Operational Technology (OT) infrastructure is a collection of hardware and software systems used to control, process, and monitor physical devices and industrial processes. These systems are critical to the operation of industrial environments such as manufacturing plants, energy grids, transportation systems, and other critical infrastructure.

Understanding OT Networks and Protocols

OT networks are different from traditional IT networks in many ways:

Real-Time Operations: OT infrastructure relies on real-time data processing and communications to monitor and control physical processes. Continuous plant operations depend on the timely exchange of information between devices and systems.

Legacy Systems: Availability is the highest priority in OT environments. Many OT systems contain legacy devices running outdated operating systems and software that were not designed to defend against modern cyber threats. Protecting these systems from malicious actors is essential, and implementing a Defense-in-Depth strategy is one of the most effective security approaches.

Specialized Protocols: OT networks use specialized industrial protocols such as Modbus, DNP3, and others to facilitate communication between sensors, SCADA systems, and process control systems (PCS). Traditional network security devices often lack visibility into these protocols and may be unable to detect protocol-specific threats. As a result, specialized OT security solutions are required.

High Uptime: While traditional IT environments prioritize protecting data confidentiality, OT environments place the highest priority on ensuring continuous system availability. OT networks require low-latency communication to ensure the safe and efficient operation of industrial processes. Excessive latency can lead to operational disruptions, equipment damage, environmental incidents, or even risks to human safety.

Environmental: Continuous environmental monitoring is essential to maintaining normal operations in industrial environments. Network devices deployed in OT environments must withstand harsh conditions such as extreme temperatures, vibration, dust, and humidity. Therefore, robust and resilient equipment is required.

The Security Challenges in OT Networks

Securing OT networks presents unique challenges:

Outdated Legacy system: Many OT devices have been in operation for more than a decade. Updating or replacing them is often difficult due to availability requirements and vendor discontinuation of software support, resulting in limited or no security patches.

Improper Network Segmentation: OT environments are often inadequately segmented, allowing attackers who compromise one device to move laterally across the network. Proper segmentation between IT and OT networks, as well as between control systems and field devices, is essential to limit the spread of attacks.

Weak Authentication and Access Control: Poor implementation of authentication and access control mechanisms can provide attackers with easy access to critical systems. Strong authentication methods, proper authorization policies, and role-based access controls should be implemented to secure OT environments.

Human Error: Configuration mistakes, poor security practices, and successful social engineering attacks can expose critical OT systems to threats. Regular employee training and cybersecurity awareness programs are essential to reduce these risks.

Limited Visibility: Visibility into network assets and communications is crucial for both IT and OT environments. Without adequate visibility, organizations cannot effectively detect, investigate, or respond to emerging threats.

Insecure operational protocols: Many OT protocols were developed decades ago when cybersecurity was not a primary consideration. As a result, these protocols often lack built-in security features such as authentication and encryption. Compensating security controls must therefore be implemented to mitigate associated risks.

How FortiGate Protects OT Networks

FortiGate provides a multi-layered security approach to protect OT networks and protocols:

Asset identification and Management: Organizations can identify asset locations, protocol usage, inventory information, network topology, and security posture through a combination of Fortinet solutions such as FortiGate NGFW, FortiNAC, and FortiSIEM.

Access Control: FortiGate enables secure access through multi-factor authentication (MFA), single sign-on (SSO), network access control (NAC), secure VPN connectivity, conditional access policies, and role-based access control (RBAC). These capabilities enhance security while simplifying user management. Proper access control ensures that only authorized personnel can access OT environments. A combination of FortiAuthenticator, FortiNAC, and FortiClient can be used to implement a secure access framework.

Network Segmentation: Network segmentation helps control traffic between corporate IT networks and industrial control systems. It enables micro-segmentation within VLANs, protects management and field devices, and secures communications between critical assets. A combination of FortiGate and FortiSwitch can be used to implement effective segmentation strategies.

Network Visibility and Monitoring: Comprehensive visibility can be achieved through integration with centralized monitoring platforms such as FortiSIEM and FortiAnalyzer. These solutions provide detailed insights into network traffic, device communications, industrial protocols, and asset inventories while enabling continuous monitoring of alerts, events, and security incidents.

Risk assessment and management: Risk management is a proactive process that helps organizations identify threats, assess vulnerabilities, and implement appropriate security controls. Key activities include threat hunting, audit reporting, incident response planning, secure backup strategies, and disaster recovery preparation. FortiSIEM, FortiManager, and FortiAnalyzer can support these risk management initiatives.

Core NGFW Security Features for OT Protection

Deep Packet Inspection (DPI): FortiGate performs Deep Packet Inspection (DPI) to analyze and filter traffic based on OT-specific protocols. This capability ensures that only legitimate traffic is permitted while preventing unauthorized access and protocol-based attacks.

Intrusion Prevention System (IPS): FortiGate’s Intrusion Prevention System (IPS) detects and blocks malicious activities targeting OT environments. It uses both signature-based detection to identify known threats and behavioral analysis to detect anomalous activities that may indicate emerging attacks.

Conclusion

As OT networks become increasingly integrated with IT systems, cybersecurity becomes more critical than ever. Fortinet’s comprehensive security portfolio addresses the unique challenges associated with securing OT networks and industrial protocols. By leveraging advanced NGFW capabilities such as Deep Packet Inspection, Intrusion Prevention, and network segmentation, Fortinet helps ensure that OT environments remain secure, resilient, and operational.

Implementing a comprehensive suite of Fortinet solutions not only protects OT networks from cyber threats but also supports the continuous and safe operation of critical industrial processes. As cyber threats continue to evolve in sophistication, organizations require reliable protection against both current and emerging risks. Fortinet provides the security technologies and expertise necessary to help organizations safeguard their industrial environments.