Sr. OT Network Architect

Sr. OT Network Architect 3.7 3.7 out of 5 stars Manassas, VA 20109 $75

• $80 an hour
• Contract Johnson Service Group Inc. 186 reviews $75
• $80 an hour
• Contract Johnson Service Group is recruiting a Sr. OT Network Architect for a great client of ours in Manassas, VA . This is a 6-month plus contract with the opportunity to extend or convert to direct employee. Pay range is between $75/hr
• $80/hr . Must be on site 5 days a week.
• Must be a US citizen or Green Card Holder

•

JOB DESCRIPTION

Architecture & Design Design and implement a segmented OT network architecture transitioning from flat Layer 2 networks to SD-WAN-enabled, zone-based architectures. Define network segmentation strategy (ISA/IEC 62443 zones and conduits model) to isolate critical OT assets and control east-west traffic. Engineer ring and/or resilient topologies across substations and core OT sites to ensure deterministic communication and fault tolerance.

Develop SD-WAN design standards including:

Underlay/overlay architecture Path selection policies (latency, jitter, packet loss) QoS for ICS protocols (e.g., DNP3, Modbus, IEC 61850) Security & Compliance Develop and enforce OT-specific cybersecurity controls, including micro-segmentation, firewall zoning, and least-privilege access. Define and implement firewall policies to restrict inter-zone communication and prevent unauthorized access to OT systems. Conduct risk and vulnerability assessments aligned with OT threat models (ransomware, lateral movement, supply chain risks). Ensure compliance with

NERC CIP

standards and other applicable frameworks. Implementation & Operations Lead deployment of SD-WAN solutions across OT sites, including integration with existing switching infrastructure (e.g., industrial-grade switches). Configure and maintain high availability mechanisms: Redundant paths and failover (active/active or active/standby) Rapid spanning tree / ERPS / MPLS-TP where applicable Support incident response and root cause analysis for OT network disruptions. Manage projects and deliver on time with periodic status reports to management.

BASIC QUALIFICATIONS

10+ years of experience in network design and architecture, preferably in OT environments. Experience with industrial protocols (e.g., Modbus, DNP3, OPC, Ethernet/IP). Familiarity with IT/OT convergence principles.

DESIRED SKILLS

Strong understanding of networking concepts, including routing, switching, and firewall configurations. Proficiency in network monitoring and management tools. Knowledge of cybersecurity best practices for OT networks. Experience with industrial control systems (ICS) and SCADA systems.

MINIMUM TECHNICAL EXPERIENCE

Knowledge of design, configuration, installation, testing, and maintenance of local and wide area computer wired and wireless networks (Cisco Systems preferred). Knowledge of computer network characteristics, network operating system software, and network components Troubleshooting skills and the ability to diagnose/resolve network system problems. Ability to interpret and apply complex technical manuals and reference materials. Ability to assist with developing network security and related procedures; and performing network management activities.

EDUCATION REQUIREMENTS

Bachelor's degree in computer science, computer networks, or a related field. Certification in related fields (CCNA, CCNP) required. Security and Cisco Certified Internetwork Expert (CCIE), and experience in Extreme network switches is a plus JSG offers medical, dental, vision, life insurance options, short-term disability, 401(k), weekly pay, and more. Johnson Service Group (JSG) is an Equal Opportunity Employer. JSG provides equal employment opportunities to all applicants and employees without regard to race, color, religion, sex, age, sexual orientation, gender identity, national origin, disability, marital status, protected veteran status, or any other characteristic protected by law. #D600