Senior Network Engineer (Freelance optional)

Job Description

We are looking for a skilled and motivated Senior Network Administrator to design, deploy, secure, and optimise the organisation's network infrastructure in a hybrid environment. The Senior Network Administrator plays a key role in the transition toward a state-of-the-art infrastructure, aligned with modern technological constraints and the evolving needs of the organisation. In this role, you will collaborate closely with experts in telecommunications, infrastructure engineering, and IT operations.

This role is situated within a highly sensitive public-service environment that supports complex judicial investigations and critical operations in Belgium and, when required, abroad.

The team provides technical and tactical support, including real-time interception and observation of telecommunications. It also maintains the necessary infrastructure and develops solutions to improve the effectiveness of these activities.

You will join a specialised team working with advanced systems and technologies used in critical investigative contexts.

️ Responsibilities:

Network Architecture & Infrastructure Management

• Design, deploy, and manage physical and virtual networks in hybrid environments (on-premise & cloud).
• Administer, configure, and maintain LAN/WAN/WLAN infrastructures.
• Participate in the evolution of network architecture based on application and service requirements.
• Work with infrastructure teams to implement SDN and other virtualised network services.
  
  
  

Security & Reliability

• Ensure the security, resilience, and reliability of network and communication systems.
• Manage firewalls, VPNs, load balancers, IDS/IPS, and other network security solutions.
• Define, implement, and maintain network security policies and best practices.
• Identify vulnerabilities and contribute to mitigation strategies.
  
  
  

Operations & Troubleshooting

• Monitor network performance and proactively detect anomalies.
• Diagnose and resolve complex connectivity, performance, and configuration issues.
• Support incident response and ensure timely resolution of critical problems.
• Maintain and update network documentation, configurations, and operational procedures.
  
  
  

Project Participation & Collaboration

• Contribute to infrastructure and migration projects, including virtualisation and modernisation initiatives.
• Work closely with system, security, and telecom experts to ensure solution consistency.
• Take ownership of assigned tasks, assess risks, and escalate when necessary.
• Contribute as a team player while being fully capable of working independently.
  
  
  

Continuous Improvement & Technology Watch

• Conduct technology watch and propose improvements aligned with industry trends.
• Promote continuous improvement approaches and pragmatic, solution-oriented practices.
• Support knowledge sharing and contribute to internal expertise development.
  
  
  

Required Experience

• 5-7+ years of experience in network administration, ideally in hybrid or critical environments.
• Strong command of Cisco, Fortinet, or equivalent technologies.
• Excellent knowledge of network protocols and technologies: TCP/IP, VLAN, BGP, OSPF, QoS, MPLS, routing & switching.
• Proven experience with firewalls, VPNs, IDS/IPS, and segmentation strategies.
• Experience with virtualisation and modern network technologies, including SDN and virtualised network services.
• Familiarity with network monitoring and management tools.
  
  
  

Soft Skills & Professional Qualities

• Bachelor's or master's degree in IT, networking, or equivalent professional experience.
• Strong analytical mindset with a focus on continuous improvement.
• Pragmatic, solution-oriented approach to technical challenges.
• Curious, proactive, and eager to learn new technologies.
• Excellent written and verbal communication skills, with the ability to explain complex topics clearly.
• Discrete, stress-resistant, and reliable in critical environments.
• Ability to work autonomously while contributing effectively to team objectives.
• Fluent in French or Dutch, with a solid understanding of the other language.
• Good command of written and spoken technical English.
• A certification in CCNP, CCIE, NSE, PCNSE, or equivalent is a plus.
  
  
  

A 'TOP SECRET' level security clearance is required for this position, as referred to in the law of 11/12/1998 on classification, security clearances, attestations and notices.

Location: Etterbeek (Brussels)

Your profile

Experience as: Expert Network Engineer

Skills

• CISCO
• firewalls, VPNs, load balancers, IDS/IPS
• fortinet
• LAN/WAN/WLAN
• MPLS, routing & switching
• Network Administration
• Network Architecture
• SDN
• TCP/IP, VLAN, BGP, OSPF, QoS
  
  
  

Languages

• Dutch or French
• English
  
  
  

Offer

You will be part of a growing Belgian SME where initiative and personal development are encouraged. We will provide you with an enjoyable work environment with fun colleagues. We will work out a career plan with you, with attention and a budget for extra education/certification. You can count on an attractive salary, supplemented with extra-legal benefits, including a company car.

(Freelance is also possible)