Sr. Network Engineer w/active Top Secret clearance

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, maintain, and sustain 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, implement, configure, test, maintain, and sustain enterprise network infrastructure and services across all sites.

• Develop logical and physical network designs based on performance, availability, security, and operational requirements.

• Engineer resilient connectivity across sites, datacenters, cloud, wide-area networks, and other distributed environments.

• Apply sound principles for addressing segmentation, routing, switching, traffic management, and access control.

• Monitor network health, capacity, latency, availability, and utilization.

• Troubleshoot complex network issues using structured analysis, packet-level inspection, telemetry, logs, and performance data.

• Establish redundancy, failover, fault isolation, and recovery mechanisms.

• Integrate network security controls consistent with zero-trust and defense-in-depth principles.

• Develop repeatable configurations, validation procedures, automation, and infrastructure-as-code practices.

• Maintain accurate diagrams, configurations, interface definitions, operating procedures, and change records.

• Participate in change management, incident response, root-cause analysis, and corrective-action planning.

• Collaborate with systems, network, cybersecurity, and operations teams.

• Evaluate technologies based on standards compliance, interoperability, lifecycle cost, supportability, and mission suitability.

• Design and implement network automation that standardizes configuration, testing, deployment, monitoring, and compliance while reducing human error and accelerating the delivery of reliable network services.

• 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.

FOUNDATIONAL SKILLS

• Network models, packet flow, encapsulation, and protocol behavior.

• IPv4 and IPv6 addressing, subnetting, name resolution, and address-management principles.

• Layer 2 and Layer 3 networking, routing, switching, and segmentation.

• Transport protocols, application traffic patterns, and quality-of-service principles.

• Network security, encryption, access control, secure remote access, and traffic inspection.

• Wide-area, datacenter, cloud, and software-defined networking concepts.

• High availability, redundancy, load distribution, and failure-domain design.

• Network monitoring, telemetry, logging, packet analysis, and performance engineering.

• Scripting, automation, version control, and configuration-management fundamentals.

• Structured troubleshooting and root-cause analysis.

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.

Qualifications

Required:

• Bachelor's degree in a related field or equivalent experience.

• 8+ 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 - $220,000

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