Senior Network Security Engineer

Senior Network Security Engineer, Network Data

Position Type: 6-Month Contract (Strong Renewal Potential)

Number of openings:1,

Location: Mississauga, ON (Hybrid: 2–3 days onsite per week

Must be eligible to work in Canada

Clearance: Must be eligible for Government of Canada Protected B clearance (requires living in Canada for approximately the last 5 years)

Roles and responsibilities

We are seeking a versatile Senior Network Security Engineer, Network Data to support critical enterprise infrastructure initiatives, centered on an active, large-scale data centre migration. In this role, you will play a hands-on technical lead role translating and migrating hundreds of firewall configurations from legacy platforms to next-generation appliances, while supporting core enterprise LAN/WAN operations.

The ideal engineer thrives across the entire network stack, is comfortable wearing multiple hats, and brings proven experience executing data center migrations with automation.

Key Responsibilities

• Data Centre & Firewall Migration: Lead the translation, validation, and deployment of configurations migrating approximately 500 firewalls from Cisco to Fortinet.
• Traffic Management & Security Implementation: Build, maintain, and optimize F5 BIG-IP traffic management solutions, including custom iRule programming.
• Network Automation: Develop and execute Ansible playbooks and Python scripts to streamline configuration deployments, testing, and operational tasks.
• Operations & Tier 2/3 Support: Provide senior-level escalation support for enterprise routing, switching, and firewall incidents; isolate complex Layer 1–7 issues.
• Security & Change Execution: Implement approved security directives (firewall rules, IP/subnet filtering, VPN policies) and execute planned changes during scheduled maintenance windows.
• Documentation & Standards: Maintain precise network topologies, operational runbooks, and migration mapping records.

Required Technical Competencies

• Fortinet / FortiGate (Must-Have): Deep, hands-on engineering, configuration, policy mapping, and operational experience.
• Cisco Firewalls & Enterprise Networking: Proven track record managing Cisco firewall appliances in a migration context, alongside solid routing and switching expertise (OSPF, BGP, LAN/WAN).
• F5 BIG-IP: Strong, practical experience with Local Traffic Manager (LTM) and hands-on iRule development.
• Automation & Scripting: Demonstrated proficiency writing and running Ansible playbooks; working ability to read and maintain Python scripts.
• Data Centre Migration Track Record: Prior experience actively planning and executing data centre migrations in an enterprise environment.

Qualifications & Working Conditions

• Experience: 8+ years of enterprise networking, firewall administration, and infrastructure delivery experience.
• Versatility: Comfortable tackling issues across the full technology stack with minimal ramp-up time.
• Availability: Open to occasional evening/weekend maintenance windows for project cutovers.
• Certifications (Asset): CCNP, CCIE, NSE 4+, or F5-CTS.
• Cloud Knowledge (Asset): Familiarity with hybrid connectivity involving Azure or AWS environments.