Job Summary
We are seeking an experienced Network Engineer to design, implement, maintain, and secure network infrastructure supporting an Operational Technology (OT) / industrial environment.
The role will primarily focus on managing a segmented and air-gapped network environment, ensuring reliable and secure communication between industrial systems, servers, network devices, and supporting infrastructure. The successful candidate will also be responsible for firewall management, site-to-site VPN connectivity, DMZ services, Microsoft Entra ID (Azure AD), and network security.
This role requires a strong understanding of both network infrastructure and cybersecurity principles, with particular emphasis on maintaining the availability, integrity, and security of OT environments.
Key Responsibilities
Network Infrastructure & OT Environment
- Configure, maintain, and troubleshoot network infrastructure within an air-gapped OT environment.
- Manage network switches, routers, firewalls, VLANs, routing, and network segmentation.
- Implement and maintain secure network segmentation between OT, IT, DMZ, and other network zones.
- Maintain accurate network diagrams, IP addressing schemes, configuration documentation, and network inventories.
- Perform network configuration changes while minimizing disruption to critical operational systems.
- Configure and troubleshoot site-to-site VPN connections between approved locations or network environments.
- Manage and maintain a DMZ environment hosting web-based services used by clients to upload files.
- Support network and authentication requirements associated with Microsoft Entra ID (formerly Azure Active Directory).
- Assist with identity-related network access, authentication, and connectivity issues.
Industrial Devices & OT Support
- Provide network support for industrial equipment, including industrial printers and other OT-connected devices.
- Troubleshoot communication issues between industrial devices, servers, and network infrastructure.
- Work with OT engineers, vendors, and equipment manufacturers to resolve network-related issues.
- Ensure industrial devices are appropriately segmented and protected from unauthorized network access.
- Understand the operational constraints of industrial environments, including the importance of availability and controlled change management.
- Setting up / troubleshoot SFTP connection.
Network Security & Compliance
- Apply cybersecurity best practices to OT and network infrastructure.
- Maintain strict access controls within the air-gapped environment.
- Identify and mitigate network security risks and vulnerabilities.
- Participate in security assessments, audits, and incident investigations where required; such as ISO 27001
- Maintain network security documentation and configuration baselines.
- Follow formal change management, backup, and disaster recovery procedures.
- Ensure changes to OT networks are properly assessed, tested, documented, and approved before implementation.
Requirements
Technical Skills
- 3+ years of experience in network engineering, preferably within industrial, manufacturing, critical infrastructure, or OT environments.
- Strong understanding of TCP/IP, VLANs, subnetting, routing, DNS, DHCP, and network troubleshooting.
- Hands-on experience with enterprise firewalls.
- Experience configuring and troubleshooting site-to-site VPNs.
- Experience with network segmentation and DMZ architecture.
- Working knowledge of Microsoft Entra ID / Azure AD.
- Experience supporting Windows-based servers and network-connected devices.
- Familiarity with network monitoring and diagnostic tools.
- Understanding of cybersecurity principles and secure network design.
OT / Industrial Experience
Experience working in an Operational Technology (OT), industrial, manufacturing, or air-gapped environment will be highly advantageous.
Candidates should understand the differences between traditional IT and OT environments, particularly:
- Availability and operational continuity are critical.
- Network changes must be carefully controlled and tested.
- Legacy systems and industrial equipment may have strict compatibility requirements.
- Security controls must be implemented without disrupting industrial operations.
- Network segmentation and controlled access are essential to protecting OT systems.
Key Competencies
- Strong analytical and troubleshooting skills.
- Good understanding of network security.
- Ability to work independently in a controlled and security-sensitive environment.
- Strong documentation and communication skills.
- Ability to work with OT engineers, vendors, and external clients.
- Strong attention to detail.
- Good understanding of change management and risk assessment.
- Ability to respond effectively to network incidents and service disruptions.
- Willingness to work outside normal business hours for planned maintenance or critical incidents when required.