Network Security Engineer

CDH Professionals; Utrecht; Hybrid; EUR 67,000 - 100,000; Full time

Job summary

CDH Professionals in the Netherlands seeks an experienced Freelance Network Security Engineer to support an organisation in Utrecht with managing, maintaining and optimizing its network and security infrastructure.

This hands-on role covers enterprise firewalls, VPNs, routing, switching and security monitoring, with a hybrid/on-site work arrangement and start ASAP for an initial 6-month contract.

Qualifications

• 5+ years of experience as a Network Engineer, Network Security Engineer or Infrastructure Engineer.
• Strong knowledge of TCP/IP, DNS, DHCP, VLANs and VPNs.
• Hands-on experience with enterprise firewalls such as Fortinet, Palo Alto or Cisco.
• Strong understanding of routing and switching.
• Experience with OSPF and/or BGP.
• Experience with network security, segmentation and access controls.
• Experience with network monitoring and troubleshooting.
• Knowledge of IDS/IPS and general network security principles.
• Experience working within enterprise IT environments.
• Strong problem-solving and communication skills.
• Comfortable working independently in a freelance environment.
• Available to work in or around Utrecht.

Responsibilities

• Manage, maintain and troubleshoot network and security infrastructure.
• Configure and manage enterprise firewalls and security appliances.
• Manage LAN/WAN infrastructure, routing and switching.
• Configure and maintain VPN solutions.
• Manage VLANs, network segmentation and access controls.
• Monitor network performance, availability and security.
• Troubleshoot complex network connectivity and security issues.
• Investigate network security events and potential vulnerabilities.
• Perform firewall rule changes, security configuration and maintenance.
• Support network upgrades, migrations and infrastructure projects.
• Identify opportunities to improve network security, performance and reliability.
• Work closely with infrastructure, cloud and cybersecurity teams.
• Maintain accurate network documentation and technical procedures.

Job description

Duration: 6 month initial freelance contract, with possible extension

Location: Utrecht, Netherlands

Working arrangement: Hybrid / On-site

Start: ASAP

About the Role:

We are looking for an experienced Freelance Network Security Engineer to support an organisation in Utrecht with the management, maintenance and optimisation of its network and security infrastructure.

This is a hands‑on technical role suited to a Network Security Engineer who is comfortable working across enterprise networking, firewalls, VPNs and network security technologies. You will be responsible for maintaining a secure and reliable network environment while supporting infrastructure improvements and troubleshooting complex technical issues.

Responsibilities:

• Manage, maintain and troubleshoot network and security infrastructure.
• Configure and manage enterprise firewalls and security appliances.
• Manage LAN/WAN infrastructure, routing and switching.
• Configure and maintain VPN solutions.
• Manage VLANs, network segmentation and access controls.
• Monitor network performance, availability and security.
• Troubleshoot complex network connectivity and security issues.
• Investigate network security events and potential vulnerabilities.
• Perform firewall rule changes, security configuration and maintenance.
• Support network upgrades, migrations and infrastructure projects.
• Identify opportunities to improve network security, performance and reliability.
• Work closely with infrastructure, cloud and cybersecurity teams.
• Maintain accurate network documentation and technical procedures.

Requirements:

• 5+ years of experience as a Network Engineer, Network Security Engineer or Infrastructure Engineer.
• Strong knowledge of TCP/IP, DNS, DHCP, VLANs and VPNs.
• Hands‑on experience with enterprise firewalls such as Fortinet, Palo Alto or Cisco.
• Strong understanding of routing and switching.
• Experience with OSPF and/or BGP.
• Experience with network security, segmentation and access controls.
• Experience with network monitoring and troubleshooting.
• Knowledge of IDS/IPS and general network security principles.
• Experience working within enterprise IT environments.
• Strong problem‑solving and communication skills.
• Comfortable working independently in a freelance environment.
• Available to work in or around Utrecht.

Ideal Profile:

• Hands‑on and technically strong Network Security Engineer.
• Strong troubleshooting and analytical skills.
• Security‑focused with a proactive approach to identifying and resolving issues.
• Comfortable working independently and taking ownership of technical tasks.
• Strong communication skills and able to work with multiple technical teams.
• Experience working in complex enterprise network environments.
• Available at short notice or with a short notice period.
• Freelance / ZZP contract
• Initial 6 month contract
• Hybrid role: combination of on‑site work in Utrecht and remote working
• Full‑time assignment
• Competitive freelance rate, depending on experience