Senior Security Network EngineerContract Type: Freelance 12 months, then option to become permanent.Overview:Our client, a well-established IT consulting company, is seeking a Senior Network Security Engineer to join their growing team. The ideal candidate will be highly autonomous, collaborative, and comfortable working in a distributed team across multiple geographies. This is an exciting opportunity to work with a talented team primarily based in Portugal, while engaging with stakeholders and team members across the globe.Key Responsibilities:Design, implement, and maintain complex network infrastructures.Collaborate with network engineers based in Italy, Portugal and other global team members.Troubleshoot and resolve network issues across diverse environments.Contribute to network architecture planning and security best practices.Ensure high availability and performance of critical network systems.Communicate clearly and proactively with both local and international teams.Document configurations, procedures, and troubleshooting guides.Technical Skills for Senior Network EngineerSwitching and Routing: Minimum 5+ years of experience in troubleshooting, implementation, and advisory.Security Firewalls: Minimum 5+ years of experience in troubleshooting, implementation, and advisory. This is the primary skill focus.Fortinet or F5 Load Balancing Devices: Minimum 5+ years of experience in troubleshooting, implementation, and advisory.Wi-Fi Networking: Minimum 3+ years of experience in troubleshooting, implementation, and advisory.Cisco ACI (Application Centric Infrastructure): Minimum 2+ years of experience in troubleshooting, implementation, and advisory.Preferred Qualifications:Cisco certifications (e.g., CCNP, CCIE) or equivalent.Experience in large enterprise or consulting environments.Familiarity with automation tools and scripting for network management.