SME Network Engineer (Lorton)

Harmonia Holdings Group, LLC is an award-winning, rapidly growing federal government contractor committed to providing innovative, high-performing solutions to our government clients and focused on fostering a workplace that encourages growth, initiative, creativity, and employee satisfaction.

SME Network Engineer

Location : Lorton, VA (22079)

Citizenship : U.S. Citizen (required for access to DHS IT systems)

Clearance : Must be able to obtain and maintain DHS / ICE Fitness Determination (Public Trust), including a favorable preliminary Fitness and full NBIS eAPP investigation (SF-85P, OF-306, SSA-89, fingerprints, PREA questionnaire if required)

Schedule : Full-time; business hours (7 : 005 : 30, MF) with required 24 / 7 on-call availability

Hybrid Work : Lorton, VA roles may telework up to 2 days per week; 3 days onsite required (subject to mission needs)

Travel : Occasional CONUS travel; local travel within 50 miles is not reimbursable

Role Overview

Harmonia Holdings Group is seeking an experienced SME Network Engineer to support DHS ICE Homeland Security Investigations (HSI) Title III and Linguists Unit (T3LU) under the CALEA program.

This role provides hands-on leadership across all network engineering functions , including architecture, routing, switching, firewall engineering, VPN and PKI integration, segmentation design, troubleshooting, and IA / accreditation-grade documentation. The SME ensures the integrity, resilience, and performance of mission-critical CALEA networks and collaborates closely with Systems, Virtualization, Storage, and Field Engineering teams to ensure end-to-end operational success.

This position supports DHSs mission while contributing to Harmonias overarching goals : delivering premier technology services, driving mission-focused innovation, sustaining organizational excellence, and being an employer of choice for skilled professionals.

Responsibilities

Network Architecture & Design

• Design, document, and maintain CALEA network architecture, including :
• Layer 2 / Layer 3 topology
• IP address schema and subnetting
• VLAN / VRF segmentation
• Routing design (OSPF, BGP, EIGRP, static routing)
• Firewall zoning, NAT policies, and security segmentation
• VPN tunnels, encrypted transport paths, and PKI integrations
• COOP / DR network routing and failover paths
• Produce and maintain authoritative network diagrams, data flows, trust boundaries, and configuration baselines.
• Evaluate, recommend, and implement enhancements to improve security, availability, and performance.

Network Operations & Troubleshooting

Firewall, Security & Accreditation Support

Interoperability & Cross-Domain Integration

COOP / DR & Lab Engineering

Documentation & Mission Coordination

Required Qualifications

Technical Proficiency

Preferred Certifications

Additional certifications may be required after hire and must be obtained within designated timelines.

Professional Competencies

Preferred Experience

Soft Skills

Physical Demands / Work Environment