The Three Core Cybersecurity Functions in Industrial Control Systems (ICS)

Industrial Control Systems (ICS) are crucial to critical infrastructure across industries like energy, manufacturing, and transportation. As cyber threats evolve, securing these systems is more important than ever. This article focuses on the three core cybersecurity functions within ICS: the View Function, the Monitor Function, and the Control Function—and how they can be secured.

1. Securing the View Function

The View Function provides operators with real-time data on system status through dashboards and interfaces.

Cybersecurity Implications:

- Data Manipulation: Attackers could alter displayed data, leading to dangerous decisions.

- Data Exposure: Sensitive operational data could be intercepted and exploited.

- Disruption: Denial-of-Service (DoS) attacks could prevent access to critical information.

Cybersecurity Strategies:

- Data Validation: Implement automated checks to ensure data integrity.

- Access Controls: Use multi-factor authentication (MFA) and encryption to protect data.

- Redundancy: Design redundant systems to maintain availability even if attacked.

2. Securing the Monitor Function

The Monitor Function continuously tracks system status and detects anomalies.

Cybersecurity Implications:

- False Data Injection: Attackers could inject false data to hide issues.

- Tampering: Compromised alerts could leave attacks undetected.

- Delayed Response: Integrity attacks could delay incident detection and response.

Cybersecurity Strategies:

- Data Integrity: Use encryption and hashing to verify data accuracy.

- Anomaly Detection: Implement machine learning-based systems to detect unusual patterns.

- Real-Time Monitoring: Set up continuous monitoring with real-time alerts.

3. Securing the Control Function

The Control Function executes commands that directly manipulate industrial processes.

Cybersecurity Implications:

- Malicious Commands: Attackers could issue harmful commands, disrupting operations.

- Unauthorized Access: Gaining control over this function could lead to severe damage.

- System Resilience: A breach here could cause uncontrolled shutdowns or harm.

Cybersecurity Strategies:

- Secure Protocols: Upgrade to secure communication protocols that protect command integrity.

- Access Controls: Implement strong access controls and multi-factor authentication.

- Resilient Design: Build systems with fail-safes that ensure safe shutdowns in case of attacks.

Balancing Availability and Security

In ICS, availability has traditionally been prioritized, often at the expense of security. Many ICS protocols, like Modbus and DNP3, were not designed with security in mind, making them vulnerable. As ICS integrates more with IT networks, the need for security alongside availability is critical.

Achieving Balance

To protect ICS, cybersecurity engineers must:

- View Function: Use data validation, access controls, and redundancy.

- Monitor Function: Implement data integrity checks, anomaly detection, and real-time monitoring.

- Control Function: Focus on secure protocols, access controls, and resilient system design.

By addressing these functions, ICS environments can remain secure and resilient against evolving cyber threats.