol utilized by the World Wide Web and is used to convey data between a client and a server. By default, HTTP communicates on port 80.

HTTPS

A variation of an HTTP that enables encrypted and secure communication between a client and a server using TLS (Transport Layer Security) or SSL (Secure Sockets Layer). HTTPS communicates on port 443.

10. What Are the Different Types of IP Addresses?

There are four types of IP addresses used in networking: public IP addresses, private IP addresses, static IP addresses, and dynamic IP addresses. They differ in their function and behavior.

Type

Description

Public IP address

Assigned to Internet-connected devices. They are unique and globally identifiable, allowing devices to communicate with each other over the Internet.

Private IP address

Used within a private network and are not intended to be accessible over the Internet. They are allocated to devices like computers, printers, and routers in local area networks (LANs). 

Static IP address

Allocated to a device that does not change over time. This sort of IP address is beneficial for devices that require a stable IP address, such as servers or websites.

Dynamic IP address

Temporary address issued to a device that does not need a constant IP address, such as PCs and smartphones.

Reserved IP address

An address reserved for special purposes, such as 127.0.0.1 for the localhost.

This is another of our basic network interview questions that you need to know!

11. What Is Ethernet?

Ethernet is a collection of wired networking technologies used for transmitting data between devices and is the de facto standard for local area networks (LANs).

Ethernet networks utilize a physical and data link layer to transmit data between devices.The physical layer defines the electrical and mechanical specs for data transmission over the cable, and the data link layer defines how data is packaged and transmitted between devices.

12. What Is the Difference Between an Encoder and a Decoder?

An encoder converts information to a new format, while a decoder reverses the process to retrieve the original data. Both use algorithms and techniques for data compression and security. 

13. What Is Localhost?

Localhost refers to the computer you're currently using. You can connect to it using the IP address 127.0.0.1, which is reserved for the "loopback" interface that allows a computer to communicate and send data to itself. Connecting to localhost is helpful for testing and development, including testing whether a web server is functional.

14. What Are the Different Types of Data Transferring Modes?

Mode

Description

Example

Simplex 

Data flow in unidirectional

TV broadcast

Half-duplex

Data flows in both directions (transmit & receive), but not at the same time.

Walkie-talkie, citizens band radio

Full-duplex

Data can flow in both directions (transmit & receive) at the same time.

Telephone, internet browsing, video conferencing

15. Describe the Steps to Troubleshoot a Network Connectivity Issue?

Step One

Identify the symptoms of the issue and then check if the problem is with the specific device, or if it’s network-wide.

Step Two

Check all cables, power supplies, and network devices for physical connectivity.

Step Three

Check the IP and DNS configurations to ensure they are correct.

Step Four

Check if any firewalls are blocking the connection.

Step Five

Use diagnostic tools such as traceroute, nslookup, and netstat.

Step Six

If the issue persists, gather data, including network logs and traces.

Step Seven

Work with the network administrator or service provider to resolve the issue.

Want to go the extra mile to prepare for your interview? Check out:

The Top Technical Interview Questions

Intermediate Networking Interview Questions and Answers

16. What Is the Difference Between Ipconfig and Ifconfig?

They are command-line tools used to view and configure network settings, including changes to the DHCP and DNS settings. 

Feature

ipconfig

ifconfig

Definition

Internet Protocol Configuration

Interface Configuration

Platform

Windows

Linux/Unix

Displays

IP address, subnet mask, default gateway

IP address, network interface details

17. What Is the Purpose of the Ping Command?

Ping is a diagnostic tool to test network connectivity that sends an ICMP echo request to a target device and waits for a response.

The purpose of pinging is to verify that a network device is responsive and to measure the time it takes for data packets to travel to/from the source. Pinging can help identify network issues (like packet loss) and is often used in troubleshooting. 

18. What Is the OSI Reference Model? Describe the Layers.

The Open Systems Interconnection (OSI) reference model is a seven-layer architecture that specifies how data is conveyed across a network. The OSI model provides a standardized approach to network communication that enables devices to coexist. The layers are as follows: 

Layer

Description

Physical

Deals with the physical aspects of data transmission, such as voltage levels, cable specifications, and signal timing.

Data Link

Delivers data frames between devices on a particular network segment. This includes error detection and correction, flow control, and media access.

Network

Routes data from one network using the most optimal route, determined by IP addresses. 

