Network Engineer Interview Questions: A Recruiter’s Guide

Network engineers are crucial for designing, managing and implementing an organization ‘s computer networks. As of early 2024, nearly 1.4 million kilometers of submarine cables are in service globally, connecting us to the internet. This highlights network engineers ‘ importance in ensuring network systems ‘ operation and security. 

This article provides recruiters and hiring managers with top network engineering interview questions that will help assess candidates ‘ technical knowledge, problem-solving skills, experience and fit for network engineering roles. 

Methodology: Using the Situation, Task, Action, Result Format

The situation, task, action, result method for framing interview questions is a technique that allows candidates to describe real-life situations and enables interviewers to evaluate how a candidate handled a specific problem and what strengths and skills they demonstrated to achieve the desired results. Here ‘s an example of a question based on the STAR format: Describe a time when you had to troubleshoot a complex network issue. 

The following is a list of common network engineer interview questions for recruiters to ask.

1. Can You Explain the OSI Model and Its Layers?

The Open Systems Interconnection model was the first network communications model; it was adopted in the 1980s. It describes seven layers that computer systems use to communicate over a network, which include:

• The physical layer that transmits over a physical medium
• The data link layer that defines the data format on the network
• The network layer that outlines the physical path for the data
• The transport layer that transmits data using TCP and UDP transmission protocols
• The session layer that controls the ports and sessions over the network
• The presentation layer that encrypts data and transforms it into a usable format 
• The application layer that allows human-computer interaction to access network services 

Why You Should Ask This Question

It helps you assess a candidate ‘s knowledge of the OSI model ‘s fundamental nature, as well as their grasp of network architecture and protocols and practical application. 

What to Expect from the Candidate

The candidate should name the seven layers in their correct order, demonstrate knowledge of each layer ‘s function and provide examples of technologies and protocols for each layer. 

2. How Would You Troubleshoot a Slow Network Connection?

This question will allow you to determine whether the candidate can identify the scope of a problem, check physical connections and hardware to diagnose the problem ‘s source, use network monitoring tools and network logs, perform bandwidth tests, check for malware and unauthorized access and review network configurations. 

Why You Should Ask This Question

It helps to evaluate a candidate ‘s troubleshooting skills, problem-solving ability and familiarity with diagnostic tools and techniques. 

What to Expect from the Candidate

The candidate should describe a systematic approach to troubleshooting and demonstrate their knowledge of specific diagnostic tools and ability to examine hardware and software issues. 

3. Describe Your Experience with Network Security Protocols and Best Practices.

This allows recruiters to determine a candidate ‘s familiarity with common protocols such as SSL/TLS, IPsec, SSH, HTTPS and best practices related to firewalls, security audits, network segmentation, password management, updates, training and defense and encryption concepts. 

Why You Should Ask This Question

It ‘ll help you assess the candidate ‘s knowledge of network security protocols and practices and their experience in implementing and maintaining secure networks. 

What to Expect from the Candidate

They should explain network security protocols and their applications and demonstrate their knowledge of best practices in network security, as well as security measures implementation and specific security tools or software. 

4. How Do You Approach Capacity Planning for a Growing Network?

A qualified and experienced network engineer would understand the concept of network capacity planning and be familiar with the tools or techniques used in the process. They should be able to assess network usage and performance, identify growth trends, forecast future requirements, identify potential bottlenecks, plan for scalability and understand and recommend new technologies. 

Why You Should Ask This Question

It demonstrates the candidate ‘s network capacity planning skills and assesses their ability to think strategically about network infrastructure, resource management and long-term goals. 

What to Expect from the Candidate

The candidate should outline a systematic approach to capacity planning, demonstrate knowledge of tools for forecasting network growth and understand the importance of balancing costs with performance requirements. 

5. Can You Explain the Difference Between TCP and UDP?

A network engineer should know the differences between data transfer protocols such as TCP and UDP and should understand network connection types, data delivery methodology and speed and performance measures. 

Why You Should Ask This Question

This question will determine if the candidate has an in-depth understanding of TCP and UDP, which is fundamental to network engineering.

What to Expect from the Candidate

They should clearly explain TCP and UDP ‘s key differences, demonstrate an understanding of the advantages and disadvantages of each protocol, provide examples of applications using TCP or UDP and discuss scenarios where one protocol is better than the other.

6. How Do You Stay Updated with the Latest Networking Technologies and Trends?

This allows candidates to discuss which methods they use to stay updated in the networking field. This should ideally include continuous education and certifications, regular review of industry publications and blogs, participation in conferences, workshops, online forums and communities, active engagement with thought leaders on social media and experimenting with new technologies. 

Why You Should Ask This Question

It highlights the candidate ‘s interest in continuing to learn about the networking field, their commitment to professional development and their proactivity in learning and adapting to new technologies. 

What to Expect from the Candidate

The candidate should outline the methods they use to stay updated, their awareness of current trends and emerging technologies, the specific resources they use, the communities they follow, the publications they regularly review and the approach they use to learn and self-improve. 

7. Describe a Complex Network Issue You ‘ve Resolved. What Was Your Approach?

Here is a perfect example of the STAR format; it pushes the candidate to outline specific steps to identify and define a problem, analyze and diagnose it and develop and implement a solution for resolving a complex network issue. 

Why You Should Ask This Question

It assists you in assessing the candidate ‘s problem-solving skills in real-world scenarios and demonstrates their technical expertise and ability to handle complex issues. 

These top network engineer interview questions allow recruiters to:

• Screen qualified network engineers
• Efficiently identify the ones to pursue
• Evaluate the candidates ‘ technical and soft skill

For additional support in securing top talent in the network engineering field, please contact our team today.