Description Leidos is seeking a Sr. Network Engineer/Architect to support large-scale migration and operations on a large, high-profile DOD contract. 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 DTRA’s internal and external mission partners operating in CONUS and OCONUS locations.The Network Engineer/Architect SME supports design of a new, modernized updated and upgraded capabilities for DTRA. This role will be responsible for tech requirement definition, feasibility studies, pilot projects and implementations plans, as well as diagnosing and troubleshooting outages, monitoring networks, infrastructure and systems, and proving proactive mitigation strategies. Specifically, the candidate must have experience with SD-WAN solutions and how to transform from a Non-SDWAN. The candidate will also work with Cloud native SDN and Software Defined Access and EVPN for on-premise application. Working in a DevSecOps environment experience will be required for creating and building new solutions and perfecting them.CLEARANCE REQUIREMENT: Must hold an active Top Secret security clearance. (US Citizenship required)Primary ResponsibilitiesPlan and design secure network solutions to consolidate connectivity services under an enterprise service. Design secure wide area connectivity inclusive of underlay, overlay, and COI transport design that supports performance, quality of service, security, and mission requirements.  Provide secure access solutions leveraging wired and wireless technologies, integrating standards, use cases/scenarios, and develop associated implementation and transition plans.  Integrate capacity planning and scaling of network and security stack environments into the overall design of solutions.Collect, investigate, and identify network optimization strategies and techniques to meet capacity and performance standards.  Identify legacy service paths (i.e. dataflow, firewall rulesets, and ACLs) and develop strategies and designs for the to-be enterprise service capability to meet requirements while balancing security, sustainability, and maintainability.Support development of IP addressing schemes across IPv4 and IPv6 networks.Work with information assurance teams to ensure compliance to DoD standards to assist with providing accreditation artifacts.Basic QualificationsMinimum of a Bachelor’s degree in Science, Technology, Engineering and Math (preferred) with 8+ years' experience (additional years of directly applicable experience may be accepted in lieu of a degree).Require network certification which shall meet or exceed a CCNP (comparable vender certification accepted upon review) with CCIE preferred.Require active DoD IAT Level II (i.e. Security+) certification or equivalent prior to start. Must have broad exposure to common IT infrastructure networking in the areas of LAN, WAN, TCP/UDP, Dual stack IPv4/IPv6, IPSec, VPN, , and Firewalls Micro-segmentationMust have experience in working with two or more of the following vendor network technologies: Cisco, Juniper, F5, Aruba, Palo Alto, Dell, Brocade, and Fortinet.Experience with SD-WAN solutions, with Dell Versa preferredExperience working with Azure and AWS cloud networkingExperience working with automation tools, such as Ansible, Python scripting, CI/CD pipeline, Terraform to build an Infrastructure as Code frameworkExperience working with AAA servers, such as Cisco ISE or Aruba Clearpass, and endpoint posturing.Experience working with Enterprise WirelessFamiliarity with Type 1 encryptorsFamiliarity with Commercial Solutions for Classified (CSfC)Experience documenting logical or physical designs using drawing tools (e.g. Visio, PowerPoint, Gliffy, Cameo, MagicDraw) to depict systems, subsystems, interfaces, components, and communications of I/T applications and infrastructureExperienced and comfortable with conducting technical troubleshooting to resolve issues.Experience conducting site surveys or analyzing data obtained from site surveys.Experience creating or executing a migration plan to move circuits, network traffic, services, applications, or data between environments or to a commercial cloud provider. Alternatively, experience planning or executing a technology refresh or lifecycle refresh of an existing I/T system.Demonstrate experience in designing and implementing medium to large network infrastructure and producing corresponding technical documentation.Must be able to work as part of a team to troubleshoot and resolve complex network issues.Excellent written and verbal communication skills. This shall include drafting SOPs and technical documentation.Requires ability to communicate with executive leadership (internally or client) regarding matters of significant important to the organization/project.Must be able to present designs and plans to technical leadership personnel and boards for approvals.Preferred QualificationsCertified Cisco Network Professional (CCNP) or equivalent.Demonstrate experience in one or more of the following enterprise network management tools such as  SolarWinds, Cisco Catalyst Center, Ansible, Cisco ISE, JIRA/ConfluenceHands on experience with WAN, LAN, Dual Stack IPv4/IPv6, BGP, OSPF, EVPN, SDWAN, telecommunications and circuitsDemonstrate expertise in design and improvement of complex and geographically enterprise networks.Expert knowledge of DoD security requirements for network infrastructure.Demonstrate experience in system hardening of network infrastructure to include DoD STIG implementation.Reporting and Business Applications: Power BI, SharePointExperience providing technical leadership and oversight of teams of junior, intermediate, and senior EngineersOriginal Posting:May 12, 2025For 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 $80,600.00 - $145,700.00The 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.