Transport

Provides end-to-end transmission services and ensures reliable data delivery. 

Session

Creates, manages, and ends sessions between applications. It guarantees that data is transmitted in proper order. 

Presentation

Formats, encrypts, and compresses data for transmission. 

Application

Serves as the interface between the user and the network and provides services like file transfer, email, and remote logins. 

19. What Is the TCP/IP Model? Describe the Layers. 

The TCP/IP (Transmission Control Protocol/Internet Protocol) reference model uses a four-layer architecture to provide a standard for online data transmission. The layers are as follows: 

Layer

Description

Application

Delivers services directly to the host’s apps. It covers protocols needed to transport data, such as HTTP, FTP, and SMTP. 

Transport

Provides dependable data transmission services between apps using TCP and UDP (User Datagram Protocol). 

Internet

Handles the routing and forwarding of data packets throughout the network using IP. 

Network Access

Offers data connection services between network devices like switches and routers using Address Resolution Protocol (ARP) and Internet Control Message Protocol (ICMP). 

20. What Is the MAC Address and How Is It Different From the IP Address?

A MAC (Media Access Control) address is a physical address in the form of a unique 48 bit identifier for a NIC (Network Interface Card) that is used for network communication inside a network segment. An example of a MAC address is 00:1A:2B:3C:4D:5E. 

An IP address is a logical identifier to find a device on the internet or on a network. They are assigned by a network administrator and can change. An example of an IP address is 192.0.2.1.

21. What Is a Subnet and How Is a Subnet Mask Used to Divide a Network Into Smaller Subnets?

A subnet is a logical sub-section of a larger network to improve organization, security, and performance. A subnet mask is a 32-bit value that is combined with an IP address to divide a network into smaller sections, known as subnets.

For example, the IP address 192.168.1.1 with a subnet mask of 255.255.128.0 would have a subnet range of 192.168.0.1 - 192.168.127.254. With the subnet mask you can identify the part of an IP address that refers to the network address and the part for the host.

22. What Is a Proxy Server?

A proxy server is a server that acts as an intermediary between clients and servers. It provides access control, security, caching, and anonymity for clients and can be used to improve the performance and security of a network.

23. What Is Network Topology? Describe the Different Types. 

A network topology refers to how devices in a network are linked to one another and how data is carried between those devices. The types of network topologies are as follows:

Topology

Description

Bus

Devices are linked together by a single central connection known as a bus, which serves as a shared communication channel.

Star

Devices are connected to a central hub, with each device having a dedicated point-to-point connection to the hub.

Ring

Devices are connected in a circular pattern, with data traveling through each device and returning to the source.

Mesh

Each device in the network has a direct link to every other device, allowing data to move via various pathways.

Tree

A hierarchical topology in which devices are grouped in a tree-like arrangement, with a central root device and child device branches.

Hybird

Uses two or more differing network topologies, and can include a mix of the others liste above.

This is one of the most essential network architecture interview questions, so pay attention!

24. What Is an IPv4 Address and the Different Classes of IPv4?

An IPv4 address is a unique numerical value that’s assigned to every internet-connected device. These are divided into different classes based on their value range to help organize the Internet. 

Class

Range of First Octet

Number of Networks

Number of Hosts Per Network

A

1 to 127

126

16,777,214 (large organizations and ISPs)

B

128 to 191

16,382

65,534 (medium-sized organizations)

C

192 to 223

2,097,150

254 (small organizations and home networks)

D

224 to 239

N/A

Multicasting

E

240 to 255

N/A

Research/experimental use

25. What Is a DMZ and Why Is It Used in Networking?

A Demilitarized Zone (DMZ) is a secured network area used for public-facing services, acting as a buffer between the internet and internal network to increase security and protect sensitive data. It’s used in networking as a way to isolate potential threats and keep data safe. 

26. What Is a DNS?

DNS (Domain Name System) is used to translate human-readable domains like hackr.io into an IP address, allowing computers to identify and communicate with each other over the internet.

27. What Is BGP and How Does It Work in a Network?

The Border Gateway Protocol (BGP) is a routing protocol that allows routers to communicate and find the best way to route traffic. It creates routing tables to optimize traffic flow and ensures efficient data packet delivery. BGP is crucial for large networks to prevent congestion and rerouting traffic if necessary. 

