Network Security Engineer

Role: Senior Network & Security Infrastructure Engineer

Location: Brussels, Belgium (Hybrid Onsite/Remote)

Contract Type: Full-Time freelance project

Opportunity Overview

A leading international organisation is seeking an experienced Network & Security Infrastructure Engineer with strong technical expertise to support the design, deployment, and optimisation of large-scale enterprise network environments.

This role is highly technical and not suited for candidates with purely managerial backgrounds. The ideal engineer will be hands-on, highly capable with core networking technologies, and confident in troubleshooting and implementing advanced routing, switching, and security protocols across hybrid infrastructures.

Key Responsibilities

• Modernise and expand enterprise Wi-Fi infrastructure, including the replacement of legacy access lines and integration of user-friendly authentication systems.
• Evaluate and implement next-gen antenna solutions to improve wireless coverage and performance.
• Support integration efforts between data centre environments across different geographies.
• Configure and transition DHCP/DNS infrastructures and facilitate seamless Active Directory account integrations.
• Drive software-defined network expansion, focusing on advanced datacentre fabric technologies.
• Transition legacy load balancing platforms to virtualised appliances, while optimising traffic within inter-cloud routing environments.
• Introduce enhanced network orchestration and automation tools to align with evolving stakeholder needs.

Technical Skill Requirements

Hands-on experience is mandatory in the following areas:

• Network Topologies: Hierarchical architecture (Core, Distribution, Access), and Leaf-Spine models
• Routing Protocols:
• OSPF (including NSSA, STUB areas)
• IS-IS (Level 1 & 2)
• BGP (Local Preference, AS-Path, MED, Community Strings)
• BGP Address Families: VPNv4, MDT
• Traffic Engineering: Route Redistribution, VLAN/VRF design, MPLS (LDP, L3VPN, Route Distinguishers/Targets)
• Multicast Routing: PIM, MSDP, Rendezvous Point (RP) setup
• SDN & Automation: Cisco ACI, APIC, multipod and multisite deployment, Nexus Dashboard

Profile

• Minimum 8 years' experience in network engineering, infrastructure, or security roles
• Strong technical acumen in designing and securing enterprise-grade networks
• Able to work independently on complex integration and migration tasks
• Comfortable supporting multi-site or hybrid cloud environments
• Fluent in English and French (verbal and written)
• Degree in Information Technology, Telecommunications, or related discipline preferred