Description Leidos is seeking an experienced Senior Network Engineer to provide network operations and engineering sustainment support to a mission critical IP messaging and communications transport network. A successful candidate will develop an understanding of the services offered to external organizations, provide lifecycle systems engineering support to development and operations on the program, and use a combination of technical and functional expertise to recommend solutions to satisfy customer requirements. Primary Responsibilities: Network integration, testing, security engineering, and implementation configuration support. Collaborate with network architects to define and/or continuously improve STIG compliant configuration baselines, versioning, and compliance tracking. Test and validate automation and best practice insertion opportunities. Lead development of SOPs/TTPs. Support Continuous Service Improvements (CSI). Support system performance tuning and enhancements. Create and maintain Engineering Implementation Plans (EIP). Support tier escalation of incident management support tasks. Active participation in Root Cause Analysis (RCA) for Problem Management activities. Participate in engineering meetings to bridge the gap between operations and engineering providing operational readiness for new solutions projected to be deployed into production. Perform highly technical maintenance involving firewalls, VPNs, IPS, and load balancers. Provide expert knowledge of network engineering and operations, large scale enterprise network solution implementation and transition to Network Operations, as well as test and evaluation activities. Perform highly technical maintenance involving network devices routers, switches, security solutions, and WANX. Core Qualifications: BS degree and 8 to 12 years of prior relevant experience or a Masters with 6 to 10 years of prior relevant experience. (Additional years of related work experience may be substituted for a degree at the Hiring Manager's discretion). Effective written and oral communication and problem-solving skills Active DoD clearance at the Top-Secret level with SCI eligibility Security+ Certification or other DOD 8570 IAT Lvl II Certification within a certain timeframe after starting if not starting with one when hired. Extensive knowledge of defense-in-depth principles, Network and Security architecture, network topology, IT device integrity, and common security elements. 8+ years' experience engineering and troubleshooting networks, including extensive routing and switching experience such as one or more of the following: MPLS, VPNs, routing protocols i.e. BGP, OSPF, IS-IS, switching protocols i.e. Spanning Tree Protocol, VLANs, LLDP, VoIP, Multicast protocols and emerging network technologies. Strong understanding and in-depth knowledge of IP network/subnet addressing. Experienced and adept at developing and maintaining technical documents, analyses, and reports. Experience developing and presenting technical information to senior customer management, customer stakeholders, and company management. Hands-on experience deploying, configuring and troubleshooting Cisco enterprise network routing, switching and firewall/security devices. Ability to travel up to 10% OCONUS travel. Preferred Qualifications: Extensive SME level knowledge of network engineering and operations, integration, test and evaluation activities, as well as implementation and transition to Network Operations processes and concepts Cisco CCNP Route/Switch and/or CCNP Security Experience and with and practical understanding of enterprise WAN principles. Experience with change, configuration and performance management NetOps concepts. IAT Level III Certification (i.e. CISSP or equivalent). Come break things (in a good way). Then build them smarter. We're the tech company everyone calls when things get weird. We don't wear capes (they're a safety hazard), but we do solve high-stakes problems with code, caffeine, and a healthy disregard for how it's always been done. Original Posting: July 30, 2025 For 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 $89,700.00 - $162,150.00 The Leidos pay range for this job level is a general guideline onlyand 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.