Network Engineer *Active Top Secret Required*

Seeking an experienced Network Engineer to support the U.S. Department of the Treasury’s mission-critical classified IT system that enables Treasury’s national security, intelligence, and counter-threat finance missions.

The selected candidate will operate within a Secure Compartmented Information Facility (SCIF) and be responsible for ensuring the reliability, security, and performance of Treasury’s classified network infrastructure supporting the Treasury Foreign Intelligence Network (TFIN).

This role supports both day-to-day network operations and ongoing modernization efforts in a highly secure environment.

Responsibilities

• Build, configure, and maintain the day-to-day operation of the Treasury Foreign Intelligence Network (TFIN).
• Manage and support Cisco network devices including routers, switches, enterprise firewalls, controllers, and wireless access points.
• Configure, maintain, and troubleshoot firewall policies, access control lists (ACLs), and VPN connectivity in support of mission and security requirements.
• Protect data, software, and hardware by implementing and maintaining DISA STIGs, NIST 800-53, and CNSS 1253 compliant security controls.
• Troubleshoot, diagnose, and resolve complex hardware, software, and connectivity issues across LAN/WAN environments.
• Support secure Video Teleconferencing (VTC) services, including network connectivity, firewall traversal, Quality of Service (QoS), and coordination with system and VTC support teams.
• Support disaster recovery and continuity of operations planning and execution.
• Monitor, analyze, and optimize network performance using tools such as SolarWinds and Wireshark.
• Maintain network documentation including block diagrams, Simple Network Diagrams (SND), and Detailed Network Diagrams (DND).
• Assist in the development of IATT and ATO packages and ensure ongoing accreditation compliance.
• Research, test, and implement emerging network technologies to enhance performance and security.
• Participate in customer briefings, design reviews, and after-action reports., * Active Top Secret clearance with SCI eligibility (final, favorable adjudication).

• Minimum 5 years of experience supporting network operations in a federal, DoD, or Intelligence Community environment.
• Demonstrated expertise with Cisco enterprise network devices and architectures.
• Hands-on experience supporting enterprise firewall technologies in a secure or regulated environment.
• Strong understanding of LAN/WAN design, network protocols, VLANs, VPNs, and Quality of Service (QoS).
• Experience applying DISA STIGs and NIST security frameworks.
• Proficiency with network monitoring and diagnostic tools (e.g., SolarWinds, Wireshark).
• Strong documentation, communication, and analytical skills.

Desired

• Bachelor’s degree in Information Technology, Computer Science, Network Engineering, or related field.
• Industry certifications such as CCNP, CCNA, Security+, or Network+.
• Experience supporting classified or Intelligence Community networks.
• Familiarity with secure VTC or unified communications environments.
• Exposure to Citrix, hybrid AWS/Azure environments, or Treasury systems.

Tenacity Solutions, LLC is a Certified Service-Disabled Veteran-Owned Small Business (SDVOSB) and SBA-certified 8(a) firm delivering high-impact solutions to federal and state government clients. We operate in complex, mission-critical environments and provide reliable, data-informed execution that keeps operations running and improving. From secure IT environments and network operations to data-driven decision support and critical operational services, Tenacity brings the discipline, speed, and precision required to perform in high-pressure settings. Whether enabling mission continuity, improving system performance, or streamlining workforce operations, our focus is always on outcomes that matter, executed with accountability, adaptability, and purpose.