Network Security Engineer M - Strasbourg - Freelance H/F - collectivite

Important informationContract type: FreelanceDaily rate: 500Location: Strasbourg, FranceStarting date:2 to 4 weeksWork mode: OnsitePublished on: 9 July 2026What they needThe contextOur client is a large organisation operating in a complex and highly secure network environment, combining on-premise infrastructure and cloud technologies. The network and security teams work on critical perimeters, within a rigorous framework of change management and security rule lifecycle.The roleThe Network Security Engineer is responsible for the configuration, deployment and troubleshooting of network and security equipment, in a demanding multi-technology environment. Position based on site in Strasbourg.This is a freelance mission with an expected duration of up to 2 years.Your missions- Configure, deploy and troubleshoot FortiGate and Checkpoint firewalls- Configure, deploy and troubleshoot Cisco ACI infrastructures- Configure, deploy and troubleshoot F5 load balancers- Configure, deploy and troubleshoot Certes Technologies solutions- Administer and evolve cloud network technologies- Manage the firewall rule lifecycle and change management processes via ServiceNowPosition based in Strasbourg - 100% on site + EU nationality mandatory (European institutions context).Profile wantedEssential- Solid experience in cloud environments- Experience within a large organisation: banking, military or service operator sector- Mastery of Checkpoint and FortiGate firewalls- Experience in change management and security rule lifecycle (ServiceNow)- Network security skills (GIS)- Knowledge of ACI (hands-on experience or solid fundamentals)- Mastery of network fundamentals: IP subnetting, VLANs- Fluent English (B2 minimum)Key skills- Rigour and troubleshooting ability in complex environments- Excellent communication skills- Autonomy and sense of responsibilityExperience: 5 years minimum.