Network Engineer III

Leidos LLC; Illinois; On-site; USD 73,000 - 133,000; Full time

Job summary

Leidos is seeking a Network Engineer III for the GSMO-II program at Scott AFB, IL, supporting the DISA Global Operations Center. This role focuses on high-availability networks, with responsibilities spanning optical/electrical transport, routing, switching, and real-time fault resolution.

The successful candidate will hold a DoD Top Secret clearance, a DoD-8570 IAT Level 2 certification, and be prepared to work a 24x7 shift in a critical defense environment, leveraging Cisco/Juniper platforms

Qualifications

• Bachelor's degree with 4+ years of relevant experience.
• DoD-8570 IAT Level 2 certification prior to start date.
• Able to work in a 24x7 shift work environment.
• Active DoD Top Secret security clearance.
• Strong knowledge of transport and IP network topologies.

Responsibilities

• Execute network operations across optical/electro-optical multiplexers, routers, and switches.
• Perform real-time circuit redesign to restore connectivity during outages and maintenance actions.
• Collaborate with customers and external agencies to maximize network availability.
• Proactively monitor network alarms using management tools.
• Manage hardware replacements, software configurations, and ASI management.
• Document outages and resolutions in incident management systems.
• Assess and resolve incidents leveraging routers, switches, CISCO, Juniper, MSPP, MPLS, SDH/SONET.

Skills

DoD 8570 IAT Level 2

Active DoD Top Secret clearance

IP/Transport networking

24x7 shift readiness

Cisco/Juniper knowledge

Education

Bachelor's degree

Tools

Solarwinds

JIRA

MS Office

Cisco IOS

Job description

POSITION SUMMARY

The Digital Sector of Leidos has multiple openings in our Joint Fires Network (JFN) NOC for a Network Engineer III supporting our Global Solutions Management-Operations II (GSMO-II) program at Scott AFB, IL. Our customer, Defense Information Systems Agency (DISA), acts as the provider of GIG/Defense Information System Network (DISN) services to its customers, the department of Defense (DoD) and national security organizations. This position directly supports the DISA-provided GIG capabilities and services in the 24x7 DISA Global Operations Center (DGOC).

PRIMARY RESPONSIBILITIES

• Execute network operations to include configuration and analysis of customer circuits across optical and electro-optical multiplexers, routers, and switches.
• Perform real-time circuit redesign (alternate routing) to restore customer connectivity during scheduled and unscheduled outages and maintenance actions.
• Work directly with internal and external customers, external government agencies, and other engineering tiers to ensure maximum network availability to minimize or eliminate mission and operational impact.
• Proactively monitor network alarms across platform specific network management tools.
• Perform a variety of change management tasks which include hardware replacement, software configurations, and ASI management.
• Utilize incident management applications to document all aspects of reported outages/degradations, isolations, escalations, and resolutions during the lifecycle of a service impacting network incident.
• Assess, identify and recommend resolutions to various network incidents and/or deficiencies leveraging knowledge in one or more of following: routers, switches, crypto devices, routing, CISCO, Juniper, MSPP, optical transport network, MPLS, time division multiplexing, SDH/SONET.

BASIC QUALIFICATIONS

• Bachelor's degree and 4+ years of prior relevant experience; or equivalent combination of education and/or experience.
• Hold DoD-8570 IAT Level 2 baseline certification (Security+ CE or equivalent) prior to start date.
• Able to work in a 24x7 shift work environment.
• Possess deep understanding of both Transport and IP network topologies.
• Must have an active DoD Top Secret security clearance.

PREFERRED QUALIFICATIONS

• Tech control facility or cyber transport experience.
• Circuit actions and vendor experience.
• IP/Transport architecture experience.
• Solarwinds and JIRA experience.
• Telco NOC, inside or outside plant experience.
• Experience with MS Office suite, i.e. Outlook, Excel, Word, Access, PowerPoint, TEAMs.
• Experience with one or more of the following: alarm surveillance, fault management, LAN maintenance, performance management, change management.

Pay Range

Pay Range $73,450.00 - $132,775.00. The 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.

Posting Details

Original Posting: August 31, 2026. 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.

About Leidos

Leidos is an industry and technology leader serving government and commercial customers with smarter, more efficient digital and mission innovations. Headquartered in Reston, Virginia, with 47,000 global employees, Leidos reported annual revenues of approximately $17.2 billion for the fiscal year ended January 2, 2026. For more information, visit www.Leidos.com.

Pay and Benefits

Pay and benefits are fundamental to any career decision. That's why we craft compensation packages that reflect the importance of the work we do for our customers. Employment benefits include competitive compensation, Health and Wellness programs, Income Protection, Paid Leave and Retirement. More details are available here.

Securing Your Data

Leidos will never ask you to provide payment-related information at any part of the employment application process. And Leidos will communicate with you only through emails that are sent from a Leidos.com email address. If you receive an email purporting to be from Leidos that asks for payment-related information or any other personal information, please report the email to [e-mail].

Commitment and Diversity

All qualified applicants will receive consideration for employment without regard to sex, race, ethnicity, age, national origin, citizenship, religion, physical or mental disability, medical condition, genetic information, pregnancy, family structure, marital status, ancestry, domestic partner status, sexual orientation, gender identity or expression, veteran or military status, or any other basis prohibited by law. Leidos will also consider for employment qualified applicants with criminal histories consistent with relevant laws.