Senior Network Engineer

Leidos is seeking an experienced and motivated Senior Network Engineer to support the Defense Threat Reduction Agency (DTRA) on the Integrated Information Technology Support Services (I3TS) contract in Fort Belvoir, VA or Albuquerque, New Mexico . This contract is a critical initiative to modernize and operate DTRA's enterprise IT systems. The successful candidate will play a key role in enhancing IT efficiency, security, and mission effectiveness by designing, implementing, and maintaining a resilient and secure network infrastructure. This role will be instrumental in supporting the agency's mission to counter and prevent emerging global threats.Clearance: Active Top Secret (TS) clearance with SCI eligibility.Primary Responsibilities:Design, deploy, and maintain robust network infrastructure to support enterprise systems and data pipelines.Configure and optimize network hardware including routers, switches, firewalls, load balancers, and VPN solutions to ensure secure and reliable connectivity.Manage and support Unified Communications, including Cisco Call Manager (CUCM), to ensure seamless voice and video collaboration.Lead complex network engineering projects, including system upgrades, migrations, and new deployments.Implement and manage network access control (NAC) using Cisco Identity Services Engine (ISE), including device profiling, posture assessment, and policy enforcement to support a Zero Trust architectureMonitor network performance, troubleshoot latency and bandwidth issues, and implement changes to improve stability and throughput.Implement and manage routing protocols such as BGP and OSPF.Configure, and maintain TACLANE high-assurance cryptographic encryptors, including the implementation of Agile VLAN for Layer 2 security.Troubleshoot and support portable, deployable "fly-away kits" for remote and tactical communications needs.Create and maintain comprehensive documentation, including detailed network diagrams, system engineering plans, and technical standards.Ensure the network design complies with all security policies, supports scalability, and aligns with operational and mission requirements, including the implementation of Zero Trust principles.Collaborate with government partners, engineers, and other stakeholders to translate operational and strategic requirements into scalable, production-ready solutions.Mentor and guide junior network engineers, providing technical oversight and sharing knowledge.Basic Qualifications:Active Top Secret (TS) clearance with SCI eligibility.Bachelor’s degree in Computer Science, Electrical/Network Engineering, Information Systems, or a related technical discipline with 8-12 years of relevant experience, OR a Master’s degree with 6-10 years of relevant experience.Current DoD 8570/8140 baseline certification (Security+ and CCNA).Proven experience in engineering and sustaining enterprise network infrastructure in DoD or other federal environments.Hands-on experience with routing and switching protocols (BGP, OSPF), network security (NGFW, IDS/IPS), and load balancing.Experience with configuring routers, switches, firewalls, load balancers, and VPN solutions from vendors like Cisco, and Palo Alto.Preferred Qualifications:Advanced networking certifications such as Cisco CCNP or CCIE.Experience with high-assurance cryptographic devices, specifically TACLANE (KG-175).Experience with Cisco Unified Communications Manager (CUCM).Experience with network automation and Infrastructure as Code (IaC) tools like Ansible .Familiarity with Zero Trust network segmentation and micro-segmentation.Experience supporting large-scale enterprise data, analytics, or platform services in secure environments.Experience with Remedy or ServiceNow ticketing systems.Familiarity with TACLANE management (e.g. GemOne, CHIMERA, VINE)Experience with Cisco Nexus switching platforms and expertise in software-defined networking (SDN) solutions, particularly Cisco ACI, for data center automation and micro-segmentation.If you're looking for comfort, keep scrolling. At Leidos, we outthink, outbuild, and outpace the status quo — because the mission demands it. We're not hiring followers. We're recruiting the ones who disrupt, provoke, and refuse to fail. Step 10 is ancient history. We're already at step 30 — and moving faster than anyone else dares.Original Posting:July 22, 2026For U.S. Positions: While subject to change based on business needs, Leidos reasonably anticipates that this job requisition will remain open for at least 3 days with an anticipated close date of no earlier than 3 days after the original posting date as listed above.Pay Range:Pay Range $92,300.00 - $166,850.00The Leidos pay range for this job level is a general guideline only and not a guarantee of compensation or salary. Additional factors considered in extending an offer include (but are not limited to) responsibilities of the job, education, experience, knowledge, skills, and abilities, as well as internal equity, alignment with market data, applicable bargaining agreement (if any), or other law.SummaryLocation: Fort Belvoir, VAType: Full time