Sr. Network & Systems Engineer

Leidos is seeking a Sr. Network & Systems Engineer to provide advanced engineering, strategic systems analysis, and operational oversight for large-scale operations on a high-profile Department of War (DoW) contract at Fort Belvoir, VA. The I3TS program provides enterprise-wide IT support to enable DTRA’s Information Management & Technology Directorate (ITD) to consolidate, modernize, and continuously innovate the delivery of IT services and mission capabilities to internal and external partners operating in CONUS and OCONUS locations.The Engineer will serve as a primary technical authority, exercising independent judgment to analyze and modify DTRA’s enterprise IT Server, Storage, and Network infrastructures. Operating on Unclassified, Secret, and Top-Secret networks, the candidate will lead the monitoring and troubleshooting efforts that ensure continuous, secure, and resilient access for all mission partners.Clearance: Active Top Secret/SCI security clearance at time of consideration.Work Schedule: Day Shift 0600-1800 (Sun-Wed) OR Night Shift 1800-0600 (Wed-Sat)Primary Responsibilities:The candidate's primary duties will focus on systems analysis, architectural engineering, and operational leadership:Systems Analysis & Architecture: Apply advanced systems analysis techniques to consult with DTRA leadership and mission partners, determining complex system functional specifications, capacity requirements, and architectural roadmaps. Network & Systems Engineering: Document, test, and modify network and server configurations, security protocols, and directory services (Active Directory) to align with evolving DoD Directives and security baselines. Incident & Operational Leadership: Perform shift duties as the 24x7x365 Network Operations and Security Center (NOSC) operations watch officer. Serve as the escalation authority for complex, multi-system outages, leading diagnostic strategy, event correlation, and root-cause analysis. Strategic Integration: Provide input for process improvement on operational procedures, incident response frameworks, and SLA-compliant workflow protocols. Evaluate third-party vendor solutions and manage configurations within the ServiceNow ITSM framework. Executive Advisory: Interface directly with high-level Mission Partners, DISA, Joint Forces, and Combatant Commands to advise on operational impacts, system vulnerabilities, and technical solutions. Author and present After-Action Reports (AARs) and technical briefings to senior leadership. Support Tier I–III system, networking, and engineering personnel to ensure network troubleshooting efforts. Oversee real-time monitoring of global enterprise networks using DoD-approved tools (e.g., SolarWinds). Develop and enforce operational procedures, incident response workflows, and escalation protocols.  Interface with Mission Partners, DISA, Joint Forces, and Combatant Commands on network status, issues, and operational impacts. Prepare and deliver operational briefs, after-action reports (AARs), and executive summaries to senior leadership.  Troubleshoot, resolve, and/or escalate technical issues based on ticket assignments, deskside or remotely, as necessary. Correlate events and incidents for management of Information Technology (IT) Services. Required QualificationsEducation & Experience: BS degree in Computer Science, Information Technology, or a related engineering field with 8–12 years of experience, or a Master's degree with 6–10 years of experience in enterprise systems engineering, network design, or IT operations management. Specific high-level technical experience may be considered in lieu of a degree. Technical Expertise: Advanced, theoretical, and practical understanding of network protocols (TCP/IP, DNS, DHCP, VPNs, firewalls), system virtualization, and enterprise storage networks. Tools & Frameworks: Proficiency in administering enterprise monitoring suites (e.g., SolarWinds), Active Directory architecture, and IT Service Management (ITIL/ITSM) frameworks. Security Certification: Must possess a current DoD 8570.01-M IAT Level II certification (e.g., Security+ CE) or higher prior to start. Clearance: Active Top Secret/SCI security clearance at time of consideration.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:September 29, 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