Sr. Network Engineer w/active Top Secret clearance

LMI; Washington (District of Columbia); On-site; USD 111,000 - 192,000; Full time

Job summary

LMI is seeking a Network Engineer to design, build, and maintain classified network infrastructure across multiple government sites, including TS/SCI environments, in the Washington, DC area.

The role requires 5+ years of network engineering experience, familiarity with RMF/NIST, and certifications such as CCNA/CCNP. Travel 25-50% and security clearance eligibility are required.

Qualifications

• 5+ years of network engineering experience, including in classified environments.
• Knowledge of routing, switching, and network security fundamentals.
• Familiarity with RMF per NIST SP 800-37/800-53 for security authorization.
• Certifications such as CCNA/CCNP/Security+ are preferred.

Responsibilities

• Design, install, configure, and maintain classified network infrastructure across facility locations.
• Troubleshoot network performance, connectivity, and security issues.
• Support cross-domain solutions and secure network interconnects between sites.
• Collaborate with security and systems teams to ensure accreditation requirements are met.
• Maintain network documentation, diagrams, and configuration baselines.
• Support VTC and conference room AV capability across program sites.

Skills

5+ years network engineering

Routing & Switching

Network security fundamentals

RMF/NIST knowledge

SCIF/classified familiarity

Education

Bachelor's degree in a related field

Tools

CCNA

CCNP

Security+

Job description

Overview

LMI is a new breed of digital solutions provider dedicated to accelerating government impact with innovation and speed. Investing in technology and prototypes ahead of need, LMI brings commercial-grade platforms and mission-ready AI to federal agencies at commercial speed. Leveraging our mission-ready technology and solutions, proven expertise in federal deployment, and strategic relationships, we enhance outcomes for the government, efficiently and effectively. With a focus on agility and collaboration, LMI serves the defense, space, homeland, healthcare, and intel sectors - helping agencies navigate complexity and outpace change. Headquartered in Tysons, Virginia, LMI is committed to delivering impactful results that strengthen missions and drive lasting value.

Responsibilities

LMI is seeking a skilled Network Engineer to design, build, and maintain classified network infrastructure supporting enterprise IT operations across three geographically dispersed government sites, including two greenfield SCIF facilities serving TS/SCI users. This individual will work with cross-functional teams to ensure reliable, secure connectivity across multiple locations.

Primary Duties Include

• Design, install, configure, and maintain classified network infrastructure across facility locations.
• Troubleshoot network performance, connectivity, and security issues.
• Support cross-domain solutions and secure network interconnects between sites.
• Collaborate with security and systems teams to ensure networks meet accreditation requirements.
• Maintain network documentation, diagrams, and configuration baselines.
• Support design and integration of video teleconferencing (VTC) and conference room AV capability across all program sites, including classified and unclassified variants.
• Support network and security operations center (NOC/SOC) functions, including monitoring tools, coverage models, and 24x7 support where required .

Location

This position is based in the Washington, DC metro area, with travel to program locations.

Travel

This position requires approximately 25-50 % travel to support activities across multiple program locations.

Required

• Bachelor's degree in a related field or equivalent experience.
• 5+ years of network engineering experience, including in classified environments.
• Working knowledge of routing, switching, and network security fundamentals.
• Relevant certification (e.g., CCNA, CCNP, Security+).
• Familiarity with ICD 705 physical security standards for SCIF design and accreditation.
• Familiarity with the Risk Management Framework (RMF) per NIST SP 800-37 and NIST SP 800-53 for system security authorization.

Nice To Have

• Experience supporting cross-domain or multi-level security network solutions.
• Experience deploying networks in newly constructed or renovated facilities.
• Demonstrated experience leading or supporting large, geographically dispersed teams.
• Experience supporting Special Access Program (SAP) facilities, systems, or environments.

TS/SCI clearance and SAP eligibility are required for this position. Applicants selected will be subject to a government security investigation and must meet eligibility requirements for access to classified information. LMI will only consider applicants with current security clearances. Please note that only U.S. citizens are eligible for a security clearance.

Target salary range: $111,000 - $192,000

Disclaimer

The salary range displayed represents the typical salary range for this position and is not a guarantee of compensation. Individual salaries are determined by various factors including, but not limited to location, internal equity, business considerations, client contract requirements, and candidate qualifications, such as education, experience, skills, and security clearances.

Job Locations

US-DC-Washington, DC