Advanced Network Interview Questions and Answers

28. What Are CIDR Blocks?

Classless Inter-Domain Routing (CIDR) is a method of allocating IP addresses and defining network boundaries. CIDR blocks are defined via the combination of an IP address and a subnet mask, enabling the specification of which addresses are included in the block.

For example, the CIDR block 192.168.0.0/24 would include all IP addresses from 192.168.0.0 to 192.168.0.255, with the subnet mask being 255.255.255.0.

CIDR blocks are commonly used by ISPs to allocate IP addresses to customers and by organizations to define their network boundaries and to efficiently manage their IP address space.

29. What Is the Difference Between TCP and UDP Protocols?

TCP (Transmission Control Protocol) and UDP (User Datagram Protocol) are both protocols for sending send data over the Internet, with the primary difference being the way they transmit data.

Feature

TCP

UDP

Type

Connection-oriented

Connectionless

Reliability

High - ensures all packets are received and in order

Low - packets may be lost or delivered out of order

Speed

Slower due to establishing and maintaining connections

Faster due to no overhead of connection establishment

Packets

Ordered

Unordered

Error checking

Yes - includes error checking and retransmission of lost packets

Limited - includes basic error checking but does not retransmit lost packets

Usage

Suitable for applications where data accuracy and reliability are important, such as web browsing and file transfer

Suitable for applications where speed is important, such as online gaming and streaming media

This is one of the most popular computer networks interview questions, so be sure to know this!

30. What Is the DHCP Protocol?

DHCP (Dynamic Host Configuration Protocol) is a network protocol that automatically assigns IP addresses to networked devices. This happens when a device connects to a network, as it sends an IP address request, which the DHCP server responds to.

31. What Is the ARP Protocol and How Does It Map an IP Address to a Physical Address in a Network?

ARP (Address Resolution Protocol) is a networking protocol that maps IP addresses to physical MAC addresses. A device first checks its ARP cache for the physical address, and if not found, broadcasts an ARP request to all network devices to obtain it. The device with the matching IP address responds with the physical address, which is then saved in the ARP cache.

32. What Is the FTP Protocol?

FTP (File Transfer Protocol) is a network protocol that’s used to transfer files between devices over the Internet via a client-server model. And while it’s being replaced by more secure protocols like SFTP and SCP, it’s still widely used.

Don’t overlook these types of computer network interview questions, as they’re an easy win!

33. What Is the SNMP Protocol and Describe Its Architecture?

SNMP (Simple Network Management Protocol) monitors and manages network devices via a client-server architecture. With this, NMS (Network Management Systems) can request information about device performance and configuration.

It also uses MIB (Management Information Base) objects to represent device performance, allowing network managers to monitor their networks.

34. What Are Unicasting, Anycasting, Multicasting, and Broadcasting?

These are all methods of transmitting data in computer networks but differ depending on the specific requirements and nature of the data transmission.

Type

Description

Unicasting

The delivery of data from a single source to a single network device. It’s a one-on-one communication model.

Anycasting

The delivery of data from a single source to the nearest possible destination based on routing table information. It’s a one-to-nearest communication model.

Multicasting

The delivery of data from a single source to several destinations on a network. It’s a one-to-many communication model.

Broadcasting

The delivery of data from a single source to all possible destinations on a network. It’s a one-to-all communication model. 

35. What Is Quality of Service (QoS) And How Is It Used to Manage Network Traffic?

Quality of Service (QoS) is used to regulate network traffic by prioritizing traffic types and allocating bandwidth efficiently, improving network performance and user experience.

It can be used to avoid congestion by prioritizing crucial traffic over lower-priority as per the network’s requirements. For instance, this may mean giving priority to audio and video over email and file transfers.

36. How Does IPv6 Address Space Differ From IPv4?

Feature

IPv6

IPv4

Address Length

128 bits

32 bits

Address Format

Hexadecimal

Dotted Decimal

Address Space

2^128

2^32

Header

Fixed length

Variable length

Address Masks

No

Yes

QoS

Yes

No

DNS Record

AAAA

A

Example Address

2001:0db8:85a3:0000:0000:8a2e:0370:7334

192.0.2.1

37. What Is MPLS and How Is It Used in a Network?

MPLS (Multiprotocol Label Switching) uses short labels instead of lengthy network addresses to route network traffic, and it’s often used to provide QoS and VPNs. 

