Network Administrator | On-site | Santa Rita, Guam | Top Secret Clearance

The Operational Technology (OT) Network Administrator will provide senior-level network engineering, administration, cybersecurity, and technical support for Facility-Related Control Systems (FRCS), Industrial Control Systems (ICS), Building Management Systems (BMS), and related Operational Technology environments supporting Naval Facilities Engineering Systems Command, Marianas (NAVFACMAR).

This position is responsible for designing, managing, securing, and troubleshooting complex industrial and building automation network infrastructure supporting mission-critical facility operations. The environment includes Supervisory Control and Data Acquisition (SCADA) systems, Programmable Logic Controllers (PLCs), Direct Digital Controllers (DDCs), HVAC systems, power distribution systems, life-safety sensors, and other facility control technologies.

The successful candidate will possess advanced knowledge of OT network architecture, industrial routing and switching, network segmentation, firewall administration, industrial protocols, cybersecurity controls, and DoD Risk Management Framework (RMF) requirements. All network administration activities must follow an OT-safe, safety-first approach designed to maintain deterministic network performance, high availability, and continuity of critical physical processes.

Essential Duties and Responsibilities

• Configure, administer, secure, and troubleshoot industrial and OT network infrastructure, including switches, routers, firewalls, Data Diodes, and related technologies.
• Design, maintain, and support resilient Layer 2 and Layer 3 network architectures for FRCS, ICS, SCADA, and BMS environments.
• Manag industrial network redundancy and resiliency technologies, including Resilient Ethernet Protocol (REP), Device Level Ring (DLR), and similar technologies supporting rapid failover and deterministic traffic flow.
• Implement and maintain network segmentation and micro-segmentation using the Purdue Enterprise Reference Architecture/Purdue Model.
• Configure and manage OT-specific Next-Generation Firewalls, access control lists, and Unidirectional Gateways/Data Diodes.
• Manage Ports, Protocols, and Services Management (PPSM) requirements across IT/OT boundaries.
• Support industrial and building automation protocols including BACnet/IP, LonWorks, Modbus TCP, DNP3, CIP, Fox Protocol, and related technologies.
• Apply and maintain network-specific Security Technical Implementation Guides (STIGs) using OT-safe methodologies that minimize the risk of disruption to physical equipment and facility operations.
• Serve as the Tier III escalation point for complex network outages, packet loss, routing failures, connectivity issues, and other network degradation affecting OT systems.
• Perform advanced packet and protocol analysis using tools such as Wireshark to identify and resolve network issues affecting physical machinery and facility control systems.
• Coordinate troubleshooting and remediation activities with facility engineers, mechanical engineers, SCADA/BMS vendors, cybersecurity personnel, and other technical stakeholders.
• Evaluate network capacity, performance, latency, jitter, bandwidth utilization, and equipment lifecycle requirements.
• Develop and maintain network topology diagrams, hardware/software inventories, system baselines, configuration documentation, and Standard Operating Procedures.
• Maintain comprehensive backups of industrial switches, routers, firewalls, and other critical network device configurations.
• Support DoD Risk Management Framework activities for Platform IT and FRCS environments, including development and maintenance of technical artifacts, PPSM documentation, topology diagrams, vulnerability scan information, system inventories, and POA&M support.
• Participate in Military Construction (MILCON), Sustainment, Restoration and Modernization (SRM), and facility modernization design reviews at applicable design phases.
• Review proposed network architectures, Bills of Materials, firewall requirements, and PPSM submissions for compliance with NAVFAC, DoD cybersecurity, and OT architecture requirements.
• Provide subject matter expertise during system integration, testing, cybersecurity commissioning, and commissioning of new control systems and building automation systems.
• Support incident root-cause analysis and develop corrective actions designed to prevent recurrence of OT network outages or service degradation.
• Maintain all network activities in accordance with applicable DoD, Department of the Navy, NAVFAC, cybersecurity, CUI, and information safeguarding requirements.