Essential Work Sample Exercises for Hiring a Senior Network Engineer

Network infrastructure forms the backbone of modern organizations, making the Senior Network Engineer role critical to operational success. These professionals design, implement, and maintain the complex systems that enable business communication and data transfer. A poor hiring decision in this role can lead to network vulnerabilities, performance issues, and costly downtime that impacts the entire organization.

Traditional interviews often fail to reveal a candidate's true capabilities in network engineering. While candidates may articulate theoretical knowledge well, their practical skills in designing solutions, troubleshooting complex problems, and implementing security measures remain untested. This disconnect can lead to hiring individuals who interview well but struggle with real-world network challenges.

Work sample exercises provide a window into how candidates approach actual network engineering tasks. By observing candidates as they design network architectures, troubleshoot issues, or evaluate security postures, hiring teams gain valuable insights into technical competence, problem-solving methodologies, and communication skills. These exercises reveal not just what candidates know, but how they apply that knowledge.

The following work samples are designed to evaluate the essential skills required for a Senior Network Engineer. Each exercise simulates real-world scenarios that test technical expertise, critical thinking, and the ability to communicate complex concepts clearly. By incorporating these exercises into your hiring process, you'll be better equipped to identify candidates who can truly excel in this crucial role.

Activity #1: Network Architecture Design

This exercise evaluates a candidate's ability to design scalable, resilient network architectures that align with business requirements. Senior Network Engineers must balance performance, security, and cost considerations while planning infrastructure that supports organizational growth. This activity reveals how candidates approach complex design challenges and their familiarity with current networking technologies and best practices.

Directions for the Company:

• Prepare a fictional company scenario with specific business requirements (e.g., multi-site organization with 500+ employees, plans for growth, specific security or compliance needs).
• Provide network diagrams of the "current state" infrastructure with identified limitations or problems.
• Include a budget constraint and timeline to assess the candidate's ability to work within practical limitations.
• Allow 45-60 minutes for the exercise, with an additional 15-20 minutes for presentation and feedback.
• Have a technical interviewer present who can ask probing questions about design choices.

Directions for the Candidate:

• Review the provided company scenario and current network architecture.
• Design a new or improved network architecture that addresses the organization's needs and resolves existing limitations.
• Create a network diagram (using provided diagramming tools or whiteboard) showing the proposed solution.
• Prepare a brief explanation of your design choices, including technology selections, redundancy considerations, and security implementations.
• Be prepared to discuss how your design balances performance, security, and cost considerations.

Feedback Mechanism:

• After the candidate presents their design, provide specific feedback on one strength (e.g., "Your redundancy planning was particularly thorough") and one area for improvement (e.g., "The security zoning could be more granular").
• Ask the candidate to revise a portion of their design based on the improvement feedback, giving them 5-10 minutes to make adjustments.
• Observe how receptive they are to feedback and their ability to incorporate suggestions while defending valid design decisions.

Activity #2: Network Troubleshooting Scenario

This exercise assesses a candidate's methodical approach to diagnosing and resolving complex network issues. Senior Network Engineers must efficiently identify root causes of problems while minimizing disruption to business operations. This activity reveals a candidate's troubleshooting methodology, technical knowledge depth, and ability to work under pressure.

Directions for the Company:

• Create a realistic network troubleshooting scenario with multiple potential causes (e.g., intermittent connectivity issues between specific network segments).
• Prepare a document with system information, relevant logs, and network diagrams that contain clues to the issue.
• Include some red herrings or irrelevant information to test the candidate's ability to focus on pertinent details.
• Provide access to a simulated environment or detailed documentation that allows the candidate to "investigate" the issue.
• Allow 45 minutes for the troubleshooting exercise.

Directions for the Candidate:

• Review the scenario information and available diagnostic data.
• Document your troubleshooting approach, including what you would check first and why.
• Identify potential causes of the issue based on the provided information.
• Recommend specific steps to resolve the problem, including any configuration changes or hardware replacements.
• Explain how you would verify the solution worked and prevent similar issues in the future.
• Prioritize your actions based on business impact and resolution time.

Feedback Mechanism:

• After the candidate presents their findings and solution, provide feedback on their methodology and technical accuracy.
• Highlight one strength in their approach and one area where their troubleshooting could be more efficient or thorough.
• Present a follow-up scenario where the initial solution didn't completely resolve the issue, and give them 10 minutes to adjust their approach.
• Evaluate their adaptability and resilience when their first solution isn't entirely successful.

Activity #3: Network Security Assessment

This exercise evaluates a candidate's ability to identify security vulnerabilities and implement appropriate controls. Senior Network Engineers must protect organizational assets while maintaining network performance and accessibility. This activity reveals the candidate's security mindset, knowledge of current threats, and ability to balance security with usability.

Directions for the Company:

• Prepare a network diagram and configuration snippets for a fictional organization with intentional security vulnerabilities.
• Include a mix of obvious and subtle security issues across different network components (firewalls, switches, wireless, etc.).
• Provide the company's security requirements and compliance obligations.
• Allow 40 minutes for the assessment and 15 minutes for presentation of findings.
• Have a security-focused interviewer present who can discuss the candidate's recommendations.