38. What Is the Relationship Between a NIC and NAT, and How Do They Work Together to Enable Network Communication?

A NIC (network interface card) is a hardware device that enables a computer to connect to a network, whereas NAT (Network Address Translation) is a protocol used to translate private IP addresses to public IP addresses, allowing communication over the internet. 

When a computer with a NIC sends a request to an online server, the NAT protocol is used to translate the IP address, enabling the communication to take place. These are often used together to troubleshoot network connectivity issues. 

Interested in a career in network engineering? Check out:

The Top Network Engineering Questions

Networking Interview Multiple Choice Questions

39. What Is the Main Function of a Router in a Network?

  1. To provide network security
  2. To connect multiple networks 
  3. To manage data storage
  4. To control network access

40. What Protocol Is Used for File Transfers Over a Network?

  1. FTP
  2. HTTP
  3. SMTP
  4. TCP

41. What Is the Most Commonly Used IP Address Range for Private Networks?

  1. 192.0.0.0 - 192.255.255.255
  2. 10.0.0.0 - 10.255.255.255
  3. 127.0.0.0 - 127.0.0.1
  4. 169.254.0.0 - 169.254.255.255

42. What Is the Purpose of a Firewall in a Network?

  1. To filter incoming and outgoing network traffic
  2. To provide network security
  3. To manage network access
  4. All of the above

43. What Is the Difference Between TCP and UDP Protocols?

  1. TCP is connection-oriented, UDP is connectionless
  2. TCP is unreliable, UDP is reliable
  3. TCP is fast, UDP is slow
  4. TCP is for voice, UDP is for video

44. What Is the Purpose of Subnetting in a Network?

  1. To improve network security
  2. To divide a large network into smaller subnets
  3. To improve network performance
  4. To simplify network management

45. What Is the OSI Model Used for in Networking?

  1. To standardize data transfer between devices
  2. To ensure compatibility between different networking devices
  3. To control access to a network
  4. To manage network resources

46. What Is the Difference Between a Static and a Dynamic IP Address?

  1. A static IP address does not change, a dynamic IP address changes frequently
  2. A static IP address is used for public access, a dynamic IP address is used for private access
  3. A static IP address is assigned by a network administrator, and a dynamic IP address is assigned automatically by a DHCP server
  4. A static IP address is faster, and a dynamic IP address is slower

47. What Is the Role of DNS in a Network?

  1. To assign IP addresses to devices
  2. To provide access to web services
  3. To resolve domain names to IP addresses
  4. To manage network traffic

48. What Is the Purpose of VLANs in a Network?

  1. To isolate network traffic
  2. To simplify network management
  3. To improve network performance
  4. To increase network security.

Bonus Tips for Networking Interviews

  • Use the STAR Method (Situation, Task, Action, and Result) to answer open-ended questions.
  • Prepare for common behavioral questions:
      • Describe a time you had to troubleshoot a complex network issue and explain how you approached the problem?
      • How do you keep up with the latest advancements in networking?
      • How would you communicate technical information to non-technical stakeholders?
  • Highlight your soft skills, especially those related to communication, adaptability, critical thinking, and teamwork.
  • Be honest about your knowledge if you don’t know the answer to a question. Instead, suggest a plan for finding a solution and avoid guessing or saying “I don’t know”. 
  • Show enthusiasm by asking about training and certifications, and mention other features that make you want to work there, like remote working or short commutes.

Conclusion

That concludes our list of 48 networking interview questions and answers that you need to know in 2024, ranging from beginner to advanced. Whether you’re interviewing for an entry-level technician position or a senior role, this guide will help you feel prepared for anything. 

Also remember to prepare for behavior-based questions in addition to the more factual ones, as this shows the interviewer that you’re well-rounded as well as experienced. 

If you have questions about any of the topics mentioned, please leave a comment down below. Thanks for reading and good luck with your interview!

Want to learn about networking? Check out:

The Bits and Bytes of Computer Networking

 

STAY IN LOOP TO BE AT THE TOP

Subscribe to our newsletter

Welcome to the club and Thank you for subscribing!

By Maya Maceka

Maya Maceka is a writer from Canada who is passionate about technology and innovation. She is a specialist in DeFi, including blockchain technology, cryptocurrencies, and NFTs. "Blockchain is going to change the way our world works — it's the future of content."

View all post by the author

Learn More

Please login to leave comments