Directions for the Candidate:

• Review the provided network documentation and identify potential security vulnerabilities.
• Categorize the identified issues by severity and potential business impact.
• Recommend specific remediation steps for each vulnerability, including configuration changes or additional security controls.
• Consider how your recommendations might affect network performance or user experience.
• Prepare a brief presentation of your findings as if you were reporting to IT leadership.
• Include both immediate actions and longer-term security improvements in your recommendations.

Feedback Mechanism:

• After the candidate presents their security assessment, acknowledge the vulnerabilities they correctly identified and note any they missed.
• Provide feedback on one particularly strong recommendation and one recommendation that could be improved or refined.
• Ask the candidate to revise their approach to the improvement area, giving them 5-10 minutes to develop a better solution.
• Evaluate their security knowledge, prioritization skills, and ability to communicate security concepts clearly.

Activity #4: Network Migration Planning

This exercise assesses a candidate's project planning abilities and foresight in managing complex network changes. Senior Network Engineers must plan and execute infrastructure changes with minimal disruption to business operations. This activity reveals the candidate's organizational skills, attention to detail, and ability to anticipate potential issues.

Directions for the Company:

• Create a scenario requiring a significant network migration (e.g., data center relocation, core switch replacement, or moving from on-premises to cloud infrastructure).
• Provide details about the current environment, business constraints (e.g., maximum allowable downtime), and technical requirements.
• Include information about critical applications and their network dependencies.
• Allow 50 minutes for planning and 15 minutes for presentation.
• Have both technical and project management-focused interviewers present.

Directions for the Candidate:

• Develop a comprehensive migration plan that minimizes business disruption.
• Create a phased approach with clear milestones and contingency plans.
• Identify potential risks and mitigation strategies for each phase of the migration.
• Outline pre-migration testing procedures to validate the plan.
• Develop a rollback strategy in case of unexpected issues.
• Create a communication plan for stakeholders, including when and how you would notify affected users.
• Estimate timeframes for each phase of the migration.

Feedback Mechanism:

• After the candidate presents their migration plan, provide feedback on the comprehensiveness and practicality of their approach.
• Highlight one particularly strong element of their plan and one area that presents unaddressed risks or challenges.
• Ask the candidate to revise the identified weak area of their plan, giving them 10 minutes to develop a more robust approach.
• Evaluate their ability to incorporate feedback while defending sound planning decisions.

Frequently Asked Questions

How long should we allocate for these work sample exercises?

Each exercise is designed to take 45-60 minutes for completion, plus 15-20 minutes for presentation and feedback. We recommend scheduling no more than two exercises in a single interview day to avoid candidate fatigue. For remote candidates, consider spreading the exercises across multiple days.

Should we provide these exercises before the interview or conduct them live?

The Network Architecture Design and Migration Planning exercises can be provided 24-48 hours in advance, allowing candidates to prepare thoughtful responses. The Troubleshooting and Security Assessment exercises are more effective when conducted live, as they better simulate real-world pressure and demonstrate unscripted problem-solving abilities.

How should we evaluate candidates who use different approaches than we expected?

Focus on the effectiveness of their solution rather than adherence to a specific approach. The networking field embraces multiple valid methodologies. Evaluate whether their solution addresses the core requirements, demonstrates sound technical reasoning, and shows awareness of potential trade-offs. Different approaches often reveal valuable diverse perspectives.

What if a candidate doesn't complete the exercise in the allotted time?

This is valuable information in itself. Assess what they prioritized and how far they progressed. A candidate who methodically completes 70% of an exercise with high quality may be preferable to one who rushes through 100% with significant oversights. Discuss their time management approach during the feedback session.

How can we make these exercises fair for candidates with different backgrounds?

Ensure exercises focus on core networking principles rather than familiarity with specific vendor technologies. Allow candidates to specify which technologies they're most familiar with and adapt scenarios accordingly. Provide reference materials for syntax or specific commands to level the playing field while still testing conceptual understanding.

Should we use the same exercises for all candidates?

Yes, using consistent exercises allows for more objective comparison between candidates. However, you may have different versions of similar difficulty to prevent information sharing between candidates. The core competencies being tested should remain the same across all versions.

Finding the right Senior Network Engineer requires evaluating both technical expertise and soft skills that enable success in this critical role. These work sample exercises provide a comprehensive assessment of a candidate's abilities in real-world scenarios, revealing insights that traditional interviews often miss. By incorporating these activities into your hiring process, you'll be better equipped to identify engineers who can design, implement, and maintain the robust network infrastructure your organization depends on.

For more resources to improve your hiring process, check out our AI Job Descriptions, AI Interview Question Generator, and AI Interview Guide Generator. You can also find our comprehensive Senior Network Engineer job description at https://yardstick.team/job-description/senior-network-engineer.

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